diff options
Diffstat (limited to 'drivers/irqchip/irq-sp7021-intc.c')
| -rw-r--r-- | drivers/irqchip/irq-sp7021-intc.c | 278 |
1 files changed, 278 insertions, 0 deletions
diff --git a/drivers/irqchip/irq-sp7021-intc.c b/drivers/irqchip/irq-sp7021-intc.c new file mode 100644 index 000000000000..bed78d1def3d --- /dev/null +++ b/drivers/irqchip/irq-sp7021-intc.c @@ -0,0 +1,278 @@ +// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +/* + * Copyright (C) Sunplus Technology Co., Ltd. + * All rights reserved. + */ +#include <linux/irq.h> +#include <linux/irqdomain.h> +#include <linux/io.h> +#include <linux/irqchip.h> +#include <linux/irqchip/chained_irq.h> +#include <linux/of_address.h> +#include <linux/of_irq.h> + +#define SP_INTC_HWIRQ_MIN 0 +#define SP_INTC_HWIRQ_MAX 223 + +#define SP_INTC_NR_IRQS (SP_INTC_HWIRQ_MAX - SP_INTC_HWIRQ_MIN + 1) +#define SP_INTC_NR_GROUPS DIV_ROUND_UP(SP_INTC_NR_IRQS, 32) +#define SP_INTC_REG_SIZE (SP_INTC_NR_GROUPS * 4) + +/* REG_GROUP_0 regs */ +#define REG_INTR_TYPE (sp_intc.g0) +#define REG_INTR_POLARITY (REG_INTR_TYPE + SP_INTC_REG_SIZE) +#define REG_INTR_PRIORITY (REG_INTR_POLARITY + SP_INTC_REG_SIZE) +#define REG_INTR_MASK (REG_INTR_PRIORITY + SP_INTC_REG_SIZE) + +/* REG_GROUP_1 regs */ +#define REG_INTR_CLEAR (sp_intc.g1) +#define REG_MASKED_EXT1 (REG_INTR_CLEAR + SP_INTC_REG_SIZE) +#define REG_MASKED_EXT0 (REG_MASKED_EXT1 + SP_INTC_REG_SIZE) +#define REG_INTR_GROUP (REG_INTR_CLEAR + 31 * 4) + +#define GROUP_MASK (BIT(SP_INTC_NR_GROUPS) - 1) +#define GROUP_SHIFT_EXT1 (0) +#define GROUP_SHIFT_EXT0 (8) + +/* + * When GPIO_INT0~7 set to edge trigger, doesn't work properly. + * WORKAROUND: change it to level trigger, and toggle the polarity + * at ACK/Handler to make the HW work. + */ +#define GPIO_INT0_HWIRQ 120 +#define GPIO_INT7_HWIRQ 127 +#define IS_GPIO_INT(irq) \ +({ \ + u32 i = irq; \ + (i >= GPIO_INT0_HWIRQ) && (i <= GPIO_INT7_HWIRQ); \ +}) + +/* index of states */ +enum { + _IS_EDGE = 0, + _IS_LOW, + _IS_ACTIVE +}; + +#define STATE_BIT(irq, idx) (((irq) - GPIO_INT0_HWIRQ) * 3 + (idx)) +#define ASSIGN_STATE(irq, idx, v) assign_bit(STATE_BIT(irq, idx), sp_intc.states, v) +#define TEST_STATE(irq, idx) test_bit(STATE_BIT(irq, idx), sp_intc.states) + +static struct sp_intctl { + /* + * REG_GROUP_0: include type/polarity/priority/mask regs. + * REG_GROUP_1: include clear/masked_ext0/masked_ext1/group regs. + */ + void __iomem *g0; // REG_GROUP_0 base + void __iomem *g1; // REG_GROUP_1 base + + struct irq_domain *domain; + raw_spinlock_t lock; + + /* + * store GPIO_INT states + * each interrupt has 3 states: is_edge, is_low, is_active + */ + DECLARE_BITMAP(states, (GPIO_INT7_HWIRQ - GPIO_INT0_HWIRQ + 1) * 3); +} sp_intc; + +static struct irq_chip sp_intc_chip; + +static void sp_intc_assign_bit(u32 hwirq, void __iomem *base, bool value) +{ + u32 offset, mask; + unsigned long flags; + void __iomem *reg; + + offset = (hwirq / 32) * 4; + reg = base + offset; + + raw_spin_lock_irqsave(&sp_intc.lock, flags); + mask = readl_relaxed(reg); + if (value) + mask |= BIT(hwirq % 32); + else + mask &= ~BIT(hwirq % 32); + writel_relaxed(mask, reg); + raw_spin_unlock_irqrestore(&sp_intc.lock, flags); +} + +static void sp_intc_ack_irq(struct irq_data *d) +{ + u32 hwirq = d->hwirq; + + if (unlikely(IS_GPIO_INT(hwirq) && TEST_STATE(hwirq, _IS_EDGE))) { // WORKAROUND + sp_intc_assign_bit(hwirq, REG_INTR_POLARITY, !TEST_STATE(hwirq, _IS_LOW)); + ASSIGN_STATE(hwirq, _IS_ACTIVE, true); + } + + sp_intc_assign_bit(hwirq, REG_INTR_CLEAR, 1); +} + +static void sp_intc_mask_irq(struct irq_data *d) +{ + sp_intc_assign_bit(d->hwirq, REG_INTR_MASK, 0); +} + +static void sp_intc_unmask_irq(struct irq_data *d) +{ + sp_intc_assign_bit(d->hwirq, REG_INTR_MASK, 1); +} + +static int sp_intc_set_type(struct irq_data *d, unsigned int type) +{ + u32 hwirq = d->hwirq; + bool is_edge = !