diff options
Diffstat (limited to 'drivers/irqchip/irq-brcmstb-l2.c')
| -rw-r--r-- | drivers/irqchip/irq-brcmstb-l2.c | 202 |
1 files changed, 202 insertions, 0 deletions
diff --git a/drivers/irqchip/irq-brcmstb-l2.c b/drivers/irqchip/irq-brcmstb-l2.c new file mode 100644 index 000000000000..8ee2a36d5840 --- /dev/null +++ b/drivers/irqchip/irq-brcmstb-l2.c @@ -0,0 +1,202 @@ +/* + * Generic Broadcom Set Top Box 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. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#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/irqchip.h> +#include <linux/irqchip/chained_irq.h> + +#include <asm/mach/irq.h> + +#include "irqchip.h" + +/* Register offsets in the L2 interrupt controller */ +#define CPU_STATUS 0x00 +#define CPU_SET 0x04 +#define CPU_CLEAR 0x08 +#define CPU_MASK_STATUS 0x0c +#define CPU_MASK_SET 0x10 +#define CPU_MASK_CLEAR 0x14 + +/* L2 intc private data structure */ +struct brcmstb_l2_intc_data { + int parent_irq; + void __iomem *base; + struct irq_domain *domain; + bool can_wake; + u32 saved_mask; /* for suspend/resume */ +}; + +static void brcmstb_l2_intc_irq_handle(unsigned int irq, struct irq_desc *desc) +{ + struct brcmstb_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 + CPU_STATUS) & + ~(__raw_readl(b->base + CPU_MASK_STATUS)); + + if (status == 0) { + do_bad_IRQ(irq, desc); + goto out; + } + + do { + irq = ffs(status) - 1; + /* ack at our level */ + __raw_writel(1 << irq, b->base + CPU_CLEAR); + status &= ~(1 << irq); + generic_handle_irq(irq_find_mapping(b->domain, irq)); + } while (status); +out: + chained_irq_exit(chip, desc); +} + +static void brcmstb_l2_intc_suspend(struct irq_data *d) +{ + struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d); + struct brcmstb_l2_intc_data *b = gc->private; + + irq_gc_lock(gc); + /* Save the current mask */ + b->saved_mask = __raw_readl(b->base + CPU_MASK_STATUS); + + if (b->can_wake) { + /* Program the wakeup mask */ + __raw_writel(~gc->wake_active, b->base + CPU_MASK_SET); + __raw_writel(gc->wake_active, b->base + CPU_MASK_CLEAR); + } + irq_gc_unlock(gc); +} + +static void brcmstb_l2_intc_resume(struct irq_data *d) +{ + struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d); + struct brcmstb_l2_intc_data *b = gc->private; + + irq_gc_lock(gc); + /* Clear unmasked non-wakeup interrupts */ + __raw_writel(~b->saved_mask & ~gc->wake_active, b->base + CPU_CLEAR); + + /* Restore the saved mask */ + __raw_writel(b->saved_mask, b->base + CPU_MASK_SET); + __raw_writel(~b->saved_mask, b->base + CPU_MASK_CLEAR); + irq_gc_unlock(gc); +} + +int __init brcmstb_l2_intc_of_init(struct device_node *np, + struct device_node *parent) +{ + unsigned int clr = IRQ_NOREQUEST | IRQ_NOPROBE | IRQ_NOAUTOEN; + struct brcmstb_l2_intc_data *data; + struct irq_chip_generic *gc; + struct irq_chip_type *ct; + int ret; + + data = kzalloc(sizeof(*data), GFP_KERNEL); + if (!data) + return -ENOMEM; + + data->base = of_iomap(np, 0); + if (!data->base) { + pr_err("failed to remap intc L2 registers\n"); + ret = -ENOMEM; + goto out_free; + } + + /* Disable all interrupts by default */ + __raw_writel(0xffffffff, data->base + CPU_MASK_SET); + __raw_writel(0xffffffff, data->base + CPU_CLEAR); + + data->parent_irq = irq_of_parse_and_map(np, 0); + if (data->parent_irq < 0) { + pr_err("failed to find parent interrupt\n"); + ret = data->parent_irq; + goto out_unmap; + } + + data->domain = irq_domain_add_linear(np, 32, + &irq_generic_chip_ops, NULL); + if (!data->domain) { + ret = -ENOMEM; + goto out_unmap; + } + + /* Allocate a single Generic IRQ chip for this node */ + ret = irq_alloc_domain_generic_chips(data->domain, 32, 1, + np->full_name, handle_level_irq, clr, 0, 0); + if (ret) { + pr_err("failed to allocate generic irq chip\n"); + goto out_free_domain; + } + + /* Set the IRQ chaining logic */ + irq_set_handler_data(data->parent_irq, data); + irq_set_chained_handler(data->parent_irq, brcmstb_l2_intc_irq_handle); + + gc = irq_get_domain_generic_chip(data->domain, 0); + gc->reg_base = data->base; + gc->private = data; + ct = gc->chip_types; + + ct->chip.irq_ack = irq_gc_ack_set_bit; + ct->regs.ack = CPU_CLEAR; + + ct->chip.irq_mask = irq_gc_mask_disable_reg; + ct->regs.disable = CPU_MASK_SET; + + ct->chip.irq_unmask = irq_gc_unmask_enable_reg; + ct->regs.enable = CPU_MASK_CLEAR; + + ct->chip.irq_suspend = brcmstb_l2_intc_suspend; + ct->chip.irq_resume = brcmstb_l2_intc_resume; + + if (of_property_read_bool(np, "brcm,irq-can-wake")) { + data->can_wake = true; + /* This IRQ chip can wake the system, set all child interrupts + * in wake_enabled mask + */ + gc->wake_enabled = 0xffffffff; + ct->chip.irq_set_wake = irq_gc_set_wake; + } + + pr_info("registered L2 intc (mem: 0x%p, parent irq: %d)\n", + data->base, data->parent_irq); + + 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,l2-intc", brcmstb_l2_intc_of_init); |