/*
* 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/
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation version 2.
*
* This program is distributed "as is" WITHOUT ANY WARRANTY of any
* kind, whether express or implied; without even the implied warranty
* of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#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/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);
kfree(p->name);
}
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);
kfree(gdev->info);
clk_put(gdev->pruss_clk);
kfree(gdev);
}
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 = -ENODEV, cnt = 0, len;
struct uio_pruss_pdata *pdata = dev_get_platdata(dev);
gdev = kzalloc(sizeof(struct uio_pruss_dev), GFP_KERNEL);
if (!gdev)
return -ENOMEM;
gdev->info = kzalloc(sizeof(*p) * MAX_PRUSS_EVT, GFP_KERNEL);
if (!gdev->info) {
kfree(gdev);
return -ENOMEM;
}
/* Power on PRU in case its not done as part of boot-loader */
gdev->pruss_clk = clk_get(dev, "pruss");
if (IS_ERR(gdev->pruss_clk)) {
dev_err(dev, "Failed to get clock\n");
ret = PTR_ERR(gdev->pruss_clk);
kfree(gdev->info);
kfree(gdev);
return ret;
} else {
clk_enable(gdev->pruss_clk);
}
regs_prussio = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!regs_prussio) {
dev_err(dev, "No PRUSS I/O resource specified\n");
goto out_free;
}
if (!regs_prussio->start) {
dev_err(dev, "Invalid memory resource\n");
goto out_free;
}
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");
goto out_free;
}
}
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");
goto out_free;
}
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");
goto out_free;
}
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 = kasprintf(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 out_free;
}
platform_set_drvdata(pdev, gdev);
return 0;
out_free:
pruss_cleanup(dev, gdev);
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>");
