diff options
Diffstat (limited to 'drivers/uio/uio_pruss.c')
| -rw-r--r-- | drivers/uio/uio_pruss.c | 242 |
1 files changed, 242 insertions, 0 deletions
diff --git a/drivers/uio/uio_pruss.c b/drivers/uio/uio_pruss.c new file mode 100644 index 00000000000..96c4a19b191 --- /dev/null +++ b/drivers/uio/uio_pruss.c @@ -0,0 +1,242 @@ +/* + * 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 platform_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->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 *dev) +{ + struct uio_info *p; + struct uio_pruss_dev *gdev; + struct resource *regs_prussio; + int ret = -ENODEV, cnt = 0, len; + struct uio_pruss_pdata *pdata = dev_get_platdata(&dev->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->dev, "pruss"); + if (IS_ERR(gdev->pruss_clk)) { + dev_err(&dev->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(dev, IORESOURCE_MEM, 0); + if (!regs_prussio) { + dev_err(&dev->dev, "No PRUSS I/O resource specified\n"); + goto out_free; + } + + if (!regs_prussio->start) { + dev_err(&dev->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->dev, "Could not allocate SRAM pool\n"); + goto out_free; + } + } + + gdev->ddr_vaddr = dma_alloc_coherent(&dev->dev, extram_pool_sz, + &(gdev->ddr_paddr), GFP_KERNEL | GFP_DMA); + if (!gdev->ddr_vaddr) { + dev_err(&dev->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->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(dev, 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->dev, p); + if (ret < 0) + goto out_free; + } + + platform_set_drvdata(dev, 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, gdev); + return 0; +} + +static struct platform_driver pruss_driver = { + .probe = pruss_probe, + .remove = pruss_remove, + .driver = { + .name = DRV_NAME, + .owner = THIS_MODULE, + }, +}; + +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>"); |