Re: [PATCH v5 3/4] soc: aspeed: Add eSPI driver

From: Christophe JAILLET
Date: Wed May 18 2022 - 15:13:21 EST

Hi,

inline a few comments about resources not freed in error handling paths in case it helps.

CJ

Le 16/05/2022 à 02:54, Chia-Wei Wang a écrit :
The Aspeed eSPI controller is slave device to communicate with
the master through the Enhanced Serial Peripheral Interface (eSPI).
All of the four eSPI channels, namely peripheral, virtual wire,
out-of-band, and flash are supported.

Signed-off-by: Chia-Wei Wang <chiawei_wang-SAlXDmAnmOAqDJ6do+/SaQ@xxxxxxxxxxxxxxxx>
Reported-by: kernel test robot <lkp-ral2JQCrhuEAvxtiuMwx3w@xxxxxxxxxxxxxxxx>
---
drivers/soc/aspeed/Kconfig | 11 +
drivers/soc/aspeed/Makefile | 5 +
drivers/soc/aspeed/aspeed-espi-ctrl.c | 214 ++++++++++
drivers/soc/aspeed/aspeed-espi-ctrl.h | 309 ++++++++++++++
drivers/soc/aspeed/aspeed-espi-flash.c | 352 ++++++++++++++++
drivers/soc/aspeed/aspeed-espi-flash.h | 45 ++
drivers/soc/aspeed/aspeed-espi-ioc.h | 195 +++++++++
drivers/soc/aspeed/aspeed-espi-oob.c | 558 +++++++++++++++++++++++++
drivers/soc/aspeed/aspeed-espi-oob.h | 70 ++++
drivers/soc/aspeed/aspeed-espi-perif.c | 511 ++++++++++++++++++++++
drivers/soc/aspeed/aspeed-espi-perif.h | 45 ++
drivers/soc/aspeed/aspeed-espi-vw.c | 142 +++++++
drivers/soc/aspeed/aspeed-espi-vw.h | 21 +
13 files changed, 2478 insertions(+)
create mode 100644 drivers/soc/aspeed/aspeed-espi-ctrl.c
create mode 100644 drivers/soc/aspeed/aspeed-espi-ctrl.h
create mode 100644 drivers/soc/aspeed/aspeed-espi-flash.c
create mode 100644 drivers/soc/aspeed/aspeed-espi-flash.h
create mode 100644 drivers/soc/aspeed/aspeed-espi-ioc.h
create mode 100644 drivers/soc/aspeed/aspeed-espi-oob.c
create mode 100644 drivers/soc/aspeed/aspeed-espi-oob.h
create mode 100644 drivers/soc/aspeed/aspeed-espi-perif.c
create mode 100644 drivers/soc/aspeed/aspeed-espi-perif.h
create mode 100644 drivers/soc/aspeed/aspeed-espi-vw.c
create mode 100644 drivers/soc/aspeed/aspeed-espi-vw.h

diff --git a/drivers/soc/aspeed/Kconfig b/drivers/soc/aspeed/Kconfig
index f579ee0b5afa..b56414dc0743 100644
--- a/drivers/soc/aspeed/Kconfig
+++ b/drivers/soc/aspeed/Kconfig
@@ -52,6 +52,17 @@ config ASPEED_SOCINFO
help
Say yes to support decoding of ASPEED BMC information.
+config ASPEED_ESPI
+ bool "ASPEED eSPI slave driver"
+ select REGMAP
+ select MFD_SYSCON
+ default n
+ help
+ Enable driver support for the Aspeed eSPI engine. The eSPI engine
+ plays as a slave device in BMC to communicate with the Host over
+ the eSPI interface. The four eSPI channels, namely peripheral,
+ virtual wire, out-of-band, and flash are supported.
+
endmenu
endif
diff --git a/drivers/soc/aspeed/Makefile b/drivers/soc/aspeed/Makefile
index b35d74592964..1bc433be7e93 100644
--- a/drivers/soc/aspeed/Makefile
+++ b/drivers/soc/aspeed/Makefile
@@ -4,3 +4,8 @@ obj-$(CONFIG_ASPEED_LPC_SNOOP) += aspeed-lpc-snoop.o
obj-$(CONFIG_ASPEED_UART_ROUTING) += aspeed-uart-routing.o
obj-$(CONFIG_ASPEED_P2A_CTRL) += aspeed-p2a-ctrl.o
obj-$(CONFIG_ASPEED_SOCINFO) += aspeed-socinfo.o
+obj-$(CONFIG_ASPEED_ESPI) += aspeed-espi-ctrl.o \
+ aspeed-espi-perif.o \
+ aspeed-espi-vw.o \
+ aspeed-espi-oob.o \
+ aspeed-espi-flash.o
diff --git a/drivers/soc/aspeed/aspeed-espi-ctrl.c b/drivers/soc/aspeed/aspeed-espi-ctrl.c
new file mode 100644
index 000000000000..ce2967f851f2
--- /dev/null
+++ b/drivers/soc/aspeed/aspeed-espi-ctrl.c
@@ -0,0 +1,214 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright 2021 Aspeed Technology Inc.
+ */
+#include <linux/io.h>
+#include <linux/irq.h>
+#include <linux/clk.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/miscdevice.h>
+#include <linux/dma-mapping.h>
+#include <linux/mfd/syscon.h>
+#include <linux/regmap.h>
+#include <linux/uaccess.h>
+#include <linux/vmalloc.h>
+
+#include "aspeed-espi-ioc.h"
+#include "aspeed-espi-ctrl.h"
+#include "aspeed-espi-perif.h"
+#include "aspeed-espi-vw.h"
+#include "aspeed-espi-oob.h"
+#include "aspeed-espi-flash.h"
+
+#define DEVICE_NAME "aspeed-espi-ctrl"
+
+static irqreturn_t aspeed_espi_ctrl_isr(int irq, void *arg)
+{
+ uint32_t sts;
+ struct aspeed_espi_ctrl *espi_ctrl = (struct aspeed_espi_ctrl *)arg;
+
+ regmap_read(espi_ctrl->map, ESPI_INT_STS, &sts);
+
+ if (sts & ESPI_INT_STS_PERIF_BITS) {
+ aspeed_espi_perif_event(sts, espi_ctrl->perif);
+ regmap_write(espi_ctrl->map, ESPI_INT_STS, sts & ESPI_INT_STS_PERIF_BITS);
+ }
+
+ if (sts & ESPI_INT_STS_VW_BITS) {
+ aspeed_espi_vw_event(sts, espi_ctrl->vw);
+ regmap_write(espi_ctrl->map, ESPI_INT_STS, sts & ESPI_INT_STS_VW_BITS);
+ }
+
+ if (sts & (ESPI_INT_STS_OOB_BITS)) {
+ aspeed_espi_oob_event(sts, espi_ctrl->oob);
+ regmap_write(espi_ctrl->map, ESPI_INT_STS, sts & ESPI_INT_STS_OOB_BITS);
+ }
+
+ if (sts & ESPI_INT_STS_FLASH_BITS) {
+ aspeed_espi_flash_event(sts, espi_ctrl->flash);
+ regmap_write(espi_ctrl->map, ESPI_INT_STS, sts & ESPI_INT_STS_FLASH_BITS);
+ }
+
+ if (sts & ESPI_INT_STS_HW_RST_DEASSERT) {
+ aspeed_espi_perif_enable(espi_ctrl->perif);
+ aspeed_espi_vw_enable(espi_ctrl->vw);
+ aspeed_espi_oob_enable(espi_ctrl->oob);
+ aspeed_espi_flash_enable(espi_ctrl->flash);
+
+ regmap_write(espi_ctrl->map, ESPI_SYSEVT_INT_T0, 0x0);
+ regmap_write(espi_ctrl->map, ESPI_SYSEVT_INT_T1, 0x0);
+ regmap_write(espi_ctrl->map, ESPI_SYSEVT_INT_EN, 0xffffffff);
+
+ regmap_write(espi_ctrl->map, ESPI_SYSEVT1_INT_T0, 0x1);
+ regmap_write(espi_ctrl->map, ESPI_SYSEVT1_INT_EN, 0x1);
+
+ if (espi_ctrl->model->version == ESPI_AST2500)
+ regmap_write(espi_ctrl->map, ESPI_SYSEVT_INT_T2,
+ ESPI_SYSEVT_INT_T2_HOST_RST_WARN |
+ ESPI_SYSEVT_INT_T2_OOB_RST_WARN);
+
+ regmap_update_bits(espi_ctrl->map, ESPI_INT_EN,
+ ESPI_INT_EN_HW_RST_DEASSERT,
+ ESPI_INT_EN_HW_RST_DEASSERT);
+
+ regmap_update_bits(espi_ctrl->map, ESPI_SYSEVT,
+ ESPI_SYSEVT_SLV_BOOT_STS | ESPI_SYSEVT_SLV_BOOT_DONE,
+ ESPI_SYSEVT_SLV_BOOT_STS | ESPI_SYSEVT_SLV_BOOT_DONE);
+
+ regmap_write(espi_ctrl->map, ESPI_INT_STS, ESPI_INT_STS_HW_RST_DEASSERT);
+ }
+
+ return IRQ_HANDLED;
+}
+
+static int aspeed_espi_ctrl_probe(struct platform_device *pdev)
+{
+ int rc = 0;
+ struct aspeed_espi_ctrl *espi_ctrl;
+ struct device *dev = &pdev->dev;
+
+ espi_ctrl = devm_kzalloc(dev, sizeof(*espi_ctrl), GFP_KERNEL);
+ if (!espi_ctrl)
+ return -ENOMEM;
+
+ espi_ctrl->model = of_device_get_match_data(dev);
+
+ espi_ctrl->map = syscon_node_to_regmap(dev->parent->of_node);
+ if (IS_ERR(espi_ctrl->map)) {
+ dev_err(dev, "cannot get remap\n");
+ return -ENODEV;
+ }
+
+ espi_ctrl->irq = platform_get_irq(pdev, 0);
+ if (espi_ctrl->irq < 0)
+ return espi_ctrl->irq;
+
+ espi_ctrl->clk = devm_clk_get(dev, NULL);
+ if (IS_ERR(espi_ctrl->clk)) {
+ dev_err(dev, "cannot get clock\n");
+ return -ENODEV;
+ }
+
+ rc = clk_prepare_enable(espi_ctrl->clk);
+ if (rc) {
+ dev_err(dev, "cannot enable clock\n");
+ return rc;
+ }

This is never reverted, neither in an error handling path, nor in a .remove function. devm_add_action_or_reset()?

+
+ espi_ctrl->perif = aspeed_espi_perif_alloc(dev, espi_ctrl);
+ if (IS_ERR(espi_ctrl->perif)) {
+ dev_err(dev, "failed to allocate peripheral channel\n");
+ return PTR_ERR(espi_ctrl->perif);
+ }
+
+ espi_ctrl->vw = aspeed_espi_vw_alloc(dev, espi_ctrl);
+ if (IS_ERR(espi_ctrl->vw)) {
+ dev_err(dev, "failed to allocate virtual wire channel\n");
+ return PTR_ERR(espi_ctrl->vw);
+ }
+
+ espi_ctrl->oob = aspeed_espi_oob_alloc(dev, espi_ctrl);
+ if (IS_ERR(espi_ctrl->oob)) {
+ dev_err(dev, "failed to allocate out-of-band channel\n");
+ return PTR_ERR(espi_ctrl->oob);
+ }
+
+ espi_ctrl->flash = aspeed_espi_flash_alloc(dev, espi_ctrl);
+ if (rc) {
+ dev_err(dev, "failed to allocate flash channel\n");
+ return PTR_ERR(espi_ctrl->flash);
+ }
+
+ regmap_write(espi_ctrl->map, ESPI_SYSEVT_INT_T0, 0x0);
+ regmap_write(espi_ctrl->map, ESPI_SYSEVT_INT_T1, 0x0);
+ regmap_write(espi_ctrl->map, ESPI_SYSEVT_INT_EN, 0xffffffff);
+
+ regmap_write(espi_ctrl->map, ESPI_SYSEVT1_INT_T0, 0x1);
+ regmap_write(espi_ctrl->map, ESPI_SYSEVT1_INT_EN, 0x1);
+
+ rc = devm_request_irq(dev, espi_ctrl->irq,
+ aspeed_espi_ctrl_isr,
+ 0, DEVICE_NAME, espi_ctrl);
+ if (rc) {
+ dev_err(dev, "failed to request IRQ\n");
+ return rc;
+ }
+
+ regmap_update_bits(espi_ctrl->map, ESPI_INT_EN,
+ ESPI_INT_EN_HW_RST_DEASSERT,
+ ESPI_INT_EN_HW_RST_DEASSERT);
+
+ dev_set_drvdata(dev, espi_ctrl);
+
+ dev_info(dev, "module loaded\n");
+
+ return 0;
+}
+
+static int aspeed_espi_ctrl_remove(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct aspeed_espi_ctrl *espi_ctrl = dev_get_drvdata(dev);
+
+ aspeed_espi_perif_free(dev, espi_ctrl->perif);
+ aspeed_espi_vw_free(dev, espi_ctrl->vw);
+ aspeed_espi_oob_free(dev, espi_ctrl->oob);
+ aspeed_espi_flash_free(dev, espi_ctrl->flash);
+
+ return 0;
+}
+
+static const struct aspeed_espi_model ast2500_model = {
+ .version = ESPI_AST2500,
+};
+
+static const struct aspeed_espi_model ast2600_model = {
+ .version = ESPI_AST2600,
+};
+
+static const struct of_device_id aspeed_espi_ctrl_of_matches[] = {
+ { .compatible = "aspeed,ast2500-espi-ctrl",
+ .data = &ast2500_model },
+ { .compatible = "aspeed,ast2600-espi-ctrl",
+ .data = &ast2600_model },
+ { },
+};
+
+static struct platform_driver aspeed_espi_ctrl_driver = {
+ .driver = {
+ .name = DEVICE_NAME,
+ .of_match_table = aspeed_espi_ctrl_of_matches,
+ },
+ .probe = aspeed_espi_ctrl_probe,
+ .remove = aspeed_espi_ctrl_remove,
+};
+
+module_platform_driver(aspeed_espi_ctrl_driver);
+
+MODULE_AUTHOR("Chia-Wei Wang <chiawei_wang-SAlXDmAnmOAqDJ6do+/SaQ@xxxxxxxxxxxxxxxx>");
+MODULE_AUTHOR("Ryan Chen <ryan_chen-SAlXDmAnmOAqDJ6do+/SaQ@xxxxxxxxxxxxxxxx>");
+MODULE_DESCRIPTION("Control of Aspeed eSPI Slave Device");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/soc/aspeed/aspeed-espi-ctrl.h b/drivers/soc/aspeed/aspeed-espi-ctrl.h
new file mode 100644
index 000000000000..8e26cd647a7f
--- /dev/null
+++ b/drivers/soc/aspeed/aspeed-espi-ctrl.h
@@ -0,0 +1,309 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Copyright 2021 Aspeed Technology Inc.
