diff options
Diffstat (limited to 'drivers/irqchip/irq-loongson-liointc.c')
| -rw-r--r-- | drivers/irqchip/irq-loongson-liointc.c | 378 |
1 files changed, 378 insertions, 0 deletions
diff --git a/drivers/irqchip/irq-loongson-liointc.c b/drivers/irqchip/irq-loongson-liointc.c new file mode 100644 index 000000000..c4584e2f0 --- /dev/null +++ b/drivers/irqchip/irq-loongson-liointc.c @@ -0,0 +1,378 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2020, Jiaxun Yang <jiaxun.yang@flygoat.com> + * Loongson Local IO Interrupt Controller support + */ + +#include <linux/errno.h> +#include <linux/init.h> +#include <linux/types.h> +#include <linux/interrupt.h> +#include <linux/ioport.h> +#include <linux/irqchip.h> +#include <linux/of_address.h> +#include <linux/of_irq.h> +#include <linux/io.h> +#include <linux/smp.h> +#include <linux/irqchip/chained_irq.h> + +#ifdef CONFIG_MIPS +#include <loongson.h> +#else +#include <asm/loongson.h> +#endif + +#define LIOINTC_CHIP_IRQ 32 +#define LIOINTC_NUM_PARENT 4 +#define LIOINTC_NUM_CORES 4 + +#define LIOINTC_INTC_CHIP_START 0x20 + +#define LIOINTC_REG_INTC_STATUS (LIOINTC_INTC_CHIP_START + 0x20) +#define LIOINTC_REG_INTC_EN_STATUS (LIOINTC_INTC_CHIP_START + 0x04) +#define LIOINTC_REG_INTC_ENABLE (LIOINTC_INTC_CHIP_START + 0x08) +#define LIOINTC_REG_INTC_DISABLE (LIOINTC_INTC_CHIP_START + 0x0c) +#define LIOINTC_REG_INTC_POL (LIOINTC_INTC_CHIP_START + 0x10) +#define LIOINTC_REG_INTC_EDGE (LIOINTC_INTC_CHIP_START + 0x14) + +#define LIOINTC_SHIFT_INTx 4 + +#define LIOINTC_ERRATA_IRQ 10 + +#if defined(CONFIG_MIPS) +#define liointc_core_id get_ebase_cpunum() +#else +#define liointc_core_id get_csr_cpuid() +#endif + +struct liointc_handler_data { + struct liointc_priv *priv; + u32 parent_int_map; +}; + +struct liointc_priv { + struct irq_chip_generic *gc; + struct liointc_handler_data handler[LIOINTC_NUM_PARENT]; + void __iomem *core_isr[LIOINTC_NUM_CORES]; + u8 map_cache[LIOINTC_CHIP_IRQ]; + bool has_lpc_irq_errata; +}; + +struct fwnode_handle *liointc_handle; + +static void liointc_chained_handle_irq(struct irq_desc *desc) +{ + struct liointc_handler_data *handler = irq_desc_get_handler_data(desc); + struct irq_chip *chip = irq_desc_get_chip(desc); + struct irq_chip_generic *gc = handler->priv->gc; + int core = liointc_core_id % LIOINTC_NUM_CORES; + u32 pending; + + chained_irq_enter(chip, desc); + + pending = readl(handler->priv->core_isr[core]); + + if (!pending) { + /* Always blame LPC IRQ if we have that bug */ + if (handler->priv->has_lpc_irq_errata && + (handler->parent_int_map & gc->mask_cache & + BIT(LIOINTC_ERRATA_IRQ))) + pending = BIT(LIOINTC_ERRATA_IRQ); + else + spurious_interrupt(); + } + + while (pending) { + int bit = __ffs(pending); + + generic_handle_domain_irq(gc->domain, bit); + pending &= ~BIT(bit); + } + + chained_irq_exit(chip, desc); +} + +static void liointc_set_bit(struct irq_chip_generic *gc, + unsigned int offset, + u32 mask, bool set) +{ + if (set) + writel(readl(gc->reg_base + offset) | mask, + gc->reg_base + offset); + else + writel(readl(gc->reg_base + offset) & ~mask, + gc->reg_base + offset); +} + +static int liointc_set_type(struct irq_data *data, unsigned int type) +{ + struct irq_chip_generic *gc = irq_data_get_irq_chip_data(data); + u32 mask = data->mask; + unsigned long flags; + + irq_gc_lock_irqsave(gc, flags); + switch (type) { + case IRQ_TYPE_LEVEL_HIGH: + liointc_set_bit(gc, LIOINTC_REG_INTC_EDGE, mask, false); + liointc_set_bit(gc, LIOINTC_REG_INTC_POL, mask, true); + break; + case