Commit a5042de2688d3e903799caf1196539c57555e3ed

Authored by Florian Fainelli
Committed by Jason Cooper
1 parent 7d1311b93e

irqchip: bcm7120-l2: Add Broadcom BCM7120-style Level 2 interrupt controller

This patch adds support for the Level-2 interrupt controller
hardware found in Broadcom Set Top Box System-on-a-Chip devices. This
interrupt controller is implemented using a single enable register.

This interrupt controller is always present on the platforms supported
by the irq-brcmstb-l2 driver, hence the reason why both are compiled
using the same Kconfig symbol.

[jac] removed the following warning:
  drivers/irqchip/irq-bcm7120-l2.c: In function 'bcm7120_l2_intc_irq_handle':
  drivers/irqchip/irq-bcm7120-l2.c:49:27: warning: unused variable 'gc' [-Wunused-variable]

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Link: https://lkml.kernel.org/r/1410309862-27784-2-git-send-email-f.fainelli@gmail.com
Signed-off-by: Jason Cooper <jason@lakedaemon.net>

Showing 2 changed files with 221 additions and 1 deletions Side-by-side Diff

drivers/irqchip/Makefile
... ... @@ -33,5 +33,6 @@
33 33 obj-$(CONFIG_XTENSA) += irq-xtensa-pic.o
34 34 obj-$(CONFIG_XTENSA_MX) += irq-xtensa-mx.o
35 35 obj-$(CONFIG_IRQ_CROSSBAR) += irq-crossbar.o
36   -obj-$(CONFIG_BRCMSTB_L2_IRQ) += irq-brcmstb-l2.o
  36 +obj-$(CONFIG_BRCMSTB_L2_IRQ) += irq-brcmstb-l2.o \
  37 + irq-bcm7120-l2.o
drivers/irqchip/irq-bcm7120-l2.c
  1 +/*
  2 + * Broadcom BCM7120 style Level 2 interrupt controller driver
  3 + *
  4 + * Copyright (C) 2014 Broadcom Corporation
  5 + *
  6 + * This program is free software; you can redistribute it and/or modify
  7 + * it under the terms of the GNU General Public License version 2 as
  8 + * published by the Free Software Foundation.
  9 + */
  10 +
  11 +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  12 +
  13 +#include <linux/init.h>
  14 +#include <linux/slab.h>
  15 +#include <linux/module.h>
  16 +#include <linux/platform_device.h>
  17 +#include <linux/of.h>
  18 +#include <linux/of_irq.h>
  19 +#include <linux/of_address.h>
  20 +#include <linux/of_platform.h>
  21 +#include <linux/interrupt.h>
  22 +#include <linux/irq.h>
  23 +#include <linux/io.h>
  24 +#include <linux/irqdomain.h>
  25 +#include <linux/reboot.h>
  26 +#include <linux/irqchip/chained_irq.h>
  27 +
  28 +#include "irqchip.h"
  29 +
  30 +#include <asm/mach/irq.h>
  31 +
  32 +/* Register offset in the L2 interrupt controller */
  33 +#define IRQEN 0x00
  34 +#define IRQSTAT 0x04
  35 +
  36 +struct bcm7120_l2_intc_data {
  37 + void __iomem *base;
  38 + struct irq_domain *domain;
  39 + bool can_wake;
  40 + u32 irq_fwd_mask;
  41 + u32 irq_map_mask;
  42 + u32 saved_mask;
  43 +};
  44 +
  45 +static void bcm7120_l2_intc_irq_handle(unsigned int irq, struct irq_desc *desc)
  46 +{
  47 + struct bcm7120_l2_intc_data *b = irq_desc_get_handler_data(desc);
  48 + struct irq_chip *chip = irq_desc_get_chip(desc);
  49 + u32 status;
  50 +
  51 + chained_irq_enter(chip, desc);
  52 +
  53 + status = __raw_readl(b->base + IRQSTAT);
  54 +
  55 + if (status == 0) {
  56 + do_bad_IRQ(irq, desc);
  57 + goto out;
  58 + }
  59 +
  60 + do {
  61 + irq = ffs(status) - 1;
  62 + status &= ~(1 << irq);
  63 + generic_handle_irq(irq_find_mapping(b->domain, irq));
  64 + } while (status);
  65 +
  66 +out:
  67 + chained_irq_exit(chip, desc);
  68 +}
  69 +
  70 +static void bcm7120_l2_intc_suspend(struct irq_data *d)
  71 +{
  72 + struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
  73 + struct bcm7120_l2_intc_data *b = gc->private;
  74 + u32 reg;
  75 +
  76 + irq_gc_lock(gc);
  77 + /* Save the current mask and the interrupt forward mask */
  78 + b->saved_mask = __raw_readl(b->base) | b->irq_fwd_mask;
  79 + if (b->can_wake) {
  80 + reg = b->saved_mask | gc->wake_active;
  81 + __raw_writel(reg, b->base);
  82 + }
  83 + irq_gc_unlock(gc);
  84 +}
  85 +
  86 +static void bcm7120_l2_intc_resume(struct irq_data *d)
  87 +{
  88 + struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
  89 + struct bcm7120_l2_intc_data *b = gc->private;
  90 +
