OMAP4: l3: Introduce l3-interconnect error handling driver

The driver provides the information regarding the ocp errors
that gets logged in the interconnect. The error information
gives the detail regarding the target that was attempted
to be accessed and its corresponding address.

Signed-off-by: sricharan <r.sricharan@ti.com>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Acked-by: Benoit Cousson <b-cousson@ti.com>

1 files changed, 253 insertions, 0 deletions

diff --git a/arch/arm/mach-omap2/omap_l3_noc.c b/arch/arm/mach-omap2/omap_l3_noc.c
new file mode 100644
index 0000000..82632c2
--- /dev/null
+++ b/arch/arm/mach-omap2/omap_l3_noc.c
@@ -0,0 +1,253 @@
+/*
+  * OMAP4XXX L3 Interconnect error handling driver
+  *
+  * Copyright (C) 2011 Texas Corporation
+  *	Santosh Shilimkar <santosh.shilimkar@ti.com>
+  *	Sricharan <r.sricharan@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; either version 2 of the License, or
+  * (at your option) any later version.
+  *
+  * This program is distributed in the hope that it will be useful,
+  * but WITHOUT ANY WARRANTY; without even the implied warranty of
+  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  * GNU General Public License for more details.
+  *
+  * You should have received a copy of the GNU General Public License
+  * along with this program; if not, write to the Free Software
+  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
+  * USA
+  */
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/platform_device.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+
+#include "omap_l3_noc.h"
+
+/*
+ * Interrupt Handler for L3 error detection.
+ *	1) Identify the L3 clockdomain partition to which the error belongs to.
+ *	2) Identify the slave where the error information is logged
+ *	3) Print the logged information.
+ *	4) Add dump stack to provide kernel trace.
+ *
+ * Two Types of errors :
+ *	1) Custom errors in L3 :
+ *		Target like DMM/FW/EMIF generates SRESP=ERR error
+ *	2) Standard L3 error:
+ *		- Unsupported CMD.
+ *			L3 tries to access target while it is idle
+ *		- OCP disconnect.
+ *		- Address hole error:
+ *			If DSS/ISS/FDIF/USBHOSTFS access a target where they
+ *			do not have connectivity, the error is logged in
+ *			their default target which is DMM2.
+ *
+ *	On High Secure devices, firewall errors are possible and those
+ *	can be trapped as well. But the trapping is implemented as part
+ *	secure software and hence need not be implemented here.
+ */
+static irqreturn_t l3_interrupt_handler(int irq, void *_l3)
+{
+
+	struct omap4_l3		*l3 = _l3;
+	int inttype, i, j;
+	int err_src = 0;
+	u32 std_err_main_addr, std_err_main, err_reg;
+	u32 base, slave_addr, clear;
+	char *source_name;
+
+	/* Get the Type of interrupt */
+	if (irq == l3->app_irq)
+		inttype = L3_APPLICATION_ERROR;
+	else
+		inttype = L3_DEBUG_ERROR;
+
+	for (i = 0; i < L3_MODULES; i++) {
+		/*
+		 * Read the regerr register of the clock domain
+		 * to determine the source
+		 */
+		base = (u32)l3->l3_base[i];
+		err_reg =  readl(base + l3_flagmux[i] + (inttype << 3));
+
+		/* Get the corresponding error and analyse */
+		if (err_reg) {
+			/* Identify the source from control status register */
+			for (j = 0; !(err_reg & (1 << j)); j++)
+									;
+
+			err_src = j;
+			/* Read the stderrlog_main_source from clk domain */
+			std_err_main_addr = base + (*(l3_targ[i] + err_src));
+			std_err_main =  readl(std_err_main_addr);
+
+			switch ((std_err_main & CUSTOM_ERROR)) {
+			case STANDARD_ERROR:
+				source_name =
