[PATCH v2] uio: pruss: Remove this driver

From: Andrew Davis
Date: Wed Apr 10 2024 - 10:54:14 EST

This UIO driver was used to control the PRU processors found on various
TI SoCs. It was created before the Remoteproc framework, but now with
that we have a standard way to program and manage the PRU processors.
The proper PRU Remoteproc driver should be used instead of this driver.

This driver only supported the original class of PRUSS (OMAP-L1xx /
AM17xx / AM18xx / TMS320C674x / DA8xx) but when these platforms were
switched to use Device Tree the support for DT was not added to this
driver and so it is now unused/unusable. Support for these platforms
can be added to the proper PRU Remoteproc driver if ever needed.

Remove this driver.

Signed-off-by: Andrew Davis <afd@xxxxxx>
---

Changes for v2:
- Simply remove the whole driver as discussed here[0]

[0] https://lore.kernel.org/lkml/20240325210045.153827-1-afd@xxxxxx/T/

drivers/uio/Kconfig | 18 --
drivers/uio/Makefile | 1 -
drivers/uio/uio_pruss.c | 255 ------------------------
include/linux/platform_data/uio_pruss.h | 18 --
4 files changed, 292 deletions(-)
delete mode 100644 drivers/uio/uio_pruss.c
delete mode 100644 include/linux/platform_data/uio_pruss.h

diff --git a/drivers/uio/Kconfig b/drivers/uio/Kconfig
index 2e16c5338e5b1..b060dcd7c6350 100644
--- a/drivers/uio/Kconfig
+++ b/drivers/uio/Kconfig
@@ -125,24 +125,6 @@ config UIO_FSL_ELBC_GPCM_NETX5152
Information about this hardware can be found at:
http://www.hilscher.com/netx