+ */
+#ifndef _ASPEED_ESPI_CTRL_H_
+#define _ASPEED_ESPI_CTRL_H_
+
+#include <linux/bits.h>
+
+enum aspeed_espi_version {
+ ESPI_AST2500,
+ ESPI_AST2600,
+};
+
+struct aspeed_espi_model {
+ uint32_t version;
+};
+
+struct aspeed_espi_ctrl {
+ struct device *dev;
+
+ struct regmap *map;
+ struct clk *clk;
+
+ int irq;
+
+ struct aspeed_espi_perif *perif;
+ struct aspeed_espi_vw *vw;
+ struct aspeed_espi_oob *oob;
+ struct aspeed_espi_flash *flash;
+
+ const struct aspeed_espi_model *model;
+};
+
+/* eSPI register offset */
+#define ESPI_CTRL 0x000
+#define ESPI_CTRL_OOB_RX_SW_RST BIT(28)
+#define ESPI_CTRL_FLASH_TX_DMA_EN BIT(23)
+#define ESPI_CTRL_FLASH_RX_DMA_EN BIT(22)
+#define ESPI_CTRL_OOB_TX_DMA_EN BIT(21)
+#define ESPI_CTRL_OOB_RX_DMA_EN BIT(20)
+#define ESPI_CTRL_PERIF_NP_TX_DMA_EN BIT(19)
+#define ESPI_CTRL_PERIF_PC_TX_DMA_EN BIT(17)
+#define ESPI_CTRL_PERIF_PC_RX_DMA_EN BIT(16)
+#define ESPI_CTRL_FLASH_SW_MODE_MASK GENMASK(11, 10)
+#define ESPI_CTRL_FLASH_SW_MODE_SHIFT 10
+#define ESPI_CTRL_PERIF_PC_RX_DMA_EN BIT(16)
+#define ESPI_CTRL_VW_GPIO_SW_MODE BIT(9)
+#define ESPI_CTRL_FLASH_SW_RDY BIT(7)
+#define ESPI_CTRL_OOB_SW_RDY BIT(4)
+#define ESPI_CTRL_VW_SW_RDY BIT(3)
+#define ESPI_CTRL_PERIF_SW_RDY BIT(1)
+#define ESPI_STS 0x004
+#define ESPI_INT_STS 0x008
+#define ESPI_INT_STS_HW_RST_DEASSERT BIT(31)
+#define ESPI_INT_STS_OOB_RX_TMOUT BIT(23)
+#define ESPI_INT_STS_VW_SYSEVT1 BIT(22)
+#define ESPI_INT_STS_FLASH_TX_ERR BIT(21)
+#define ESPI_INT_STS_OOB_TX_ERR BIT(20)
+#define ESPI_INT_STS_FLASH_TX_ABT BIT(19)
+#define ESPI_INT_STS_OOB_TX_ABT BIT(18)
+#define ESPI_INT_STS_PERIF_NP_TX_ABT BIT(17)
+#define ESPI_INT_STS_PERIF_PC_TX_ABT BIT(16)
+#define ESPI_INT_STS_FLASH_RX_ABT BIT(15)
+#define ESPI_INT_STS_OOB_RX_ABT BIT(14)
+#define ESPI_INT_STS_PERIF_NP_RX_ABT BIT(13)
+#define ESPI_INT_STS_PERIF_PC_RX_ABT BIT(12)
+#define ESPI_INT_STS_PERIF_NP_TX_ERR BIT(11)
+#define ESPI_INT_STS_PERIF_PC_TX_ERR BIT(10)
+#define ESPI_INT_STS_VW_GPIOEVT BIT(9)
+#define ESPI_INT_STS_VW_SYSEVT BIT(8)
+#define ESPI_INT_STS_FLASH_TX_CMPLT BIT(7)
+#define ESPI_INT_STS_FLASH_RX_CMPLT BIT(6)
+#define ESPI_INT_STS_OOB_TX_CMPLT BIT(5)
+#define ESPI_INT_STS_OOB_RX_CMPLT BIT(4)
+#define ESPI_INT_STS_PERIF_NP_TX_CMPLT BIT(3)
+#define ESPI_INT_STS_PERIF_PC_TX_CMPLT BIT(1)
+#define ESPI_INT_STS_PERIF_PC_RX_CMPLT BIT(0)
+#define ESPI_INT_EN 0x00c
+#define ESPI_INT_EN_HW_RST_DEASSERT BIT(31)
+#define ESPI_INT_EN_OOB_RX_TMOUT BIT(23)
+#define ESPI_INT_EN_VW_SYSEVT1 BIT(22)
+#define ESPI_INT_EN_FLASH_TX_ERR BIT(21)
+#define ESPI_INT_EN_OOB_TX_ERR BIT(20)
+#define ESPI_INT_EN_FLASH_TX_ABT BIT(19)
+#define ESPI_INT_EN_OOB_TX_ABT BIT(18)
+#define ESPI_INT_EN_PERIF_NP_TX_ABT BIT(17)
+#define ESPI_INT_EN_PERIF_PC_TX_ABT BIT(16)
+#define ESPI_INT_EN_FLASH_RX_ABT BIT(15)
+#define ESPI_INT_EN_OOB_RX_ABT BIT(14)
+#define ESPI_INT_EN_PERIF_NP_RX_ABT BIT(13)
+#define ESPI_INT_EN_PERIF_PC_RX_ABT BIT(12)
+#define ESPI_INT_EN_PERIF_NP_TX_ERR BIT(11)
+#define ESPI_INT_EN_PERIF_PC_TX_ERR BIT(10)
+#define ESPI_INT_EN_VW_GPIOEVT BIT(9)
+#define ESPI_INT_EN_VW_SYSEVT BIT(8)
+#define ESPI_INT_EN_FLASH_TX_CMPLT BIT(7)
+#define ESPI_INT_EN_FLASH_RX_CMPLT BIT(6)
+#define ESPI_INT_EN_OOB_TX_CMPLT BIT(5)
+#define ESPI_INT_EN_OOB_RX_CMPLT BIT(4)
+#define ESPI_INT_EN_PERIF_NP_TX_CMPLT BIT(3)
+#define ESPI_INT_EN_PERIF_PC_TX_CMPLT BIT(1)
+#define ESPI_INT_EN_PERIF_PC_RX_CMPLT BIT(0)
+#define ESPI_PERIF_PC_RX_DMA 0x010
+#define ESPI_PERIF_PC_RX_CTRL 0x014
+#define ESPI_PERIF_PC_RX_CTRL_PEND_SERV BIT(31)
+#define ESPI_PERIF_PC_RX_CTRL_LEN_MASK GENMASK(23, 12)
+#define ESPI_PERIF_PC_RX_CTRL_LEN_SHIFT 12
+#define ESPI_PERIF_PC_RX_CTRL_TAG_MASK GENMASK(11, 8)
+#define ESPI_PERIF_PC_RX_CTRL_TAG_SHIFT 8
+#define ESPI_PERIF_PC_RX_CTRL_CYC_MASK GENMASK(7, 0)
+#define ESPI_PERIF_PC_RX_CTRL_CYC_SHIFT 0
+#define ESPI_PERIF_PC_RX_PORT 0x018
+#define ESPI_PERIF_PC_TX_DMA 0x020
+#define ESPI_PERIF_PC_TX_CTRL 0x024
+#define ESPI_PERIF_PC_TX_CTRL_TRIGGER BIT(31)
+#define ESPI_PERIF_PC_TX_CTRL_LEN_MASK GENMASK(23, 12)
+#define ESPI_PERIF_PC_TX_CTRL_LEN_SHIFT 12
+#define ESPI_PERIF_PC_TX_CTRL_TAG_MASK GENMASK(11, 8)
+#define ESPI_PERIF_PC_TX_CTRL_TAG_SHIFT 8
+#define ESPI_PERIF_PC_TX_CTRL_CYC_MASK GENMASK(7, 0)
+#define ESPI_PERIF_PC_TX_CTRL_CYC_SHIFT 0
+#define ESPI_PERIF_PC_TX_PORT 0x028
+#define ESPI_PERIF_NP_TX_DMA 0x030
+#define ESPI_PERIF_NP_TX_CTRL 0x034
+#define ESPI_PERIF_NP_TX_CTRL_TRIGGER BIT(31)
+#define ESPI_PERIF_NP_TX_CTRL_LEN_MASK GENMASK(23, 12)
+#define ESPI_PERIF_NP_TX_CTRL_LEN_SHIFT 12
+#define ESPI_PERIF_NP_TX_CTRL_TAG_MASK GENMASK(11, 8)
+#define ESPI_PERIF_NP_TX_CTRL_TAG_SHIFT 8
+#define ESPI_PERIF_NP_TX_CTRL_CYC_MASK GENMASK(7, 0)
+#define ESPI_PERIF_NP_TX_CTRL_CYC_SHIFT 0
+#define ESPI_PERIF_NP_TX_PORT 0x038
+#define ESPI_OOB_RX_DMA 0x040
+#define ESPI_OOB_RX_CTRL 0x044
+#define ESPI_OOB_RX_CTRL_PEND_SERV BIT(31)
+#define ESPI_OOB_RX_CTRL_LEN_MASK GENMASK(23, 12)
+#define ESPI_OOB_RX_CTRL_LEN_SHIFT 12
+#define ESPI_OOB_RX_CTRL_TAG_MASK GENMASK(11, 8)
+#define ESPI_OOB_RX_CTRL_TAG_SHIFT 8
+#define ESPI_OOB_RX_CTRL_CYC_MASK GENMASK(7, 0)
+#define ESPI_OOB_RX_CTRL_CYC_SHIFT 0
+#define ESPI_OOB_RX_PORT 0x048
+#define ESPI_OOB_TX_DMA 0x050
+#define ESPI_OOB_TX_CTRL 0x054
+#define ESPI_OOB_TX_CTRL_TRIGGER BIT(31)
+#define ESPI_OOB_TX_CTRL_LEN_MASK GENMASK(23, 12)
+#define ESPI_OOB_TX_CTRL_LEN_SHIFT 12
+#define ESPI_OOB_TX_CTRL_TAG_MASK GENMASK(11, 8)
+#define ESPI_OOB_TX_CTRL_TAG_SHIFT 8
+#define ESPI_OOB_TX_CTRL_CYC_MASK GENMASK(7, 0)
+#define ESPI_OOB_TX_CTRL_CYC_SHIFT 0
+#define ESPI_OOB_TX_PORT 0x058
+#define ESPI_FLASH_RX_DMA 0x060
+#define ESPI_FLASH_RX_CTRL 0x064
+#define ESPI_FLASH_RX_CTRL_PEND_SERV BIT(31)
+#define ESPI_FLASH_RX_CTRL_LEN_MASK GENMASK(23, 12)
+#define ESPI_FLASH_RX_CTRL_LEN_SHIFT 12
+#define ESPI_FLASH_RX_CTRL_TAG_MASK GENMASK(11, 8)
+#define ESPI_FLASH_RX_CTRL_TAG_SHIFT 8
+#define ESPI_FLASH_RX_CTRL_CYC_MASK GENMASK(7, 0)
+#define ESPI_FLASH_RX_CTRL_CYC_SHIFT 0
+#define ESPI_FLASH_RX_PORT 0x068
+#define ESPI_FLASH_TX_DMA 0x070
+#define ESPI_FLASH_TX_CTRL 0x074
+#define ESPI_FLASH_TX_CTRL_TRIGGER BIT(31)
+#define ESPI_FLASH_TX_CTRL_LEN_MASK GENMASK(23, 12)
+#define ESPI_FLASH_TX_CTRL_LEN_SHIFT 12
+#define ESPI_FLASH_TX_CTRL_TAG_MASK GENMASK(11, 8)
+#define ESPI_FLASH_TX_CTRL_TAG_SHIFT 8
+#define ESPI_FLASH_TX_CTRL_CYC_MASK GENMASK(7, 0)
+#define ESPI_FLASH_TX_CTRL_CYC_SHIFT 0
+#define ESPI_FLASH_TX_PORT 0x078
+#define ESPI_CTRL2 0x080
+#define ESPI_CTRL2_MEMCYC_RD_DIS BIT(6)
+#define ESPI_CTRL2_MEMCYC_WR_DIS BIT(4)
+#define ESPI_PERIF_PC_RX_SADDR 0x084
+#define ESPI_PERIF_PC_RX_TADDR 0x088
+#define ESPI_PERIF_PC_RX_MASK 0x08c
+#define ESPI_PERIF_PC_RX_MASK_CFG_WP BIT(0)
+#define ESPI_SYSEVT_INT_EN 0x094
+#define ESPI_SYSEVT 0x098
+#define ESPI_SYSEVT_HOST_RST_ACK BIT(27)
+#define ESPI_SYSEVT_RST_CPU_INIT BIT(26)
+#define ESPI_SYSEVT_SLV_BOOT_STS BIT(23)
+#define ESPI_SYSEVT_NON_FATAL_ERR BIT(22)
+#define ESPI_SYSEVT_FATAL_ERR BIT(21)
+#define ESPI_SYSEVT_SLV_BOOT_DONE BIT(20)
+#define ESPI_SYSEVT_OOB_RST_ACK BIT(16)
+#define ESPI_SYSEVT_NMI_OUT BIT(10)
+#define ESPI_SYSEVT_SMI_OUT BIT(9)
+#define ESPI_SYSEVT_HOST_RST_WARN BIT(8)
+#define ESPI_SYSEVT_OOB_RST_WARN BIT(6)
+#define ESPI_SYSEVT_PLTRSTN BIT(5)
+#define ESPI_SYSEVT_SUSPEND BIT(4)
+#define ESPI_SYSEVT_S5_SLEEP BIT(2)
+#define ESPI_SYSEVT_S4_SLEEP BIT(1)
+#define ESPI_SYSEVT_S3_SLEEP BIT(0)
+#define ESPI_VW_GPIO_VAL 0x09c
+#define ESPI_GEN_CAP_N_CONF 0x0a0
+#define ESPI_CH0_CAP_N_CONF 0x0a4
+#define ESPI_CH1_CAP_N_CONF 0x0a8
+#define ESPI_CH2_CAP_N_CONF 0x0ac
+#define ESPI_CH3_CAP_N_CONF 0x0b0
+#define ESPI_CH3_CAP_N_CONF2 0x0b4
+#define ESPI_SYSEVT1_INT_EN 0x100
+#define ESPI_SYSEVT1 0x104
+#define ESPI_SYSEVT1_SUSPEND_ACK BIT(20)
+#define ESPI_SYSEVT1_SUSPEND_WARN BIT(0)
+#define ESPI_SYSEVT_INT_T0 0x110
+#define ESPI_SYSEVT_INT_T1 0x114
+#define ESPI_SYSEVT_INT_T2 0x118
+#define ESPI_SYSEVT_INT_T2_HOST_RST_WARN ESPI_SYSEVT_HOST_RST_WARN
+#define ESPI_SYSEVT_INT_T2_OOB_RST_WARN ESPI_SYSEVT_OOB_RST_WARN
+#define ESPI_SYSEVT_INT_STS 0x11c
+#define ESPI_SYSEVT_INT_STS_NMI_OUT ESPI_SYSEVT_NMI_OUT
+#define ESPI_SYSEVT_INT_STS_SMI_OUT ESPI_SYSEVT_SMI_OUT
+#define ESPI_SYSEVT_INT_STS_HOST_RST_WARN ESPI_SYSEVT_HOST_RST_WARN
+#define ESPI_SYSEVT_INT_STS_OOB_RST_WARN ESPI_SYSEVT_OOB_RST_WARN
+#define ESPI_SYSEVT_INT_STS_PLTRSTN ESPI_SYSEVT_PLTRSTN
+#define ESPI_SYSEVT_INT_STS_SUSPEND ESPI_SYSEVT_SUSPEND
+#define ESPI_SYSEVT_INT_STS_S5_SLEEP ESPI_SYSEVT_INT_S5_SLEEP
+#define ESPI_SYSEVT_INT_STS_S4_SLEEP ESPI_SYSEVT_INT_S4_SLEEP
+#define ESPI_SYSEVT_INT_STS_S3_SLEEP ESPI_SYSEVT_INT_S3_SLEEP
+#define ESPI_SYSEVT1_INT_T0 0x120
+#define ESPI_SYSEVT1_INT_T1 0x124
+#define ESPI_SYSEVT1_INT_T2 0x128
+#define ESPI_SYSEVT1_INT_STS 0x12c
+#define ESPI_SYSEVT1_INT_STS_SUSPEND_WARN ESPI_SYSEVT1_SUSPEND_WARN
+#define ESPI_OOB_RX_DMA_RB_SIZE 0x130
+#define ESPI_OOB_RX_DMA_RD_PTR 0x134
+#define ESPI_OOB_RX_DMA_RD_PTR_UPDATE BIT(31)
+#define ESPI_OOB_RX_DMA_WS_PTR 0x138
+#define ESPI_OOB_RX_DMA_WS_PTR_RECV_EN BIT(31)
+#define ESPI_OOB_RX_DMA_WS_PTR_SP_MASK GENMASK(27, 16)
+#define ESPI_OOB_RX_DMA_WS_PTR_SP_SHIFT 16
+#define ESPI_OOB_RX_DMA_WS_PTR_WP_MASK GENMASK(11, 0)
+#define ESPI_OOB_RX_DMA_WS_PTR_WP_SHIFT 0
+#define ESPI_OOB_TX_DMA_RB_SIZE 0x140
+#define ESPI_OOB_TX_DMA_RD_PTR 0x144
+#define ESPI_OOB_TX_DMA_RD_PTR_UPDATE BIT(31)
+#define ESPI_OOB_TX_DMA_WR_PTR 0x148
+#define ESPI_OOB_TX_DMA_WR_PTR_SEND_EN BIT(31)
+
+/* collect ESPI_INT_STS bits of eSPI channels for convenience */
+#define ESPI_INT_STS_PERIF_BITS \
+ (ESPI_INT_STS_PERIF_NP_TX_ABT | \
+ ESPI_INT_STS_PERIF_PC_TX_ABT | \
+ ESPI_INT_STS_PERIF_NP_RX_ABT | \
+ ESPI_INT_STS_PERIF_PC_RX_ABT | \
+ ESPI_INT_STS_PERIF_NP_TX_ERR | \
+ ESPI_INT_STS_PERIF_PC_TX_ERR | \
+ ESPI_INT_STS_PERIF_NP_TX_CMPLT | \
+ ESPI_INT_STS_PERIF_PC_TX_CMPLT | \