+				l3_targ_stderrlog_main_name[i][err_src];
+
+				slave_addr = std_err_main_addr +
+						L3_SLAVE_ADDRESS_OFFSET;
+				WARN(true, "L3 standard error: SOURCE:%s at address 0x%x\n",
+					source_name, readl(slave_addr));
+				/* clear the std error log*/
+				clear = std_err_main | CLEAR_STDERR_LOG;
+				writel(clear, std_err_main_addr);
+				break;
+
+			case CUSTOM_ERROR:
+				source_name =
+				l3_targ_stderrlog_main_name[i][err_src];
+
+				WARN(true, "CUSTOM SRESP error with SOURCE:%s\n",
+							source_name);
+				/* clear the std error log*/
+				clear = std_err_main | CLEAR_STDERR_LOG;
+				writel(clear, std_err_main_addr);
+				break;
+
+			default:
+				/* Nothing to be handled here as of now */
+				break;
+			}
+		/* Error found so break the for loop */
+		break;
+		}
+	}
+	return IRQ_HANDLED;
+}
+
+static int __init omap4_l3_probe(struct platform_device *pdev)
+{
+	static struct omap4_l3		*l3;
+	struct resource		*res;
+	int			ret;
+	int			irq;
+
+	l3 = kzalloc(sizeof(*l3), GFP_KERNEL);
+	if (!l3)
+		ret = -ENOMEM;
+
+	platform_set_drvdata(pdev, l3);
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res) {
+		dev_err(&pdev->dev, "couldn't find resource 0\n");
+		ret = -ENODEV;
+		goto err1;
+	}
+
+	l3->l3_base[0] = ioremap(res->start, resource_size(res));
+	if (!(l3->l3_base[0])) {
+		dev_err(&pdev->dev, "ioremap failed\n");
+		ret = -ENOMEM;
+		goto err2;
+	}
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+	if (!res) {
+		dev_err(&pdev->dev, "couldn't find resource 1\n");
+		ret = -ENODEV;
+		goto err3;
+	}
+
+	l3->l3_base[1] = ioremap(res->start, resource_size(res));
+	if (!(l3->l3_base[1])) {
+		dev_err(&pdev->dev, "ioremap failed\n");
+		ret = -ENOMEM;
+		goto err4;
+	}
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 2);
+	if (!res) {
+		dev_err(&pdev->dev, "couldn't find resource 2\n");
+		ret = -ENODEV;
+		goto err5;
+	}
+
+	l3->l3_base[2] = ioremap(res->start, resource_size(res));
+	if (!(l3->l3_base[2])) {
+		dev_err(&pdev->dev, "ioremap failed\n");
+		ret = -ENOMEM;
+		goto err6;
+	}
+
+	/*
+	 * Setup interrupt Handlers
+	 */
+	irq = platform_get_irq(pdev, 0);
+	ret = request_irq(irq,
+			l3_interrupt_handler,
+			IRQF_DISABLED, "l3-dbg-irq", l3);
+	if (ret) {
+		pr_crit("L3: request_irq failed to register for 0x%x\n",
+					 OMAP44XX_IRQ_L3_DBG);
+		goto err7;
+	}
+	l3->debug_irq = irq;
+
+	irq = platform_get_irq(pdev, 1);
+	ret = request_irq(irq,
+			l3_interrupt_handler,
+			IRQF_DISABLED, "l3-app-irq", l3);
+	if (ret) {
+		pr_crit("L3: request_irq failed to register for 0x%x\n",
+					 OMAP44XX_IRQ_L3_APP);
+		goto err8;
+	}
+	l3->app_irq = irq;
+
+	goto err0;
+err8:
+err7:
+	iounmap(l3->l3_base[2]);
+err6:
+err5:
+	iounmap(l3->l3_base[1]);
+err4:
+err3:
+	iounmap(l3->l3_base[0]);
+err2:
+err1:
+	kfree(l3);
+err0:
+	return ret;
+}
+
+static int __exit omap4_l3_remove(struct platform_device *pdev)
+{
+	struct omap4_l3         *l3 = platform_get_drvdata(pdev);
+
+	free_irq(l3->app_irq, l3);
+	free_irq(l3->debug_irq, l3);
+	iounmap(l3->l3_base[0]);
+	iounmap(l3->l3_base[1]);
+	iounmap(l3->l3_base[2]);
+	kfree(l3);
+
+	return 0;
+}
+
+static struct platform_driver omap4_l3_driver = {
+	.remove		= __exit_p(omap4_l3_remove),
+	.driver		= {
+	.name		= "omap_l3_noc",
+	},
+};
+
+static int __init omap4_l3_init(void)
+{
+	return platform_driver_probe(&omap4_l3_driver, omap4_l3_probe);
+}
+postcore_initcall_sync(omap4_l3_init);
+
+static void __exit omap4_l3_exit(void)
+{
+	platform_driver_unregister(&omap4_l3_driver);
+}
+module_exit(omap4_l3_exit);