-config UIO_PRUSS
- tristate "Texas Instruments PRUSS driver"
- select GENERIC_ALLOCATOR
- depends on HAS_IOMEM && HAS_DMA
- help
- PRUSS driver for OMAPL138/DA850/AM18XX devices
- PRUSS driver requires user space components, examples and user space
- driver is available from below SVN repo - you may use anonymous login
-
- https://gforge.ti.com/gf/project/pru_sw/
-
- More info on API is available at below wiki
-
- http://processors.wiki.ti.com/index.php/PRU_Linux_Application_Loader
-
- To compile this driver as a module, choose M here: the module
- will be called uio_pruss.
-
config UIO_MF624
tristate "Humusoft MF624 DAQ PCI card driver"
depends on PCI
diff --git a/drivers/uio/Makefile b/drivers/uio/Makefile
index f2f416a142286..1c5f3b5a95cf5 100644
--- a/drivers/uio/Makefile
+++ b/drivers/uio/Makefile
@@ -7,7 +7,6 @@ obj-$(CONFIG_UIO_AEC) += uio_aec.o
obj-$(CONFIG_UIO_SERCOS3) += uio_sercos3.o
obj-$(CONFIG_UIO_PCI_GENERIC) += uio_pci_generic.o
obj-$(CONFIG_UIO_NETX) += uio_netx.o
-obj-$(CONFIG_UIO_PRUSS) += uio_pruss.o
obj-$(CONFIG_UIO_MF624) += uio_mf624.o
obj-$(CONFIG_UIO_FSL_ELBC_GPCM) += uio_fsl_elbc_gpcm.o
obj-$(CONFIG_UIO_HV_GENERIC) += uio_hv_generic.o
diff --git a/drivers/uio/uio_pruss.c b/drivers/uio/uio_pruss.c
deleted file mode 100644
index f67881cba645b..0000000000000
--- a/drivers/uio/uio_pruss.c
+++ /dev/null
@@ -1,255 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-only
-/*
- * Programmable Real-Time Unit Sub System (PRUSS) UIO driver (uio_pruss)
- *
- * This driver exports PRUSS host event out interrupts and PRUSS, L3 RAM,
- * and DDR RAM to user space for applications interacting with PRUSS firmware
- *
- * Copyright (C) 2010-11 Texas Instruments Incorporated - http://www.ti.com/
- */
-#include <linux/device.h>
-#include <linux/module.h>
-#include <linux/moduleparam.h>
-#include <linux/platform_device.h>
-#include <linux/uio_driver.h>
-#include <linux/platform_data/uio_pruss.h>
-#include <linux/io.h>
-#include <linux/clk.h>
-#include <linux/dma-mapping.h>
-#include <linux/sizes.h>
-#include <linux/slab.h>
-#include <linux/genalloc.h>
-
-#define DRV_NAME "pruss_uio"
-#define DRV_VERSION "1.0"
-
-static int sram_pool_sz = SZ_16K;
-module_param(sram_pool_sz, int, 0);
-MODULE_PARM_DESC(sram_pool_sz, "sram pool size to allocate ");
-
-static int extram_pool_sz = SZ_256K;
-module_param(extram_pool_sz, int, 0);
-MODULE_PARM_DESC(extram_pool_sz, "external ram pool size to allocate");
-
-/*
- * Host event IRQ numbers from PRUSS - PRUSS can generate up to 8 interrupt
- * events to AINTC of ARM host processor - which can be used for IPC b/w PRUSS
- * firmware and user space application, async notification from PRU firmware
- * to user space application
- * 3 PRU_EVTOUT0
- * 4 PRU_EVTOUT1
- * 5 PRU_EVTOUT2
- * 6 PRU_EVTOUT3
- * 7 PRU_EVTOUT4
- * 8 PRU_EVTOUT5
- * 9 PRU_EVTOUT6
- * 10 PRU_EVTOUT7
-*/
-#define MAX_PRUSS_EVT 8
-
-#define PINTC_HIDISR 0x0038
-#define PINTC_HIPIR 0x0900
-#define HIPIR_NOPEND 0x80000000
-#define PINTC_HIER 0x1500
-
-struct uio_pruss_dev {
- struct uio_info *info;
- struct clk *pruss_clk;
- dma_addr_t sram_paddr;
- dma_addr_t ddr_paddr;
- void __iomem *prussio_vaddr;
- unsigned long sram_vaddr;
- void *ddr_vaddr;
- unsigned int hostirq_start;
- unsigned int pintc_base;
- struct gen_pool *sram_pool;
-};
-
-static irqreturn_t pruss_handler(int irq, struct uio_info *info)
-{
- struct uio_pruss_dev *gdev = info->priv;
- int intr_bit = (irq - gdev->hostirq_start + 2);
- int val, intr_mask = (1 << intr_bit);
- void __iomem *base = gdev->prussio_vaddr + gdev->pintc_base;
- void __iomem *intren_reg = base + PINTC_HIER;
- void __iomem *intrdis_reg = base + PINTC_HIDISR;
- void __iomem *intrstat_reg = base + PINTC_HIPIR + (intr_bit << 2);
-
- val = ioread32(intren_reg);
- /* Is interrupt enabled and active ? */
- if (!(val & intr_mask) && (ioread32(intrstat_reg) & HIPIR_NOPEND))
- return IRQ_NONE;
- /* Disable interrupt */
- iowrite32(intr_bit, intrdis_reg);
- return IRQ_HANDLED;
-}
-
-static void pruss_cleanup(struct device *dev, struct uio_pruss_dev *gdev)
-{
- int cnt;
- struct uio_info *p = gdev->info;
-
- for (cnt = 0; cnt < MAX_PRUSS_EVT; cnt++, p++) {
- uio_unregister_device(p);
- }
- iounmap(gdev->prussio_vaddr);
- if (gdev->ddr_vaddr) {
- dma_free_coherent(dev, extram_pool_sz, gdev->ddr_vaddr,
- gdev->ddr_paddr);
- }
- if (gdev->sram_vaddr)
- gen_pool_free(gdev->sram_pool,
- gdev->sram_vaddr,
- sram_pool_sz);
- clk_disable(gdev->pruss_clk);
-}
-