+ ESPI_INT_STS_PERIF_PC_RX_CMPLT)
+
+#define ESPI_INT_STS_VW_BITS \
+ (ESPI_INT_STS_VW_SYSEVT1 | \
+ ESPI_INT_STS_VW_GPIOEVT | \
+ ESPI_INT_STS_VW_SYSEVT)
+
+#define ESPI_INT_STS_OOB_BITS \
+ (ESPI_INT_STS_OOB_RX_TMOUT | \
+ ESPI_INT_STS_OOB_TX_ERR | \
+ ESPI_INT_STS_OOB_TX_ABT | \
+ ESPI_INT_STS_OOB_RX_ABT | \
+ ESPI_INT_STS_OOB_TX_CMPLT | \
+ ESPI_INT_STS_OOB_RX_CMPLT)
+
+#define ESPI_INT_STS_FLASH_BITS \
+ (ESPI_INT_STS_FLASH_TX_ERR | \
+ ESPI_INT_STS_FLASH_TX_ABT | \
+ ESPI_INT_STS_FLASH_RX_ABT | \
+ ESPI_INT_STS_FLASH_TX_CMPLT | \
+ ESPI_INT_STS_FLASH_RX_CMPLT)
+
+/* collect ESPI_INT_EN bits of eSPI channels for convenience */
+#define ESPI_INT_EN_PERIF_BITS \
+ (ESPI_INT_EN_PERIF_NP_TX_ABT | \
+ ESPI_INT_EN_PERIF_PC_TX_ABT | \
+ ESPI_INT_EN_PERIF_NP_RX_ABT | \
+ ESPI_INT_EN_PERIF_PC_RX_ABT | \
+ ESPI_INT_EN_PERIF_NP_TX_ERR | \
+ ESPI_INT_EN_PERIF_PC_TX_ERR | \
+ ESPI_INT_EN_PERIF_NP_TX_CMPLT | \
+ ESPI_INT_EN_PERIF_PC_TX_CMPLT | \
+ ESPI_INT_EN_PERIF_PC_RX_CMPLT)
+
+#define ESPI_INT_EN_VW_BITS \
+ (ESPI_INT_EN_VW_SYSEVT1 | \
+ ESPI_INT_EN_VW_GPIOEVT | \
+ ESPI_INT_EN_VW_SYSEVT)
+
+#define ESPI_INT_EN_OOB_BITS \
+ (ESPI_INT_EN_OOB_RX_TMOUT | \
+ ESPI_INT_EN_OOB_TX_ERR | \
+ ESPI_INT_EN_OOB_TX_ABT | \
+ ESPI_INT_EN_OOB_RX_ABT | \
+ ESPI_INT_EN_OOB_TX_CMPLT | \
+ ESPI_INT_EN_OOB_RX_CMPLT)
+
+#define ESPI_INT_EN_FLASH_BITS \
+ (ESPI_INT_EN_FLASH_TX_ERR | \
+ ESPI_INT_EN_FLASH_TX_ABT | \
+ ESPI_INT_EN_FLASH_RX_ABT | \
+ ESPI_INT_EN_FLASH_TX_CMPLT | \
+ ESPI_INT_EN_FLASH_RX_CMPLT)
+
+#endif
diff --git a/drivers/soc/aspeed/aspeed-espi-flash.c b/drivers/soc/aspeed/aspeed-espi-flash.c
new file mode 100644
index 000000000000..d1ede22f22e3
--- /dev/null
+++ b/drivers/soc/aspeed/aspeed-espi-flash.c
@@ -0,0 +1,352 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright 2021 ASPEED Technology Inc.
+ */
+#include <linux/fs.h>
+#include <linux/of_device.h>
+#include <linux/miscdevice.h>
+#include <linux/mfd/syscon.h>
+#include <linux/regmap.h>
+#include <linux/uaccess.h>
+#include <linux/vmalloc.h>
+#include <linux/miscdevice.h>
+#include <linux/dma-mapping.h>
+
+#include "aspeed-espi-ioc.h"
+#include "aspeed-espi-ctrl.h"
+#include "aspeed-espi-flash.h"
+
+#define FLASH_MDEV_NAME "aspeed-espi-flash"
+
+static long aspeed_espi_flash_get_rx(struct file *fp,
+ struct aspeed_espi_ioc *ioc,
+ struct aspeed_espi_flash *espi_flash)
+{
+ int i, rc = 0;
+ unsigned long flags;
+ uint32_t reg;
+ uint32_t cyc, tag, len;
+ uint8_t *pkt;
+ uint32_t pkt_len;
+ struct espi_comm_hdr *hdr;
+ struct aspeed_espi_ctrl *espi_ctrl = espi_flash->ctrl;
+
+ if (fp->f_flags & O_NONBLOCK) {
+ if (mutex_trylock(&espi_flash->get_rx_mtx))
+ return -EBUSY;
+
+ if (!espi_flash->rx_ready) {
+ rc = -ENODATA;
+ goto unlock_mtx_n_out;
+ }
+ } else {
+ mutex_lock(&espi_flash->get_rx_mtx);
+
+ if (!espi_flash->rx_ready) {
+ rc = wait_event_interruptible(espi_flash->wq,
+ espi_flash->rx_ready);
+ if (rc == -ERESTARTSYS) {
+ rc = -EINTR;
+ goto unlock_mtx_n_out;
+ }
+ }
+ }
+
+ /* common header (i.e. cycle type, tag, and length) is taken by HW */
+ regmap_read(espi_ctrl->map, ESPI_FLASH_RX_CTRL, &reg);
+ cyc = (reg & ESPI_FLASH_RX_CTRL_CYC_MASK) >> ESPI_FLASH_RX_CTRL_CYC_SHIFT;
+ tag = (reg & ESPI_FLASH_RX_CTRL_TAG_MASK) >> ESPI_FLASH_RX_CTRL_TAG_SHIFT;
+ len = (reg & ESPI_FLASH_RX_CTRL_LEN_MASK) >> ESPI_FLASH_RX_CTRL_LEN_SHIFT;
+
+ /*
+ * calculate the length of the rest part of the
+ * eSPI packet to be read from HW and copied to
+ * user space.
+ */
+ switch (cyc) {
+ case ESPI_FLASH_READ:
+ case ESPI_FLASH_WRITE:
+ case ESPI_FLASH_ERASE:
+ pkt_len = ((len) ? len : ESPI_PLD_LEN_MAX) +
+ sizeof(struct espi_flash_rwe);
+ break;
+ case ESPI_FLASH_SUC_CMPLT_D_MIDDLE:
+ case ESPI_FLASH_SUC_CMPLT_D_FIRST:
+ case ESPI_FLASH_SUC_CMPLT_D_LAST:
+ case ESPI_FLASH_SUC_CMPLT_D_ONLY:
+ pkt_len = ((len) ? len : ESPI_PLD_LEN_MAX) +
+ sizeof(struct espi_flash_cmplt);
+ break;
+ case ESPI_FLASH_SUC_CMPLT:
+ case ESPI_FLASH_UNSUC_CMPLT:
+ pkt_len = len + sizeof(struct espi_flash_cmplt);
+ break;
+ default:
+ rc = -EFAULT;
+ goto unlock_mtx_n_out;
+ }
+
+ if (ioc->pkt_len < pkt_len) {
+ rc = -EINVAL;
+ goto unlock_mtx_n_out;
+ }
+
+ pkt = vmalloc(pkt_len);
+ if (!pkt) {
+ rc = -ENOMEM;
+ goto unlock_mtx_n_out;
+ }
+
+ hdr = (struct espi_comm_hdr *)pkt;
+ hdr->cyc = cyc;
+ hdr->tag = tag;
+ hdr->len_h = len >> 8;
+ hdr->len_l = len & 0xff;
+
+ if (espi_flash->dma_mode) {
+ memcpy(hdr + 1, espi_flash->dma.rx_virt,
+ pkt_len - sizeof(*hdr));
+ } else {
+ for (i = sizeof(*hdr); i < pkt_len; ++i) {
+ regmap_read(espi_ctrl->map,
+ ESPI_FLASH_RX_PORT, &reg);
+ pkt[i] = reg & 0xff;
+ }
+ }
+
+ if (copy_to_user((void __user *)ioc->pkt, pkt, pkt_len)) {
+ rc = -EFAULT;
+ goto free_n_out;
+ }
+
+ spin_lock_irqsave(&espi_flash->lock, flags);
+
+ regmap_write_bits(espi_ctrl->map, ESPI_FLASH_RX_CTRL,
+ ESPI_FLASH_RX_CTRL_PEND_SERV,
+ ESPI_FLASH_RX_CTRL_PEND_SERV);
+
+ espi_flash->rx_ready = 0;
+
+ spin_unlock_irqrestore(&espi_flash->lock, flags);
+
+free_n_out:
+ vfree(pkt);
+
+unlock_mtx_n_out:
+ mutex_unlock(&espi_flash->get_rx_mtx);
+
+ return rc;
+}
+
+static long aspeed_espi_flash_put_tx(struct file *fp,
+ struct aspeed_espi_ioc *ioc,
+ struct aspeed_espi_flash *espi_flash)
+{
+ int i, rc = 0;
+ uint32_t reg;
+ uint32_t cyc, tag, len;
+ uint8_t *pkt;
+ struct espi_comm_hdr *hdr;
+ struct aspeed_espi_ctrl *espi_ctrl = espi_flash->ctrl;
+
+ if (!mutex_trylock(&espi_flash->put_tx_mtx))
+ return -EAGAIN;
+
+ regmap_read(espi_ctrl->map, ESPI_FLASH_TX_CTRL, &reg);
+ if (reg & ESPI_FLASH_TX_CTRL_TRIGGER) {
+ rc = -EBUSY;
+ goto unlock_mtx_n_out;
+ }
+
+ pkt = vmalloc(ioc->pkt_len);
+ if (!pkt) {
+ rc = -ENOMEM;
+ goto unlock_mtx_n_out;
+ }
+
+ hdr = (struct espi_comm_hdr *)pkt;
+
+ if (copy_from_user(pkt, (void __user *)ioc->pkt, ioc->pkt_len)) {
+ rc = -EFAULT;
+ goto free_n_out;
+ }
+
+ /*
+ * common header (i.e. cycle type, tag, and length)
+ * part is written to HW registers
+ */
+ if (espi_flash->dma_mode) {
+ memcpy(espi_flash->dma.tx_virt, hdr + 1,
+ ioc->pkt_len - sizeof(*hdr));
+ dma_wmb();
+ } else {
+ for (i = sizeof(*hdr); i < ioc->pkt_len; ++i)
+ regmap_write(espi_ctrl->map,
+ ESPI_FLASH_TX_PORT, pkt[i]);
+ }
+
+ cyc = hdr->cyc;
+ tag = hdr->tag;
+ len = (hdr->len_h << 8) | (hdr->len_l & 0xff);
+
+ reg = ((cyc << ESPI_FLASH_TX_CTRL_CYC_SHIFT) & ESPI_FLASH_TX_CTRL_CYC_MASK)
+ | ((tag << ESPI_FLASH_TX_CTRL_TAG_SHIFT) & ESPI_FLASH_TX_CTRL_TAG_MASK)
+ | ((len << ESPI_FLASH_TX_CTRL_LEN_SHIFT) & ESPI_FLASH_TX_CTRL_LEN_MASK)
+ | ESPI_FLASH_TX_CTRL_TRIGGER;
+
+ regmap_write(espi_ctrl->map, ESPI_FLASH_TX_CTRL, reg);
+
+free_n_out:
+ vfree(pkt);
+
+unlock_mtx_n_out:
+ mutex_unlock(&espi_flash->put_tx_mtx);
+
+ return rc;
+}
+
+static long aspeed_espi_flash_ioctl(struct file *fp, unsigned int cmd, unsigned long arg)
+{
+ struct aspeed_espi_ioc ioc;
+ struct aspeed_espi_flash *espi_flash = container_of(
+ fp->private_data,
+ struct aspeed_espi_flash,
+ mdev);
+
+ if (copy_from_user(&ioc, (void __user *)arg, sizeof(ioc)))
+ return -EFAULT;
+
+ if (ioc.pkt_len > ESPI_PKT_LEN_MAX)
+ return -EINVAL;
+
+ switch (cmd) {
+ case ASPEED_ESPI_FLASH_GET_RX:
+ return aspeed_espi_flash_get_rx(fp, &ioc, espi_flash);
+ case ASPEED_ESPI_FLASH_PUT_TX:
+ return aspeed_espi_flash_put_tx(fp, &ioc, espi_flash);
+ };
+
+ return -EINVAL;
+}
+
+void aspeed_espi_flash_event(uint32_t sts, struct aspeed_espi_flash *espi_flash)
+{
+ unsigned long flags;
+
+ if (sts & ESPI_INT_STS_FLASH_RX_CMPLT) {
+ spin_lock_irqsave(&espi_flash->lock, flags);
+ espi_flash->rx_ready = 1;
+ spin_unlock_irqrestore(&espi_flash->lock, flags);
+ wake_up_interruptible(&espi_flash->wq);
+ }
+}
+
+void aspeed_espi_flash_enable(struct aspeed_espi_flash *espi_flash)
+{
+ struct aspeed_espi_flash_dma *dma = &espi_flash->dma;
+ struct aspeed_espi_ctrl *espi_ctrl = espi_flash->ctrl;
+
+ regmap_update_bits(espi_ctrl->map, ESPI_CTRL,
+ ESPI_CTRL_FLASH_SW_MODE_MASK,
+ (espi_flash->safs_mode << ESPI_CTRL_FLASH_SW_MODE_SHIFT));
+
+ if (espi_flash->dma_mode) {
+ regmap_write(espi_ctrl->map, ESPI_FLASH_TX_DMA, dma->tx_addr);
+ regmap_write(espi_ctrl->map, ESPI_FLASH_RX_DMA, dma->rx_addr);
+ regmap_update_bits(espi_ctrl->map, ESPI_CTRL,
+ ESPI_CTRL_FLASH_TX_DMA_EN | ESPI_CTRL_FLASH_RX_DMA_EN,
+ ESPI_CTRL_FLASH_TX_DMA_EN | ESPI_CTRL_FLASH_RX_DMA_EN);
+ }
+
+ regmap_write(espi_ctrl->map, ESPI_INT_STS,
+ ESPI_INT_STS_FLASH_BITS);
+
+ regmap_update_bits(espi_ctrl->map, ESPI_INT_EN,
+ ESPI_INT_EN_FLASH_BITS,
+ ESPI_INT_EN_FLASH_BITS);
+
+ regmap_update_bits(espi_ctrl->map, ESPI_CTRL,
+ ESPI_CTRL_FLASH_SW_RDY,
+ ESPI_CTRL_FLASH_SW_RDY);
+}
+
+static const struct file_operations aspeed_espi_flash_fops = {
+ .owner = THIS_MODULE,
+ .unlocked_ioctl = aspeed_espi_flash_ioctl,
+};
+
+void *aspeed_espi_flash_alloc(struct device *dev, struct aspeed_espi_ctrl *espi_ctrl)
+{
+ int rc = 0;
+ struct aspeed_espi_flash *espi_flash;
+ struct aspeed_espi_flash_dma *dma;
+
+ espi_flash = devm_kzalloc(dev, sizeof(*espi_flash), GFP_KERNEL);
+ if (!espi_flash)
+ return ERR_PTR(-ENOMEM);
+
+ espi_flash->ctrl = espi_ctrl;
+
+ init_waitqueue_head(&espi_flash->wq);
+
+ spin_lock_init(&espi_flash->lock);
+
+ mutex_init(&espi_flash->put_tx_mtx);
+ mutex_init(&espi_flash->get_rx_mtx);
+
+ if (of_property_read_bool(dev->of_node, "flash,dma-mode"))
+ espi_flash->dma_mode = 1;
+
+ of_property_read_u32(dev->of_node, "flash,safs-mode", &espi_flash->safs_mode);
+ if (espi_flash->safs_mode >= SAFS_MODES) {
+ dev_err(dev, "invalid SAFS mode\n");
+ return ERR_PTR(-EINVAL);
+ }
+
+ if (espi_flash->dma_mode) {
+ dma = &espi_flash->dma;
+
+ dma->tx_virt = dma_alloc_coherent(dev, PAGE_SIZE,
+ &dma->tx_addr, GFP_KERNEL);
+ if (!dma->tx_virt) {
Here and a few lines below, dma_alloc_coherent() could be replaced by dmam_alloc_coherent() (its managed version) to simplify error handling and freeing of resources.

