[RFC PATCH v4 2/5] irqchip: Add RZ/G2L IA55 Interrupt Controller driver

Lad Prabhakar
2022-03-17T01:24:26Z

Add a driver for the Renesas RZ/G2L Interrupt Controller.

This supports external pins being used as interrupts. It supports
one line for NMI, 8 external pins and 32 GPIO pins (out of 123)
to be used as IRQ lines.

Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
---
drivers/irqchip/Kconfig | 8 +
drivers/irqchip/Makefile | 1 +
drivers/irqchip/irq-renesas-rzg2l.c | 462 ++++++++++++++++++++++++++++
3 files changed, 471 insertions(+)
create mode 100644 drivers/irqchip/irq-renesas-rzg2l.c

diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig
index 7038957f4a77..afc5999f4955 100644
--- a/drivers/irqchip/Kconfig
+++ b/drivers/irqchip/Kconfig
@@ -242,6 +242,14 @@ config RENESAS_RZA1_IRQC
Enable support for the Renesas RZ/A1 Interrupt Controller, to use up
to 8 external interrupts with configurable sense select.

+config RENESAS_RZG2L_IRQC
+ bool "Renesas RZ/G2L (and alike SoC) IRQC support" if COMPILE_TEST
+ select GENERIC_IRQ_CHIP
+ select IRQ_DOMAIN_HIERARCHY
+ help
+ Enable support for the Renesas RZ/G2L (and alike SoC) Interrupt Controller
+ for external devices.
+
config SL28CPLD_INTC
bool "Kontron sl28cpld IRQ controller"
depends on MFD_SL28CPLD=y || COMPILE_TEST
diff --git a/drivers/irqchip/Makefile b/drivers/irqchip/Makefile
index c1f611cbfbf8..b536e514a7c9 100644
--- a/drivers/irqchip/Makefile
+++ b/drivers/irqchip/Makefile
@@ -51,6 +51,7 @@ obj-$(CONFIG_RDA_INTC) += irq-rda-intc.o
obj-$(CONFIG_RENESAS_INTC_IRQPIN) += irq-renesas-intc-irqpin.o
obj-$(CONFIG_RENESAS_IRQC) += irq-renesas-irqc.o
obj-$(CONFIG_RENESAS_RZA1_IRQC) += irq-renesas-rza1.o
+obj-$(CONFIG_RENESAS_RZG2L_IRQC) += irq-renesas-rzg2l.o
obj-$(CONFIG_VERSATILE_FPGA_IRQ) += irq-versatile-fpga.o
obj-$(CONFIG_ARCH_NSPIRE) += irq-zevio.o
obj-$(CONFIG_ARCH_VT8500) += irq-vt8500.o
diff --git a/drivers/irqchip/irq-renesas-rzg2l.c b/drivers/irqchip/irq-renesas-rzg2l.c
new file mode 100644
index 000000000000..be9741e88bd7
--- /dev/null
+++ b/drivers/irqchip/irq-renesas-rzg2l.c
@@ -0,0 +1,462 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Renesas RZ/G2L IRQC Driver
+ *
+ * Copyright (C) 2022 Renesas Electronics Corporation.
+ *
+ * Author: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
+ */
+
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/irqchip.h>
+#include <linux/irqdomain.h>
+#include <linux/of_address.h>
+#include <linux/reset.h>
+#include <linux/spinlock.h>
+
+#define IRQC_IRQ_START 1
+#define IRQC_IRQ_COUNT 8
+#define IRQC_TINT_START 9
+#define IRQC_TINT_COUNT 32
+#define IRQC_NUM_IRQ 41
+
+#define ISCR 0x10
+#define IITSR 0x14
+#define TSCR 0x20
+#define TITSR0 0x24
+#define TITSR1 0x28
+#define TITSR0_MAX_INT 16
+#define TITSEL_WIDTH 0x2
+#define TSSR(n) (0x30 + ((n) * 4))
+#define TIEN BIT(7)
+#define TSSEL_SHIFT(n) (8 * (n))
+#define TSSEL_MASK GENMASK(7, 0)
+#define IRQ_MASK 0x3
+
+#define TSSR_OFFSET(n) ((n) % 4)
