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authorKevin Cernekee <cernekee@gmail.com>2014-12-25 09:49:06 -0800
committerRalf Baechle <ralf@linux-mips.org>2015-04-01 17:21:37 +0200
commit5f7f0317ed28b86bdae9baf65bb72d405b6f79ee (patch)
tree20b8cdaf9b909afd426e76d8b6d2a2b9a9fa6b35 /drivers/irqchip
parent7b7230e70e9eda75356cf15c450b65b77924486f (diff)
downloadlinux-next-5f7f0317ed28b86bdae9baf65bb72d405b6f79ee.tar.gz
IRQCHIP: Add new driver for BCM7038-style level 1 interrupt controllers
This is the main peripheral IRQ controller on the BCM7xxx MIPS chips; it has the following characteristics: - 64 to 160+ level IRQs - Atomic set/clear registers - Reasonably predictable register layout (N status words, then N mask status words, then N mask set words, then N mask clear words) - SMP affinity supported on most systems - Typically connected to MIPS IRQ 2,3,2,3 on CPUs 0,1,2,3 This driver registers one IRQ domain and one IRQ chip to cover all instances of the block. Up to 4 instances of the block may appear, as it supports 4-way IRQ affinity on BCM7435. The same block exists on the ARM BCM7xxx chips, but typically the ARM GIC is used instead. So this driver is primarily intended for MIPS STB chips. Signed-off-by: Kevin Cernekee <cernekee@gmail.com> Cc: f.fainelli@gmail.com Cc: jaedon.shin@gmail.com Cc: abrestic@chromium.org Cc: tglx@linutronix.de Cc: jason@lakedaemon.net Cc: jogo@openwrt.org Cc: arnd@arndb.de Cc: computersforpeace@gmail.com Cc: linux-mips@linux-mips.org Cc: devicetree@vger.kernel.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/8844/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Diffstat (limited to 'drivers/irqchip')
-rw-r--r--drivers/irqchip/Kconfig5
-rw-r--r--drivers/irqchip/Makefile1
-rw-r--r--drivers/irqchip/irq-bcm7038-l1.c335
3 files changed, 341 insertions, 0 deletions
diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig
index cc79d2a5a8c2..241a5b2dd6a1 100644
--- a/drivers/irqchip/Kconfig
+++ b/drivers/irqchip/Kconfig
@@ -60,6 +60,11 @@ config ATMEL_AIC5_IRQ
select MULTI_IRQ_HANDLER
select SPARSE_IRQ
+config BCM7038_L1_IRQ
+ bool
+ select GENERIC_IRQ_CHIP
+ select IRQ_DOMAIN
+
config BCM7120_L2_IRQ
bool
select GENERIC_IRQ_CHIP
diff --git a/drivers/irqchip/Makefile b/drivers/irqchip/Makefile
index 42965d2476bb..89e45613de76 100644
--- a/drivers/irqchip/Makefile
+++ b/drivers/irqchip/Makefile
@@ -37,6 +37,7 @@ obj-$(CONFIG_TB10X_IRQC) += irq-tb10x.o
obj-$(CONFIG_XTENSA) += irq-xtensa-pic.o
obj-$(CONFIG_XTENSA_MX) += irq-xtensa-mx.o
obj-$(CONFIG_IRQ_CROSSBAR) += irq-crossbar.o
+obj-$(CONFIG_BCM7038_L1_IRQ) += irq-bcm7038-l1.o
obj-$(CONFIG_BCM7120_L2_IRQ) += irq-bcm7120-l2.o
obj-$(CONFIG_BRCMSTB_L2_IRQ) += irq-brcmstb-l2.o
obj-$(CONFIG_KEYSTONE_IRQ) += irq-keystone.o