  91 + /* Restore the saved mask */
  92 + irq_gc_lock(gc);
  93 + __raw_writel(b->saved_mask, b->base);
  94 + irq_gc_unlock(gc);
  95 +}
  96 +
  97 +static int bcm7120_l2_intc_init_one(struct device_node *dn,
  98 + struct bcm7120_l2_intc_data *data,
  99 + int irq, const __be32 *map_mask)
  100 +{
  101 + int parent_irq;
  102 +
  103 + parent_irq = irq_of_parse_and_map(dn, irq);
  104 + if (parent_irq < 0) {
  105 + pr_err("failed to map interrupt %d\n", irq);
  106 + return parent_irq;
  107 + }
  108 +
  109 + data->irq_map_mask |= be32_to_cpup(map_mask + irq);
  110 +
  111 + irq_set_handler_data(parent_irq, data);
  112 + irq_set_chained_handler(parent_irq, bcm7120_l2_intc_irq_handle);
  113 +
  114 + return 0;
  115 +}
  116 +
  117 +int __init bcm7120_l2_intc_of_init(struct device_node *dn,
  118 + struct device_node *parent)
  119 +{
  120 + unsigned int clr = IRQ_NOREQUEST | IRQ_NOPROBE | IRQ_NOAUTOEN;
  121 + struct bcm7120_l2_intc_data *data;
  122 + struct irq_chip_generic *gc;
  123 + struct irq_chip_type *ct;
  124 + const __be32 *map_mask;
  125 + int num_parent_irqs;
  126 + int ret = 0, len, irq;
  127 +
  128 + data = kzalloc(sizeof(*data), GFP_KERNEL);
  129 + if (!data)
  130 + return -ENOMEM;
  131 +
  132 + data->base = of_iomap(dn, 0);
  133 + if (!data->base) {
  134 + pr_err("failed to remap intc L2 registers\n");
  135 + ret = -ENOMEM;
  136 + goto out_free;
  137 + }
  138 +
  139 + if (of_property_read_u32(dn, "brcm,int-fwd-mask", &data->irq_fwd_mask))
  140 + data->irq_fwd_mask = 0;
  141 +
  142 + /* Enable all interrupt specified in the interrupt forward mask and have
  143 + * the other disabled
  144 + */
  145 + __raw_writel(data->irq_fwd_mask, data->base + IRQEN);
  146 +
  147 + num_parent_irqs = of_irq_count(dn);
  148 + if (num_parent_irqs <= 0) {
  149 + pr_err("invalid number of parent interrupts\n");
  150 + ret = -ENOMEM;
  151 + goto out_unmap;
  152 + }
  153 +
  154 + map_mask = of_get_property(dn, "brcm,int-map-mask", &len);
  155 + if (!map_mask || (len != (sizeof(*map_mask) * num_parent_irqs))) {
  156 + pr_err("invalid brcm,int-map-mask property\n");
  157 + ret = -EINVAL;
  158 + goto out_unmap;
  159 + }
  160 +
  161 + for (irq = 0; irq < num_parent_irqs; irq++) {
  162 + ret = bcm7120_l2_intc_init_one(dn, data, irq, map_mask);
  163 + if (ret)
  164 + goto out_unmap;
  165 + }
  166 +
  167 + data->domain = irq_domain_add_linear(dn, 32,
  168 + &irq_generic_chip_ops, NULL);
  169 + if (!data->domain) {
  170 + ret = -ENOMEM;
  171 + goto out_unmap;
  172 + }
  173 +
  174 + ret = irq_alloc_domain_generic_chips(data->domain, 32, 1,
  175 + dn->full_name, handle_level_irq, clr, 0,
  176 + IRQ_GC_INIT_MASK_CACHE);
  177 + if (ret) {
  178 + pr_err("failed to allocate generic irq chip\n");
  179 + goto out_free_domain;
  180 + }
  181 +
  182 + gc = irq_get_domain_generic_chip(data->domain, 0);
  183 + gc->unused = 0xfffffff & ~data->irq_map_mask;
  184 + gc->reg_base = data->base;
  185 + gc->private = data;
  186 + ct = gc->chip_types;
  187 +
  188 + ct->regs.mask = IRQEN;
  189 + ct->chip.irq_mask = irq_gc_mask_clr_bit;
  190 + ct->chip.irq_unmask = irq_gc_mask_set_bit;
  191 + ct->chip.irq_ack = irq_gc_noop;
  192 + ct->chip.irq_suspend = bcm7120_l2_intc_suspend;
  193 + ct->chip.irq_resume = bcm7120_l2_intc_resume;
  194 +
  195 + if (of_property_read_bool(dn, "brcm,irq-can-wake")) {
  196 + data->can_wake = true;
  197 + /* This IRQ chip can wake the system, set all relevant child
  198 + * interupts in wake_enabled mask
  199 + */
  200 + gc->wake_enabled = 0xffffffff;
  201 + gc->wake_enabled &= ~gc->unused;
  202 + ct->chip.irq_set_wake = irq_gc_set_wake;
  203 + }
  204 +
  205 + pr_info("registered BCM7120 L2 intc (mem: 0x%p, parent IRQ(s): %d)\n",
  206 + data->base, num_parent_irqs);
  207 +
  208 + return 0;
  209 +
  210 +out_free_domain:
  211 + irq_domain_remove(data->domain);
  212 +out_unmap:
  213 + iounmap(data->base);
  214 +out_free:
  215 + kfree(data);
  216 + return ret;
  217 +}
  218 +IRQCHIP_DECLARE(brcmstb_l2_intc, "brcm,bcm7120-l2-intc",
  219 + bcm7120_l2_intc_of_init);