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authorFlorian Fainelli <f.fainelli@gmail.com>2014-09-10 04:44:21 +0400
committerJason Cooper <jason@lakedaemon.net>2014-09-14 10:20:14 +0400
commita5042de2688d3e903799caf1196539c57555e3ed (patch)
tree045e86aadbf56a119c864c39774ac5bac9d395f8 /drivers/irqchip/irq-bcm7120-l2.c
parent7d1311b93e58ed55f3a31cc8f94c4b8fe988a2b9 (diff)
downloadlinux-a5042de2688d3e903799caf1196539c57555e3ed.tar.xz
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>
Diffstat (limited to 'drivers/irqchip/irq-bcm7120-l2.c')
-rw-r--r--drivers/irqchip/irq-bcm7120-l2.c219
1 files changed, 219 insertions, 0 deletions
diff --git a/drivers/irqchip/irq-bcm7120-l2.c b/drivers/irqchip/irq-bcm7120-l2.c
new file mode 100644
index 000000000000..b9f4fb808e49
--- /dev/null
+++ b/drivers/irqchip/irq-bcm7120-l2.c
@@ -0,0 +1,219 @@
+/*
+ * Broadcom BCM7120 style Level 2 interrupt controller driver
+ *
+ * Copyright (C) 2014 Broadcom Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/of.h>
+#include <linux/of_irq.h>
+#include <linux/of_address.h>
+#include <linux/of_platform.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/io.h>
+#include <linux/irqdomain.h>
+#include <linux/reboot.h>
+#include <linux/irqchip/chained_irq.h>
+
+#include "irqchip.h"
+
+#include <asm/mach/irq.h>
+
+/* Register offset in the L2 interrupt controller */
+#define IRQEN 0x00
+#define IRQSTAT 0x04
+
+struct bcm7120_l2_intc_data {
+ void __iomem *base;
+ struct irq_domain *domain;
+ bool can_wake;
+ u32 irq_fwd_mask;
+ u32 irq_map_mask;
+ u32 saved_mask;
+};
+
+static void bcm7120_l2_intc_irq_handle(unsigned int irq, struct irq_desc *desc)
+{
+ struct bcm7120_l2_intc_data *b = irq_desc_get_handler_data(desc);
+ struct irq_chip *chip = irq_desc_get_chip(desc);
+ u32 status;
+
+ chained_irq_enter(chip, desc);
+
+ status = __raw_readl(b->base + IRQSTAT);
+
+ if (status == 0) {
+ do_bad_IRQ(irq, desc);
+ goto out;
+ }
+
+ do {
+ irq = ffs(status) - 1;
+ status &= ~(1 << irq);
+ generic_handle_irq(irq_find_mapping(b->domain, irq));
+ } while (status);
+
+out:
+ chained_irq_exit(chip, desc);
+}
+
+static void bcm7120_l2_intc_suspend(struct irq_data *d)
+{
+ struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
+ struct bcm7120_l2_intc_data *b = gc->private;
+ u32 reg;
+
+ irq_gc_lock(gc);
+ /* Save the current mask and the interrupt forward mask */
+ b->saved_mask = __raw_readl(b->base) | b->irq_fwd_mask;
+ if (b->can_wake) {
+ reg = b->saved_mask | gc->wake_active;
+ __raw_writel(reg, b->base);
+ }
+ irq_gc_unlock(gc);
+}
+
+static void bcm7120_l2_intc_resume(struct irq_data *d)
+{
+ struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
+ struct bcm7120_l2_intc_data *b = gc->private;
+
+ /* Restore the saved mask */
+ irq_gc_lock(gc);
+ __raw_writel(b->saved_mask, b->base);
+ irq_gc_unlock(gc);
+}
+
+static int bcm7120_l2_intc_init_one(struct device_node *dn,
+ struct bcm7120_l2_intc_data *data,
+ int irq, const __be32 *map_mask)
+{
+ int parent_irq;
+
+ parent_irq = irq_of_parse_and_map(dn, irq);
