diff options
Diffstat (limited to 'drivers/irqchip/irq-ixp4xx.c')
| -rw-r--r-- | drivers/irqchip/irq-ixp4xx.c | 403 |
1 files changed, 403 insertions, 0 deletions
diff --git a/drivers/irqchip/irq-ixp4xx.c b/drivers/irqchip/irq-ixp4xx.c new file mode 100644 index 000000000..37e074921 --- /dev/null +++ b/drivers/irqchip/irq-ixp4xx.c @@ -0,0 +1,403 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * irqchip for the IXP4xx interrupt controller + * Copyright (C) 2019 Linus Walleij <linus.walleij@linaro.org> + * + * Based on arch/arm/mach-ixp4xx/common.c + * Copyright 2002 (C) Intel Corporation + * Copyright 2003-2004 (C) MontaVista, Software, Inc. + * Copyright (C) Deepak Saxena <dsaxena@plexity.net> + */ +#include <linux/bitops.h> +#include <linux/gpio/driver.h> +#include <linux/irq.h> +#include <linux/io.h> +#include <linux/irqchip.h> +#include <linux/irqchip/irq-ixp4xx.h> +#include <linux/irqdomain.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/of_irq.h> +#include <linux/platform_device.h> +#include <linux/cpu.h> + +#include <asm/exception.h> +#include <asm/mach/irq.h> + +#define IXP4XX_ICPR 0x00 /* Interrupt Status */ +#define IXP4XX_ICMR 0x04 /* Interrupt Enable */ +#define IXP4XX_ICLR 0x08 /* Interrupt IRQ/FIQ Select */ +#define IXP4XX_ICIP 0x0C /* IRQ Status */ +#define IXP4XX_ICFP 0x10 /* FIQ Status */ +#define IXP4XX_ICHR 0x14 /* Interrupt Priority */ +#define IXP4XX_ICIH 0x18 /* IRQ Highest Pri Int */ +#define IXP4XX_ICFH 0x1C /* FIQ Highest Pri Int */ + +/* IXP43x and IXP46x-only */ +#define IXP4XX_ICPR2 0x20 /* Interrupt Status 2 */ +#define IXP4XX_ICMR2 0x24 /* Interrupt Enable 2 */ +#define IXP4XX_ICLR2 0x28 /* Interrupt IRQ/FIQ Select 2 */ +#define IXP4XX_ICIP2 0x2C /* IRQ Status */ +#define IXP4XX_ICFP2 0x30 /* FIQ Status */ +#define IXP4XX_ICEEN 0x34 /* Error High Pri Enable */ + +/** + * struct ixp4xx_irq - state container for the Faraday IRQ controller + * @irqbase: IRQ controller memory base in virtual memory + * @is_356: if this is an IXP43x, IXP45x or IX46x SoC (with 64 IRQs) + * @irqchip: irqchip for this instance + * @domain: IRQ domain for this instance + */ +struct ixp4xx_irq { + void __iomem *irqbase; + bool is_356; + struct irq_chip irqchip; + struct irq_domain *domain; +}; + +/* Local static state container */ +static struct ixp4xx_irq ixirq; + +/* GPIO Clocks */ +#define IXP4XX_GPIO_CLK_0 14 +#define IXP4XX_GPIO_CLK_1 15 + +static int ixp4xx_set_irq_type(struct irq_data *d, unsigned int type) +{ + /* All are level active high (asserted) here */ + if (type != IRQ_TYPE_LEVEL_HIGH) + return -EINVAL; + return 0; +} + +static void ixp4xx_irq_mask(struct irq_data *d) +{ + struct ixp4xx_irq *ixi = irq_data_get_irq_chip_data(d); + u32 val; + + if (ixi->is_356 && d->hwirq >= 32) { + val = __raw_readl(ixi->irqbase + IXP4XX_ICMR2); + val &= ~BIT(d->hwirq - 32); + __raw_writel(val, ixi->irqbase + IXP4XX_ICMR2); + } else { + val = __raw_readl(ixi->irqbase + IXP4XX_ICMR); + val &= ~BIT(d->hwirq); + __raw_writel(val, ixi->irqbase + IXP4XX_ICMR); + } +} + +/* + * Level triggered interrupts on GPIO lines can only be cleared when the + * interrupt condition disappears. + */ +static void ixp4xx_irq_unmask(struct irq_data *d) +{ + struct ixp4xx_irq *ixi = irq_data_get_irq_chip_data(d); + u32 val; + + if (ixi->is_356 && d->hwirq >= 32) { + val = __raw_readl(ixi->irqbase + IXP4XX_ICMR2); + val |= BIT(d->hwirq - 32); + __raw_writel(val, ixi->irqbase + IXP4XX_ICMR2); + } else { + val = __raw_readl(ixi->irqbase + IXP4XX_ICMR); + val |= BIT(d->hwirq); + __raw_writel(val, ixi->irqbase + IXP4XX_ICMR); + } +} + +asmlinkage void __exception_irq_entry