diff --git a/drivers/irqchip/irq-bcm7038-l1.c b/drivers/irqchip/irq-bcm7038-l1.c
new file mode 100644
index 000000000000..d3b8c8be15f6
--- /dev/null
+++ b/drivers/irqchip/irq-bcm7038-l1.c
@@ -0,0 +1,335 @@
+/*
+ * Broadcom BCM7038 style Level 1 interrupt controller driver
+ *
+ * Copyright (C) 2014 Broadcom Corporation
+ * Author: Kevin Cernekee
+ *
+ * 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/bitops.h>
+#include <linux/kconfig.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/ioport.h>
+#include <linux/irq.h>
+#include <linux/irqdomain.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_irq.h>
+#include <linux/of_address.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/smp.h>
+#include <linux/types.h>
+#include <linux/irqchip/chained_irq.h>
+
+#include "irqchip.h"
+
+#define IRQS_PER_WORD 32
+#define REG_BYTES_PER_IRQ_WORD (sizeof(u32) * 4)
+#define MAX_WORDS 8
+
+struct bcm7038_l1_cpu;
+
+struct bcm7038_l1_chip {
+ raw_spinlock_t lock;
+ unsigned int n_words;
+ struct irq_domain *domain;
+ struct bcm7038_l1_cpu *cpus[NR_CPUS];
+ u8 affinity[MAX_WORDS * IRQS_PER_WORD];
+};
+
+struct bcm7038_l1_cpu {
+ void __iomem *map_base;
+ u32 mask_cache[0];
+};
+
+/*
+ * STATUS/MASK_STATUS/MASK_SET/MASK_CLEAR are packed one right after another:
+ *
+ * 7038:
+ * 0x1000_1400: W0_STATUS
+ * 0x1000_1404: W1_STATUS
+ * 0x1000_1408: W0_MASK_STATUS
+ * 0x1000_140c: W1_MASK_STATUS
+ * 0x1000_1410: W0_MASK_SET
+ * 0x1000_1414: W1_MASK_SET
+ * 0x1000_1418: W0_MASK_CLEAR
+ * 0x1000_141c: W1_MASK_CLEAR
+ *
+ * 7445:
+ * 0xf03e_1500: W0_STATUS
+ * 0xf03e_1504: W1_STATUS
+ * 0xf03e_1508: W2_STATUS
+ * 0xf03e_150c: W3_STATUS
+ * 0xf03e_1510: W4_STATUS
+ * 0xf03e_1514: W0_MASK_STATUS
+ * 0xf03e_1518: W1_MASK_STATUS
+ * [...]
+ */
+
+static inline unsigned int reg_status(struct bcm7038_l1_chip *intc,
+ unsigned int word)
+{
+ return (0 * intc->n_words + word) * sizeof(u32);
+}
+
+static inline unsigned int reg_mask_status(struct bcm7038_l1_chip *intc,
+ unsigned int word)
+{
+ return (1 * intc->n_words + word) * sizeof(u32);
+}
+
+static inline unsigned int reg_mask_set(struct bcm7038_l1_chip *intc,
+ unsigned int word)
+{
+ return (2 * intc->n_words + word) * sizeof(u32);
+}
+
+static inline unsigned int reg_mask_clr(struct bcm7038_l1_chip *intc,
+ unsigned int word)
+{
+ return (3 * intc->n_words + word) * sizeof(u32);
+}
+
+static inline u32 l1_readl(void __iomem *reg)
+{
+ if (IS_ENABLED(CONFIG_MIPS) && IS_ENABLED(CONFIG_CPU_BIG_ENDIAN))
+ return ioread32be(reg);
+ else
+ return readl(reg);
+}
+
+static inline void l1_writel(u32 val, void __iomem *reg)
+{
+ if (IS_ENABLED(CONFIG_MIPS) && IS_ENABLED(CONFIG_CPU_BIG_ENDIAN))
+ iowrite32be(val, reg);
+ else
+ writel(val, reg);
+}
+
+static void bcm7038_l1_irq_handle(unsigned int irq, struct irq_desc *desc)
