linux/arch/mips/ralink/ill_acc.c
John Crispin 5433acd81e MIPS: ralink: add illegal access driver
These SoCs have a special irq that fires upon an illegal memmory access.

Signed-off-by: John Crispin <blogic@openwrt.org>
Patchwork: http://patchwork.linux-mips.org/patch/8003/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-24 07:45:19 +01:00

88 lines
2.1 KiB
C

/*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 as published
* by the Free Software Foundation.
*
* Copyright (C) 2013 John Crispin <blogic@openwrt.org>
*/
#include <linux/interrupt.h>
#include <linux/of_platform.h>
#include <linux/of_irq.h>
#include <asm/mach-ralink/ralink_regs.h>
#define REG_ILL_ACC_ADDR 0x10
#define REG_ILL_ACC_TYPE 0x14
#define ILL_INT_STATUS BIT(31)
#define ILL_ACC_WRITE BIT(30)
#define ILL_ACC_LEN_M 0xff
#define ILL_ACC_OFF_M 0xf
#define ILL_ACC_OFF_S 16
#define ILL_ACC_ID_M 0x7
#define ILL_ACC_ID_S 8
#define DRV_NAME "ill_acc"
static const char * const ill_acc_ids[] = {
"cpu", "dma", "ppe", "pdma rx", "pdma tx", "pci/e", "wmac", "usb",
};
static irqreturn_t ill_acc_irq_handler(int irq, void *_priv)
{
struct device *dev = (struct device *) _priv;
u32 addr = rt_memc_r32(REG_ILL_ACC_ADDR);
u32 type = rt_memc_r32(REG_ILL_ACC_TYPE);
dev_err(dev, "illegal %s access from %s - addr:0x%08x offset:%d len:%d\n",
(type & ILL_ACC_WRITE) ? ("write") : ("read"),
ill_acc_ids[(type >> ILL_ACC_ID_S) & ILL_ACC_ID_M],
addr, (type >> ILL_ACC_OFF_S) & ILL_ACC_OFF_M,
type & ILL_ACC_LEN_M);
rt_memc_w32(REG_ILL_ACC_TYPE, REG_ILL_ACC_TYPE);
return IRQ_HANDLED;
}
static int __init ill_acc_of_setup(void)
{
struct platform_device *pdev;
struct device_node *np;
int irq;
/* somehow this driver breaks on RT5350 */
if (of_machine_is_compatible("ralink,rt5350-soc"))
return -EINVAL;
np = of_find_compatible_node(NULL, NULL, "ralink,rt3050-memc");
if (!np)
return -EINVAL;
pdev = of_find_device_by_node(np);
if (!pdev) {
pr_err("%s: failed to lookup pdev\n", np->name);
return -EINVAL;
}
irq = irq_of_parse_and_map(np, 0);
if (!irq) {
dev_err(&pdev->dev, "failed to get irq\n");
return -EINVAL;
}
if (request_irq(irq, ill_acc_irq_handler, 0, "ill_acc", &pdev->dev)) {
dev_err(&pdev->dev, "failed to request irq\n");
return -EINVAL;
}
rt_memc_w32(ILL_INT_STATUS, REG_ILL_ACC_TYPE);
dev_info(&pdev->dev, "irq registered\n");
return 0;
}
arch_initcall(ill_acc_of_setup);