blob: b83f32562a374755c468696793fdf9e05a6223e5 [file] [log] [blame]
Varun Sethi0a408162012-08-08 09:36:09 +05301/*
2 * Copyright (C) 2012 Freescale Semiconductor, Inc.
3 *
4 * Author: Varun Sethi <varun.sethi@freescale.com>
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; version 2 of the
9 * License.
10 *
11 */
12
13#include <linux/irq.h>
14#include <linux/smp.h>
15#include <linux/interrupt.h>
16
17#include <asm/io.h>
18#include <asm/irq.h>
19#include <asm/mpic.h>
20
21#include "mpic.h"
22
23#define MPIC_ERR_INT_BASE 0x3900
24#define MPIC_ERR_INT_EISR 0x0000
25#define MPIC_ERR_INT_EIMR 0x0010
26
27static inline u32 mpic_fsl_err_read(u32 __iomem *base, unsigned int err_reg)
28{
29 return in_be32(base + (err_reg >> 2));
30}
31
32static inline void mpic_fsl_err_write(u32 __iomem *base, u32 value)
33{
34 out_be32(base + (MPIC_ERR_INT_EIMR >> 2), value);
35}
36
37static void fsl_mpic_mask_err(struct irq_data *d)
38{
39 u32 eimr;
40 struct mpic *mpic = irq_data_get_irq_chip_data(d);
41 unsigned int src = virq_to_hw(d->irq) - mpic->err_int_vecs[0];
42
43 eimr = mpic_fsl_err_read(mpic->err_regs, MPIC_ERR_INT_EIMR);
44 eimr |= (1 << (31 - src));
45 mpic_fsl_err_write(mpic->err_regs, eimr);
46}
47
48static void fsl_mpic_unmask_err(struct irq_data *d)
49{
50 u32 eimr;
51 struct mpic *mpic = irq_data_get_irq_chip_data(d);
52 unsigned int src = virq_to_hw(d->irq) - mpic->err_int_vecs[0];
53
54 eimr = mpic_fsl_err_read(mpic->err_regs, MPIC_ERR_INT_EIMR);
55 eimr &= ~(1 << (31 - src));
56 mpic_fsl_err_write(mpic->err_regs, eimr);
57}
58
59static struct irq_chip fsl_mpic_err_chip = {
60 .irq_disable = fsl_mpic_mask_err,
61 .irq_mask = fsl_mpic_mask_err,
62 .irq_unmask = fsl_mpic_unmask_err,
63};
64
65int mpic_setup_error_int(struct mpic *mpic, int intvec)
66{
67 int i;
68
69 mpic->err_regs = ioremap(mpic->paddr + MPIC_ERR_INT_BASE, 0x1000);
70 if (!mpic->err_regs) {
71 pr_err("could not map mpic error registers\n");
72 return -ENOMEM;
73 }
74 mpic->hc_err = fsl_mpic_err_chip;
75 mpic->hc_err.name = mpic->name;
76 mpic->flags |= MPIC_FSL_HAS_EIMR;
77 /* allocate interrupt vectors for error interrupts */
78 for (i = MPIC_MAX_ERR - 1; i >= 0; i--)
79 mpic->err_int_vecs[i] = --intvec;
80
81 return 0;
82}
83
84int mpic_map_error_int(struct mpic *mpic, unsigned int virq, irq_hw_number_t hw)
85{
86 if ((mpic->flags & MPIC_FSL_HAS_EIMR) &&
87 (hw >= mpic->err_int_vecs[0] &&
88 hw <= mpic->err_int_vecs[MPIC_MAX_ERR - 1])) {
89 WARN_ON(mpic->flags & MPIC_SECONDARY);
90
91 pr_debug("mpic: mapping as Error Interrupt\n");
92 irq_set_chip_data(virq, mpic);
93 irq_set_chip_and_handler(virq, &mpic->hc_err,
94 handle_level_irq);
95 return 1;
96 }
97
98 return 0;
99}
100
101static irqreturn_t fsl_error_int_handler(int irq, void *data)
102{
103 struct mpic *mpic = (struct mpic *) data;
104 u32 eisr, eimr;
105 int errint;
106 unsigned int cascade_irq;
107
108 eisr = mpic_fsl_err_read(mpic->err_regs, MPIC_ERR_INT_EISR);
109 eimr = mpic_fsl_err_read(mpic->err_regs, MPIC_ERR_INT_EIMR);
110
111 if (!(eisr & ~eimr))
112 return IRQ_NONE;
113
114 while (eisr) {
115 errint = __builtin_clz(eisr);
116 cascade_irq = irq_linear_revmap(mpic->irqhost,
117 mpic->err_int_vecs[errint]);
118 WARN_ON(cascade_irq == NO_IRQ);
119 if (cascade_irq != NO_IRQ) {
120 generic_handle_irq(cascade_irq);
121 } else {
122 eimr |= 1 << (31 - errint);
123 mpic_fsl_err_write(mpic->err_regs, eimr);
124 }
125 eisr &= ~(1 << (31 - errint));
126 }
127
128 return IRQ_HANDLED;
129}
130
131void mpic_err_int_init(struct mpic *mpic, irq_hw_number_t irqnum)
132{
133 unsigned int virq;
134 int ret;
135
136 virq = irq_create_mapping(mpic->irqhost, irqnum);
137 if (virq == NO_IRQ) {
138 pr_err("Error interrupt setup failed\n");
139 return;
140 }
141
142 /* Mask all error interrupts */
143 mpic_fsl_err_write(mpic->err_regs, ~0);
144
145 ret = request_irq(virq, fsl_error_int_handler, IRQF_NO_THREAD,
146 "mpic-error-int", mpic);
147 if (ret)
148 pr_err("Failed to register error interrupt handler\n");
149}