IRQ_TYPE_LEVEL_LOW: + liointc_set_bit(gc, LIOINTC_REG_INTC_EDGE, mask, false); + liointc_set_bit(gc, LIOINTC_REG_INTC_POL, mask, false); + break; + case IRQ_TYPE_EDGE_RISING: + liointc_set_bit(gc, LIOINTC_REG_INTC_EDGE, mask, true); + liointc_set_bit(gc, LIOINTC_REG_INTC_POL, mask, true); + break; + case IRQ_TYPE_EDGE_FALLING: + liointc_set_bit(gc, LIOINTC_REG_INTC_EDGE, mask, true); + liointc_set_bit(gc, LIOINTC_REG_INTC_POL, mask, false); + break; + default: + irq_gc_unlock_irqrestore(gc, flags); + return -EINVAL; + } + irq_gc_unlock_irqrestore(gc, flags); + + irqd_set_trigger_type(data, type); + return 0; +} + +static void liointc_resume(struct irq_chip_generic *gc) +{ + struct liointc_priv *priv = gc->private; + unsigned long flags; + int i; + + irq_gc_lock_irqsave(gc, flags); + /* Disable all at first */ + writel(0xffffffff, gc->reg_base + LIOINTC_REG_INTC_DISABLE); + /* Restore map cache */ + for (i = 0; i < LIOINTC_CHIP_IRQ; i++) + writeb(priv->map_cache[i], gc->reg_base + i); + /* Restore mask cache */ + writel(gc->mask_cache, gc->reg_base + LIOINTC_REG_INTC_ENABLE); + irq_gc_unlock_irqrestore(gc, flags); +} + +static int parent_irq[LIOINTC_NUM_PARENT]; +static u32 parent_int_map[LIOINTC_NUM_PARENT]; +static const char *const parent_names[] = {"int0", "int1", "int2", "int3"}; +static const char *const core_reg_names[] = {"isr0", "isr1", "isr2", "isr3"}; + +static int liointc_domain_xlate(struct irq_domain *d, struct device_node *ctrlr, + const u32 *intspec, unsigned int intsize, + unsigned long *out_hwirq, unsigned int *out_type) +{ + if (WARN_ON(intsize < 1)) + return -EINVAL; + *out_hwirq = intspec[0] - GSI_MIN_CPU_IRQ; + *out_type = IRQ_TYPE_NONE; + return 0; +} + +static const struct irq_domain_ops acpi_irq_gc_ops = { + .map = irq_map_generic_chip, + .unmap = irq_unmap_generic_chip, + .xlate = liointc_domain_xlate, +}; + +static int liointc_init(phys_addr_t addr, unsigned long size, int revision, + struct fwnode_handle *domain_handle, struct device_node *node) +{ + int i, err; + void __iomem *base; + struct irq_chip_type *ct; + struct irq_chip_generic *gc; + struct irq_domain *domain; + struct liointc_priv *priv; + + priv = kzalloc(sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + base = ioremap(addr, size); + if (!base) + goto out_free_priv; + + for (i = 0; i < LIOINTC_NUM_CORES; i++) + priv->core_isr[i] = base + LIOINTC_REG_INTC_STATUS; + + for (i = 0; i < LIOINTC_NUM_PARENT; i++) + priv->handler[i].parent_int_map = parent_int_map[i]; + + if (revision > 1) { + for (i = 0; i < LIOINTC_NUM_CORES; i++) { + int index = of_property_match_string(node, + "reg-names", core_reg_names[i]); + + if (index < 0) + continue; + + priv->core_isr[i] = of_iomap(node, index); + } + + if (!priv->core_isr[0]) + goto out_iounmap; + } + + /* Setup IRQ domain */ + if (!acpi_disabled) + domain = irq_domain_create_linear(domain_handle, LIOINTC_CHIP_IRQ, + &acpi_irq_gc_ops, priv); + else + domain = irq_domain_create_linear(domain_handle, LIOINTC_CHIP_IRQ, + &irq_generic_chip_ops, priv); + if (!domain) { + pr_err("loongson-liointc: cannot add IRQ domain\n"); + goto out_iounmap; + } + + err = irq_alloc_domain_generic_chips(domain, LIOINTC_CHIP_IRQ, 1, + (node ? node->full_name : "LIOINTC"), + handle_level_irq, 0, IRQ_NOPROBE, 0); + if (err) { + pr_err("loongson-liointc: unable to register IRQ domain\n"); + goto out_free_domain; + } + + + /* Disable all IRQs */ + writel(0xffffffff, base + LIOINTC_REG_INTC_DISABLE); + /* Set