Commit 5433acd8 authored by John Crispin's avatar John Crispin Committed by Ralf Baechle
Browse files

MIPS: ralink: add illegal access driver 



These SoCs have a special irq that fires upon an illegal memmory access.

Signed-off-by: default avatarJohn Crispin <blogic@openwrt.org>
Patchwork: http://patchwork.linux-mips.org/patch/8003/


Signed-off-by: default avatarRalf Baechle <ralf@linux-mips.org>
parent 47e14d66

arch/mips/ralink/Makefile

+2 −0
Original line number Diff line number Diff line
@@ -10,6 +10,8 @@ obj-y := prom.o of.o reset.o clk.o irq.o timer.o 


obj-$(CONFIG_CLKEVT_RT3352) += cevt-rt3352.o



obj-$(CONFIG_RALINK_ILL_ACC) += ill_acc.o



obj-$(CONFIG_SOC_RT288X) += rt288x.o

obj-$(CONFIG_SOC_RT305X) += rt305x.o

obj-$(CONFIG_SOC_RT3883) += rt3883.o

arch/mips/ralink/ill_acc.c

0 → 100644
+87 −0
Original line number Diff line number Diff line 
/*

 * 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);