diff options
Diffstat (limited to 'drivers/irqchip/irq-bcm7038-l1.c')
| -rw-r--r-- | drivers/irqchip/irq-bcm7038-l1.c | 335 |
1 files changed, 335 insertions, 0 deletions
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); |