diff options
Diffstat (limited to 'drivers/irqchip/irq-davinci-cp-intc.c')
| -rw-r--r-- | drivers/irqchip/irq-davinci-cp-intc.c | 260 |
1 files changed, 260 insertions, 0 deletions
diff --git a/drivers/irqchip/irq-davinci-cp-intc.c b/drivers/irqchip/irq-davinci-cp-intc.c new file mode 100644 index 000000000..7482c8ed3 --- /dev/null +++ b/drivers/irqchip/irq-davinci-cp-intc.c @@ -0,0 +1,260 @@ +// SPDX-License-Identifier: GPL-2.0-only +// +// Author: Steve Chen <schen@mvista.com> +// Copyright (C) 2008-2009, MontaVista Software, Inc. <source@mvista.com> +// Author: Bartosz Golaszewski <bgolaszewski@baylibre.com> +// Copyright (C) 2019, Texas Instruments +// +// TI Common Platform Interrupt Controller (cp_intc) driver + +#include <linux/export.h> +#include <linux/init.h> +#include <linux/irq.h> +#include <linux/irqchip.h> +#include <linux/irqchip/irq-davinci-cp-intc.h> +#include <linux/irqdomain.h> +#include <linux/io.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/of_irq.h> + +#include <asm/exception.h> + +#define DAVINCI_CP_INTC_CTRL 0x04 +#define DAVINCI_CP_INTC_HOST_CTRL 0x0c +#define DAVINCI_CP_INTC_GLOBAL_ENABLE 0x10 +#define DAVINCI_CP_INTC_SYS_STAT_IDX_CLR 0x24 +#define DAVINCI_CP_INTC_SYS_ENABLE_IDX_SET 0x28 +#define DAVINCI_CP_INTC_SYS_ENABLE_IDX_CLR 0x2c +#define DAVINCI_CP_INTC_HOST_ENABLE_IDX_SET 0x34 +#define DAVINCI_CP_INTC_HOST_ENABLE_IDX_CLR 0x38 +#define DAVINCI_CP_INTC_PRIO_IDX 0x80 +#define DAVINCI_CP_INTC_SYS_STAT_CLR(n) (0x0280 + (n << 2)) +#define DAVINCI_CP_INTC_SYS_ENABLE_CLR(n) (0x0380 + (n << 2)) +#define DAVINCI_CP_INTC_CHAN_MAP(n) (0x0400 + (n << 2)) +#define DAVINCI_CP_INTC_SYS_POLARITY(n) (0x0d00 + (n << 2)) +#define DAVINCI_CP_INTC_SYS_TYPE(n) (0x0d80 + (n << 2)) +#define DAVINCI_CP_INTC_HOST_ENABLE(n) (0x1500 + (n << 2)) +#define DAVINCI_CP_INTC_PRI_INDX_MASK GENMASK(9, 0) +#define DAVINCI_CP_INTC_GPIR_NONE BIT(31) + +static void __iomem *davinci_cp_intc_base; +static struct irq_domain *davinci_cp_intc_irq_domain; + +static inline unsigned int davinci_cp_intc_read(unsigned int offset) +{ + return readl_relaxed(davinci_cp_intc_base + offset); +} + +static inline void davinci_cp_intc_write(unsigned long value, + unsigned int offset) +{ + writel_relaxed(value, davinci_cp_intc_base + offset); +} + +static void davinci_cp_intc_ack_irq(struct irq_data *d) +{ + davinci_cp_intc_write(d->hwirq, DAVINCI_CP_INTC_SYS_STAT_IDX_CLR); +} + +static void davinci_cp_intc_mask_irq(struct irq_data *d) +{ + /* XXX don't know why we need to disable nIRQ here... */ + davinci_cp_intc_write(1, DAVINCI_CP_INTC_HOST_ENABLE_IDX_CLR); + davinci_cp_intc_write(d->hwirq, DAVINCI_CP_INTC_SYS_ENABLE_IDX_CLR); + davinci_cp_intc_write(1, DAVINCI_CP_INTC_HOST_ENABLE_IDX_SET); +} + +static void davinci_cp_intc_unmask_irq(struct irq_data *d) +{ + davinci_cp_intc_write(d->hwirq, DAVINCI_CP_INTC_SYS_ENABLE_IDX_SET); +} + +static int davinci_cp_intc_set_irq_type(struct irq_data *d, + unsigned int flow_type) +{ + unsigned int reg, mask, polarity, type; + + reg = BIT_WORD(d->hwirq); + mask = BIT_MASK(d->hwirq); + polarity = davinci_cp_intc_read(DAVINCI_CP_INTC_SYS_POLARITY(reg)); + type = davinci_cp_intc_read(DAVINCI_CP_INTC_SYS_TYPE(reg)); + + switch (flow_type) { + case IRQ_TYPE_EDGE_RISING: + polarity |= mask; + type |= mask; + break; + case IRQ_TYPE_EDGE_FALLING: + polarity &= ~mask; + type |= mask; + break; + case IRQ_TYPE_LEVEL_HIGH: + polarity |= mask; + type &= ~mask; + break; + case IRQ_TYPE_LEVEL_LOW: + polarity &= ~mask; + type &= ~mask; + break; + default: + return -EINVAL; + } + + davinci_cp_intc_write(polarity, DAVINCI_CP_INTC_SYS_POLARITY(reg)); + davinci_cp_intc_write(type, DAVINCI_CP_INTC_SYS_TYPE(reg)); + + return 0; +} + +static struct irq_chip davinci_cp_intc_irq_chip = { + .name = "cp_intc", + .irq_ack = davinci_cp_intc_ack_irq, + .irq_mask = davinci_cp_intc_mask_irq, + .irq_unmask = davinci_cp_intc_unmask_irq, + .irq_set_type = davinci_cp_intc_set_irq_type, + .flags = IRQCHIP_SKIP_SET_WAKE, +}; + +static asmlinkage void __exception_irq_entry +davinci_cp_intc_handle_irq(struct pt_regs *regs) +{ + int gpir, irqnr, none; + + /* + * The interrupt number is in first ten bits. The NONE field set to 1 + * indicates a spurious irq. + */ + + gpir = davinci_cp_intc_read(DAVINCI_CP_INTC_PRIO_IDX); + irqnr = gpir & DAVINCI_CP_INTC_PRI_INDX_MASK; + none = gpir & DAVINCI_CP_INTC_GPIR_NONE; + + if (unlikely(none)) { + pr_err_once("%s: spurious irq!