+ dev_err(dev, "cannot allocate DMA TX buffer\n");
+ return ERR_PTR(-ENOMEM);
+ }
+
+ dma->rx_virt = dma_alloc_coherent(dev, PAGE_SIZE,
+ &dma->rx_addr, GFP_KERNEL);
+ if (!dma->rx_virt) {
+ dev_err(dev, "cannot allocate DMA RX buffer\n");
+ return ERR_PTR(-ENOMEM);
+ }
+ }
+
+ espi_flash->mdev.parent = dev;
+ espi_flash->mdev.minor = MISC_DYNAMIC_MINOR;
+ espi_flash->mdev.name = devm_kasprintf(dev, GFP_KERNEL, "%s", FLASH_MDEV_NAME);
+ espi_flash->mdev.fops = &aspeed_espi_flash_fops;
+ rc = misc_register(&espi_flash->mdev);
+ if (rc) {
+ dev_err(dev, "cannot register device\n");
+ return ERR_PTR(rc);
+ }
+
+ aspeed_espi_flash_enable(espi_flash);
+
+ return espi_flash;
+}
+
+void aspeed_espi_flash_free(struct device *dev, struct aspeed_espi_flash *espi_flash)
+{
+ struct aspeed_espi_flash_dma *dma = &espi_flash->dma;
+
+ if (espi_flash->dma_mode) {
+ dma_free_coherent(dev, PAGE_SIZE, dma->tx_virt, dma->tx_addr);
+ dma_free_coherent(dev, PAGE_SIZE, dma->rx_virt, dma->rx_addr);
+ }
+
+ mutex_destroy(&espi_flash->put_tx_mtx);
+ mutex_destroy(&espi_flash->get_rx_mtx);
+
+ misc_deregister(&espi_flash->mdev);
+}
diff --git a/drivers/soc/aspeed/aspeed-espi-flash.h b/drivers/soc/aspeed/aspeed-espi-flash.h
new file mode 100644
index 000000000000..bd5177329e50
--- /dev/null
+++ b/drivers/soc/aspeed/aspeed-espi-flash.h
@@ -0,0 +1,45 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Copyright 2021 ASPEED Technology Inc.
+ */
+#ifndef _ASPEED_ESPI_FLASH_H_
+#define _ASPEED_ESPI_FLASH_H_
+
+enum aspeed_espi_flash_safs_mode {
+ SAFS_MODE_MIX,
+ SAFS_MODE_SW,
+ SAFS_MODE_HW,
+ SAFS_MODES,
+};
+
+struct aspeed_espi_flash_dma {
+ void *tx_virt;
+ dma_addr_t tx_addr;
+ void *rx_virt;
+ dma_addr_t rx_addr;
+};
+
+struct aspeed_espi_flash {
+ uint32_t safs_mode;
+
+ uint32_t dma_mode;
+ struct aspeed_espi_flash_dma dma;
+
+ uint32_t rx_ready;
+ wait_queue_head_t wq;
+
+ struct mutex get_rx_mtx;
+ struct mutex put_tx_mtx;
+
+ spinlock_t lock;
+
+ struct miscdevice mdev;
+ struct aspeed_espi_ctrl *ctrl;
+};
+
+void aspeed_espi_flash_event(uint32_t sts, struct aspeed_espi_flash *espi_flash);
+void aspeed_espi_flash_enable(struct aspeed_espi_flash *espi_flash);
+void *aspeed_espi_flash_alloc(struct device *dev, struct aspeed_espi_ctrl *espi_ctrl);
+void aspeed_espi_flash_free(struct device *dev, struct aspeed_espi_flash *espi_flash);
+
+#endif
diff --git a/drivers/soc/aspeed/aspeed-espi-ioc.h b/drivers/soc/aspeed/aspeed-espi-ioc.h
new file mode 100644
index 000000000000..a78f1069841f
--- /dev/null
+++ b/drivers/soc/aspeed/aspeed-espi-ioc.h
@@ -0,0 +1,195 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Copyright 2021 Aspeed Technology Inc.
+ */
+#ifndef _ASPEED_ESPI_IOC_H
+#define _ASPEED_ESPI_IOC_H
+
+#include <linux/ioctl.h>
+#include <linux/types.h>
+
+/*
+ * eSPI cycle type encoding
+ *
+ * Section 5.1 Cycle Types and Packet Format,
+ * Intel eSPI Interface Base Specification, Rev 1.0, Jan. 2016.
+ */
+#define ESPI_PERIF_MEMRD32 0x00
+#define ESPI_PERIF_MEMRD64 0x02
+#define ESPI_PERIF_MEMWR32 0x01
+#define ESPI_PERIF_MEMWR64 0x03
+#define ESPI_PERIF_MSG 0x10
+#define ESPI_PERIF_MSG_D 0x11
+#define ESPI_PERIF_SUC_CMPLT 0x06
+#define ESPI_PERIF_SUC_CMPLT_D_MIDDLE 0x09
+#define ESPI_PERIF_SUC_CMPLT_D_FIRST 0x0b
+#define ESPI_PERIF_SUC_CMPLT_D_LAST 0x0d
+#define ESPI_PERIF_SUC_CMPLT_D_ONLY 0x0f
+#define ESPI_PERIF_UNSUC_CMPLT 0x0c
+#define ESPI_OOB_MSG 0x21
+#define ESPI_FLASH_READ 0x00
+#define ESPI_FLASH_WRITE 0x01
+#define ESPI_FLASH_ERASE 0x02
+#define ESPI_FLASH_SUC_CMPLT 0x06
+#define ESPI_FLASH_SUC_CMPLT_D_MIDDLE 0x09
+#define ESPI_FLASH_SUC_CMPLT_D_FIRST 0x0b
+#define ESPI_FLASH_SUC_CMPLT_D_LAST 0x0d
+#define ESPI_FLASH_SUC_CMPLT_D_ONLY 0x0f
+#define ESPI_FLASH_UNSUC_CMPLT 0x0c
+
+/*
+ * eSPI packet format structure
+ *
+ * Section 5.1 Cycle Types and Packet Format,
+ * Intel eSPI Interface Base Specification, Rev 1.0, Jan. 2016.
+ */
+struct espi_comm_hdr {
+ uint8_t cyc;
+ uint8_t len_h : 4;
+ uint8_t tag : 4;
+ uint8_t len_l;
+};
+
+struct espi_perif_mem32 {
+ uint8_t cyc;
+ uint8_t len_h : 4;
+ uint8_t tag : 4;
+ uint8_t len_l;
+ uint32_t addr_be;
+ uint8_t data[];
+} __packed;
+
+struct espi_perif_mem64 {
+ uint8_t cyc;
+ uint8_t len_h : 4;
+ uint8_t tag : 4;
+ uint8_t len_l;
+ uint32_t addr_be;
+ uint8_t data[];
+} __packed;
+
+struct espi_perif_msg {
+ uint8_t cyc;
+ uint8_t len_h : 4;
+ uint8_t tag : 4;
+ uint8_t len_l;
+ uint8_t msg_code;
+ uint8_t msg_byte[4];
+ uint8_t data[];
+} __packed;
+
+struct espi_perif_cmplt {
+ uint8_t cyc;
+ uint8_t len_h : 4;
+ uint8_t tag : 4;
+ uint8_t len_l;
+ uint8_t data[];
+} __packed;
+
+struct espi_oob_msg {
+ uint8_t cyc;
+ uint8_t len_h : 4;
+ uint8_t tag : 4;
+ uint8_t len_l;
+ uint8_t data[];
+};
+
+struct espi_flash_rwe {
+ uint8_t cyc;
+ uint8_t len_h : 4;
+ uint8_t tag : 4;
+ uint8_t len_l;
+ uint32_t addr_be;
+ uint8_t data[];
+} __packed;
+
+struct espi_flash_cmplt {
+ uint8_t cyc;
+ uint8_t len_h : 4;
+ uint8_t tag : 4;
+ uint8_t len_l;
+ uint8_t data[];
+} __packed;
+
+struct aspeed_espi_ioc {
+ uint32_t pkt_len;
+ uint8_t *pkt;
+};
+
+/*
+ * we choose the longest header and the max payload size
+ * based on the Intel specification to define the maximum
+ * eSPI packet length
+ */
+#define ESPI_PLD_LEN_MIN (1UL << 6)
+#define ESPI_PLD_LEN_MAX (1UL << 12)
+#define ESPI_PKT_LEN_MAX (sizeof(struct espi_perif_msg) + ESPI_PLD_LEN_MAX)
+
+#define __ASPEED_ESPI_IOCTL_MAGIC 0xb8
+
+/*
+ * The IOCTL-based interface works in the eSPI packet in/out paradigm.
+ *
+ * Only the virtual wire IOCTL is a special case which does not send
+ * or receive an eSPI packet. However, to keep a more consisten use from
+ * userspace, we make all of the four channel drivers serve through the
+ * IOCTL interface.
+ *
+ * For the eSPI packet format, refer to
+ * Section 5.1 Cycle Types and Packet Format,
+ * Intel eSPI Interface Base Specification, Rev 1.0, Jan. 2016.
+ *
+ * For the example user apps using these IOCTL, refer to
+ * https://github.com/AspeedTech-BMC/aspeed_app/tree/master/espi_test
+ */
+
+/*
+ * Peripheral Channel (CH0)
+ * - ASPEED_ESPI_PERIF_PC_GET_RX
+ * Receive an eSPI Posted/Completion packet
+ * - ASPEED_ESPI_PERIF_PC_PUT_TX
+ * Transmit an eSPI Posted/Completion packet
+ * - ASPEED_ESPI_PERIF_NP_PUT_TX
+ * Transmit an eSPI Non-Posted packet
+ */
+#define ASPEED_ESPI_PERIF_PC_GET_RX _IOR(__ASPEED_ESPI_IOCTL_MAGIC, \
+ 0x00, struct aspeed_espi_ioc)
+#define ASPEED_ESPI_PERIF_PC_PUT_TX _IOW(__ASPEED_ESPI_IOCTL_MAGIC, \
+ 0x01, struct aspeed_espi_ioc)
+#define ASPEED_ESPI_PERIF_NP_PUT_TX _IOW(__ASPEED_ESPI_IOCTL_MAGIC, \
+ 0x02, struct aspeed_espi_ioc)
+/*
+ * Virtual Wire Channel (CH1)
+ * - ASPEED_ESPI_VW_GET_GPIO_VAL
+ * Read the input value of GPIO over the VW channel
+ * - ASPEED_ESPI_VW_PUT_GPIO_VAL
+ * Write the output value of GPIO over the VW channel
+ */
+#define ASPEED_ESPI_VW_GET_GPIO_VAL _IOR(__ASPEED_ESPI_IOCTL_MAGIC, \
+ 0x10, uint8_t)
+#define ASPEED_ESPI_VW_PUT_GPIO_VAL _IOW(__ASPEED_ESPI_IOCTL_MAGIC, \
+ 0x11, uint8_t)
+/*
+ * Out-of-band Channel (CH2)
+ * - ASPEED_ESPI_OOB_GET_RX
+ * Receive an eSPI OOB packet
+ * - ASPEED_ESPI_OOB_PUT_TX
+ * Transmit an eSPI OOB packet
+ */
+#define ASPEED_ESPI_OOB_GET_RX _IOR(__ASPEED_ESPI_IOCTL_MAGIC, \
+ 0x20, struct aspeed_espi_ioc)
+#define ASPEED_ESPI_OOB_PUT_TX _IOW(__ASPEED_ESPI_IOCTL_MAGIC, \
+ 0x21, struct aspeed_espi_ioc)
+/*
+ * Flash Channel (CH3)
+ * - ASPEED_ESPI_FLASH_GET_RX
+ * Receive an eSPI flash packet
+ * - ASPEED_ESPI_FLASH_PUT_TX
+ * Transmit an eSPI flash packet
+ */
+#define ASPEED_ESPI_FLASH_GET_RX _IOR(__ASPEED_ESPI_IOCTL_MAGIC, \
+ 0x30, struct aspeed_espi_ioc)
+#define ASPEED_ESPI_FLASH_PUT_TX _IOW(__ASPEED_ESPI_IOCTL_MAGIC, \
+ 0x31, struct aspeed_espi_ioc)
+
+#endif
diff --git a/drivers/soc/aspeed/aspeed-espi-oob.c b/drivers/soc/aspeed/aspeed-espi-oob.c
new file mode 100644
index 000000000000..2e0cc427b6c1
--- /dev/null
+++ b/drivers/soc/aspeed/aspeed-espi-oob.c
@@ -0,0 +1,558 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright 2021 Aspeed Technology Inc.
