[PATCH v8 08/10] irqchip: Add Sunplus SP7021 interrupt controller driver

From: Qin Jian
Date: Fri Jan 21 2022 - 02:58:26 EST


Add interrupt controller driver for Sunplus SP7021 SoC.

This is the interrupt controller in P-chip which collects all interrupt
sources in P-chip and routes them to parent interrupt controller in C-chip.

Signed-off-by: Qin Jian <qinjian@xxxxxxxxxxx>
---
Fix the comments from Marc.
---
MAINTAINERS | 1 +
drivers/irqchip/Kconfig | 9 +
drivers/irqchip/Makefile | 1 +
drivers/irqchip/irq-sp7021-intc.c | 288 ++++++++++++++++++++++++++++++
4 files changed, 299 insertions(+)
create mode 100644 drivers/irqchip/irq-sp7021-intc.c

diff --git a/MAINTAINERS b/MAINTAINERS
index 6b3bbe021..febbd97bf 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -2665,6 +2665,7 @@ F: Documentation/devicetree/bindings/clock/sunplus,sp7021-clkc.yaml
F: Documentation/devicetree/bindings/interrupt-controller/sunplus,sp7021-intc.yaml
F: Documentation/devicetree/bindings/reset/sunplus,reset.yaml
F: drivers/clk/clk-sp7021.c
+F: drivers/irqchip/irq-sp7021-intc.c
F: drivers/reset/reset-sunplus.c
F: include/dt-bindings/clock/sp-sp7021.h
F: include/dt-bindings/reset/sp-sp7021.h
diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig
index aca7b595c..32d7a8e0c 100644
--- a/drivers/irqchip/Kconfig
+++ b/drivers/irqchip/Kconfig
@@ -602,4 +602,13 @@ config APPLE_AIC
Support for the Apple Interrupt Controller found on Apple Silicon SoCs,
such as the M1.

+config SUNPLUS_SP7021_INTC
+ bool "Sunplus SP7021 interrupt controller" if COMPILE_TEST
+ default SOC_SP7021
+ help
+ Support for the Sunplus SP7021 Interrupt Controller IP core.
+ SP7021 SoC has 2 Chips: C-Chip & P-Chip. This is used as a
+ chained controller, routing all interrupt source in P-Chip to
+ the primary controller on C-Chip.
+
endmenu
diff --git a/drivers/irqchip/Makefile b/drivers/irqchip/Makefile
index f88cbf36a..75411f654 100644
--- a/drivers/irqchip/Makefile
+++ b/drivers/irqchip/Makefile
@@ -116,3 +116,4 @@ obj-$(CONFIG_MACH_REALTEK_RTL) += irq-realtek-rtl.o
obj-$(CONFIG_WPCM450_AIC) += irq-wpcm450-aic.o
obj-$(CONFIG_IRQ_IDT3243X) += irq-idt3243x.o
obj-$(CONFIG_APPLE_AIC) += irq-apple-aic.o
+obj-$(CONFIG_SUNPLUS_SP7021_INTC) += irq-sp7021-intc.o
diff --git a/drivers/irqchip/irq-sp7021-intc.c b/drivers/irqchip/irq-sp7021-intc.c
new file mode 100644
index 000000000..d1821a955
--- /dev/null
+++ b/drivers/irqchip/irq-sp7021-intc.c
@@ -0,0 +1,288 @@
+// 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 = (int)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);
+}
+
+#ifdef CONFIG_SMP
+static int sp_intc_set_affinity(struct irq_data *d, const struct cpumask *mask, bool force)
+{
+ return -EINVAL;
+}
+#endif
+
+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,
+#ifdef CONFIG_SMP
+ .irq_set_affinity = sp_intc_set_affinity,
+#endif
+};
+
+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 *)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);
--
2.33.1