1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (C) 2012 Freescale Semiconductor, Inc.
4 *
5 * Author: Varun Sethi <varun.sethi@freescale.com>
6 */
7
8 #include <linux/irq.h>
9 #include <linux/smp.h>
10 #include <linux/interrupt.h>
11
12 #include <asm/io.h>
13 #include <asm/irq.h>
14 #include <asm/mpic.h>
15
16 #include "mpic.h"
17
18 #define MPIC_ERR_INT_BASE 0x3900
19 #define MPIC_ERR_INT_EISR 0x0000
20 #define MPIC_ERR_INT_EIMR 0x0010
21
mpic_fsl_err_read(u32 __iomem * base,unsigned int err_reg)22 static inline u32 mpic_fsl_err_read(u32 __iomem *base, unsigned int err_reg)
23 {
24 return in_be32(base + (err_reg >> 2));
25 }
26
mpic_fsl_err_write(u32 __iomem * base,u32 value)27 static inline void mpic_fsl_err_write(u32 __iomem *base, u32 value)
28 {
29 out_be32(base + (MPIC_ERR_INT_EIMR >> 2), value);
30 }
31
fsl_mpic_mask_err(struct irq_data * d)32 static void fsl_mpic_mask_err(struct irq_data *d)
33 {
34 u32 eimr;
35 struct mpic *mpic = irq_data_get_irq_chip_data(d);
36 unsigned int src = virq_to_hw(d->irq) - mpic->err_int_vecs[0];
37
38 eimr = mpic_fsl_err_read(mpic->err_regs, MPIC_ERR_INT_EIMR);
39 eimr |= (1 << (31 - src));
40 mpic_fsl_err_write(mpic->err_regs, eimr);
41 }
42
fsl_mpic_unmask_err(struct irq_data * d)43 static void fsl_mpic_unmask_err(struct irq_data *d)
44 {
45 u32 eimr;
46 struct mpic *mpic = irq_data_get_irq_chip_data(d);
47 unsigned int src = virq_to_hw(d->irq) - mpic->err_int_vecs[0];
48
49 eimr = mpic_fsl_err_read(mpic->err_regs, MPIC_ERR_INT_EIMR);
50 eimr &= ~(1 << (31 - src));
51 mpic_fsl_err_write(mpic->err_regs, eimr);
52 }
53
54 static struct irq_chip fsl_mpic_err_chip = {
55 .irq_disable = fsl_mpic_mask_err,
56 .irq_mask = fsl_mpic_mask_err,
57 .irq_unmask = fsl_mpic_unmask_err,
58 };
59
mpic_setup_error_int(struct mpic * mpic,int intvec)60 int mpic_setup_error_int(struct mpic *mpic, int intvec)
61 {
62 int i;
63
64 mpic->err_regs = ioremap(mpic->paddr + MPIC_ERR_INT_BASE, 0x1000);
65 if (!mpic->err_regs) {
66 pr_err("could not map mpic error registers\n");
67 return -ENOMEM;
68 }
69 mpic->hc_err = fsl_mpic_err_chip;
70 mpic->hc_err.name = mpic->name;
71 mpic->flags |= MPIC_FSL_HAS_EIMR;
72 /* allocate interrupt vectors for error interrupts */
73 for (i = MPIC_MAX_ERR - 1; i >= 0; i--)
74 mpic->err_int_vecs[i] = intvec--;
75
76 return 0;
77 }
78
mpic_map_error_int(struct mpic * mpic,unsigned int virq,irq_hw_number_t hw)79 int mpic_map_error_int(struct mpic *mpic, unsigned int virq, irq_hw_number_t hw)
80 {
81 if ((mpic->flags & MPIC_FSL_HAS_EIMR) &&
82 (hw >= mpic->err_int_vecs[0] &&
83 hw <= mpic->err_int_vecs[MPIC_MAX_ERR - 1])) {
84 WARN_ON(mpic->flags & MPIC_SECONDARY);
85
86 pr_debug("mpic: mapping as Error Interrupt\n");
87 irq_set_chip_data(virq, mpic);
88 irq_set_chip_and_handler(virq, &mpic->hc_err,
89 handle_level_irq);
90 return 1;
91 }
92
93 return 0;
94 }
95
fsl_error_int_handler(int irq,void * data)96 static irqreturn_t fsl_error_int_handler(int irq, void *data)
97 {
98 struct mpic *mpic = (struct mpic *) data;
99 u32 eisr, eimr;
100 int errint;
101 unsigned int cascade_irq;
102
103 eisr = mpic_fsl_err_read(mpic->err_regs, MPIC_ERR_INT_EISR);
104 eimr = mpic_fsl_err_read(mpic->err_regs, MPIC_ERR_INT_EIMR);
105
106 if (!(eisr & ~eimr))
107 return IRQ_NONE;
108
109 while (eisr) {
110 errint = __builtin_clz(eisr);
111 cascade_irq = irq_linear_revmap(mpic->irqhost,
112 mpic->err_int_vecs[errint]);
113 WARN_ON(!cascade_irq);
114 if (cascade_irq) {
115 generic_handle_irq(cascade_irq);
116 } else {
117 eimr |= 1 << (31 - errint);
118 mpic_fsl_err_write(mpic->err_regs, eimr);
119 }
120 eisr &= ~(1 << (31 - errint));
121 }
122
123 return IRQ_HANDLED;
124 }
125
mpic_err_int_init(struct mpic * mpic,irq_hw_number_t irqnum)126 void mpic_err_int_init(struct mpic *mpic, irq_hw_number_t irqnum)
127 {
128 unsigned int virq;
129 int ret;
130
131 virq = irq_create_mapping(mpic->irqhost, irqnum);
132 if (!virq) {
133 pr_err("Error interrupt setup failed\n");
134 return;
135 }
136
137 /* Mask all error interrupts */
138 mpic_fsl_err_write(mpic->err_regs, ~0);
139
140 ret = request_irq(virq, fsl_error_int_handler, IRQF_NO_THREAD,
141 "mpic-error-int", mpic);
142 if (ret)
143 pr_err("Failed to register error interrupt handler\n");
144 }
145