+#define TSSR_INDEX(n) ((n) / 4)
+
+#define TITSR_TITSEL_EDGE_RISING 0
+#define TITSR_TITSEL_EDGE_FALLING 1
+#define TITSR_TITSEL_LEVEL_HIGH 2
+#define TITSR_TITSEL_LEVEL_LOW 3
+
+#define IITSR_IITSEL(n, sense) ((sense) << ((n) * 2))
+#define IITSR_IITSEL_LEVEL_LOW 0
+#define IITSR_IITSEL_EDGE_FALLING 1
+#define IITSR_IITSEL_EDGE_RISING 2
+#define IITSR_IITSEL_EDGE_BOTH 3
+#define IITSR_IITSEL_MASK(n) IITSR_IITSEL((n), 3)
+
+#define TINT_EXTRACT_HWIRQ(x) ((x) & ~GENMASK(31, 16))
+#define TINT_EXTRACT_GPIOINT(x) ((x) >> 16)
+
+struct rzg2l_irqc_priv {
+ void __iomem *base;
+ struct of_phandle_args map[IRQC_NUM_IRQ];
+ raw_spinlock_t lock;
+};
+
+struct rzg2l_irqc_chip_data {
+ int tint;
+};
+
+static struct rzg2l_irqc_priv *irq_data_to_priv(struct irq_data *data)
+{
+ return data->domain->host_data;
+}
+
+static void rzg2l_irq_eoi(struct irq_data *d)
+{
+ struct rzg2l_irqc_priv *priv = irq_data_to_priv(d);
+ unsigned int hw_irq = irqd_to_hwirq(d) - IRQC_IRQ_START;
+ u16 bit = BIT(hw_irq);
+ unsigned long flags;
+ u32 reg;
+
+ raw_spin_lock_irqsave(&priv->lock, flags);
+ reg = readl_relaxed(priv->base + ISCR);
+ if (reg & bit)
+ writel_relaxed(GENMASK(IRQC_IRQ_COUNT - 1, 0) & ~bit,
+ priv->base + ISCR);
+ raw_spin_unlock_irqrestore(&priv->lock, flags);
+ irq_chip_eoi_parent(d);
+}
+
+static void rzg2l_tint_eoi(struct irq_data *d)
+{
+ struct rzg2l_irqc_priv *priv = irq_data_to_priv(d);
+ unsigned int hw_irq = irqd_to_hwirq(d);
+ u32 bit = BIT(hw_irq - IRQC_TINT_START);
+ unsigned long flags;
+ u32 reg;
+
+ raw_spin_lock_irqsave(&priv->lock, flags);
+ reg = readl_relaxed(priv->base + TSCR);
+ if (reg & bit)
+ writel_relaxed(GENMASK(IRQC_TINT_COUNT - 1, 0) & ~bit,
+ priv->base + TSCR);
+ raw_spin_unlock_irqrestore(&priv->lock, flags);
+ irq_chip_eoi_parent(d);
+}
+
+static void rzg2l_irqc_eoi(struct irq_data *d)
+{
+ unsigned int hw_irq = irqd_to_hwirq(d);
+
+ if (hw_irq >= IRQC_IRQ_START && hw_irq <= IRQC_IRQ_COUNT)
+ return rzg2l_irq_eoi(d);
+ else if (hw_irq >= IRQC_TINT_START && hw_irq <= IRQC_TINT_COUNT)
+ return rzg2l_tint_eoi(d);
+}
+
+static void rzg2l_irqc_irq_disable(struct irq_data *d)
+{
+ unsigned int hw_irq = irqd_to_hwirq(d);
+
+ if (hw_irq >= IRQC_TINT_START && hw_irq <= IRQC_TINT_COUNT) {
+ struct rzg2l_irqc_priv *priv = irq_data_to_priv(d);
+ u32 offset = hw_irq - IRQC_TINT_START;
+ u32 tssr_offset = TSSR_OFFSET(offset);
+ u8 tssr_index = TSSR_INDEX(offset);
+ unsigned long flags;
+ u32 reg;
+
+ raw_spin_lock_irqsave(&priv->lock, flags);
+ reg = readl_relaxed(priv->base + TSSR(tssr_index));
+ reg &= ~(TSSEL_MASK << tssr_offset);
+ writel_relaxed(reg, priv->base + TSSR(tssr_index));
+ raw_spin_unlock_irqrestore(&priv->lock, flags);
+ }
+ irq_chip_disable_parent(d);
+}
+
+static void rzg2l_irqc_irq_enable(struct irq_data *d)
+{
+ unsigned int hw_irq = irqd_to_hwirq(d);
+
+ if (hw_irq >= IRQC_TINT_START && hw_irq <= IRQC_TINT_COUNT) {
+ struct rzg2l_irqc_priv *priv = irq_data_to_priv(d);
