OMAP3: l3: Introduce l3-interconnect error handling driver

The driver provides the information regarding the ocp errors
that gets logged in the interconnect.The error info provides
the details regarding the master or the target that
generated the error, type of error and the corresponding address.
The stack dump is also provided.

Signed-off-by: sricharan <r.sricharan@ti.com>
[r.sricharan@ti.com: Enhacements, major cleanup and made it functional]
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
[santosh.shilimkar@ti.com: Driver design changes as per OMAP4 version]
Signed-off-by: Felipe Balbi <balbi@ti.com>
[balbi@ti.com: Initial version of the driver]
Acked-by: Benoit Cousson <b-cousson@ti.com>

1 files changed, 314 insertions, 0 deletions

diff --git a/arch/arm/mach-omap2/omap_l3_smx.c b/arch/arm/mach-omap2/omap_l3_smx.c
new file mode 100644
index 0000000..265bff3
--- /dev/null
+++ b/arch/arm/mach-omap2/omap_l3_smx.c
@@ -0,0 +1,314 @@
+ /*
+  * OMAP3XXX L3 Interconnect Driver
+  *
+  * Copyright (C) 2011 Texas Corporation
+  *	Felipe Balbi <balbi@ti.com>
+  *	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/kernel.h>
+#include <linux/slab.h>
+#include <linux/platform_device.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include "omap_l3_smx.h"
+
+static inline u64 omap3_l3_readll(void __iomem *base, u16 reg)
+{
+	return __raw_readll(base + reg);
+}
+
+static inline void omap3_l3_writell(void __iomem *base, u16 reg, u64 value)
+{
+	__raw_writell(value, base + reg);
+}
+
+static inline enum omap3_l3_code omap3_l3_decode_error_code(u64 error)
+{
+	return (error & 0x0f000000) >> L3_ERROR_LOG_CODE;
+}
+
+static inline u32 omap3_l3_decode_addr(u64 error_addr)
+{
+	return error_addr & 0xffffffff;
+}
+
+static inline unsigned omap3_l3_decode_cmd(u64 error)
+{
+	return (error & 0x07) >> L3_ERROR_LOG_CMD;
+}
+
+static inline enum omap3_l3_initiator_id omap3_l3_decode_initid(u64 error)
+{
+	return (error & 0xff00) >> L3_ERROR_LOG_INITID;
+}
+
+static inline unsigned omap3_l3_decode_req_info(u64 error)
+{
+	return (error >> 32) & 0xffff;
+}
+
+static char *omap3_l3_code_string(u8 code)
+{
+	switch (code) {
+	case OMAP_L3_CODE_NOERROR:
+		return "No Error";
+	case OMAP_L3_CODE_UNSUP_CMD:
+		return "Unsupported Command";
+	case OMAP_L3_CODE_ADDR_HOLE:
+		return "Address Hole";
+	case OMAP_L3_CODE_PROTECT_VIOLATION:
+		return "Protection Violation";
+	case OMAP_L3_CODE_IN_BAND_ERR:
+		return "In-band Error";
+	case OMAP_L3_CODE_REQ_TOUT_NOT_ACCEPT:
+		return "Request Timeout Not Accepted";
+	case OMAP_L3_CODE_REQ_TOUT_NO_RESP:
+		return "Request Timeout, no response";
+	default:
+		return "UNKNOWN error";
+	}
+}
+
+static char *omap3_l3_initiator_string(u8 initid)
+{
+	switch (initid) {
+	case OMAP_L3_LCD:
+		return "LCD";
+	case OMAP_L3_SAD2D:
+		return "SAD2D";
+	case OMAP_L3_IA_MPU_SS_1:
+	case OMAP_L3_IA_MPU_SS_2:
+	case OMAP_L3_IA_MPU_SS_3:
+	case OMAP_L3_IA_MPU_SS_4:
+	case OMAP_L3_IA_MPU_SS_5:
+		return "MPU";
+	case OMAP_L3_IA_IVA_SS_1:
+	case OMAP_L3_IA_IVA_SS_2:
+	case OMAP_L3_IA_IVA_SS_3:
+		return "IVA_SS";
+	case OMAP_L3_IA_IVA_SS_DMA_1:
+	case OMAP_L3_IA_IVA_SS_DMA_2:
+	case OMAP_L3_IA_IVA_SS_DMA_3:
+	case OMAP_L3_IA_IVA_SS_DMA_4:
+	case OMAP_L3_IA_IVA_SS_DMA_5:
+	case OMAP_L3_IA_IVA_SS_DMA_6:
+		return "IVA_SS_DMA";
+	case OMAP_L3_IA_SGX:
+		return "SGX";
+	case OMAP_L3_IA_CAM_1:
+	case OMAP_L3_IA_CAM_2:
+	case OMAP_L3_IA_CAM_3:
+		return "CAM";
+	case OMAP_L3_IA_DAP:
+		return "DAP";
+	case OMAP_L3_SDMA_WR_1:
+	case OMAP_L3_SDMA_WR_2:
+		return "SDMA_WR";
+	case OMAP_L3_SDMA_RD_1:
+	case OMAP_L3_SDMA_RD_2:
+	case OMAP_L3_SDMA_RD_3:
+	case OMAP_L3_SDMA_RD_4:
+		return "SDMA_RD";
+	case OMAP_L3_USBOTG:
+		return "USB_OTG";
+	case OMAP_L3_USBHOST:
+		return "USB_HOST";
+	default:
+		return "UNKNOWN Initiator";
+	}
+}
+
+/**
+ * omap3_l3_block_irq - handles a register block's irq
+ * @l3: struct omap3_l3 *
+ * @base: register block base address
+ * @error: L3_ERROR_LOG register of our block
+ *
+ * Called in hard-irq context. Caller should take care of locking
+ *
+ * OMAP36xx TRM gives, on page 2001, Figure 9-10, the Typical Error