+{
+ struct bcm7038_l1_chip *intc = irq_desc_get_handler_data(desc);
+ struct bcm7038_l1_cpu *cpu;
+ struct irq_chip *chip = irq_desc_get_chip(desc);
+ unsigned int idx;
+
+#ifdef CONFIG_SMP
+ cpu = intc->cpus[cpu_logical_map(smp_processor_id())];
+#else
+ cpu = intc->cpus[0];
+#endif
+
+ chained_irq_enter(chip, desc);
+
+ for (idx = 0; idx < intc->n_words; idx++) {
+ int base = idx * IRQS_PER_WORD;
+ unsigned long pending, flags;
+ int hwirq;
+
+ raw_spin_lock_irqsave(&intc->lock, flags);
+ pending = l1_readl(cpu->map_base + reg_status(intc, idx)) &
+ ~cpu->mask_cache[idx];
+ raw_spin_unlock_irqrestore(&intc->lock, flags);
+
+ for_each_set_bit(hwirq, &pending, IRQS_PER_WORD) {
+ generic_handle_irq(irq_find_mapping(intc->domain,
+ base + hwirq));
+ }
+ }
+
+ chained_irq_exit(chip, desc);
+}
+
+static void __bcm7038_l1_unmask(struct irq_data *d, unsigned int cpu_idx)
+{
+ struct bcm7038_l1_chip *intc = irq_data_get_irq_chip_data(d);
+ u32 word = d->hwirq / IRQS_PER_WORD;
+ u32 mask = BIT(d->hwirq % IRQS_PER_WORD);
+
+ intc->cpus[cpu_idx]->mask_cache[word] &= ~mask;
+ l1_writel(mask, intc->cpus[cpu_idx]->map_base +
+ reg_mask_clr(intc, word));
+}
+
+static void __bcm7038_l1_mask(struct irq_data *d, unsigned int cpu_idx)
+{
+ struct bcm7038_l1_chip *intc = irq_data_get_irq_chip_data(d);
+ u32 word = d->hwirq / IRQS_PER_WORD;
+ u32 mask = BIT(d->hwirq % IRQS_PER_WORD);
+
+ intc->cpus[cpu_idx]->mask_cache[word] |= mask;
+ l1_writel(mask, intc->cpus[cpu_idx]->map_base +
+ reg_mask_set(intc, word));
+}
+
+static void bcm7038_l1_unmask(struct irq_data *d)
+{
+ struct bcm7038_l1_chip *intc = irq_data_get_irq_chip_data(d);
+ unsigned long flags;
+
+ raw_spin_lock_irqsave(&intc->lock, flags);
+ __bcm7038_l1_unmask(d, intc->affinity[d->hwirq]);
+ raw_spin_unlock_irqrestore(&intc->lock, flags);
+}
+
+static void bcm7038_l1_mask(struct irq_data *d)
+{
+ struct bcm7038_l1_chip *intc = irq_data_get_irq_chip_data(d);
+ unsigned long flags;
+
+ raw_spin_lock_irqsave(&intc->lock, flags);
+ __bcm7038_l1_mask(d, intc->affinity[d->hwirq]);
+ raw_spin_unlock_irqrestore(&intc->lock, flags);
+}
+
+static int bcm7038_l1_set_affinity(struct irq_data *d,
+ const struct cpumask *dest,
+ bool force)
+{
+ struct bcm7038_l1_chip *intc = irq_data_get_irq_chip_data(d);
+ unsigned long flags;
+ irq_hw_number_t hw = d->hwirq;
+ u32 word = hw / IRQS_PER_WORD;
+ u32 mask = BIT(hw % IRQS_PER_WORD);
+ unsigned int first_cpu = cpumask_any_and(dest, cpu_online_mask);
+ bool was_disabled;
+
+ raw_spin_lock_irqsave(&intc->lock, flags);
+
+ was_disabled = !!(intc->cpus[intc->affinity[hw]]->mask_cache[word] &
+ mask);
+ __bcm7038_l1_mask(d, intc->affinity[hw]);
+ intc->affinity[hw] = first_cpu;
+ if (!was_disabled)
+ __bcm7038_l1_unmask(d, first_cpu);
+