+ */
+#include <linux/fs.h>
+#include <linux/of_device.h>
+#include <linux/miscdevice.h>
+#include <linux/mfd/syscon.h>
+#include <linux/regmap.h>
+#include <linux/uaccess.h>
+#include <linux/vmalloc.h>
+#include <linux/miscdevice.h>
+#include <linux/dma-mapping.h>
+
+#include "aspeed-espi-ioc.h"
+#include "aspeed-espi-ctrl.h"
+#include "aspeed-espi-oob.h"
+
+#define OOB_MDEV_NAME "aspeed-espi-oob"
+
+/* DMA descriptor is supported since AST2600 */
+#define OOB_DMA_DESC_MAX_NUM 1024
+#define OOB_DMA_TX_DESC_CUST 0x04
+
+/* descriptor-based RX DMA handling */
+static long aspeed_espi_oob_dma_desc_get_rx(struct file *fp,
+ struct aspeed_espi_ioc *ioc,
+ struct aspeed_espi_oob *espi_oob)
+{
+ int rc = 0;
+ unsigned long flags;
+ uint32_t reg;
+ uint32_t wptr, sptr;
+ uint8_t *pkt;
+ uint32_t pkt_len;
+ struct espi_comm_hdr *hdr;
+ struct oob_rx_dma_desc *d;
+ struct aspeed_espi_ctrl *espi_ctrl = espi_oob->ctrl;
+
+ regmap_read(espi_ctrl->map, ESPI_OOB_RX_DMA_WS_PTR, &reg);
+ wptr = (reg & ESPI_OOB_RX_DMA_WS_PTR_WP_MASK) >> ESPI_OOB_RX_DMA_WS_PTR_WP_SHIFT;
+ sptr = (reg & ESPI_OOB_RX_DMA_WS_PTR_SP_MASK) >> ESPI_OOB_RX_DMA_WS_PTR_SP_SHIFT;
+
+ d = &espi_oob->dma.rx_desc[sptr];
+
+ if (!d->dirty)
+ return -EFAULT;
+
+ pkt_len = ((d->len) ? d->len : 0x1000) + sizeof(struct espi_comm_hdr);
+
+ if (ioc->pkt_len < pkt_len)
+ return -EINVAL;
+
+ pkt = vmalloc(pkt_len);
+ if (!pkt)
+ return -ENOMEM;
+
+ hdr = (struct espi_comm_hdr *)pkt;
+ hdr->cyc = d->cyc;
+ hdr->tag = d->tag;
+ hdr->len_h = d->len >> 8;
+ hdr->len_l = d->len & 0xff;
+ memcpy(hdr + 1, espi_oob->dma.rx_virt + (PAGE_SIZE * sptr), pkt_len - sizeof(*hdr));
+
+ if (copy_to_user((void __user *)ioc->pkt, pkt, pkt_len)) {
+ rc = -EFAULT;
+ goto free_n_out;
+ }
+
+ spin_lock_irqsave(&espi_oob->lock, flags);
+
+ /* make current descriptor available again */
+ d->dirty = 0;
+
+ sptr = (sptr + 1) % espi_oob->dma.rx_desc_num;
+ wptr = (wptr + 1) % espi_oob->dma.rx_desc_num;
+
+ reg = ((wptr << ESPI_OOB_RX_DMA_WS_PTR_WP_SHIFT) & ESPI_OOB_RX_DMA_WS_PTR_WP_MASK)
+ | ((sptr << ESPI_OOB_RX_DMA_WS_PTR_SP_SHIFT) & ESPI_OOB_RX_DMA_WS_PTR_SP_MASK)
+ | ESPI_OOB_RX_DMA_WS_PTR_RECV_EN;
+ regmap_write(espi_ctrl->map, ESPI_OOB_RX_DMA_WS_PTR, reg);
+
+ /* set ready flag base on the next RX descriptor */
+ espi_oob->rx_ready = espi_oob->dma.rx_desc[sptr].dirty;
+
+ spin_unlock_irqrestore(&espi_oob->lock, flags);
+
+free_n_out:
+ vfree(pkt);
+
+ return rc;
+}
+
+static long aspeed_espi_oob_get_rx(struct file *fp,
+ struct aspeed_espi_ioc *ioc,
+ struct aspeed_espi_oob *espi_oob)
+{
+ int i, rc = 0;
+ unsigned long flags;
+ uint32_t reg;
+ uint32_t cyc, tag, len;
+ uint8_t *pkt;
+ uint32_t pkt_len;
+ struct espi_comm_hdr *hdr;
+ struct aspeed_espi_ctrl *espi_ctrl = espi_oob->ctrl;
+
+ if (fp->f_flags & O_NONBLOCK) {
+ if (mutex_trylock(&espi_oob->get_rx_mtx))
+ return -EBUSY;
+
+ if (!espi_oob->rx_ready) {
+ rc = -ENODATA;
+ goto unlock_mtx_n_out;
+ }
+ } else {
+ mutex_lock(&espi_oob->get_rx_mtx);
+
+ if (!espi_oob->rx_ready) {
+ rc = wait_event_interruptible(espi_oob->wq,
+ espi_oob->rx_ready);
+ if (rc == -ERESTARTSYS) {
+ rc = -EINTR;
+ goto unlock_mtx_n_out;
+ }
+ }
+ }
+
+ if (espi_oob->dma_mode && espi_ctrl->model->version != ESPI_AST2500) {
+ rc = aspeed_espi_oob_dma_desc_get_rx(fp, ioc, espi_oob);
+ goto unlock_mtx_n_out;
+ }
+
+ /* common header (i.e. cycle type, tag, and length) is taken by HW */
+ regmap_read(espi_ctrl->map, ESPI_OOB_RX_CTRL, &reg);
+ cyc = (reg & ESPI_OOB_RX_CTRL_CYC_MASK) >> ESPI_OOB_RX_CTRL_CYC_SHIFT;
+ tag = (reg & ESPI_OOB_RX_CTRL_TAG_MASK) >> ESPI_OOB_RX_CTRL_TAG_SHIFT;
+ len = (reg & ESPI_OOB_RX_CTRL_LEN_MASK) >> ESPI_OOB_RX_CTRL_LEN_SHIFT;
+
+ /*
+ * calculate the length of the rest part of the
+ * eSPI packet to be read from HW and copied to
+ * user space.
+ */
+ pkt_len = ((len) ? len : ESPI_PLD_LEN_MAX) + sizeof(struct espi_comm_hdr);
+
+ if (ioc->pkt_len < pkt_len) {
+ rc = -EINVAL;
+ goto unlock_mtx_n_out;
+ }
+
+ pkt = vmalloc(pkt_len);
+ if (!pkt) {
+ rc = -ENOMEM;
+ goto unlock_mtx_n_out;
+ }
+
+ hdr = (struct espi_comm_hdr *)pkt;
+ hdr->cyc = cyc;
+ hdr->tag = tag;
+ hdr->len_h = len >> 8;
+ hdr->len_l = len & 0xff;
+
+ if (espi_oob->dma_mode) {
+ memcpy(hdr + 1, espi_oob->dma.rx_virt,
+ pkt_len - sizeof(*hdr));
+ } else {
+ for (i = sizeof(*hdr); i < pkt_len; ++i) {
+ regmap_read(espi_ctrl->map,
+ ESPI_OOB_RX_PORT, &reg);
+ pkt[i] = reg & 0xff;
+ }
+ }
+
+ if (copy_to_user((void __user *)ioc->pkt, pkt, pkt_len)) {
+ rc = -EFAULT;
+ goto free_n_out;
+ }
+
+ spin_lock_irqsave(&espi_oob->lock, flags);
+
+ regmap_write_bits(espi_ctrl->map, ESPI_OOB_RX_CTRL,
+ ESPI_OOB_RX_CTRL_PEND_SERV,
+ ESPI_OOB_RX_CTRL_PEND_SERV);
+
+ espi_oob->rx_ready = 0;
+
+ spin_unlock_irqrestore(&espi_oob->lock, flags);
+
+free_n_out:
+ vfree(pkt);
+
+unlock_mtx_n_out:
+ mutex_unlock(&espi_oob->get_rx_mtx);
+
+ return rc;
+}
+
+/* descriptor-based TX DMA handling */
+static long aspeed_espi_oob_dma_desc_put_tx(struct file *fp,
+ struct aspeed_espi_ioc *ioc,
+ struct aspeed_espi_oob *espi_oob)
+{
+ int rc = 0;
+ uint32_t rptr, wptr;
+ uint8_t *pkt;
+ struct espi_comm_hdr *hdr;
+ struct oob_tx_dma_desc *d;
+ struct aspeed_espi_ctrl *espi_ctrl = espi_oob->ctrl;
+
+ pkt = vzalloc(ioc->pkt_len);
+ if (!pkt)
+ return -ENOMEM;
+
+ hdr = (struct espi_comm_hdr *)pkt;
+
+ if (copy_from_user(pkt, (void __user *)ioc->pkt, ioc->pkt_len)) {
+ rc = -EFAULT;
+ goto free_n_out;
+ }
+
+ /* kick HW to reflect the up-to-date read/write pointer */
+ regmap_write(espi_ctrl->map, ESPI_OOB_TX_DMA_RD_PTR,
+ ESPI_OOB_TX_DMA_RD_PTR_UPDATE);
+
+ regmap_read(espi_ctrl->map, ESPI_OOB_TX_DMA_RD_PTR, &rptr);
+ regmap_read(espi_ctrl->map, ESPI_OOB_TX_DMA_WR_PTR, &wptr);
+
+ if (((wptr + 1) % espi_oob->dma.tx_desc_num) == rptr) {
+ rc = -EBUSY;
+ goto free_n_out;
+ }
+
+ d = &espi_oob->dma.tx_desc[wptr];
+ d->cyc = hdr->cyc;
+ d->tag = hdr->tag;
+ d->len = (hdr->len_h << 8) | (hdr->len_l & 0xff);
+ d->msg_type = OOB_DMA_TX_DESC_CUST;
+
+ memcpy(espi_oob->dma.tx_virt + (PAGE_SIZE * wptr), hdr + 1,
+ ioc->pkt_len - sizeof(*hdr));
+
+ dma_wmb();
+
+ wptr = (wptr + 1) % espi_oob->dma.tx_desc_num;
+ wptr |= ESPI_OOB_TX_DMA_WR_PTR_SEND_EN;
+ regmap_write(espi_ctrl->map, ESPI_OOB_TX_DMA_WR_PTR, wptr);
+
+free_n_out:
+ vfree(pkt);
+
+ return rc;
+}
+
+static long aspeed_espi_oob_put_tx(struct file *fp,
+ struct aspeed_espi_ioc *ioc,
+ struct aspeed_espi_oob *espi_oob)
+{
+ int i, rc = 0;
+ uint32_t reg;
+ uint32_t cyc, tag, len;
+ uint8_t *pkt;
+ struct espi_comm_hdr *hdr;
+ struct aspeed_espi_ctrl *espi_ctrl = espi_oob->ctrl;
+
+ if (!mutex_trylock(&espi_oob->put_tx_mtx))
+ return -EBUSY;
+
+ if (espi_oob->dma_mode && espi_ctrl->model->version != ESPI_AST2500) {
+ rc = aspeed_espi_oob_dma_desc_put_tx(fp, ioc, espi_oob);
+ goto unlock_mtx_n_out;
+ }
+
+ regmap_read(espi_ctrl->map, ESPI_OOB_TX_CTRL, &reg);
+ if (reg & ESPI_OOB_TX_CTRL_TRIGGER) {
+ rc = -EBUSY;
+ goto unlock_mtx_n_out;
+ }
+
+ if (ioc->pkt_len > ESPI_PKT_LEN_MAX) {
+ rc = -EINVAL;
+ goto unlock_mtx_n_out;
+ }
+
+ pkt = vmalloc(ioc->pkt_len);
+ if (!pkt) {
+ rc = -ENOMEM;
+ goto unlock_mtx_n_out;
+ }
+
+ hdr = (struct espi_comm_hdr *)pkt;
+
+ if (copy_from_user(pkt, (void __user *)ioc->pkt, ioc->pkt_len)) {
+ rc = -EFAULT;
+ goto free_n_out;
+ }
+
+ /*
+ * common header (i.e. cycle type, tag, and length)
+ * part is written to HW registers
+ */
+ if (espi_oob->dma_mode) {
+ memcpy(espi_oob->dma.tx_virt, hdr + 1,
+ ioc->pkt_len - sizeof(*hdr));
+ dma_wmb();
+ } else {
+ for (i = sizeof(*hdr); i < ioc->pkt_len; ++i)
+ regmap_write(espi_ctrl->map,
+ ESPI_OOB_TX_PORT, pkt[i]);
+ }
+
+ cyc = hdr->cyc;
+ tag = hdr->tag;
+ len = (hdr->len_h << 8) | (hdr->len_l & 0xff);
+
+ reg = ((cyc << ESPI_OOB_TX_CTRL_CYC_SHIFT) & ESPI_OOB_TX_CTRL_CYC_MASK)
+ | ((tag << ESPI_OOB_TX_CTRL_TAG_SHIFT) & ESPI_OOB_TX_CTRL_TAG_MASK)
+ | ((len << ESPI_OOB_TX_CTRL_LEN_SHIFT) & ESPI_OOB_TX_CTRL_LEN_MASK)
+ | ESPI_OOB_TX_CTRL_TRIGGER;
+
+ regmap_write(espi_ctrl->map, ESPI_OOB_TX_CTRL, reg);
+
+free_n_out:
+ vfree(pkt);
+
+unlock_mtx_n_out:
+ mutex_unlock(&espi_oob->put_tx_mtx);
+
+ return rc;
+}
+
+static long aspeed_espi_oob_ioctl(struct file *fp, unsigned int cmd, unsigned long arg)
+{
+ struct aspeed_espi_ioc ioc;
+ struct aspeed_espi_oob *espi_oob = container_of(
+ fp->private_data,
+ struct aspeed_espi_oob,
+ mdev);
+
+ if (copy_from_user(&ioc, (void __user *)arg, sizeof(ioc)))
+ return -EFAULT;
+
+ if (ioc.pkt_len > ESPI_PKT_LEN_MAX)