\n", __func__); + return; + } + + generic_handle_domain_irq(davinci_cp_intc_irq_domain, irqnr); +} + +static int davinci_cp_intc_host_map(struct irq_domain *h, unsigned int virq, + irq_hw_number_t hw) +{ + pr_debug("cp_intc_host_map(%d, 0x%lx)\n", virq, hw); + + irq_set_chip(virq, &davinci_cp_intc_irq_chip); + irq_set_probe(virq); + irq_set_handler(virq, handle_edge_irq); + + return 0; +} + +static const struct irq_domain_ops davinci_cp_intc_irq_domain_ops = { + .map = davinci_cp_intc_host_map, + .xlate = irq_domain_xlate_onetwocell, +}; + +static int __init +davinci_cp_intc_do_init(const struct davinci_cp_intc_config *config, + struct device_node *node) +{ + unsigned int num_regs = BITS_TO_LONGS(config->num_irqs); + int offset, irq_base; + void __iomem *req; + + req = request_mem_region(config->reg.start, + resource_size(&config->reg), + "davinci-cp-intc"); + if (!req) { + pr_err("%s: register range busy\n", __func__); + return -EBUSY; + } + + davinci_cp_intc_base = ioremap(config->reg.start, + resource_size(&config->reg)); + if (!davinci_cp_intc_base) { + pr_err("%s: unable to ioremap register range\n", __func__); + return -EINVAL; + } + + davinci_cp_intc_write(0, DAVINCI_CP_INTC_GLOBAL_ENABLE); + + /* Disable all host interrupts */ + davinci_cp_intc_write(0, DAVINCI_CP_INTC_HOST_ENABLE(0)); + + /* Disable system interrupts */ + for (offset = 0; offset < num_regs; offset++) + davinci_cp_intc_write(~0, + DAVINCI_CP_INTC_SYS_ENABLE_CLR(offset)); + + /* Set to normal mode, no nesting, no priority hold */ + davinci_cp_intc_write(0, DAVINCI_CP_INTC_CTRL); + davinci_cp_intc_write(0, DAVINCI_CP_INTC_HOST_CTRL); + + /* Clear system interrupt status */ + for (offset = 0; offset < num_regs; offset++) + davinci_cp_intc_write(~0, + DAVINCI_CP_INTC_SYS_STAT_CLR(offset)); + + /* Enable nIRQ (what about nFIQ?) */ + davinci_cp_intc_write(1, DAVINCI_CP_INTC_HOST_ENABLE_IDX_SET); + + /* Default all priorities to channel 7. */ + num_regs = (config->num_irqs + 3) >> 2; /* 4 channels per register */ + for (offset = 0; offset < num_regs; offset++) + davinci_cp_intc_write(0x07070707, + DAVINCI_CP_INTC_CHAN_MAP(offset)); + + irq_base = irq_alloc_descs(-1, 0, config->num_irqs, 0); + if (irq_base < 0) { + pr_err("%s: unable to allocate interrupt descriptors: %d\n", + __func__, irq_base); + return irq_base; + } + + davinci_cp_intc_irq_domain = irq_domain_add_legacy( + node, config->num_irqs, irq_base, 0, + &davinci_cp_intc_irq_domain_ops, NULL); + + if (!davinci_cp_intc_irq_domain) { + pr_err("%s: unable to create an interrupt domain\n", __func__); + return -EINVAL; + } + + set_handle_irq(davinci_cp_intc_handle_irq); + + /* Enable global interrupt */ + davinci_cp_intc_write(1, DAVINCI_CP_INTC_GLOBAL_ENABLE); + + return 0; +} + +int __init davinci_cp_intc_init(const struct davinci_cp_intc_config *config) +{ + return davinci_cp_intc_do_init(config, NULL); +} + +static int __init davinci_cp_intc_of_init(struct device_node *node, + struct device_node *parent) +{ + struct davinci_cp_intc_config config = { }; + int ret; + + ret = of_address_to_resource(node, 0, &config.reg); + if (ret) { + pr_err("%s: unable to get the register range from device-tree\n", + __func__); + return ret; + } + + ret = of_property_read_u32(node, "ti,intc-size", &config.num_irqs); + if (ret) { + pr_err("%s: unable to read the 'ti,intc-size' property\n", + __func__); + return ret; + } + + return davinci_cp_intc_do_init(&config, node); +} +IRQCHIP_DECLARE(cp_intc, "ti,cp-intc", davinci_cp_intc_of_init); |