+ raw_spin_unlock_irqrestore(&intc->lock, flags);
+ return 0;
+}
+
+static int __init bcm7038_l1_init_one(struct device_node *dn,
+ unsigned int idx,
+ struct bcm7038_l1_chip *intc)
+{
+ struct resource res;
+ resource_size_t sz;
+ struct bcm7038_l1_cpu *cpu;
+ unsigned int i, n_words, parent_irq;
+
+ if (of_address_to_resource(dn, idx, &res))
+ return -EINVAL;
+ sz = resource_size(&res);
+ n_words = sz / REG_BYTES_PER_IRQ_WORD;
+
+ if (n_words > MAX_WORDS)
+ return -EINVAL;
+ else if (!intc->n_words)
+ intc->n_words = n_words;
+ else if (intc->n_words != n_words)
+ return -EINVAL;
+
+ cpu = intc->cpus[idx] = kzalloc(sizeof(*cpu) + n_words * sizeof(u32),
+ GFP_KERNEL);
+ if (!cpu)
+ return -ENOMEM;
+
+ cpu->map_base = ioremap(res.start, sz);
+ if (!cpu->map_base)
+ return -ENOMEM;
+
+ for (i = 0; i < n_words; i++) {
+ l1_writel(0xffffffff, cpu->map_base + reg_mask_set(intc, i));
+ cpu->mask_cache[i] = 0xffffffff;
+ }
+
+ parent_irq = irq_of_parse_and_map(dn, idx);
+ if (!parent_irq) {
+ pr_err("failed to map parent interrupt %d\n", parent_irq);
+ return -EINVAL;
+ }
+ irq_set_handler_data(parent_irq, intc);
+ irq_set_chained_handler(parent_irq, bcm7038_l1_irq_handle);
+
+ return 0;
+}
+
+static struct irq_chip bcm7038_l1_irq_chip = {
+ .name = "bcm7038-l1",
+ .irq_mask = bcm7038_l1_mask,
+ .irq_unmask = bcm7038_l1_unmask,
+ .irq_set_affinity = bcm7038_l1_set_affinity,
+};
+
+static int bcm7038_l1_map(struct irq_domain *d, unsigned int virq,
+ irq_hw_number_t hw_irq)
+{
+ irq_set_chip_and_handler(virq, &bcm7038_l1_irq_chip, handle_level_irq);
+ irq_set_chip_data(virq, d->host_data);
+ return 0;
+}
+
+static const struct irq_domain_ops bcm7038_l1_domain_ops = {
+ .xlate = irq_domain_xlate_onecell,
+ .map = bcm7038_l1_map,
+};
+
+int __init bcm7038_l1_of_init(struct device_node *dn,
+ struct device_node *parent)
+{
+ struct bcm7038_l1_chip *intc;
+ int idx, ret;
+
+ intc = kzalloc(sizeof(*intc), GFP_KERNEL);
+ if (!intc)
+ return -ENOMEM;
+
+ raw_spin_lock_init(&intc->lock);
+ for_each_possible_cpu(idx) {
+ ret = bcm7038_l1_init_one(dn, idx, intc);
+ if (ret < 0) {
+ if (idx)
+ break;
+ pr_err("failed to remap intc L1 registers\n");
+ goto out_free;
+ }
+ }
+
+ intc->domain = irq_domain_add_linear(dn, IRQS_PER_WORD * intc->n_words,
+ &bcm7038_l1_domain_ops,
+ intc);
+ if (!intc->domain) {
+ ret = -ENOMEM;
+ goto out_unmap;
+ }
+
+ pr_info("registered BCM7038 L1 intc (mem: 0x%p, IRQs: %d)\n",
+ intc->cpus[0]->map_base, IRQS_PER_WORD * intc->n_words);
+
+ return 0;
+
+out_unmap:
+ for_each_possible_cpu(idx) {
+ struct bcm7038_l1_cpu *cpu = intc->cpus[idx];
+
+ if (cpu) {
+ if (cpu->map_base)
+ iounmap(cpu->map_base);
+ kfree(cpu);
+ }
+ }
+out_free:
+ kfree(intc);
+ return ret;
+}
+
+IRQCHIP_DECLARE(bcm7038_l1, "brcm,bcm7038-l1-intc", bcm7038_l1_of_init);