+ return -EINVAL;
+
+ switch (cmd) {
+ case ASPEED_ESPI_OOB_GET_RX:
+ return aspeed_espi_oob_get_rx(fp, &ioc, espi_oob);
+ case ASPEED_ESPI_OOB_PUT_TX:
+ return aspeed_espi_oob_put_tx(fp, &ioc, espi_oob);
+ };
+
+ return -EINVAL;
+}
+
+void aspeed_espi_oob_event(uint32_t sts, struct aspeed_espi_oob *espi_oob)
+{
+ unsigned long flags;
+
+ if (sts & ESPI_INT_STS_OOB_RX_CMPLT) {
+ spin_lock_irqsave(&espi_oob->lock, flags);
+ espi_oob->rx_ready = 1;
+ spin_unlock_irqrestore(&espi_oob->lock, flags);
+
+ wake_up_interruptible(&espi_oob->wq);
+ }
+}
+
+void aspeed_espi_oob_enable(struct aspeed_espi_oob *espi_oob)
+{
+ int i;
+ struct aspeed_espi_oob_dma *dma = &espi_oob->dma;
+ struct aspeed_espi_ctrl *espi_ctrl = espi_oob->ctrl;
+
+ regmap_update_bits(espi_ctrl->map, ESPI_CTRL,
+ ESPI_CTRL_OOB_SW_RDY | ESPI_CTRL_OOB_RX_SW_RST, 0);
+
+ if (espi_oob->dma_mode)
+ regmap_update_bits(espi_ctrl->map, ESPI_CTRL,
+ ESPI_CTRL_OOB_TX_DMA_EN | ESPI_CTRL_OOB_RX_DMA_EN, 0);
+ else
+ regmap_write(espi_ctrl->map, ESPI_OOB_RX_CTRL, ESPI_OOB_RX_CTRL_PEND_SERV);
+
+ /*
+ * cleanup OOB RX FIFO to get rid of the data
+ * of OOB early init side-effect
+ */
+ regmap_update_bits(espi_ctrl->map, ESPI_CTRL,
+ ESPI_CTRL_OOB_RX_SW_RST, ESPI_CTRL_OOB_RX_SW_RST);
+
+ regmap_write(espi_ctrl->map, ESPI_OOB_RX_CTRL,
+ ESPI_OOB_RX_CTRL_PEND_SERV);
+
+ if (espi_oob->dma_mode) {
+ regmap_update_bits(espi_ctrl->map, ESPI_CTRL,
+ ESPI_CTRL_OOB_TX_DMA_EN | ESPI_CTRL_OOB_RX_DMA_EN,
+ ESPI_CTRL_OOB_TX_DMA_EN | ESPI_CTRL_OOB_RX_DMA_EN);
+
+ if (espi_ctrl->model->version == ESPI_AST2500) {
+ regmap_write(espi_ctrl->map, ESPI_OOB_TX_DMA, dma->tx_addr);
+ regmap_write(espi_ctrl->map, ESPI_OOB_RX_DMA, dma->rx_addr);
+ } else {
+ for (i = 0; i < dma->tx_desc_num; ++i)
+ dma->tx_desc[i].data_addr = dma->tx_addr + (i * PAGE_SIZE);
+
+ for (i = 0; i < dma->rx_desc_num; ++i) {
+ dma->rx_desc[i].data_addr = dma->rx_addr + (i * PAGE_SIZE);
+ dma->rx_desc[i].dirty = 0;
+ }
+
+ regmap_write(espi_ctrl->map, ESPI_OOB_TX_DMA, dma->tx_desc_addr);
+ regmap_write(espi_ctrl->map, ESPI_OOB_TX_DMA_RB_SIZE, dma->tx_desc_num);
+
+ regmap_write(espi_ctrl->map, ESPI_OOB_RX_DMA, dma->rx_desc_addr);
+ regmap_write(espi_ctrl->map, ESPI_OOB_RX_DMA_RB_SIZE, dma->rx_desc_num);
+ regmap_update_bits(espi_ctrl->map, ESPI_OOB_RX_DMA_WS_PTR,
+ ESPI_OOB_RX_DMA_WS_PTR_RECV_EN,
+ ESPI_OOB_RX_DMA_WS_PTR_RECV_EN);
+ }
+ }
+
+ regmap_write(espi_ctrl->map, ESPI_INT_STS,
+ ESPI_INT_STS_OOB_BITS);
+
+ regmap_update_bits(espi_ctrl->map, ESPI_INT_EN,
+ ESPI_INT_EN_OOB_BITS,
+ ESPI_INT_EN_OOB_BITS);
+
+ regmap_update_bits(espi_ctrl->map, ESPI_CTRL,
+ ESPI_CTRL_OOB_SW_RDY,
+ ESPI_CTRL_OOB_SW_RDY);
+}
+
+static const struct file_operations aspeed_espi_oob_fops = {
+ .owner = THIS_MODULE,
+ .unlocked_ioctl = aspeed_espi_oob_ioctl,
+};
+
+void *aspeed_espi_oob_alloc(struct device *dev, struct aspeed_espi_ctrl *espi_ctrl)
+{
+ int rc = 0;
+ struct aspeed_espi_oob *espi_oob;
+ struct aspeed_espi_oob_dma *dma;
+
+ espi_oob = devm_kzalloc(dev, sizeof(*espi_oob), GFP_KERNEL);
+ if (!espi_oob)
+ return ERR_PTR(-ENOMEM);
+
+ espi_oob->ctrl = espi_ctrl;
+
+ init_waitqueue_head(&espi_oob->wq);
+
+ spin_lock_init(&espi_oob->lock);
+
+ mutex_init(&espi_oob->put_tx_mtx);
+ mutex_init(&espi_oob->get_rx_mtx);
+
+ if (of_property_read_bool(dev->of_node, "oob,dma-mode"))
+ espi_oob->dma_mode = 1;
+
+ if (espi_oob->dma_mode) {
+ dma = &espi_oob->dma;
+
+ /* Descriptor based OOB DMA is supported since AST2600 */
+ if (espi_ctrl->model->version != ESPI_AST2500) {
+ of_property_read_u32(dev->of_node, "oob,dma-tx-desc-num",
+ &dma->tx_desc_num);
+ of_property_read_u32(dev->of_node, "oob,dma-rx-desc-num",
+ &dma->rx_desc_num);
+
+ if (!dma->tx_desc_num || !dma->rx_desc_num) {
+ dev_err(dev, "invalid zero number of DMA channels\n");
+ return ERR_PTR(-EINVAL);
+ }
+
+ if (dma->tx_desc_num >= OOB_DMA_DESC_MAX_NUM ||
+ dma->rx_desc_num >= OOB_DMA_DESC_MAX_NUM) {
+ dev_err(dev, "too many number of DMA channels\n");
+ return ERR_PTR(-EINVAL);
+ }
+
+ dma->tx_desc = dma_alloc_coherent(dev,
+ sizeof(*dma->tx_desc) * dma->tx_desc_num,
+ &dma->tx_desc_addr, GFP_KERNEL);

Here and a few lines below, dma_alloc_coherent() could be replaced by dmam_alloc_coherent() (its managed version) to simplify error handling and freeing of resources.

+ if (!dma->tx_desc) {
+ dev_err(dev, "cannot allocate DMA TX descriptor\n");
+ return ERR_PTR(-ENOMEM);
+ }
+
+ dma->rx_desc = dma_alloc_coherent(dev,
+ sizeof(*dma->rx_desc) * dma->rx_desc_num,
+ &dma->rx_desc_addr, GFP_KERNEL);
+ if (!dma->rx_desc) {
+ dev_err(dev, "cannot allocate DMA RX descriptor\n");
+ return ERR_PTR(-ENOMEM);
+ }
+ }
+
+ /*
+ * DMA descriptors are consumed in the circular
+ * queue paradigm. Therefore, one dummy slot is
+ * reserved to detect the full condition.
+ *
+ * For AST2500 without DMA descriptors supported,
+ * the number of the queue slot should be 1 here.
+ */
+ dma->tx_desc_num += 1;
+ dma->rx_desc_num += 1;
+
+ dma->tx_virt = dma_alloc_coherent(dev, PAGE_SIZE * dma->tx_desc_num,
+ &dma->tx_addr, GFP_KERNEL);
+ if (!dma->tx_virt) {
+ dev_err(dev, "cannot allocate DMA TX buffer\n");
+ return ERR_PTR(-ENOMEM);
+ }
+
+ dma->rx_virt = dma_alloc_coherent(dev, PAGE_SIZE * dma->rx_desc_num,
+ &dma->rx_addr, GFP_KERNEL);
+ if (!dma->rx_virt) {
+ dev_err(dev, "cannot allocate DMA RX buffer\n");
+ return ERR_PTR(-ENOMEM);
+ }
+ }
+
+ espi_oob->mdev.parent = dev;
+ espi_oob->mdev.minor = MISC_DYNAMIC_MINOR;
+ espi_oob->mdev.name = devm_kasprintf(dev, GFP_KERNEL, "%s", OOB_MDEV_NAME);
+ espi_oob->mdev.fops = &aspeed_espi_oob_fops;
+ rc = misc_register(&espi_oob->mdev);
+ if (rc) {
+ dev_err(dev, "cannot register device\n");
+ return ERR_PTR(rc);
+ }
+
+ aspeed_espi_oob_enable(espi_oob);
+
+ return espi_oob;
+}
+
+void aspeed_espi_oob_free(struct device *dev, struct aspeed_espi_oob *espi_oob)
+{
+ struct aspeed_espi_oob_dma *dma = &espi_oob->dma;
+
+ if (espi_oob->dma_mode) {
+ dma_free_coherent(dev, sizeof(*dma->tx_desc) * dma->tx_desc_num,
+ dma->tx_desc, dma->tx_desc_addr);
+ dma_free_coherent(dev, sizeof(*dma->rx_desc) * dma->rx_desc_num,
+ dma->rx_desc, dma->rx_desc_addr);
+ dma_free_coherent(dev, PAGE_SIZE * dma->tx_desc_num,
+ dma->tx_virt, dma->tx_addr);
+ dma_free_coherent(dev, PAGE_SIZE * dma->rx_desc_num,
+ dma->rx_virt, dma->rx_addr);
+ }
+
+ mutex_destroy(&espi_oob->put_tx_mtx);
+ mutex_destroy(&espi_oob->get_rx_mtx);
+
+ misc_deregister(&espi_oob->mdev);
+}
diff --git a/drivers/soc/aspeed/aspeed-espi-oob.h b/drivers/soc/aspeed/aspeed-espi-oob.h
new file mode 100644
index 000000000000..03d74ef39e8b
--- /dev/null
+++ b/drivers/soc/aspeed/aspeed-espi-oob.h
@@ -0,0 +1,70 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Copyright 2021 Aspeed Technology Inc.
+ */
+#ifndef _ASPEED_ESPI_OOB_H_
+#define _ASPEED_ESPI_OOB_H_
+
+struct oob_tx_dma_desc {
+ uint32_t data_addr;
+ uint8_t cyc;
+ uint16_t tag : 4;
+ uint16_t len : 12;
+ uint8_t msg_type : 3;
+ uint8_t raz0 : 1;
+ uint8_t pec : 1;
+ uint8_t int_en : 1;
+ uint8_t pause : 1;
+ uint8_t raz1 : 1;
+ uint32_t raz2;
+ uint32_t raz3;
+} __packed;
+
+struct oob_rx_dma_desc {
+ uint32_t data_addr;
+ uint8_t cyc;
+ uint16_t tag : 4;
+ uint16_t len : 12;
+ uint8_t raz : 7;
+ uint8_t dirty : 1;
+} __packed;
+
+struct aspeed_espi_oob_dma {
+ uint32_t tx_desc_num;
+ uint32_t rx_desc_num;
+
+ struct oob_tx_dma_desc *tx_desc;
+ dma_addr_t tx_desc_addr;
+
+ struct oob_rx_dma_desc *rx_desc;
+ dma_addr_t rx_desc_addr;
+
+ void *tx_virt;
+ dma_addr_t tx_addr;
+
+ void *rx_virt;
+ dma_addr_t rx_addr;
+};
+
+struct aspeed_espi_oob {
+ uint32_t dma_mode;
+ struct aspeed_espi_oob_dma dma;
+
+ uint32_t rx_ready;
+ wait_queue_head_t wq;
+
+ struct mutex get_rx_mtx;
+ struct mutex put_tx_mtx;
+
+ spinlock_t lock;
+
+ struct miscdevice mdev;
+ struct aspeed_espi_ctrl *ctrl;
+};
+
+void aspeed_espi_oob_event(uint32_t sts, struct aspeed_espi_oob *espi_oob);
+void aspeed_espi_oob_enable(struct aspeed_espi_oob *espi_oob);
+void *aspeed_espi_oob_alloc(struct device *dev, struct aspeed_espi_ctrl *espi_ctrl);
+void aspeed_espi_oob_free(struct device *dev, struct aspeed_espi_oob *espi_oob);
+
+#endif
diff --git a/drivers/soc/aspeed/aspeed-espi-perif.c b/drivers/soc/aspeed/aspeed-espi-perif.c
new file mode 100644
index 000000000000..ebf3d9978b4a
--- /dev/null
+++ b/drivers/soc/aspeed/aspeed-espi-perif.c
@@ -0,0 +1,511 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright 2021 ASPEED Technology Inc.
