diff options
Diffstat (limited to 'drivers/irqchip/irq-bcm6345-l1.c')
| -rw-r--r-- | drivers/irqchip/irq-bcm6345-l1.c | 364 |
1 files changed, 364 insertions, 0 deletions
diff --git a/drivers/irqchip/irq-bcm6345-l1.c b/drivers/irqchip/irq-bcm6345-l1.c new file mode 100644 index 000000000..b844c89a9 --- /dev/null +++ b/drivers/irqchip/irq-bcm6345-l1.c @@ -0,0 +1,364 @@ +/* + * Broadcom BCM6345 style Level 1 interrupt controller driver + * + * Copyright (C) 2014 Broadcom Corporation + * Copyright 2015 Simon Arlott + * + * 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. + * + * This is based on the BCM7038 (which supports SMP) but with a single + * enable register instead of separate mask/set/clear registers. + * + * The BCM3380 has a similar mask/status register layout, but each pair + * of words is at separate locations (and SMP is not supported). + * + * ENABLE/STATUS words are packed next to each other for each CPU: + * + * BCM6368: + * 0x1000_0020: CPU0_W0_ENABLE + * 0x1000_0024: CPU0_W1_ENABLE + * 0x1000_0028: CPU0_W0_STATUS IRQs 31-63 + * 0x1000_002c: CPU0_W1_STATUS IRQs 0-31 + * 0x1000_0030: CPU1_W0_ENABLE + * 0x1000_0034: CPU1_W1_ENABLE + * 0x1000_0038: CPU1_W0_STATUS IRQs 31-63 + * 0x1000_003c: CPU1_W1_STATUS IRQs 0-31 + * + * BCM63168: + * 0x1000_0020: CPU0_W0_ENABLE + * 0x1000_0024: CPU0_W1_ENABLE + * 0x1000_0028: CPU0_W2_ENABLE + * 0x1000_002c: CPU0_W3_ENABLE + * 0x1000_0030: CPU0_W0_STATUS IRQs 96-127 + * 0x1000_0034: CPU0_W1_STATUS IRQs 64-95 + * 0x1000_0038: CPU0_W2_STATUS IRQs 32-63 + * 0x1000_003c: CPU0_W3_STATUS IRQs 0-31 + * 0x1000_0040: CPU1_W0_ENABLE + * 0x1000_0044: CPU1_W1_ENABLE + * 0x1000_0048: CPU1_W2_ENABLE + * 0x1000_004c: CPU1_W3_ENABLE + * 0x1000_0050: CPU1_W0_STATUS IRQs 96-127 + * 0x1000_0054: CPU1_W1_STATUS IRQs 64-95 + * 0x1000_0058: CPU1_W2_STATUS IRQs 32-63 + * 0x1000_005c: CPU1_W3_STATUS IRQs 0-31 + * + * IRQs are numbered in CPU native endian order + * (which is big-endian in these examples) + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/bitops.h> +#include <linux/cpumask.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.h> +#include <linux/irqchip/chained_irq.h> + +#define IRQS_PER_WORD 32 +#define REG_BYTES_PER_IRQ_WORD (sizeof(u32) * 2) + +struct bcm6345_l1_cpu; + +struct bcm6345_l1_chip { + raw_spinlock_t lock; + unsigned int n_words; + struct irq_domain *domain; + struct cpumask cpumask; + struct bcm6345_l1_cpu *cpus[NR_CPUS]; +}; + +struct bcm6345_l1_cpu { + void __iomem *map_base; + unsigned int parent_irq; + u32 enable_cache[]; +}; + +static inline unsigned int reg_enable(struct bcm6345_l1_chip *intc, + unsigned int word) +{ +#ifdef __BIG_ENDIAN + return (1 * intc->n_words - word - 1) * sizeof(u32); +#else + return (0 * intc->n_words + word) * sizeof(u32); +#endif +} + +static inline unsigned int reg_status(struct bcm6345_l1_chip *intc, + unsigned int word) +{ +#ifdef __BIG_ENDIAN + return (2 * intc->n_words - word - 1) * sizeof(u32); +#else + return (1 * intc->n_words + word) * sizeof(u32); +#endif +} + +static inline unsigned int cpu_for_irq(struct bcm6345_l1_chip *intc, + struct irq_data *d) +{ + return cpumask_first_and(&intc->cpumask, irq_data_get_affinity_mask(d)); +} + +static void bcm6345_l1_irq_handle(struct irq_desc *desc) +{ + struct bcm6345_l1_chip *intc = irq_desc_get_handler_data(desc); + struct bcm6345_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; + irq_hw_number_t hwirq; + unsigned int irq; + + pending = __raw_readl(cpu->map_base + reg_status(intc, idx)); + pending &= __raw_readl(cpu->map_base + reg_enable(intc, idx)); + + for_each_set_bit(hwirq, &pending, IRQS_PER_WORD) { + irq = irq_linear_revmap(intc->domain, base + hwirq); + if (irq) + do_IRQ(irq); + else + spurious_interrupt(); + } + } + + chained_irq_exit(chip, desc); +} + +static inline void __bcm6345_l1_unmask(struct irq_data *d) +{ + struct bcm6345_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); + unsigned int cpu_idx = cpu_for_irq(intc, d); + + intc->cpus[cpu_idx]->enable_cache[word] |= mask; + __raw_writel(intc->cpus[cpu_idx]->enable_cache[word], + intc->cpus[cpu_idx]->map_base + reg_enable(intc, word)); +} + +static inline void __bcm6345_l1_mask(struct irq_data *d) +{ + struct