1/*
2 * This program is free software; you can redistribute it and/or modify it
3 * under the terms of the GNU General Public License version 2 as published
4 * by the Free Software Foundation.
5 *
6 * Copyright (C) 2013 John Crispin <blogic@openwrt.org>
7 */
8
9#include <linux/interrupt.h>
10#include <linux/of_platform.h>
11#include <linux/of_irq.h>
12
13#include <asm/mach-ralink/ralink_regs.h>
14
15#define REG_ILL_ACC_ADDR	0x10
16#define REG_ILL_ACC_TYPE	0x14
17
18#define ILL_INT_STATUS		BIT(31)
19#define ILL_ACC_WRITE		BIT(30)
20#define ILL_ACC_LEN_M		0xff
21#define ILL_ACC_OFF_M		0xf
22#define ILL_ACC_OFF_S		16
23#define ILL_ACC_ID_M		0x7
24#define ILL_ACC_ID_S		8
25
26#define	DRV_NAME		"ill_acc"
27
28static const char * const ill_acc_ids[] = {
29	"cpu", "dma", "ppe", "pdma rx", "pdma tx", "pci/e", "wmac", "usb",
30};
31
32static irqreturn_t ill_acc_irq_handler(int irq, void *_priv)
33{
34	struct device *dev = (struct device *) _priv;
35	u32 addr = rt_memc_r32(REG_ILL_ACC_ADDR);
36	u32 type = rt_memc_r32(REG_ILL_ACC_TYPE);
37
38	dev_err(dev, "illegal %s access from %s - addr:0x%08x offset:%d len:%d\n",
39		(type & ILL_ACC_WRITE) ? ("write") : ("read"),
40		ill_acc_ids[(type >> ILL_ACC_ID_S) & ILL_ACC_ID_M],
41		addr, (type >> ILL_ACC_OFF_S) & ILL_ACC_OFF_M,
42		type & ILL_ACC_LEN_M);
43
44	rt_memc_w32(ILL_INT_STATUS, REG_ILL_ACC_TYPE);
45
46	return IRQ_HANDLED;
47}
48
49static int __init ill_acc_of_setup(void)
50{
51	struct platform_device *pdev;
52	struct device_node *np;
53	int irq;
54
55	/* somehow this driver breaks on RT5350 */
56	if (of_machine_is_compatible("ralink,rt5350-soc"))
57		return -EINVAL;
58
59	np = of_find_compatible_node(NULL, NULL, "ralink,rt3050-memc");
60	if (!np)
61		return -EINVAL;
62
63	pdev = of_find_device_by_node(np);
64	if (!pdev) {
65		pr_err("%s: failed to lookup pdev\n", np->name);
66		return -EINVAL;
67	}
68
69	irq = irq_of_parse_and_map(np, 0);
70	if (!irq) {
71		dev_err(&pdev->dev, "failed to get irq\n");
72		return -EINVAL;
73	}
74
75	if (request_irq(irq, ill_acc_irq_handler, 0, "ill_acc", &pdev->dev)) {
76		dev_err(&pdev->dev, "failed to request irq\n");
77		return -EINVAL;
78	}
79
80	rt_memc_w32(ILL_INT_STATUS, REG_ILL_ACC_TYPE);
81
82	dev_info(&pdev->dev, "irq registered\n");
83
84	return 0;
85}
86
87arch_initcall(ill_acc_of_setup);
88