Re: [PATCH v6 3/3] mailbox: mediatek: add support for adsp mailbox controller

From: AngeloGioacchino Del Regno
Date: Fri Nov 26 2021 - 06:33:55 EST

Il 26/11/21 10:30, allen-kh.cheng ha scritto:
From: Allen-KH Cheng <Allen-KH.Cheng@xxxxxxxxxxxx>

This patch is to for MediaTek ADSP IPC mailbox controller driver
It is used to send short messages between processors with adsp

Signed-off-by: Allen-KH Cheng <Allen-KH.Cheng@xxxxxxxxxxxx>
Reviewed-by: Tzung-Bi Shih <tzungbi@xxxxxxxxxx>
---
drivers/mailbox/Kconfig | 7 ++
drivers/mailbox/Makefile | 2 +
drivers/mailbox/mtk-adsp-mailbox.c | 178 +++++++++++++++++++++++++++++
3 files changed, 187 insertions(+)
create mode 100644 drivers/mailbox/mtk-adsp-mailbox.c


Hello! Thanks for the patch!
However, there's something to improve...

diff --git a/drivers/mailbox/Kconfig b/drivers/mailbox/Kconfig
index c9fc06c7e685..c44a0102585d 100644
--- a/drivers/mailbox/Kconfig
+++ b/drivers/mailbox/Kconfig
@@ -226,6 +226,13 @@ config STM32_IPCC
with hardware for Inter-Processor Communication Controller (IPCC)
between processors. Say Y here if you want to have this support.
+config MTK_ADSP_IPC_MBOX
+ tristate "MediaTek ADSP Mailbox Controller"
+ depends on ARCH_MEDIATEK || COMPILE_TEST
+ help
+ Say yes here to add support for MediaTek ADSP IPC mailbox controller
+ driver. It is used to send short messages between processors with dsp.
+
config MTK_CMDQ_MBOX
tristate "MediaTek CMDQ Mailbox Support"
depends on ARCH_MEDIATEK || COMPILE_TEST
diff --git a/drivers/mailbox/Makefile b/drivers/mailbox/Makefile
index c2089f04887e..13d5c81852ca 100644
--- a/drivers/mailbox/Makefile
+++ b/drivers/mailbox/Makefile
@@ -49,6 +49,8 @@ obj-$(CONFIG_TEGRA_HSP_MBOX) += tegra-hsp.o
obj-$(CONFIG_STM32_IPCC) += stm32-ipcc.o
+obj-$(CONFIG_MTK_ADSP_IPC_MBOX) += mtk-adsp-mailbox.o
+
obj-$(CONFIG_MTK_CMDQ_MBOX) += mtk-cmdq-mailbox.o
obj-$(CONFIG_ZYNQMP_IPI_MBOX) += zynqmp-ipi-mailbox.o
diff --git a/drivers/mailbox/mtk-adsp-mailbox.c b/drivers/mailbox/mtk-adsp-mailbox.c
new file mode 100644
index 000000000000..8928bb3874c4
--- /dev/null
+++ b/drivers/mailbox/mtk-adsp-mailbox.c
@@ -0,0 +1,178 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2021 MediaTek Corporation. All rights reserved.
+ * Author: Allen-KH Cheng <allen-kh.cheng@xxxxxxxxxxxx>
+ */
+
+#include <linux/firmware/mediatek/mtk-adsp-ipc.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/iopoll.h>
+#include <linux/kernel.h>
+#include <linux/mailbox_controller.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/slab.h>
+
+/* adsp mbox register offset */
+#define MTK_ADSP_MBOX_IN_CMD 0x00
+#define MTK_ADSP_MBOX_IN_CMD_CLR 0x04
+#define MTK_ADSP_MBOX_OUT_CMD 0x1c
+#define MTK_ADSP_MBOX_OUT_CMD_CLR 0x20
+#define MTK_ADSP_MBOX_IN_MSG0 0x08
+#define MTK_ADSP_MBOX_IN_MSG1 0x0C
+#define MTK_ADSP_MBOX_OUT_MSG0 0x24
+#define MTK_ADSP_MBOX_OUT_MSG1 0x28
+
+struct mtk_adsp_mbox_priv {
+ struct device *dev;
+ struct mbox_controller mbox;
+ void __iomem *va_mboxreg;
+};
+
+static irqreturn_t mtk_adsp_ipc_irq_handler(int irq, void *data)
+{
+ struct mbox_chan *ch = data;
+ struct adsp_mbox_ch_info *ch_info = ch->con_priv;
+ void __iomem *reg = ch_info->va_reg;
+ u32 op = readl(reg + MTK_ADSP_MBOX_OUT_CMD);
+
+ writel(op, reg + MTK_ADSP_MBOX_OUT_CMD_CLR);
+
+ return IRQ_WAKE_THREAD;
+}
+
+static irqreturn_t mtk_adsp_ipc_handler(int irq, void *data)
+{
+ struct mbox_chan *ch = data;
+ struct adsp_mbox_ch_info *ch_info = ch->con_priv;
+
+ mbox_chan_received_data(ch, ch_info);
+
+ return IRQ_HANDLED;
+}
+
+static struct mbox_chan *mtk_adsp_mbox_xlate(struct mbox_controller *mbox,
+ const struct of_phandle_args *sp)
+{
+ return &mbox->chans[sp->args[0]];
+}
+
+static int mtk_adsp_mbox_startup(struct mbox_chan *chan)
+{
+ struct adsp_mbox_ch_info *ch_info = chan->con_priv;
+ void __iomem *reg = ch_info->va_reg;
+
+ /* Clear DSP mbox command */
+ writel(0xFFFFFFFF, reg + MTK_ADSP_MBOX_IN_CMD_CLR);
+ writel(0xFFFFFFFF, reg + MTK_ADSP_MBOX_OUT_CMD_CLR);
+
+ return 0;
+}
+
+static void mtk_adsp_mbox_shutdown(struct mbox_chan *chan)
+{
+ struct adsp_mbox_ch_info *ch_info = chan->con_priv;
+ void __iomem *reg = ch_info->va_reg;
+
+ /* Clear DSP mbox command */
+ writel(0xFFFFFFFF, reg + MTK_ADSP_MBOX_IN_CMD_CLR);
+ writel(0xFFFFFFFF, reg + MTK_ADSP_MBOX_OUT_CMD_CLR);
+ chan->con_priv = NULL;
+}
+
+static int mtk_adsp_mbox_send_data(struct mbox_chan *chan, void *data)
+{
+ struct adsp_mbox_ch_info *ch_info = chan->con_priv;
+ void __iomem *reg = ch_info->va_reg;
+
+ writel(ch_info->ipc_op_val, reg + MTK_ADSP_MBOX_IN_CMD);
+
+ return 0;
+}
+
+static bool mtk_adsp_mbox_last_tx_done(struct mbox_chan *chan)
+{
+ struct adsp_mbox_ch_info *ch_info = chan->con_priv;
+ void __iomem *reg = ch_info->va_reg;
+
+ return readl(reg + MTK_ADSP_MBOX_IN_CMD) == 0;
+}
+
+static const struct mbox_chan_ops adsp_mbox_chan_ops = {
+ .send_data = mtk_adsp_mbox_send_data,
+ .startup = mtk_adsp_mbox_startup,
+ .shutdown = mtk_adsp_mbox_shutdown,
+ .last_tx_done = mtk_adsp_mbox_last_tx_done,
+};
+
+static int mtk_adsp_mbox_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct mbox_controller *mbox;
+ struct mtk_adsp_mbox_priv *priv;
+ struct resource *res;