bcm6345_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); + unsigned int cpu_idx = cpu_for_irq(intc, d); + + intc->cpus[cpu_idx]->enable_cache[word] &= ~mask; + __raw_writel(intc->cpus[cpu_idx]->enable_cache[word], + intc->cpus[cpu_idx]->map_base + reg_enable(intc, word)); +} + +static void bcm6345_l1_unmask(struct irq_data *d) +{ + struct bcm6345_l1_chip *intc = irq_data_get_irq_chip_data(d); + unsigned long flags; + + raw_spin_lock_irqsave(&intc->lock, flags); + __bcm6345_l1_unmask(d); + raw_spin_unlock_irqrestore(&intc->lock, flags); +} + +static void bcm6345_l1_mask(struct irq_data *d) +{ + struct bcm6345_l1_chip *intc = irq_data_get_irq_chip_data(d); + unsigned long flags; + + raw_spin_lock_irqsave(&intc->lock, flags); + __bcm6345_l1_mask(d); + raw_spin_unlock_irqrestore(&intc->lock, flags); +} + +static int bcm6345_l1_set_affinity(struct irq_data *d, + const struct cpumask *dest, + bool force) +{ + struct bcm6345_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); + unsigned int old_cpu = cpu_for_irq(intc, d); + unsigned int new_cpu; + struct cpumask valid; + unsigned long flags; + bool enabled; + + if (!cpumask_and(&valid, &intc->cpumask, dest)) + return -EINVAL; + + new_cpu = cpumask_any_and(&valid, cpu_online_mask); + if (new_cpu >= nr_cpu_ids) + return -EINVAL; + + dest = cpumask_of(new_cpu); + + raw_spin_lock_irqsave(&intc->lock, flags); + if (old_cpu != new_cpu) { + enabled = intc->cpus[old_cpu]->enable_cache[word] & mask; + if (enabled) + __bcm6345_l1_mask(d); + cpumask_copy(irq_data_get_affinity_mask(d), dest); + if (enabled) + __bcm6345_l1_unmask(d); + } else { + cpumask_copy(irq_data_get_affinity_mask(d), dest); + } + raw_spin_unlock_irqrestore(&intc->lock, flags); + + return IRQ_SET_MASK_OK_NOCOPY; +} + +static int __init bcm6345_l1_init_one(struct device_node *dn, + unsigned int idx, + struct bcm6345_l1_chip *intc) +{ + struct resource res; + resource_size_t sz; + struct bcm6345_l1_cpu *cpu; + unsigned int i, n_words; + + if (of_address_to_resource(dn, idx, &res)) + return -EINVAL; + sz = resource_size(&res); + n_words = sz / REG_BYTES_PER_IRQ_WORD; + + 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++) { + cpu->enable_cache[i] = 0; + __raw_writel(0, cpu->map_base + reg_enable(intc, i)); + } + + cpu->parent_irq = irq_of_parse_and_map(dn, idx); + if (!cpu->parent_irq) { + pr_err("failed to map parent interrupt %d\n", cpu->parent_irq); + return -EINVAL; + } + irq_set_chained_handler_and_data(cpu->parent_irq, + bcm6345_l1_irq_handle, intc); + + return 0; +} + +static struct irq_chip bcm6345_l1_irq_chip = { + .name = "bcm6345-l1", + .irq_mask = bcm6345_l1_mask, + .irq_unmask = bcm6345_l1_unmask, + .irq_set_affinity = bcm6345_l1_set_affinity, +}; + +static int bcm6345_l1_map(struct irq_domain *d, unsigned int virq, + irq_hw_number_t hw_irq) +{ + irq_set_chip_and_handler(virq, + &bcm6345_l1_irq_chip, handle_percpu_irq); + irq_set_chip_data(virq, d->host_data); + return 0; +} + +static const struct irq_domain_ops bcm6345_l1_domain_ops = { + .xlate = irq_domain_xlate_onecell, + .map = bcm6345_l1_map, +}; + +static int __init bcm6345_l1_of_init(struct device_node *dn, + struct device_node *parent) +{ + struct bcm6345_l1_chip *intc; + unsigned int idx; + int ret; + + intc = kzalloc(sizeof(*intc), GFP_KERNEL); + if (!intc) + return -ENOMEM; + + for_each_possible_cpu(idx) { + ret = bcm6345_l1_init_one(dn, idx, intc); + if (ret) + pr_err("failed to init intc L1 for cpu %d: %d\n", + idx, ret); + else + cpumask_set_cpu(idx, &intc->cpumask); + } + + if (!cpumask_weight(&intc->cpumask)) { + ret = -ENODEV; + goto out_free; + } + + raw_spin_lock_init(&intc->lock); + + intc->domain = irq_domain_add_linear(dn, IRQS_PER_WORD * intc->n_words, + &bcm6345_l1_domain_ops, + intc); + if (!intc->domain) { + ret = -ENOMEM; + goto out_unmap; + } + + pr_info("registered BCM6345 L1 intc (IRQs: %d)\n", + IRQS_PER_WORD * intc->n_words); + for_each_cpu(idx, &intc->cpumask) { + struct bcm6345_l1_cpu *cpu = intc->cpus[idx]; + + pr_info(" CPU%u at MMIO 0x%p (irq = %d)\n", idx, + cpu->map_base, cpu->parent_irq); + } + + return 0; + +out_unmap: + for_each_possible_cpu(idx) { + struct bcm6345_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(bcm6345_l1, "brcm,bcm6345-l1-intc", bcm6345_l1_of_init); |