+ if (parent_irq < 0) {
+ pr_err("failed to map interrupt %d\n", irq);
+ return parent_irq;
+ }
+
+ data->irq_map_mask |= be32_to_cpup(map_mask + irq);
+
+ irq_set_handler_data(parent_irq, data);
+ irq_set_chained_handler(parent_irq, bcm7120_l2_intc_irq_handle);
+
+ return 0;
+}
+
+int __init bcm7120_l2_intc_of_init(struct device_node *dn,
+ struct device_node *parent)
+{
+ unsigned int clr = IRQ_NOREQUEST | IRQ_NOPROBE | IRQ_NOAUTOEN;
+ struct bcm7120_l2_intc_data *data;
+ struct irq_chip_generic *gc;
+ struct irq_chip_type *ct;
+ const __be32 *map_mask;
+ int num_parent_irqs;
+ int ret = 0, len, irq;
+
+ data = kzalloc(sizeof(*data), GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ data->base = of_iomap(dn, 0);
+ if (!data->base) {
+ pr_err("failed to remap intc L2 registers\n");
+ ret = -ENOMEM;
+ goto out_free;
+ }
+
+ if (of_property_read_u32(dn, "brcm,int-fwd-mask", &data->irq_fwd_mask))
+ data->irq_fwd_mask = 0;
+
+ /* Enable all interrupt specified in the interrupt forward mask and have
+ * the other disabled
+ */
+ __raw_writel(data->irq_fwd_mask, data->base + IRQEN);
+
+ num_parent_irqs = of_irq_count(dn);
+ if (num_parent_irqs <= 0) {
+ pr_err("invalid number of parent interrupts\n");
+ ret = -ENOMEM;
+ goto out_unmap;
+ }
+
+ map_mask = of_get_property(dn, "brcm,int-map-mask", &len);
+ if (!map_mask || (len != (sizeof(*map_mask) * num_parent_irqs))) {
+ pr_err("invalid brcm,int-map-mask property\n");
+ ret = -EINVAL;
+ goto out_unmap;
+ }
+
+ for (irq = 0; irq < num_parent_irqs; irq++) {
+ ret = bcm7120_l2_intc_init_one(dn, data, irq, map_mask);
+ if (ret)
+ goto out_unmap;
+ }
+
+ data->domain = irq_domain_add_linear(dn, 32,
+ &irq_generic_chip_ops, NULL);
+ if (!data->domain) {
+ ret = -ENOMEM;
+ goto out_unmap;
+ }
+
+ ret = irq_alloc_domain_generic_chips(data->domain, 32, 1,
+ dn->full_name, handle_level_irq, clr, 0,
+ IRQ_GC_INIT_MASK_CACHE);
+ if (ret) {
+ pr_err("failed to allocate generic irq chip\n");
+ goto out_free_domain;
+ }
+
+ gc = irq_get_domain_generic_chip(data->domain, 0);
+ gc->unused = 0xfffffff & ~data->irq_map_mask;
+ gc->reg_base = data->base;
+ gc->private = data;
+ ct = gc->chip_types;
+
+ ct->regs.mask = IRQEN;
+ ct->chip.irq_mask = irq_gc_mask_clr_bit;
+ ct->chip.irq_unmask = irq_gc_mask_set_bit;
+ ct->chip.irq_ack = irq_gc_noop;
+ ct->chip.irq_suspend = bcm7120_l2_intc_suspend;
+ ct->chip.irq_resume = bcm7120_l2_intc_resume;
+
+ if (of_property_read_bool(dn, "brcm,irq-can-wake")) {
+ data->can_wake = true;
+ /* This IRQ chip can wake the system, set all relevant child
+ * interupts in wake_enabled mask
+ */
+ gc->wake_enabled = 0xffffffff;
+ gc->wake_enabled &= ~gc->unused;
+ ct->chip.irq_set_wake = irq_gc_set_wake;
+ }
+
+ pr_info("registered BCM7120 L2 intc (mem: 0x%p, parent IRQ(s): %d)\n",
+ data->base, num_parent_irqs);
+
+ return 0;
+
+out_free_domain:
+ irq_domain_remove(data->domain);
+out_unmap:
+ iounmap(data->base);
+out_free:
+ kfree(data);
+ return ret;
+}
+IRQCHIP_DECLARE(brcmstb_l2_intc, "brcm,bcm7120-l2-intc",
+ bcm7120_l2_intc_of_init);