drivers/uio/uio_pruss.c - linux - Git at Google

 // 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;
 	}

 	gdev->pintc_base = pdata->pintc_base;
 	gdev->hostirq_start = platform_get_irq(pdev, 0);

 	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 = gdev->ddr_paddr;
 		p->mem[2].size = extram_pool_sz;
 		p->mem[2].memtype = UIO_MEM_PHYS;

 		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);
 	}
 	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@ti.com>");
 MODULE_AUTHOR("Pratheesh Gangadhar <pratheesh@ti.com>");
	// 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;
	}

	gdev->pintc_base = pdata->pintc_base;
	gdev->hostirq_start = platform_get_irq(pdev, 0);

	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 = gdev->ddr_paddr;
	p->mem[2].size = extram_pool_sz;
	p->mem[2].memtype = UIO_MEM_PHYS;

	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);
	}
	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@ti.com>");
	MODULE_AUTHOR("Pratheesh Gangadhar <pratheesh@ti.com>");