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Diffstat (limited to 'drivers/uio/uio_pruss.c')
-rw-r--r--drivers/uio/uio_pruss.c247
1 files changed, 247 insertions, 0 deletions
diff --git a/drivers/uio/uio_pruss.c b/drivers/uio/uio_pruss.c
new file mode 100644
index 0000000..daf6e77
--- /dev/null
+++ b/drivers/uio/uio_pruss.c
@@ -0,0 +1,247 @@
+/*
+ * 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 <mach/sram.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 upto 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;
+ void *sram_vaddr;
+ void *ddr_vaddr;
+ unsigned int hostirq_start;
+ unsigned int pintc_base;
+};
+
+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)
+ sram_free(gdev->sram_vaddr, sram_pool_sz);
+ kfree(gdev->info);
+ clk_put(gdev->pruss_clk);
+ kfree(gdev);
+}
+
+static int __devinit 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->dev.platform_data;
+
+ 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");
+ kfree(gdev->info);
+ kfree(gdev);
+ ret = PTR_ERR(gdev->pruss_clk);
+ 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;
+ }
+
+ gdev->sram_vaddr = sram_alloc(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 __devexit pruss_remove(struct platform_device *dev)
+{
+ struct uio_pruss_dev *gdev = platform_get_drvdata(dev);
+
+ pruss_cleanup(dev, gdev);
+ platform_set_drvdata(dev, NULL);
+ return 0;
+}
+
+static struct platform_driver pruss_driver = {
+ .probe = pruss_probe,
+ .remove = __devexit_p(pruss_remove),
+ .driver = {
+ .name = DRV_NAME,
+ .owner = THIS_MODULE,
+ },
+};
+
+static int __init pruss_init_module(void)
+{
+ return platform_driver_register(&pruss_driver);
+}
+
+module_init(pruss_init_module);
+
+static void __exit pruss_exit_module(void)
+{
+ platform_driver_unregister(&pruss_driver);
+}
+
+module_exit(pruss_exit_module);
+
+MODULE_LICENSE("GPL v2");
+MODULE_VERSION(DRV_VERSION);
+MODULE_AUTHOR("Amit Chatterjee <amit.chatterjee@ti.com>");
+MODULE_AUTHOR("Pratheesh Gangadhar <pratheesh@ti.com>");
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