+ */
+#include <linux/fs.h>
+#include <linux/of_device.h>
+#include <linux/miscdevice.h>
+#include <linux/mfd/syscon.h>
+#include <linux/regmap.h>
+#include <linux/uaccess.h>
+#include <linux/vmalloc.h>
+#include <linux/miscdevice.h>
+#include <linux/dma-mapping.h>
+
+#include "aspeed-espi-ioc.h"
+#include "aspeed-espi-ctrl.h"
+#include "aspeed-espi-perif.h"
+
+#define PERIF_MDEV_NAME "aspeed-espi-peripheral"
+#define PERIF_MEMCYC_UNLOCK_KEY 0xfedc756e
+#define PERIF_MEMCYC_SIZE_MIN 0x10000
+
+static long aspeed_espi_perif_pc_get_rx(struct file *fp,
+ struct aspeed_espi_ioc *ioc,
+ struct aspeed_espi_perif *espi_perif)
+{
+ int i, rc = 0;
+ uint32_t reg;
+ uint32_t cyc, tag, len;
+ uint8_t *pkt;
+ uint32_t pkt_len;
+ struct espi_comm_hdr *hdr;
+ unsigned long flags;
+ struct aspeed_espi_ctrl *espi_ctrl = espi_perif->ctrl;
+
+ if (fp->f_flags & O_NONBLOCK) {
+ if (mutex_trylock(&espi_perif->pc_rx_mtx))
+ return -EBUSY;
+
+ if (!espi_perif->rx_ready) {
+ rc = -ENODATA;
+ goto unlock_mtx_n_out;
+ }
+ } else {
+ mutex_lock(&espi_perif->pc_rx_mtx);
+
+ if (!espi_perif->rx_ready) {
+ rc = wait_event_interruptible(espi_perif->wq,
+ espi_perif->rx_ready);
+ if (rc == -ERESTARTSYS) {
+ rc = -EINTR;
+ goto unlock_mtx_n_out;
+ }
+ }
+ }
+
+ /* common header (i.e. cycle type, tag, and length) is taken by HW */
+ regmap_read(espi_ctrl->map, ESPI_PERIF_PC_RX_CTRL, &reg);
+ cyc = (reg & ESPI_PERIF_PC_RX_CTRL_CYC_MASK) >> ESPI_PERIF_PC_RX_CTRL_CYC_SHIFT;
+ tag = (reg & ESPI_PERIF_PC_RX_CTRL_TAG_MASK) >> ESPI_PERIF_PC_RX_CTRL_TAG_SHIFT;
+ len = (reg & ESPI_PERIF_PC_RX_CTRL_LEN_MASK) >> ESPI_PERIF_PC_RX_CTRL_LEN_SHIFT;
+
+ /*
+ * calculate the length of the rest part of the
+ * eSPI packet to be read from HW and copied to
+ * user space.
+ */
+ switch (cyc) {
+ case ESPI_PERIF_MSG:
+ pkt_len = len + sizeof(struct espi_perif_msg);
+ break;
+ case ESPI_PERIF_MSG_D:
+ pkt_len = ((len) ? len : ESPI_PLD_LEN_MAX) +
+ sizeof(struct espi_perif_msg);
+ break;
+ case ESPI_PERIF_SUC_CMPLT_D_MIDDLE:
+ case ESPI_PERIF_SUC_CMPLT_D_FIRST:
+ case ESPI_PERIF_SUC_CMPLT_D_LAST:
+ case ESPI_PERIF_SUC_CMPLT_D_ONLY:
+ pkt_len = ((len) ? len : ESPI_PLD_LEN_MAX) +
+ sizeof(struct espi_perif_cmplt);
+ break;
+ case ESPI_PERIF_SUC_CMPLT:
+ case ESPI_PERIF_UNSUC_CMPLT:
+ pkt_len = len + sizeof(struct espi_perif_cmplt);
+ break;
+ default:
+ rc = -EFAULT;
+ goto unlock_mtx_n_out;
+ }
+
+ if (ioc->pkt_len < pkt_len) {
+ rc = -EINVAL;
+ goto unlock_mtx_n_out;
+ }
+
+ pkt = vmalloc(pkt_len);
+ if (!pkt) {
+ rc = -ENOMEM;
+ goto unlock_mtx_n_out;
+ }
+
+ hdr = (struct espi_comm_hdr *)pkt;
+ hdr->cyc = cyc;
+ hdr->tag = tag;
+ hdr->len_h = len >> 8;
+ hdr->len_l = len & 0xff;
+
+ if (espi_perif->dma_mode) {
+ memcpy(hdr + 1, espi_perif->dma.pc_rx_virt,
+ pkt_len - sizeof(*hdr));
+ } else {
+ for (i = sizeof(*hdr); i < pkt_len; ++i) {
+ regmap_read(espi_ctrl->map,
+ ESPI_PERIF_PC_RX_PORT, &reg);
+ pkt[i] = reg & 0xff;
+ }
+ }
+
+ if (copy_to_user((void __user *)ioc->pkt, pkt, pkt_len)) {
+ rc = -EFAULT;
+ goto free_n_out;
+ }
+
+ spin_lock_irqsave(&espi_perif->lock, flags);
+
+ regmap_write_bits(espi_ctrl->map, ESPI_PERIF_PC_RX_CTRL,
+ ESPI_PERIF_PC_RX_CTRL_PEND_SERV,
+ ESPI_PERIF_PC_RX_CTRL_PEND_SERV);
+
+ espi_perif->rx_ready = 0;
+
+ spin_unlock_irqrestore(&espi_perif->lock, flags);
+
+free_n_out:
+ vfree(pkt);
+
+unlock_mtx_n_out:
+ mutex_unlock(&espi_perif->pc_rx_mtx);
+
+ return rc;
+}
+
+static long aspeed_espi_perif_pc_put_tx(struct file *fp,
+ struct aspeed_espi_ioc *ioc,
+ struct aspeed_espi_perif *espi_perif)
+{
+ int i, rc = 0;
+ uint32_t reg;
+ uint32_t cyc, tag, len;
+ uint8_t *pkt;
+ struct espi_comm_hdr *hdr;
+ struct aspeed_espi_ctrl *espi_ctrl = espi_perif->ctrl;
+
+ if (!mutex_trylock(&espi_perif->pc_tx_mtx))
+ return -EAGAIN;
+
+ regmap_read(espi_ctrl->map, ESPI_PERIF_PC_TX_CTRL, &reg);
+ if (reg & ESPI_PERIF_PC_TX_CTRL_TRIGGER) {
+ rc = -EBUSY;
+ goto unlock_n_out;
+ }
+
+ pkt = vmalloc(ioc->pkt_len);
+ if (!pkt) {
+ rc = -ENOMEM;
+ goto unlock_n_out;
+ }
+
+ hdr = (struct espi_comm_hdr *)pkt;
+
+ if (copy_from_user(pkt, (void __user *)ioc->pkt, ioc->pkt_len)) {
+ rc = -EFAULT;
+ goto free_n_out;
+ }
+
+ /*
+ * common header (i.e. cycle type, tag, and length)
+ * part is written to HW registers
+ */
+ if (espi_perif->dma_mode) {
+ memcpy(espi_perif->dma.pc_tx_virt, hdr + 1,
+ ioc->pkt_len - sizeof(*hdr));
+ dma_wmb();
+ } else {
+ for (i = sizeof(*hdr); i < ioc->pkt_len; ++i)
+ regmap_write(espi_ctrl->map,
+ ESPI_PERIF_PC_TX_PORT, pkt[i]);
+ }
+
+ cyc = hdr->cyc;
+ tag = hdr->tag;
+ len = (hdr->len_h << 8) | (hdr->len_l & 0xff);
+
+ reg = ((cyc << ESPI_PERIF_PC_TX_CTRL_CYC_SHIFT) & ESPI_PERIF_PC_TX_CTRL_CYC_MASK)
+ | ((tag << ESPI_PERIF_PC_TX_CTRL_TAG_SHIFT) & ESPI_PERIF_PC_TX_CTRL_TAG_MASK)
+ | ((len << ESPI_PERIF_PC_TX_CTRL_LEN_SHIFT) & ESPI_PERIF_PC_TX_CTRL_LEN_MASK)
+ | ESPI_PERIF_PC_TX_CTRL_TRIGGER;
+
+ regmap_write(espi_ctrl->map, ESPI_PERIF_PC_TX_CTRL, reg);
+
+free_n_out:
+ vfree(pkt);
+
+unlock_n_out:
+ mutex_unlock(&espi_perif->pc_tx_mtx);
+
+ return rc;
+}
+
+static long aspeed_espi_perif_np_put_tx(struct file *fp,
+ struct aspeed_espi_ioc *ioc,
+ struct aspeed_espi_perif *espi_perif)
+{
+ int i, rc = 0;
+ uint32_t reg;
+ uint32_t cyc, tag, len;
+ uint8_t *pkt;
+ struct espi_comm_hdr *hdr;
+ struct aspeed_espi_ctrl *espi_ctrl = espi_perif->ctrl;
+
+ if (!mutex_trylock(&espi_perif->np_tx_mtx))
+ return -EAGAIN;
+
+ regmap_read(espi_ctrl->map, ESPI_PERIF_NP_TX_CTRL, &reg);
+ if (reg & ESPI_PERIF_NP_TX_CTRL_TRIGGER) {
+ rc = -EBUSY;
+ goto unlock_n_out;
+ }
+
+ pkt = vmalloc(ioc->pkt_len);
+ if (!pkt) {
+ rc = -ENOMEM;
+ goto unlock_n_out;
+ }
+
+ hdr = (struct espi_comm_hdr *)pkt;
+
+ if (copy_from_user(pkt, (void __user *)ioc->pkt, ioc->pkt_len)) {
+ rc = -EFAULT;
+ goto free_n_out;
+ }
+
+ /*
+ * common header (i.e. cycle type, tag, and length)
+ * part is written to HW registers
+ */
+ if (espi_perif->dma_mode) {
+ memcpy(espi_perif->dma.np_tx_virt, hdr + 1,
+ ioc->pkt_len - sizeof(*hdr));
+ dma_wmb();
+ } else {
+ for (i = sizeof(*hdr); i < ioc->pkt_len; ++i)
+ regmap_write(espi_ctrl->map,
+ ESPI_PERIF_NP_TX_PORT, pkt[i]);
+ }
+
+ cyc = hdr->cyc;
+ tag = hdr->tag;
+ len = (hdr->len_h << 8) | (hdr->len_l & 0xff);
+
+ reg = ((cyc << ESPI_PERIF_NP_TX_CTRL_CYC_SHIFT) & ESPI_PERIF_NP_TX_CTRL_CYC_MASK)
+ | ((tag << ESPI_PERIF_NP_TX_CTRL_TAG_SHIFT) & ESPI_PERIF_NP_TX_CTRL_TAG_MASK)
+ | ((len << ESPI_PERIF_NP_TX_CTRL_LEN_SHIFT) & ESPI_PERIF_NP_TX_CTRL_LEN_MASK)
+ | ESPI_PERIF_NP_TX_CTRL_TRIGGER;
+
+ regmap_write(espi_ctrl->map, ESPI_PERIF_NP_TX_CTRL, reg);
+
+free_n_out:
+ vfree(pkt);
+
+unlock_n_out:
+ mutex_unlock(&espi_perif->np_tx_mtx);
+
+ return rc;
+
+}
+
+static long aspeed_espi_perif_ioctl(struct file *fp, unsigned int cmd, unsigned long arg)
+{
+ struct aspeed_espi_ioc ioc;
+ struct aspeed_espi_perif *espi_perif = container_of(
+ fp->private_data,
+ struct aspeed_espi_perif,
+ mdev);
+
+ if (copy_from_user(&ioc, (void __user *)arg, sizeof(ioc)))
+ return -EFAULT;
+
+ if (ioc.pkt_len > ESPI_PKT_LEN_MAX)
+ return -EINVAL;
+
+ switch (cmd) {
+ case ASPEED_ESPI_PERIF_PC_GET_RX:
+ return aspeed_espi_perif_pc_get_rx(fp, &ioc, espi_perif);
+ case ASPEED_ESPI_PERIF_PC_PUT_TX:
+ return aspeed_espi_perif_pc_put_tx(fp, &ioc, espi_perif);
+ case ASPEED_ESPI_PERIF_NP_PUT_TX:
+ return aspeed_espi_perif_np_put_tx(fp, &ioc, espi_perif);
+ };
+
+ return -EINVAL;
+}
+
+static int aspeed_espi_perif_mmap(struct file *fp, struct vm_area_struct *vma)
+{
+ struct aspeed_espi_perif *espi_perif = container_of(
+ fp->private_data,
+ struct aspeed_espi_perif,
+ mdev);
+ unsigned long vm_size = vma->vm_end - vma->vm_start;
+ pgprot_t prot = vma->vm_page_prot;
+
+ if (!espi_perif->mcyc_enable)
+ return -EPERM;
+
+ if (((vma->vm_pgoff << PAGE_SHIFT) + vm_size) > espi_perif->mcyc_size)
+ return -EINVAL;
+
+ prot = pgprot_noncached(prot);
+
+ if (remap_pfn_range(vma, vma->vm_start,
+ (espi_perif->mcyc_taddr >> PAGE_SHIFT) + vma->vm_pgoff,
+ vm_size, prot))
+ return -EAGAIN;
+
+ return 0;
+}
+
+void aspeed_espi_perif_event(uint32_t sts, struct aspeed_espi_perif *espi_perif)
+{
+ unsigned long flags;
+
+ if (sts & ESPI_INT_STS_PERIF_PC_RX_CMPLT) {
+ spin_lock_irqsave(&espi_perif->lock, flags);
+ espi_perif->rx_ready = 1;
+ spin_unlock_irqrestore(&espi_perif->lock, flags);
+
+ wake_up_interruptible(&espi_perif->wq);
+ }
+}
+
+void aspeed_espi_perif_enable(struct aspeed_espi_perif *espi_perif)
+{
+ struct aspeed_espi_perif_dma *dma = &espi_perif->dma;
+ struct aspeed_espi_ctrl *espi_ctrl = espi_perif->ctrl;
+
+ if (espi_perif->mcyc_enable) {
+ if (espi_ctrl->model->version == ESPI_AST2500) {
+ regmap_write(espi_ctrl->map, ESPI_PERIF_PC_RX_MASK,
+ PERIF_MEMCYC_UNLOCK_KEY);
+ regmap_write(espi_ctrl->map, ESPI_PERIF_PC_RX_MASK,
+ espi_perif->mcyc_mask);
+ } else {
+ regmap_write(espi_ctrl->map, ESPI_PERIF_PC_RX_MASK,
+ espi_perif->mcyc_mask | ESPI_PERIF_PC_RX_MASK_CFG_WP);
+ regmap_update_bits(espi_ctrl->map, ESPI_CTRL2,
+ ESPI_CTRL2_MEMCYC_RD_DIS | ESPI_CTRL2_MEMCYC_WR_DIS, 0);
+ }
+
+ regmap_write(espi_ctrl->map, ESPI_PERIF_PC_RX_SADDR, espi_perif->mcyc_saddr);
+ regmap_write(espi_ctrl->map, ESPI_PERIF_PC_RX_TADDR, espi_perif->mcyc_taddr);
+ }
+
+ if (espi_perif->dma_mode) {
+ regmap_write(espi_ctrl->map, ESPI_PERIF_PC_RX_DMA, dma->pc_rx_addr);
+ regmap_write(espi_ctrl->map, ESPI_PERIF_PC_TX_DMA, dma->pc_tx_addr);
+ regmap_write(espi_ctrl->map, ESPI_PERIF_NP_TX_DMA, dma->np_tx_addr);
+
+ regmap_update_bits(espi_ctrl->map, ESPI_CTRL,
+ ESPI_CTRL_PERIF_NP_TX_DMA_EN |
+ ESPI_CTRL_PERIF_PC_TX_DMA_EN |
+ ESPI_CTRL_PERIF_PC_RX_DMA_EN,
+ ESPI_CTRL_PERIF_NP_TX_DMA_EN |
+ ESPI_CTRL_PERIF_PC_TX_DMA_EN |
+ ESPI_CTRL_PERIF_PC_RX_DMA_EN);
+ }
+
+ regmap_write(espi_ctrl->map, ESPI_INT_STS,
+ ESPI_INT_STS_PERIF_BITS);
+
+ regmap_update_bits(espi_ctrl->map, ESPI_INT_EN,
+ ESPI_INT_EN_PERIF_BITS,
+ ESPI_INT_EN_PERIF_BITS);
+
+ regmap_update_bits(espi_ctrl->map, ESPI_CTRL,
+ ESPI_CTRL_PERIF_SW_RDY,
+ ESPI_CTRL_PERIF_SW_RDY);
+}
+
+static const struct file_operations aspeed_espi_perif_fops = {
+ .owner = THIS_MODULE,
+ .mmap = aspeed_espi_perif_mmap,
+ .unlocked_ioctl = aspeed_espi_perif_ioctl,
+};
+
+void *aspeed_espi_perif_alloc(struct device *dev, struct aspeed_espi_ctrl *espi_ctrl)
+{
+ int rc;
+ struct aspeed_espi_perif *espi_perif;
+ struct aspeed_espi_perif_dma *dma;
+
+ espi_perif = devm_kzalloc(dev, sizeof(*espi_perif), GFP_KERNEL);
+ if (!espi_perif)
+ return ERR_PTR(-ENOMEM);
+
+ espi_perif->ctrl = espi_ctrl;
+
+ init_waitqueue_head(&espi_perif->wq);
+
+ spin_lock_init(&espi_perif->lock);
+
+ mutex_init(&espi_perif->pc_rx_mtx);
+ mutex_init(&espi_perif->pc_tx_mtx);
+ mutex_init(&espi_perif->np_tx_mtx);
+
+ espi_perif->mcyc_enable = of_property_read_bool(dev->of_node, "perif,memcyc-enable");
+ if (espi_perif->mcyc_enable) {
+ rc = of_property_read_u32(dev->of_node, "perif,memcyc-src-addr",
+ &espi_perif->mcyc_saddr);
+ if (rc) {
+ dev_err(dev, "cannot get Host source address for memory cycle\n");
+ return ERR_PTR(-ENODEV);
+ }
+
+ rc = of_property_read_u32(dev->of_node, "perif,memcyc-size",
+ &espi_perif->mcyc_size);
+ if (rc) {
+ dev_err(dev, "cannot get size for memory cycle\n");
+ return ERR_PTR(-ENODEV);
+ }
+
+ if (espi_perif->mcyc_size < PERIF_MEMCYC_SIZE_MIN)
+ espi_perif->mcyc_size = PERIF_MEMCYC_SIZE_MIN;
+ else
+ espi_perif->mcyc_size = roundup_pow_of_two(espi_perif->mcyc_size);
+
+ espi_perif->mcyc_mask = ~(espi_perif->mcyc_size - 1);
+ espi_perif->mcyc_virt = dma_alloc_coherent(dev, espi_perif->mcyc_size,
+ &espi_perif->mcyc_taddr, GFP_KERNEL);

Here and a few lines below, dma_alloc_coherent() could be replaced by dmam_alloc_coherent() (its managed version) to simplify error handling and freeing of resources.


