diff options
Diffstat (limited to 'drivers/irqchip/irq-loongson-liointc.c')
| -rw-r--r-- | drivers/irqchip/irq-loongson-liointc.c | 261 |
1 files changed, 261 insertions, 0 deletions
diff --git a/drivers/irqchip/irq-loongson-liointc.c b/drivers/irqchip/irq-loongson-liointc.c new file mode 100644 index 000000000000..18de2c09ece4 --- /dev/null +++ b/drivers/irqchip/irq-loongson-liointc.c @@ -0,0 +1,261 @@ +// 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> + +#include <boot_param.h> + +#define LIOINTC_CHIP_IRQ 32 +#define LIOINTC_NUM_PARENT 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 + +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]; + u8 map_cache[LIOINTC_CHIP_IRQ]; +}; + +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; + u32 pending; + + chained_irq_enter(chip, desc); + + pending = readl(gc->reg_base + LIOINTC_REG_INTC_STATUS); + + if (!pending) + spurious_interrupt(); + + while (pending) { + int bit = __ffs(pending); + + generic_handle_irq(irq_find_mapping(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: + 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); + /* Revert map cache */ + for (i = 0; i < LIOINTC_CHIP_IRQ; i++) + writeb(priv->map_cache[i], gc->reg_base + i); + /* Revert mask cache */ + writel(~gc->mask_cache, gc->reg_base + LIOINTC_REG_INTC_ENABLE); + irq_gc_unlock_irqrestore(gc, flags); +} + +static const char * const parent_names[] = {"int0", "int1", "int2", "int3"}; + +int __init liointc_of_init(struct device_node *node, + struct device_node *parent) +{ + struct irq_chip_generic *gc; + struct irq_domain *domain; + struct irq_chip_type *ct; + struct liointc_priv *priv; + void __iomem *base; + u32 of_parent_int_map[LIOINTC_NUM_PARENT]; + int parent_irq[LIOINTC_NUM_PARENT]; + bool have_parent = FALSE; + int sz, i, err = 0; + + priv = kzalloc(sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + base = of_iomap(node, 0); + if (!base) { + err = -ENODEV; + goto out_free_priv; + } + + 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) { + err = -ENODEV; + goto out_iounmap; + } + + sz = of_property_read_variable_u32_array(node, + "loongson,parent_int_map", + &of_parent_int_map[0], + LIOINTC_NUM_PARENT, + LIOINTC_NUM_PARENT); + if (sz < 4) { + pr_err("loongson-liointc: No parent_int_map\n"); + err = -ENODEV; + goto out_iounmap; + } + + for (i = 0; i < LIOINTC_NUM_PARENT; i++) + priv->handler[i].parent_int_map = of_parent_int_map[i]; + + /* Setup IRQ domain */ + domain = irq_domain_add_linear(node, 32, + &irq_generic_chip_ops, priv); + if (!domain) { + pr_err("loongson-liointc: cannot add IRQ domain\n"); + err = -EINVAL; + goto out_iounmap; + } + + err = irq_alloc_domain_generic_chips(domain, 32, 1, + node->full_name, handle_level_irq, + IRQ_NOPROBE, 0, 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 = 0xffffffff; + 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]); + } + + return 0; + +out_free_domain: + irq_domain_remove(domain); +out_iounmap: + iounmap(base); +out_free_priv: + kfree(priv); + + return err; +} + +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); |