to level triggered */ + writel(0x0, base + LIOINTC_REG_INTC_EDGE); + + /* Generate parent INT part of map cache */ + for (i = 0; i < LIOINTC_NUM_PARENT; i++) { + u32 pending = priv->handler[i].parent_int_map; + + while (pending) { + int bit = __ffs(pending); + + priv->map_cache[bit] = BIT(i) << LIOINTC_SHIFT_INTx; + pending &= ~BIT(bit); + } + } + + for (i = 0; i < LIOINTC_CHIP_IRQ; i++) { + /* Generate core part of map cache */ + priv->map_cache[i] |= BIT(loongson_sysconf.boot_cpu_id); + writeb(priv->map_cache[i], base + i); + } + + gc = irq_get_domain_generic_chip(domain, 0); + gc->private = priv; + gc->reg_base = base; + gc->domain = domain; + gc->resume = liointc_resume; + + ct = gc->chip_types; + ct->regs.enable = LIOINTC_REG_INTC_ENABLE; + ct->regs.disable = LIOINTC_REG_INTC_DISABLE; + ct->chip.irq_unmask = irq_gc_unmask_enable_reg; + ct->chip.irq_mask = irq_gc_mask_disable_reg; + ct->chip.irq_mask_ack = irq_gc_mask_disable_reg; + ct->chip.irq_set_type = liointc_set_type; + + gc->mask_cache = 0; + priv->gc = gc; + + for (i = 0; i < LIOINTC_NUM_PARENT; i++) { + if (parent_irq[i] <= 0) + continue; + + priv->handler[i].priv = priv; + irq_set_chained_handler_and_data(parent_irq[i], + liointc_chained_handle_irq, &priv->handler[i]); + } + + liointc_handle = domain_handle; + return 0; + +out_free_domain: + irq_domain_remove(domain); +out_iounmap: + iounmap(base); +out_free_priv: + kfree(priv); + + return -EINVAL; +} + +#ifdef CONFIG_OF + +static int __init liointc_of_init(struct device_node *node, + struct device_node *parent) +{ + bool have_parent = FALSE; + int sz, i, index, revision, err = 0; + struct resource res; + + if (!of_device_is_compatible(node, "loongson,liointc-2.0")) { + index = 0; + revision = 1; + } else { + index = of_property_match_string(node, "reg-names", "main"); + revision = 2; + } + + if (of_address_to_resource(node, index, &res)) + return -EINVAL; + + for (i = 0; i < LIOINTC_NUM_PARENT; i++) { + parent_irq[i] = of_irq_get_byname(node, parent_names[i]); + if (parent_irq[i] > 0) + have_parent = TRUE; + } + if (!have_parent) + return -ENODEV; + + sz = of_property_read_variable_u32_array(node, + "loongson,parent_int_map", + &parent_int_map[0], + LIOINTC_NUM_PARENT, + LIOINTC_NUM_PARENT); + if (sz < 4) { + pr_err("loongson-liointc: No parent_int_map\n"); + return -ENODEV; + } + + err = liointc_init(res.start, resource_size(&res), + revision, of_node_to_fwnode(node), node); + if (err < 0) + return err; + + return 0; +} + +IRQCHIP_DECLARE(loongson_liointc_1_0, "loongson,liointc-1.0", liointc_of_init); +IRQCHIP_DECLARE(loongson_liointc_1_0a, "loongson,liointc-1.0a", liointc_of_init); +IRQCHIP_DECLARE(loongson_liointc_2_0, "loongson,liointc-2.0", liointc_of_init); + +#endif + +#ifdef CONFIG_ACPI +int __init liointc_acpi_init(struct irq_domain *parent, struct acpi_madt_lio_pic *acpi_liointc) +{ + int ret; + struct fwnode_handle *domain_handle; + + parent_int_map[0] = acpi_liointc->cascade_map[0]; + parent_int_map[1] = acpi_liointc->cascade_map[1]; + + parent_irq[0] = irq_create_mapping(parent, acpi_liointc->cascade[0]); + parent_irq[1] = irq_create_mapping(parent, acpi_liointc->cascade[1]); + + domain_handle = irq_domain_alloc_fwnode(&acpi_liointc->address); + if (!domain_handle) { + pr_err("Unable to allocate domain handle\n"); + return -ENOMEM; + } + ret = liointc_init(acpi_liointc->address, acpi_liointc->size, + 1, domain_handle, NULL); + if (ret) + irq_domain_free_fwnode(domain_handle); + + return ret; +} +#endif |