+ if (!espi_perif->mcyc_virt) {
+ dev_err(dev, "cannot allocate memory cycle region\n");
+ return ERR_PTR(-ENOMEM);
+ }
+ }
+
+ if (of_property_read_bool(dev->of_node, "perif,dma-mode")) {
+ dma = &espi_perif->dma;
+
+ dma->pc_tx_virt = dma_alloc_coherent(dev, PAGE_SIZE,
+ &dma->pc_tx_addr, GFP_KERNEL);
+ if (!dma->pc_tx_virt) {
+ dev_err(dev, "cannot allocate posted TX DMA buffer\n");
+ return ERR_PTR(-ENOMEM);
+ }
+
+ dma->pc_rx_virt = dma_alloc_coherent(dev, PAGE_SIZE,
+ &dma->pc_rx_addr, GFP_KERNEL);
+ if (!dma->pc_rx_virt) {
+ dev_err(dev, "cannot allocate posted RX DMA buffer\n");
+ return ERR_PTR(-ENOMEM);
+ }
+
+ dma->np_tx_virt = dma_alloc_coherent(dev, PAGE_SIZE,
+ &dma->np_tx_addr, GFP_KERNEL);
+ if (!dma->np_tx_virt) {
+ dev_err(dev, "cannot allocate non-posted TX DMA buffer\n");
+ return ERR_PTR(-ENOMEM);
+ }
+
+ espi_perif->dma_mode = 1;
+ }
+
+ espi_perif->mdev.parent = dev;
+ espi_perif->mdev.minor = MISC_DYNAMIC_MINOR;
+ espi_perif->mdev.name = devm_kasprintf(dev, GFP_KERNEL, "%s", PERIF_MDEV_NAME);
+ espi_perif->mdev.fops = &aspeed_espi_perif_fops;
+ rc = misc_register(&espi_perif->mdev);
+ if (rc) {
+ dev_err(dev, "cannot register device\n");
+ return ERR_PTR(rc);
+ }
+
+ aspeed_espi_perif_enable(espi_perif);
+
+ return espi_perif;
+}
+
+void aspeed_espi_perif_free(struct device *dev, struct aspeed_espi_perif *espi_perif)
+{
+ struct aspeed_espi_perif_dma *dma = &espi_perif->dma;
+
+ if (espi_perif->mcyc_virt)
+ dma_free_coherent(dev, espi_perif->mcyc_size,
+ espi_perif->mcyc_virt,
+ espi_perif->mcyc_taddr);
+
+ if (espi_perif->dma_mode) {
+ dma_free_coherent(dev, PAGE_SIZE, dma->pc_tx_virt,
+ dma->pc_tx_addr);
+ dma_free_coherent(dev, PAGE_SIZE, dma->pc_rx_virt,
+ dma->pc_rx_addr);
+ dma_free_coherent(dev, PAGE_SIZE, dma->np_tx_virt,
+ dma->np_tx_addr);
+ }
+
+ mutex_destroy(&espi_perif->pc_tx_mtx);
+ mutex_destroy(&espi_perif->np_tx_mtx);
+
+ misc_deregister(&espi_perif->mdev);
+}
diff --git a/drivers/soc/aspeed/aspeed-espi-perif.h b/drivers/soc/aspeed/aspeed-espi-perif.h
new file mode 100644
index 000000000000..1b964e4680f5
--- /dev/null
+++ b/drivers/soc/aspeed/aspeed-espi-perif.h
@@ -0,0 +1,45 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Copyright 2021 ASPEED Technology Inc.
+ */
+#ifndef _ASPEED_ESPI_PERIF_H_
+#define _ASPEED_ESPI_PERIF_H_
+
+struct aspeed_espi_perif_dma {
+ void *pc_tx_virt;
+ dma_addr_t pc_tx_addr;
+ void *pc_rx_virt;
+ dma_addr_t pc_rx_addr;
+ void *np_tx_virt;
+ dma_addr_t np_tx_addr;
+};
+
+struct aspeed_espi_perif {
+ uint32_t mcyc_enable;
+ void *mcyc_virt;
+ uint32_t mcyc_saddr;
+ phys_addr_t mcyc_taddr;
+ uint32_t mcyc_size;
+ uint32_t mcyc_mask;
+
+ uint32_t dma_mode;
+ struct aspeed_espi_perif_dma dma;
+
+ uint32_t rx_ready;
+ wait_queue_head_t wq;
+
+ spinlock_t lock;
+ struct mutex pc_rx_mtx;
+ struct mutex pc_tx_mtx;
+ struct mutex np_tx_mtx;
+
+ struct miscdevice mdev;
+ struct aspeed_espi_ctrl *ctrl;
+};
+
+void aspeed_espi_perif_event(uint32_t sts, struct aspeed_espi_perif *espi_perif);
+void aspeed_espi_perif_enable(struct aspeed_espi_perif *espi_perif);
+void *aspeed_espi_perif_alloc(struct device *dev, struct aspeed_espi_ctrl *espi_ctrl);
+void aspeed_espi_perif_free(struct device *dev, struct aspeed_espi_perif *espi_perif);
+
+#endif
diff --git a/drivers/soc/aspeed/aspeed-espi-vw.c b/drivers/soc/aspeed/aspeed-espi-vw.c
new file mode 100644
index 000000000000..2bdfedfea12e
--- /dev/null
+++ b/drivers/soc/aspeed/aspeed-espi-vw.c
@@ -0,0 +1,142 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright 2021 ASPEED Technology Inc.
+ */
+#include <linux/fs.h>
+#include <linux/of_device.h>
+#include <linux/miscdevice.h>
+#include <linux/mfd/syscon.h>
+#include <linux/regmap.h>
+#include <linux/uaccess.h>
+#include <linux/vmalloc.h>
+#include <linux/miscdevice.h>
+#include <linux/dma-mapping.h>
+
+#include "aspeed-espi-ioc.h"
+#include "aspeed-espi-ctrl.h"
+#include "aspeed-espi-vw.h"
+
+#define VW_MDEV_NAME "aspeed-espi-vw"
+
+static long aspeed_espi_vw_ioctl(struct file *fp, unsigned int cmd, unsigned long arg)
+{
+ uint32_t val;
+
+ struct aspeed_espi_vw *espi_vw = container_of(fp->private_data,
+ struct aspeed_espi_vw,
+ mdev);
+ struct aspeed_espi_ctrl *espi_ctrl = espi_vw->ctrl;
+
+ switch (cmd) {
+ case ASPEED_ESPI_VW_GET_GPIO_VAL:
+ regmap_read(espi_ctrl->map, ESPI_VW_GPIO_VAL, &val);
+ if (put_user(val, (uint32_t __user *)arg))
+ return -EFAULT;
+ break;
+
+ case ASPEED_ESPI_VW_PUT_GPIO_VAL:
+ if (get_user(val, (uint32_t __user *)arg))
+ return -EFAULT;
+ regmap_write(espi_ctrl->map, ESPI_VW_GPIO_VAL, val);
+ break;
+
+ default:
+ return -EINVAL;
+ };
+
+ return 0;
+}
+
+void aspeed_espi_vw_event(uint32_t sts, struct aspeed_espi_vw *espi_vw)
+{
+ uint32_t sysevt_sts;
+ struct aspeed_espi_ctrl *espi_ctrl = espi_vw->ctrl;
+
+ regmap_read(espi_ctrl->map, ESPI_INT_STS, &sts);
+
+ if (sts & ESPI_INT_STS_VW_SYSEVT) {
+ regmap_read(espi_ctrl->map, ESPI_SYSEVT_INT_STS, &sysevt_sts);
+
+ if (espi_ctrl->model->version == ESPI_AST2500) {
+ if (sysevt_sts & ESPI_SYSEVT_INT_STS_HOST_RST_WARN)
+ regmap_update_bits(espi_ctrl->map, ESPI_SYSEVT,
+ ESPI_SYSEVT_HOST_RST_ACK,
+ ESPI_SYSEVT_HOST_RST_ACK);
+
+ if (sysevt_sts & ESPI_SYSEVT_INT_STS_OOB_RST_WARN)
+ regmap_update_bits(espi_ctrl->map, ESPI_SYSEVT,
+ ESPI_SYSEVT_OOB_RST_ACK,
+ ESPI_SYSEVT_OOB_RST_ACK);
+ }
+
+ regmap_write(espi_ctrl->map, ESPI_SYSEVT_INT_STS, sysevt_sts);
+ }
+
+ if (sts & ESPI_INT_STS_VW_SYSEVT1) {
+ regmap_read(espi_ctrl->map, ESPI_SYSEVT1_INT_STS, &sysevt_sts);
+
+ if (sysevt_sts & ESPI_SYSEVT1_INT_STS_SUSPEND_WARN)
+ regmap_update_bits(espi_ctrl->map, ESPI_SYSEVT1,
+ ESPI_SYSEVT1_SUSPEND_ACK,
+ ESPI_SYSEVT1_SUSPEND_ACK);
+
+ regmap_write(espi_ctrl->map, ESPI_SYSEVT1_INT_STS, sysevt_sts);
+ }
+}
+
+void aspeed_espi_vw_enable(struct aspeed_espi_vw *espi_vw)
+{
+ struct aspeed_espi_ctrl *espi_ctrl = espi_vw->ctrl;
+
+ regmap_write(espi_ctrl->map, ESPI_INT_STS,
+ ESPI_INT_STS_VW_BITS);
+
+ regmap_update_bits(espi_ctrl->map, ESPI_INT_EN,
+ ESPI_INT_EN_VW_BITS,
+ ESPI_INT_EN_VW_BITS);
+
+ /*
+ * Enforce VW GPIO to SW mode due to security concern.
+ * The HW mode allows the Host to manipulate BMC GPIOs
+ * without notififications.
+ */
+ regmap_update_bits(espi_ctrl->map, ESPI_CTRL,
+ ESPI_CTRL_VW_GPIO_SW_MODE | ESPI_CTRL_VW_SW_RDY,
+ ESPI_CTRL_VW_GPIO_SW_MODE | ESPI_CTRL_VW_SW_RDY);
+}
+
+static const struct file_operations aspeed_espi_vw_fops = {
+ .owner = THIS_MODULE,
+ .unlocked_ioctl = aspeed_espi_vw_ioctl,
+};
+
+void *aspeed_espi_vw_alloc(struct device *dev, struct aspeed_espi_ctrl *espi_ctrl)
+{
+ int rc;
+ struct aspeed_espi_vw *espi_vw;
+
+ espi_vw = devm_kzalloc(dev, sizeof(*espi_vw), GFP_KERNEL);
+ if (!espi_vw)
+ return ERR_PTR(-ENOMEM);
+
+ espi_vw->ctrl = espi_ctrl;
+
+ espi_vw->mdev.parent = dev;
+ espi_vw->mdev.minor = MISC_DYNAMIC_MINOR;
+ espi_vw->mdev.name = devm_kasprintf(dev, GFP_KERNEL, "%s", VW_MDEV_NAME);
+ espi_vw->mdev.fops = &aspeed_espi_vw_fops;
+ rc = misc_register(&espi_vw->mdev);
+ if (rc) {
+ dev_err(dev, "cannot register device\n");
+ return ERR_PTR(rc);
+ }
+
+ aspeed_espi_vw_enable(espi_vw);
+
+ return espi_vw;
+}
+
+void aspeed_espi_vw_free(struct device *dev, struct aspeed_espi_vw *espi_vw)
+{
+ misc_deregister(&espi_vw->mdev);
+}
diff --git a/drivers/soc/aspeed/aspeed-espi-vw.h b/drivers/soc/aspeed/aspeed-espi-vw.h
new file mode 100644
index 000000000000..aba9c414ac1b
--- /dev/null
+++ b/drivers/soc/aspeed/aspeed-espi-vw.h
@@ -0,0 +1,21 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Copyright 2021 ASPEED Technology Inc.
+ */
+#ifndef _ASPEED_ESPI_VW_H_
+#define _ASPEED_ESPI_VW_H_
+
+struct aspeed_espi_vw {
+ int irq;
+ int irq_reset;
+
+ struct miscdevice mdev;
+ struct aspeed_espi_ctrl *ctrl;
+};
+
+void aspeed_espi_vw_event(uint32_t sts, struct aspeed_espi_vw *espi_vw);
+void aspeed_espi_vw_enable(struct aspeed_espi_vw *espi_vw);
+void *aspeed_espi_vw_alloc(struct device *dev, struct aspeed_espi_ctrl *espi_ctrl);
+void aspeed_espi_vw_free(struct device *dev, struct aspeed_espi_vw *espi_vw);
+
+#endif