xref: /openbmc/linux/arch/powerpc/sysdev/fsl_mpic_err.c (revision 03ab8e6297acd1bc0eedaa050e2a1635c576fd11)
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  #include <linux/irqdomain.h>
12  
13  #include <asm/io.h>
14  #include <asm/irq.h>
15  #include <asm/mpic.h>
16  
17  #include "mpic.h"
18  
19  #define MPIC_ERR_INT_BASE	0x3900
20  #define MPIC_ERR_INT_EISR	0x0000
21  #define MPIC_ERR_INT_EIMR	0x0010
22  
mpic_fsl_err_read(u32 __iomem * base,unsigned int err_reg)23  static inline u32 mpic_fsl_err_read(u32 __iomem *base, unsigned int err_reg)
24  {
25  	return in_be32(base + (err_reg >> 2));
26  }
27  
mpic_fsl_err_write(u32 __iomem * base,u32 value)28  static inline void mpic_fsl_err_write(u32 __iomem *base, u32 value)
29  {
30  	out_be32(base + (MPIC_ERR_INT_EIMR >> 2), value);
31  }
32  
fsl_mpic_mask_err(struct irq_data * d)33  static void fsl_mpic_mask_err(struct irq_data *d)
34  {
35  	u32 eimr;
36  	struct mpic *mpic = irq_data_get_irq_chip_data(d);
37  	unsigned int src = virq_to_hw(d->irq) - mpic->err_int_vecs[0];
38  
39  	eimr = mpic_fsl_err_read(mpic->err_regs, MPIC_ERR_INT_EIMR);
40  	eimr |= (1 << (31 - src));
41  	mpic_fsl_err_write(mpic->err_regs, eimr);
42  }
43  
fsl_mpic_unmask_err(struct irq_data * d)44  static void fsl_mpic_unmask_err(struct irq_data *d)
45  {
46  	u32 eimr;
47  	struct mpic *mpic = irq_data_get_irq_chip_data(d);
48  	unsigned int src = virq_to_hw(d->irq) - mpic->err_int_vecs[0];
49  
50  	eimr = mpic_fsl_err_read(mpic->err_regs, MPIC_ERR_INT_EIMR);
51  	eimr &= ~(1 << (31 - src));
52  	mpic_fsl_err_write(mpic->err_regs, eimr);
53  }
54  
55  static struct irq_chip fsl_mpic_err_chip = {
56  	.irq_disable	= fsl_mpic_mask_err,
57  	.irq_mask	= fsl_mpic_mask_err,
58  	.irq_unmask	= fsl_mpic_unmask_err,
59  };
60  
mpic_setup_error_int(struct mpic * mpic,int intvec)61  int __init mpic_setup_error_int(struct mpic *mpic, int intvec)
62  {
63  	int i;
64  
65  	mpic->err_regs = ioremap(mpic->paddr + MPIC_ERR_INT_BASE, 0x1000);
66  	if (!mpic->err_regs) {
67  		pr_err("could not map mpic error registers\n");
68  		return -ENOMEM;
69  	}
70  	mpic->hc_err = fsl_mpic_err_chip;
71  	mpic->hc_err.name = mpic->name;
72  	mpic->flags |= MPIC_FSL_HAS_EIMR;
73  	/* allocate interrupt vectors for error interrupts */
74  	for (i = MPIC_MAX_ERR - 1; i >= 0; i--)
75  		mpic->err_int_vecs[i] = intvec--;
76  
77  	return 0;
78  }
79  
mpic_map_error_int(struct mpic * mpic,unsigned int virq,irq_hw_number_t hw)80  int mpic_map_error_int(struct mpic *mpic, unsigned int virq, irq_hw_number_t  hw)
81  {
82  	if ((mpic->flags & MPIC_FSL_HAS_EIMR) &&
83  	    (hw >= mpic->err_int_vecs[0] &&
84  	     hw <= mpic->err_int_vecs[MPIC_MAX_ERR - 1])) {
85  		WARN_ON(mpic->flags & MPIC_SECONDARY);
86  
87  		pr_debug("mpic: mapping as Error Interrupt\n");
88  		irq_set_chip_data(virq, mpic);
89  		irq_set_chip_and_handler(virq, &mpic->hc_err,
90  					 handle_level_irq);
91  		return 1;
92  	}
93  
94  	return 0;
95  }
96  
fsl_error_int_handler(int irq,void * data)97  static irqreturn_t fsl_error_int_handler(int irq, void *data)
98  {
99  	struct mpic *mpic = (struct mpic *) data;
100  	u32 eisr, eimr;
101  	int errint;
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  		int ret;
111  		errint = __builtin_clz(eisr);
112  		ret = generic_handle_domain_irq(mpic->irqhost,
113  						mpic->err_int_vecs[errint]);
114  		if (WARN_ON(ret)) {
115  			eimr |=  1 << (31 - errint);
116  			mpic_fsl_err_write(mpic->err_regs, eimr);
117  		}
118  		eisr &= ~(1 << (31 - errint));
119  	}
120  
121  	return IRQ_HANDLED;
122  }
123  
mpic_err_int_init(struct mpic * mpic,irq_hw_number_t irqnum)124  void __init mpic_err_int_init(struct mpic *mpic, irq_hw_number_t irqnum)
125  {
126  	unsigned int virq;
127  	int ret;
128  
129  	virq = irq_create_mapping(mpic->irqhost, irqnum);
130  	if (!virq) {
131  		pr_err("Error interrupt setup failed\n");
132  		return;
133  	}
134  
135  	/* Mask all error interrupts */
136  	mpic_fsl_err_write(mpic->err_regs, ~0);
137  
138  	ret = request_irq(virq, fsl_error_int_handler, IRQF_NO_THREAD,
139  		    "mpic-error-int", mpic);
140  	if (ret)
141  		pr_err("Failed to register error interrupt handler\n");
142  }
143