drivers/mailbox/mtk-adsp-mailbox.c: In function ‘mtk_adsp_mbox_probe’:

drivers/mailbox/mtk-adsp-mailbox.c:114:19: warning: unused variable ‘res’ [-Wunused-variable]

114 | struct resource *res;


Please remove this unused variable

+ struct adsp_mbox_ch_info *ch_info;
+ int ret;
+ int irq;

What about `int irq, ret;` ?

+
+ priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ mbox = &priv->mbox;
+ mbox->dev = dev;
+ mbox->ops = &adsp_mbox_chan_ops;
+ mbox->txdone_irq = false;
+ mbox->txdone_poll = true;
+ mbox->of_xlate = mtk_adsp_mbox_xlate;
+ mbox->num_chans = 1;
+ mbox->chans = devm_kzalloc(mbox->dev, sizeof(*mbox->chans), GFP_KERNEL);
+ if (!mbox->chans)
+ return -ENOMEM;
+
+ priv->va_mboxreg = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(priv->va_mboxreg))
+ return PTR_ERR(priv->va_mboxreg);
+
+ irq = platform_get_irq(pdev, 0);
+ if (irq < 0)
+ return irq;
+
+ ret = devm_request_threaded_irq(dev, irq,
+ mtk_adsp_ipc_irq_handler, mtk_adsp_ipc_handler,
+ IRQF_TRIGGER_NONE, dev_name(dev),
+ mbox->chans);

Please don't break this line, 88 columns is still ok.


After addressing these issues,

Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@xxxxxxxxxxxxx>


Regards,
- Angelo

+ if (ret < 0)
+ return ret;
+
+ /* set adsp mbox channel info */
+ ch_info = devm_kzalloc(dev, sizeof(*ch_info), GFP_KERNEL);
+ if (!ch_info)
+ return -ENOMEM;
+
+ ch_info->va_reg = priv->va_mboxreg;
+ mbox->chans->con_priv = ch_info;
+ platform_set_drvdata(pdev, priv);
+
+ return devm_mbox_controller_register(dev, &priv->mbox);
+}
+
+static const struct of_device_id mtk_adsp_mbox_of_match[] = {
+ { .compatible = "mediatek,mt8195-adsp-mbox", },
+ {},
+};
+MODULE_DEVICE_TABLE(of, mtk_adsp_mbox_of_match);
+
+static struct platform_driver mtk_adsp_ipc_mbox_driver = {
+ .probe = mtk_adsp_mbox_probe,
+ .driver = {
+ .name = "mtk_adsp_mbox",
+ .of_match_table = mtk_adsp_mbox_of_match,
+ },
+};
+module_platform_driver(mtk_adsp_ipc_mbox_driver);
+
+MODULE_AUTHOR("Allen-KH Cheng <Allen-KH.Cheng@xxxxxxxxxxxx>");
+MODULE_DESCRIPTION("MTK ADSP mailbox IPC driver");
+MODULE_LICENSE("GPL v2");