1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 *
4 * Copyright (C) 2013 John Crispin <john@phrozen.org>
5 */
6
7#include <linux/interrupt.h>
8#include <linux/of_platform.h>
9#include <linux/of_irq.h>
10
11#include <asm/mach-ralink/ralink_regs.h>
12
13#define REG_ILL_ACC_ADDR	0x10
14#define REG_ILL_ACC_TYPE	0x14
15
16#define ILL_INT_STATUS		BIT(31)
17#define ILL_ACC_WRITE		BIT(30)
18#define ILL_ACC_LEN_M		0xff
19#define ILL_ACC_OFF_M		0xf
20#define ILL_ACC_OFF_S		16
21#define ILL_ACC_ID_M		0x7
22#define ILL_ACC_ID_S		8
23
24#define	DRV_NAME		"ill_acc"
25
26static const char * const ill_acc_ids[] = {
27	"cpu", "dma", "ppe", "pdma rx", "pdma tx", "pci/e", "wmac", "usb",
28};
29
30static irqreturn_t ill_acc_irq_handler(int irq, void *_priv)
31{
32	struct device *dev = (struct device *) _priv;
33	u32 addr = rt_memc_r32(REG_ILL_ACC_ADDR);
34	u32 type = rt_memc_r32(REG_ILL_ACC_TYPE);
35
36	dev_err(dev, "illegal %s access from %s - addr:0x%08x offset:%d len:%d\n",
37		(type & ILL_ACC_WRITE) ? ("write") : ("read"),
38		ill_acc_ids[(type >> ILL_ACC_ID_S) & ILL_ACC_ID_M],
39		addr, (type >> ILL_ACC_OFF_S) & ILL_ACC_OFF_M,
40		type & ILL_ACC_LEN_M);
41
42	rt_memc_w32(ILL_INT_STATUS, REG_ILL_ACC_TYPE);
43
44	return IRQ_HANDLED;
45}
46
47static int __init ill_acc_of_setup(void)
48{
49	struct platform_device *pdev;
50	struct device_node *np;
51	int irq;
52
53	/* somehow this driver breaks on RT5350 */
54	if (of_machine_is_compatible("ralink,rt5350-soc"))
55		return -EINVAL;
56
57	np = of_find_compatible_node(NULL, NULL, "ralink,rt3050-memc");
58	if (!np)
59		return -EINVAL;
60
61	pdev = of_find_device_by_node(np);
62	if (!pdev) {
63		pr_err("%pOFn: failed to lookup pdev\n", np);
64		of_node_put(np);
65		return -EINVAL;
66	}
67
68	irq = irq_of_parse_and_map(np, 0);
69	if (!irq) {
70		dev_err(&pdev->dev, "failed to get irq\n");
71		put_device(&pdev->dev);
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		put_device(&pdev->dev);
78		return -EINVAL;
79	}
80
81	rt_memc_w32(ILL_INT_STATUS, REG_ILL_ACC_TYPE);
82
83	dev_info(&pdev->dev, "irq registered\n");
84
85	return 0;
86}
87
88arch_initcall(ill_acc_of_setup);
89