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[v10,1/1] PRUSS UIO driver support

Message ID 1299213772-21931-2-git-send-email-pratheesh@ti.com (mailing list archive)
State Changes Requested
Headers show

Commit Message

Pratheesh Gangadhar March 4, 2011, 4:42 a.m. UTC
None
diff mbox

Patch

diff --git a/drivers/uio/Kconfig b/drivers/uio/Kconfig
index bb44079..6f3ea9b 100644
--- a/drivers/uio/Kconfig
+++ b/drivers/uio/Kconfig
@@ -94,4 +94,21 @@  config UIO_NETX
 	  To compile this driver as a module, choose M here; the module
 	  will be called uio_netx.
 
+config UIO_PRUSS
+	tristate "Texas Instruments PRUSS driver"
+	depends on ARCH_DAVINCI_DA850
+	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.
+
 endif
diff --git a/drivers/uio/Makefile b/drivers/uio/Makefile
index 18fd818..d4dd9a5 100644
--- a/drivers/uio/Makefile
+++ b/drivers/uio/Makefile
@@ -6,3 +6,4 @@  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
diff --git a/drivers/uio/uio_pruss.c b/drivers/uio/uio_pruss.c
new file mode 100644
index 0000000..719e73d
--- /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/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>");
diff --git a/include/linux/uio_pruss.h b/include/linux/uio_pruss.h
new file mode 100644
index 0000000..8c9b2c9
--- /dev/null
+++ b/include/linux/uio_pruss.h
@@ -0,0 +1,25 @@ 
+/*
+ * include/linux/uio_pruss.h
+ *
+ * Platform data for uio_pruss driver
+ *
+ * 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.
+ */
+
+#ifndef _UIO_PRUSS_H_
+#define _UIO_PRUSS_H_
+
+/* Used to configure the PRUSS INTC base offset for UIO driver */
+struct uio_pruss_pdata {
+	u32	pintc_base;
+};
+#endif /* _LINUX_UIO_PRUSS_H_ */