(type & IRQ_TYPE_LEVEL_MASK); + bool is_low = (type == IRQ_TYPE_LEVEL_LOW || type == IRQ_TYPE_EDGE_FALLING); + + irq_set_handler_locked(d, is_edge ? handle_edge_irq : handle_level_irq); + + if (unlikely(IS_GPIO_INT(hwirq) && is_edge)) { // WORKAROUND + /* store states */ + ASSIGN_STATE(hwirq, _IS_EDGE, is_edge); + ASSIGN_STATE(hwirq, _IS_LOW, is_low); + ASSIGN_STATE(hwirq, _IS_ACTIVE, false); + /* change to level */ + is_edge = false; + } + + sp_intc_assign_bit(hwirq, REG_INTR_TYPE, is_edge); + sp_intc_assign_bit(hwirq, REG_INTR_POLARITY, is_low); + + return 0; +} + +static int sp_intc_get_ext_irq(int ext_num) +{ + void __iomem *base = ext_num ? REG_MASKED_EXT1 : REG_MASKED_EXT0; + u32 shift = ext_num ? GROUP_SHIFT_EXT1 : GROUP_SHIFT_EXT0; + u32 groups; + u32 pending_group; + u32 group; + u32 pending_irq; + + groups = readl_relaxed(REG_INTR_GROUP); + pending_group = (groups >> shift) & GROUP_MASK; + if (!pending_group) + return -1; + + group = fls(pending_group) - 1; + pending_irq = readl_relaxed(base + group * 4); + if (!pending_irq) + return -1; + + return (group * 32) + fls(pending_irq) - 1; +} + +static void sp_intc_handle_ext_cascaded(struct irq_desc *desc) +{ + struct irq_chip *chip = irq_desc_get_chip(desc); + int ext_num = (uintptr_t)irq_desc_get_handler_data(desc); + int hwirq; + + chained_irq_enter(chip, desc); + + while ((hwirq = sp_intc_get_ext_irq(ext_num)) >= 0) { + if (unlikely(IS_GPIO_INT(hwirq) && TEST_STATE(hwirq, _IS_ACTIVE))) { // WORKAROUND + ASSIGN_STATE(hwirq, _IS_ACTIVE, false); + sp_intc_assign_bit(hwirq, REG_INTR_POLARITY, TEST_STATE(hwirq, _IS_LOW)); + } else { + generic_handle_domain_irq(sp_intc.domain, hwirq); + } + } + + chained_irq_exit(chip, desc); +} + +static struct irq_chip sp_intc_chip = { + .name = "sp_intc", + .irq_ack = sp_intc_ack_irq, + .irq_mask = sp_intc_mask_irq, + .irq_unmask = sp_intc_unmask_irq, + .irq_set_type = sp_intc_set_type, +}; + +static int sp_intc_irq_domain_map(struct irq_domain *domain, + unsigned int irq, irq_hw_number_t hwirq) +{ + irq_set_chip_and_handler(irq, &sp_intc_chip, handle_level_irq); + irq_set_chip_data(irq, &sp_intc_chip); + irq_set_noprobe(irq); + + return 0; +} + +static const struct irq_domain_ops sp_intc_dm_ops = { + .xlate = irq_domain_xlate_twocell, + .map = sp_intc_irq_domain_map, +}; + +static int sp_intc_irq_map(struct device_node *node, int i) +{ + unsigned int irq; + + irq = irq_of_parse_and_map(node, i); + if (!irq) + return -ENOENT; + + irq_set_chained_handler_and_data(irq, sp_intc_handle_ext_cascaded, (void *)(uintptr_t)i); + + return 0; +} + +static int __init sp_intc_init_dt(struct device_node *node, struct device_node *parent) +{ + int i, ret; + + sp_intc.g0 = of_iomap(node, 0); + if (!sp_intc.g0) + return -ENXIO; + + sp_intc.g1 = of_iomap(node, 1); + if (!sp_intc.g1) { + ret = -ENXIO; + goto out_unmap0; + } + + ret = sp_intc_irq_map(node, 0); // EXT_INT0 + if (ret) + goto out_unmap1; + + ret = sp_intc_irq_map(node, 1); // EXT_INT1 + if (ret) + goto out_unmap1; + + /* initial regs */ + for (i = 0; i < SP_INTC_NR_GROUPS; i++) { + /* all mask */ + writel_relaxed(0, REG_INTR_MASK + i * 4); + /* all edge */ + writel_relaxed(~0, REG_INTR_TYPE + i * 4); + /* all high-active */ + writel_relaxed(0, REG_INTR_POLARITY + i * 4); + /* all EXT_INT0 */ + writel_relaxed(~0, REG_INTR_PRIORITY + i * 4); + /* all clear */ + writel_relaxed(~0, REG_INTR_CLEAR + i * 4); + } + + sp_intc.domain = irq_domain_add_linear(node, SP_INTC_NR_IRQS, + &sp_intc_dm_ops, &sp_intc); + if (!sp_intc.domain) { + ret = -ENOMEM; + goto out_unmap1; + } + + raw_spin_lock_init(&sp_intc.lock); + + return 0; + +out_unmap1: + iounmap(sp_intc.g1); +out_unmap0: + iounmap(sp_intc.g0); + + return ret; +} + +IRQCHIP_DECLARE(sp_intc, "sunplus,sp7021-intc", sp_intc_init_dt); |