diff options
Diffstat (limited to 'drivers/irqchip/irq-gemini.c')
| -rw-r--r-- | drivers/irqchip/irq-gemini.c | 185 |
1 files changed, 185 insertions, 0 deletions
diff --git a/drivers/irqchip/irq-gemini.c b/drivers/irqchip/irq-gemini.c new file mode 100644 index 000000000000..495224c743ee --- /dev/null +++ b/drivers/irqchip/irq-gemini.c @@ -0,0 +1,185 @@ +/* + * irqchip for the Cortina Systems Gemini Copyright (C) 2017 Linus + * Walleij <linus.walleij@linaro.org> + * + * Based on arch/arm/mach-gemini/irq.c + * Copyright (C) 2001-2006 Storlink, Corp. + * Copyright (C) 2008-2009 Paulius Zaleckas <paulius.zaleckas@teltonika.lt> + */ +#include <linux/bitops.h> +#include <linux/irq.h> +#include <linux/io.h> +#include <linux/irqchip.h> +#include <linux/irqchip/versatile-fpga.h> +#include <linux/irqdomain.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/of_irq.h> +#include <linux/cpu.h> + +#include <asm/exception.h> +#include <asm/mach/irq.h> + +#define GEMINI_NUM_IRQS 32 + +#define GEMINI_IRQ_SOURCE(base_addr) (base_addr + 0x00) +#define GEMINI_IRQ_MASK(base_addr) (base_addr + 0x04) +#define GEMINI_IRQ_CLEAR(base_addr) (base_addr + 0x08) +#define GEMINI_IRQ_MODE(base_addr) (base_addr + 0x0C) +#define GEMINI_IRQ_POLARITY(base_addr) (base_addr + 0x10) +#define GEMINI_IRQ_STATUS(base_addr) (base_addr + 0x14) +#define GEMINI_FIQ_SOURCE(base_addr) (base_addr + 0x20) +#define GEMINI_FIQ_MASK(base_addr) (base_addr + 0x24) +#define GEMINI_FIQ_CLEAR(base_addr) (base_addr + 0x28) +#define GEMINI_FIQ_MODE(base_addr) (base_addr + 0x2C) +#define GEMINI_FIQ_POLARITY(base_addr) (base_addr + 0x30) +#define GEMINI_FIQ_STATUS(base_addr) (base_addr + 0x34) + +/** + * struct gemini_irq_data - irq data container for the Gemini IRQ controller + * @base: memory offset in virtual memory + * @chip: chip container for this instance + * @domain: IRQ domain for this instance + */ +struct gemini_irq_data { + void __iomem *base; + struct irq_chip chip; + struct irq_domain *domain; +}; + +static void gemini_irq_mask(struct irq_data *d) +{ + struct gemini_irq_data *g = irq_data_get_irq_chip_data(d); + unsigned int mask; + + mask = readl(GEMINI_IRQ_MASK(g->base)); + mask &= ~BIT(irqd_to_hwirq(d)); + writel(mask, GEMINI_IRQ_MASK(g->base)); +} + +static void gemini_irq_unmask(struct irq_data *d) +{ + struct gemini_irq_data *g = irq_data_get_irq_chip_data(d); + unsigned int mask; + + mask = readl(GEMINI_IRQ_MASK(g->base)); + mask |= BIT(irqd_to_hwirq(d)); + writel(mask, GEMINI_IRQ_MASK(g->base)); +} + +static void gemini_irq_ack(struct irq_data *d) +{ + struct gemini_irq_data *g = irq_data_get_irq_chip_data(d); + + writel(BIT(irqd_to_hwirq(d)), GEMINI_IRQ_CLEAR(g->base)); +} + +static int gemini_irq_set_type(struct irq_data *d, unsigned int trigger) +{ + struct gemini_irq_data *g = irq_data_get_irq_chip_data(d); + int offset = irqd_to_hwirq(d); + u32 mode, polarity; + + mode = readl(GEMINI_IRQ_MODE(g->base)); + polarity = readl(GEMINI_IRQ_POLARITY(g->base)); + + if (trigger & (IRQ_TYPE_LEVEL_HIGH)) { + irq_set_handler_locked(d, handle_level_irq); + /* Disable edge detection */ + mode &= ~BIT(offset); + polarity &= ~BIT(offset); + } else if (trigger & IRQ_TYPE_EDGE_RISING) { + irq_set_handler_locked(d, handle_edge_irq); + mode |= BIT(offset); + polarity |= BIT(offset); + } else if (trigger & IRQ_TYPE_EDGE_FALLING) { + irq_set_handler_locked(d, handle_edge_irq); + mode |= BIT(offset); + polarity &= ~BIT(offset); + } else { + irq_set_handler_locked(d, handle_bad_irq); + pr_warn("GEMINI IRQ: no supported trigger selected for line %d\n", + offset); + } + + writel(mode, GEMINI_IRQ_MODE(g->base)); + writel(polarity, GEMINI_IRQ_POLARITY(g->base)); + + return 0; +} + +static struct irq_chip gemini_irq_chip = { + .name = "GEMINI", + .irq_ack = gemini_irq_ack, + .irq_mask = gemini_irq_mask, + .irq_unmask = gemini_irq_unmask, + .irq_set_type = gemini_irq_set_type, +}; + +/* Local static for the IRQ entry call */ +static struct gemini_irq_data girq; + +asmlinkage void __exception_irq_entry gemini_irqchip_handle_irq(struct pt_regs *regs) +{ + struct gemini_irq_data *g = &girq; + int irq; + u32 status; + + while ((status = readl(GEMINI_IRQ_STATUS(g->base)))) { + irq = ffs(status) - 1; + handle_domain_irq(g->domain, irq, regs); + } +} + +static int gemini_irqdomain_map(struct irq_domain *d, unsigned int irq, + irq_hw_number_t hwirq) +{ + struct gemini_irq_data *g = d->host_data; + + irq_set_chip_data(irq, g); + /* All IRQs should set up their type, flags as bad by default */ + irq_set_chip_and_handler(irq, &gemini_irq_chip, handle_bad_irq); + irq_set_probe(irq); + + return 0; +} + +static void gemini_irqdomain_unmap(struct irq_domain *d, unsigned int irq) +{ + irq_set_chip_and_handler(irq, NULL, NULL); + irq_set_chip_data(irq, NULL); +} + +static const struct irq_domain_ops gemini_irqdomain_ops = { + .map = gemini_irqdomain_map, + .unmap = gemini_irqdomain_unmap, + .xlate = irq_domain_xlate_onetwocell, +}; + +int __init gemini_of_init_irq(struct device_node *node, + struct device_node *parent) +{ + struct gemini_irq_data *g = &girq; + + /* + * Disable the idle handler by default since it is buggy + * For more info see arch/arm/mach-gemini/idle.c + */ + cpu_idle_poll_ctrl(true); + + g->base = of_iomap(node, 0); + WARN(!g->base, "unable to map gemini irq registers\n"); + + /* Disable all interrupts */ + writel(0, GEMINI_IRQ_MASK(g->base)); + writel(0, GEMINI_FIQ_MASK(g->base)); + + g->domain = irq_domain_add_simple(node, GEMINI_NUM_IRQS, 0, + &gemini_irqdomain_ops, g); + set_handle_irq(gemini_irqchip_handle_irq); + + return 0; +} +IRQCHIP_DECLARE(gemini, "cortina,gemini-interrupt-controller", + gemini_of_init_irq); |