-static int pruss_probe(struct platform_device *pdev)
-{
- struct uio_info *p;
- struct uio_pruss_dev *gdev;
- struct resource *regs_prussio;
- struct device *dev = &pdev->dev;
- int ret, cnt, i, len;
- struct uio_pruss_pdata *pdata = dev_get_platdata(dev);
-
- gdev = devm_kzalloc(dev, sizeof(struct uio_pruss_dev), GFP_KERNEL);
- if (!gdev)
- return -ENOMEM;
-
- gdev->info = devm_kcalloc(dev, MAX_PRUSS_EVT, sizeof(*p), GFP_KERNEL);
- if (!gdev->info)
- return -ENOMEM;
-
- /* Power on PRU in case its not done as part of boot-loader */
- gdev->pruss_clk = devm_clk_get(dev, "pruss");
- if (IS_ERR(gdev->pruss_clk)) {
- dev_err(dev, "Failed to get clock\n");
- return PTR_ERR(gdev->pruss_clk);
- }
-
- ret = clk_enable(gdev->pruss_clk);
- if (ret) {
- dev_err(dev, "Failed to enable clock\n");
- return ret;
- }
-
- regs_prussio = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- if (!regs_prussio) {
- dev_err(dev, "No PRUSS I/O resource specified\n");
- ret = -EIO;
- goto err_clk_disable;
- }
-
- if (!regs_prussio->start) {
- dev_err(dev, "Invalid memory resource\n");
- ret = -EIO;
- goto err_clk_disable;
- }
-
- if (pdata->sram_pool) {
- gdev->sram_pool = pdata->sram_pool;
- gdev->sram_vaddr =
- (unsigned long)gen_pool_dma_alloc(gdev->sram_pool,
- sram_pool_sz, &gdev->sram_paddr);
- if (!gdev->sram_vaddr) {
- dev_err(dev, "Could not allocate SRAM pool\n");
- ret = -ENOMEM;
- goto err_clk_disable;
- }
- }
-
- gdev->ddr_vaddr = dma_alloc_coherent(dev, extram_pool_sz,
- &(gdev->ddr_paddr), GFP_KERNEL | GFP_DMA);
- if (!gdev->ddr_vaddr) {
- dev_err(dev, "Could not allocate external memory\n");
- ret = -ENOMEM;
- goto err_free_sram;
- }
-
- len = resource_size(regs_prussio);
- gdev->prussio_vaddr = ioremap(regs_prussio->start, len);
- if (!gdev->prussio_vaddr) {
- dev_err(dev, "Can't remap PRUSS I/O address range\n");
- ret = -ENOMEM;
- goto err_free_ddr_vaddr;
- }
-
- ret = platform_get_irq(pdev, 0);
- if (ret < 0)
- goto err_unmap;
-
- gdev->hostirq_start = ret;
- gdev->pintc_base = pdata->pintc_base;
-
- for (cnt = 0, p = gdev->info; cnt < MAX_PRUSS_EVT; cnt++, p++) {
- p->mem[0].addr = regs_prussio->start;
- p->mem[0].size = resource_size(regs_prussio);
- p->mem[0].memtype = UIO_MEM_PHYS;
-
- p->mem[1].addr = gdev->sram_paddr;
- p->mem[1].size = sram_pool_sz;
- p->mem[1].memtype = UIO_MEM_PHYS;
-
- p->mem[2].addr = (uintptr_t) gdev->ddr_vaddr;
- p->mem[2].dma_addr = gdev->ddr_paddr;
- p->mem[2].size = extram_pool_sz;
- p->mem[2].memtype = UIO_MEM_DMA_COHERENT;
- p->mem[2].dma_device = dev;
-
- p->name = devm_kasprintf(dev, GFP_KERNEL, "pruss_evt%d", cnt);
- p->version = DRV_VERSION;
-
- /* Register PRUSS IRQ lines */
- p->irq = gdev->hostirq_start + cnt;
- p->handler = pruss_handler;
- p->priv = gdev;
-
- ret = uio_register_device(dev, p);
- if (ret < 0)
- goto err_unloop;
- }
-
- platform_set_drvdata(pdev, gdev);
- return 0;
-
-err_unloop:
- for (i = 0, p = gdev->info; i < cnt; i++, p++) {
- uio_unregister_device(p);
- }
-err_unmap:
- iounmap(gdev->prussio_vaddr);
-err_free_ddr_vaddr:
- dma_free_coherent(dev, extram_pool_sz, gdev->ddr_vaddr,
- gdev->ddr_paddr);
-err_free_sram:
- if (pdata->sram_pool)
- gen_pool_free(gdev->sram_pool, gdev->sram_vaddr, sram_pool_sz);
-err_clk_disable:
- clk_disable(gdev->pruss_clk);
-
- return ret;
-}
-
-static int pruss_remove(struct platform_device *dev)
-{
- struct uio_pruss_dev *gdev = platform_get_drvdata(dev);
-
- pruss_cleanup(&dev->dev, gdev);
- return 0;
-}
-
-static struct platform_driver pruss_driver = {
- .probe = pruss_probe,
- .remove = pruss_remove,
- .driver = {
- .name = DRV_NAME,
- },
-};
-
-module_platform_driver(pruss_driver);
-
-MODULE_LICENSE("GPL v2");
-MODULE_VERSION(DRV_VERSION);
-MODULE_AUTHOR("Amit Chatterjee <amit.chatterjee@xxxxxx>");
-MODULE_AUTHOR("Pratheesh Gangadhar <pratheesh@xxxxxx>");
diff --git a/include/linux/platform_data/uio_pruss.h b/include/linux/platform_data/uio_pruss.h
deleted file mode 100644
index f76fa393b8023..0000000000000
--- a/include/linux/platform_data/uio_pruss.h
+++ /dev/null
@@ -1,18 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0-only */
-/*
- * include/linux/platform_data/uio_pruss.h
- *
- * Platform data for uio_pruss driver
- *
- * Copyright (C) 2010-11 Texas Instruments Incorporated - https://www.ti.com/
- */
-
-#ifndef _UIO_PRUSS_H_
-#define _UIO_PRUSS_H_
-
-/* To configure the PRUSS INTC base offset for UIO driver */
-struct uio_pruss_pdata {
- u32 pintc_base;
- struct gen_pool *sram_pool;
-};
-#endif /* _UIO_PRUSS_H_ */
--
2.39.2