+ * Analysis Sequence, we are following that sequence here, please
+ * refer to that Figure for more information on the subject.
+ */
+static irqreturn_t omap3_l3_block_irq(struct omap3_l3 *l3,
+					u64 error, int error_addr)
+{
+	u8                      code = omap3_l3_decode_error_code(error);
+	u8                      initid = omap3_l3_decode_initid(error);
+	u8                      multi = error & L3_ERROR_LOG_MULTI;
+	u32			address = omap3_l3_decode_addr(error_addr);
+
+	WARN(true, "%s Error seen by %s %s at address %x\n",
+				 omap3_l3_code_string(code),
+			  omap3_l3_initiator_string(initid),
+			     multi ? "Multiple Errors" : "",
+						   address);
+
+	return IRQ_HANDLED;
+}
+
+static irqreturn_t omap3_l3_app_irq(int irq, void *_l3)
+{
+	struct omap3_l3         *l3 = _l3;
+
+	u64                     status, clear;
+	u64                     error;
+	u64			error_addr;
+	u64			err_source = 0;
+	void			__iomem *base;
+	int			int_type;
+
+	irqreturn_t             ret = IRQ_NONE;
+
+	if (irq == l3->app_irq)
+		int_type = L3_APPLICATION_ERROR;
+	else
+		int_type = L3_DEBUG_ERROR;
+
+	if (!int_type) {
+		status = omap3_l3_readll(l3->rt, L3_SI_FLAG_STATUS_0);
+		/*
+		 * if we have a timeout error, there's nothing we can
+		 * do besides rebooting the board. So let's BUG on any
+		 * of such errors and handle the others. timeout error
+		 * is severe and not expected to occur.
+		 */
+		BUG_ON(status & L3_STATUS_0_TIMEOUT_MASK);
+	} else {
+		status = omap3_l3_readll(l3->rt, L3_SI_FLAG_STATUS_1);
+		/* No timeout error for debug sources */
+	}
+
+	base = ((l3->rt) + (*(omap3_l3_bases[int_type] + err_source)));
+
+	/* identify the error source */
+	for (err_source = 0; !(status & (1 << err_source)); err_source++)
+									;
+	error = omap3_l3_readll(base, L3_ERROR_LOG);
+
+	if (error) {
+		error_addr = omap3_l3_readll(base, L3_ERROR_LOG_ADDR);
+
+		ret |= omap3_l3_block_irq(l3, error, error_addr);
+	}
+
+	/* Clear the status register */
+	clear = ((L3_AGENT_STATUS_CLEAR_IA << int_type) |
+		 (L3_AGENT_STATUS_CLEAR_TA));
+
+	omap3_l3_writell(base, L3_AGENT_STATUS, clear);
+
+	/* clear the error log register */
+	omap3_l3_writell(base, L3_ERROR_LOG, error);
+
+	return ret;
+}
+
+static int __init omap3_l3_probe(struct platform_device *pdev)
+{
+	struct omap3_l3         *l3;
+	struct resource         *res;
+	int                     ret;
+	int                     irq;
+
+	l3 = kzalloc(sizeof(*l3), GFP_KERNEL);
+	if (!l3) {
+		ret = -ENOMEM;
+		goto err0;
+	}
+
+	platform_set_drvdata(pdev, l3);
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res) {
+		dev_err(&pdev->dev, "couldn't find resource\n");
+		ret = -ENODEV;
+		goto err1;
+	}
+	l3->rt = ioremap(res->start, resource_size(res));
+	if (!(l3->rt)) {
+		dev_err(&pdev->dev, "ioremap failed\n");
+		ret = -ENOMEM;
+		goto err2;
+	}
+
+	irq = platform_get_irq(pdev, 0);
+	ret = request_irq(irq, omap3_l3_app_irq,
+		IRQF_DISABLED | IRQF_TRIGGER_RISING,
+		"l3-debug-irq", l3);
+	if (ret) {
+		dev_err(&pdev->dev, "couldn't request debug irq\n");
+		goto err3;
+	}
+	l3->debug_irq = irq;
+
+	irq = platform_get_irq(pdev, 1);
+	ret = request_irq(irq, omap3_l3_app_irq,
+		IRQF_DISABLED | IRQF_TRIGGER_RISING,
+		"l3-app-irq", l3);
+
+	if (ret) {
+		dev_err(&pdev->dev, "couldn't request app irq\n");
+		goto err4;
+	}
+
+	l3->app_irq = irq;
+	goto err0;
+
+err4:
+err3:
+	iounmap(l3->rt);
+err2:
+err1:
+	kfree(l3);
+err0:
+	return ret;
+}
+
+static int __exit omap3_l3_remove(struct platform_device *pdev)
+{
+	struct omap3_l3         *l3 = platform_get_drvdata(pdev);
+
+	free_irq(l3->app_irq, l3);
+	free_irq(l3->debug_irq, l3);
+	iounmap(l3->rt);
+	kfree(l3);
+
+	return 0;
+}
+
+static struct platform_driver omap3_l3_driver = {
+	.remove         = __exit_p(omap3_l3_remove),
+	.driver         = {
+	.name   = "omap_l3_smx",
+	},
+};
+
+static int __init omap3_l3_init(void)
+{
+	return platform_driver_probe(&omap3_l3_driver, omap3_l3_probe);
+}
+postcore_initcall_sync(omap3_l3_init);
+
+static void __exit omap3_l3_exit(void)
+{
+	platform_driver_unregister(&omap3_l3_driver);
+}
+module_exit(omap3_l3_exit);