ixp4xx_handle_irq(struct pt_regs *regs) +{ + struct ixp4xx_irq *ixi = &ixirq; + unsigned long status; + int i; + + status = __raw_readl(ixi->irqbase + IXP4XX_ICIP); + for_each_set_bit(i, &status, 32) + handle_domain_irq(ixi->domain, i, regs); + + /* + * IXP465/IXP435 has an upper IRQ status register + */ + if (ixi->is_356) { + status = __raw_readl(ixi->irqbase + IXP4XX_ICIP2); + for_each_set_bit(i, &status, 32) + handle_domain_irq(ixi->domain, i + 32, regs); + } +} + +static int ixp4xx_irq_domain_translate(struct irq_domain *domain, + struct irq_fwspec *fwspec, + unsigned long *hwirq, + unsigned int *type) +{ + /* We support standard DT translation */ + if (is_of_node(fwspec->fwnode) && fwspec->param_count == 2) { + *hwirq = fwspec->param[0]; + *type = fwspec->param[1]; + return 0; + } + + if (is_fwnode_irqchip(fwspec->fwnode)) { + if (fwspec->param_count != 2) + return -EINVAL; + *hwirq = fwspec->param[0]; + *type = fwspec->param[1]; + WARN_ON(*type == IRQ_TYPE_NONE); + return 0; + } + + return -EINVAL; +} + +static int ixp4xx_irq_domain_alloc(struct irq_domain *d, + unsigned int irq, unsigned int nr_irqs, + void *data) +{ + struct ixp4xx_irq *ixi = d->host_data; + irq_hw_number_t hwirq; + unsigned int type = IRQ_TYPE_NONE; + struct irq_fwspec *fwspec = data; + int ret; + int i; + + ret = ixp4xx_irq_domain_translate(d, fwspec, &hwirq, &type); + if (ret) + return ret; + + for (i = 0; i < nr_irqs; i++) { + /* + * TODO: after converting IXP4xx to only device tree, set + * handle_bad_irq as default handler and assume all consumers + * call .set_type() as this is provided in the second cell in + * the device tree phandle. + */ + irq_domain_set_info(d, + irq + i, + hwirq + i, + &ixi->irqchip, + ixi, + handle_level_irq, + NULL, NULL); + irq_set_probe(irq + i); + } + + return 0; +} + +/* + * This needs to be a hierarchical irqdomain to work well with the + * GPIO irqchip (which is lower in the hierarchy) + */ +static const struct irq_domain_ops ixp4xx_irqdomain_ops = { + .translate = ixp4xx_irq_domain_translate, + .alloc = ixp4xx_irq_domain_alloc, + .free = irq_domain_free_irqs_common, +}; + +/** + * ixp4xx_get_irq_domain() - retrieve the ixp4xx irq domain + * + * This function will go away when we transition to DT probing. + */ +struct irq_domain *ixp4xx_get_irq_domain(void) +{ + struct ixp4xx_irq *ixi = &ixirq; + + return ixi->domain; +} +EXPORT_SYMBOL_GPL(ixp4xx_get_irq_domain); + +/* + * This is the Linux IRQ to hwirq mapping table. This goes away when + * we have DT support as all IRQ resources are defined in the device + * tree. It will register all the IRQs that are not used by the hierarchical + * GPIO IRQ chip. The "holes" inbetween these IRQs will be requested by + * the GPIO driver using . This is a step-gap solution. + */ +struct ixp4xx_irq_chunk { + int irq; + int hwirq; + int nr_irqs; +}; + +static const struct ixp4xx_irq_chunk ixp4xx_irq_chunks[] = { + { + .irq = 16, + .hwirq = 0, + .nr_irqs = 6, + }, + { + .irq = 24, + .hwirq = 8, + .nr_irqs = 11, + }, + { + .irq = 46, + .hwirq = 30, + .nr_irqs = 2, + }, + /* Only on the 436 variants */ + { + .irq = 48, + .hwirq = 32, + .nr_irqs = 10, + }, +}; + +/** + * ixp4x_irq_setup() - Common setup code for the IXP4xx interrupt controller + * @ixi: State container + * @irqbase: Virtual memory base for the interrupt controller + * @fwnode: Corresponding fwnode abstraction for this controller + * @is_356: if this is an IXP43x, IXP45x or IXP46x SoC variant + */ +static int __init ixp4xx_irq_setup(struct ixp4xx_irq *ixi, + void __iomem *irqbase, + struct fwnode_handle *fwnode, + bool is_356) +{ + int nr_irqs; + + ixi->irqbase = irqbase; + ixi->is_356 = is_356; + + /* Route all sources to IRQ instead of FIQ */ + __raw_writel(0x0, ixi->irqbase + IXP4XX_ICLR); + + /* Disable all interrupts */ + __raw_writel(0x0, ixi->irqbase + IXP4XX_ICMR); + + if (is_356) { + /* Route upper 32 sources to IRQ instead of FIQ */ + __raw_writel(0x0, ixi->irqbase + IXP4XX_ICLR2); + + /* Disable upper 32 interrupts */ + __raw_writel(0x0, ixi->irqbase + IXP4XX_ICMR2); + + nr_irqs = 64; + } else { + nr_irqs = 32; + } + + ixi->irqchip.name = "IXP4xx"; + ixi->irqchip.irq_mask = ixp4xx_irq_mask; + ixi->irqchip.irq_unmask = ixp4xx_irq_unmask; + ixi->irqchip.irq_set_type = ixp4xx_set_irq_type; + + ixi->domain = irq_domain_create_linear(fwnode, nr_irqs, + &ixp4xx_irqdomain_ops, + ixi); + if (!ixi->domain) { + pr_crit("IXP4XX: can not add primary irqdomain\n"); + return -ENODEV; + } + + set_handle_irq(ixp4xx_handle_irq); + + return 0; +} + +/** + * ixp4xx_irq_init() - Function to initialize the irqchip from boardfiles + * @irqbase: physical base for the irq controller + * @is_356: if this is an IXP43x, IXP45x or IXP46x SoC variant + */ +void __init ixp4xx_irq_init(resource_size_t irqbase, + bool is_356) +{ + struct ixp4xx_irq *ixi = &ixirq; + void __iomem *base; + struct fwnode_handle *fwnode; + struct irq_fwspec fwspec; + int nr_chunks; + int ret; + int i; + + base = ioremap(irqbase, 0x100); + if (!base) { + pr_crit("IXP4XX: could not ioremap interrupt controller\n"); + return; + } + fwnode = irq_domain_alloc_fwnode(&irqbase); + if (!fwnode) { + pr_crit("IXP4XX: no domain handle\n"); + return; + } + ret = ixp4xx_irq_setup(ixi, base, fwnode, is_356); + if (ret) { + pr_crit("IXP4XX: failed to set up irqchip\n"); + irq_domain_free_fwnode(fwnode); + } + + nr_chunks = ARRAY_SIZE(ixp4xx_irq_chunks); + if (!is_356) + nr_chunks--; + + /* + * After adding OF support, this is no longer needed: irqs + * will be allocated for the respective fwnodes. + */ + for (i = 0; i < nr_chunks; i++) { + const struct ixp4xx_irq_chunk *chunk = &ixp4xx_irq_chunks[i]; + + pr_info("Allocate Linux IRQs %d..%d HW IRQs %d..%d\n", + chunk->irq, chunk->irq + chunk->nr_irqs - 1, + chunk->hwirq, chunk->hwirq + chunk->nr_irqs - 1); + fwspec.fwnode = fwnode; + fwspec.param[0] = chunk->hwirq; + fwspec.param[1] = IRQ_TYPE_LEVEL_HIGH; + fwspec.param_count = 2; + ret = __irq_domain_alloc_irqs(ixi->domain, + chunk->irq, + chunk->nr_irqs, + NUMA_NO_NODE, + &fwspec, + false, + NULL); + if (ret < 0) { + pr_crit("IXP4XX: can not allocate irqs in hierarchy %d\n", + ret); + return; + } + } +} +EXPORT_SYMBOL_GPL(ixp4xx_irq_init); + +#ifdef CONFIG_OF +int __init ixp4xx_of_init_irq(struct device_node *np, + struct device_node *parent) +{ + struct ixp4xx_irq *ixi = &ixirq; + void __iomem *base; + struct fwnode_handle *fwnode; + bool is_356; + int ret; + + base = of_iomap(np, 0); + if (!base) { + pr_crit("IXP4XX: could not ioremap interrupt controller\n"); + return -ENODEV; + } + fwnode = of_node_to_fwnode(np); + + /* These chip variants have 64 interrupts */ + is_356 = of_device_is_compatible(np, "intel,ixp43x-interrupt") || + of_device_is_compatible(np, "intel,ixp45x-interrupt") || + of_device_is_compatible(np, "intel,ixp46x-interrupt"); + + ret = ixp4xx_irq_setup(ixi, base, fwnode, is_356); + if (ret) + pr_crit("IXP4XX: failed to set up irqchip\n"); + + return ret; +} +IRQCHIP_DECLARE(ixp42x, "intel,ixp42x-interrupt", + ixp4xx_of_init_irq); +IRQCHIP_DECLARE(ixp43x, "intel,ixp43x-interrupt", + ixp4xx_of_init_irq); +IRQCHIP_DECLARE(ixp45x, "intel,ixp45x-interrupt", + ixp4xx_of_init_irq); +IRQCHIP_DECLARE(ixp46x, "intel,ixp46x-interrupt", + ixp4xx_of_init_irq); +#endif |