+ struct rzg2l_irqc_chip_data *chip_data = d->chip_data;
+ u32 offset = hw_irq - IRQC_TINT_START;
+ u32 tssr_offset = TSSR_OFFSET(offset);
+ u8 tssr_index = TSSR_INDEX(offset);
+ unsigned long flags;
+ u32 reg;
+
+ raw_spin_lock_irqsave(&priv->lock, flags);
+ reg = readl_relaxed(priv->base + TSSR(tssr_index));
+ reg |= (TIEN | chip_data->tint) << TSSEL_SHIFT(tssr_offset);
+ writel_relaxed(reg, priv->base + TSSR(tssr_index));
+ raw_spin_unlock_irqrestore(&priv->lock, flags);
+ }
+ irq_chip_enable_parent(d);
+}
+
+static int rzg2l_irq_set_type(struct irq_data *d, unsigned int type)
+{
+ unsigned int hw_irq = irqd_to_hwirq(d) - IRQC_IRQ_START;
+ struct rzg2l_irqc_priv *priv = irq_data_to_priv(d);
+ unsigned long flags;
+ u16 sense, tmp;
+
+ switch (type & IRQ_TYPE_SENSE_MASK) {
+ case IRQ_TYPE_LEVEL_LOW:
+ sense = IITSR_IITSEL_LEVEL_LOW;
+ break;
+
+ case IRQ_TYPE_EDGE_FALLING:
+ sense = IITSR_IITSEL_EDGE_FALLING;
+ break;
+
+ case IRQ_TYPE_EDGE_RISING:
+ sense = IITSR_IITSEL_EDGE_RISING;
+ break;
+
+ case IRQ_TYPE_EDGE_BOTH:
+ sense = IITSR_IITSEL_EDGE_BOTH;
+ break;
+
+ default:
+ return -EINVAL;
+ }
+
+ raw_spin_lock_irqsave(&priv->lock, flags);
+ tmp = readl_relaxed(priv->base + IITSR);
+ tmp &= ~IITSR_IITSEL_MASK(hw_irq);
+ tmp |= IITSR_IITSEL(hw_irq, sense);
+ writel_relaxed(tmp, priv->base + IITSR);
+ raw_spin_unlock_irqrestore(&priv->lock, flags);
+
+ return 0;
+}
+
+static int rzg2l_tint_set_edge(struct irq_data *d, unsigned int type)
+{
+ struct rzg2l_irqc_priv *priv = irq_data_to_priv(d);
+ unsigned int hwirq = irqd_to_hwirq(d);
+ u32 titseln = hwirq - IRQC_TINT_START;
+ unsigned long flags;
+ u32 offset;
+ u8 sense;
+ u32 reg;
+
+ switch (type & IRQ_TYPE_SENSE_MASK) {
+ case IRQ_TYPE_EDGE_RISING:
+ sense = TITSR_TITSEL_EDGE_RISING;
+ break;
+
+ case IRQ_TYPE_EDGE_FALLING:
+ sense = TITSR_TITSEL_EDGE_FALLING;
+ break;
+
+ default:
+ return -EINVAL;
+ }
+
+ if (titseln < TITSR0_MAX_INT) {
+ offset = TITSR0;
+ } else {
+ titseln /= TITSEL_WIDTH;
+ offset = TITSR1;
+ }
+
+ raw_spin_lock_irqsave(&priv->lock, flags);
+ reg = readl_relaxed(priv->base + offset);
+ reg &= ~(IRQ_MASK << (titseln * TITSEL_WIDTH));
+ reg |= sense << (titseln * TITSEL_WIDTH);
+ writel_relaxed(reg, priv->base + offset);
+ raw_spin_unlock_irqrestore(&priv->lock, flags);
+
+ return 0;
+}
+
+static int rzg2l_irqc_set_type(struct irq_data *d, unsigned int type)
+{
+ unsigned int hw_irq = irqd_to_hwirq(d);
+
+ if (hw_irq >= IRQC_IRQ_START && hw_irq <= IRQC_IRQ_COUNT)
+ return rzg2l_irq_set_type(d, type);
+ else if (hw_irq >= IRQC_TINT_START && hw_irq <= IRQC_TINT_COUNT)
+ return rzg2l_tint_set_edge(d, type);
+
+ return -EINVAL;
+}
+
+static struct irq_chip irqc_chip = {
+ .name = "rzg2l-irqc",
+ .irq_eoi = rzg2l_irqc_eoi,
+ .irq_mask = irq_chip_mask_parent,
+ .irq_unmask = irq_chip_unmask_parent,
+ .irq_disable = rzg2l_irqc_irq_disable,
+ .irq_enable = rzg2l_irqc_irq_enable,
+ .irq_get_irqchip_state = irq_chip_get_parent_state,
+ .irq_set_irqchip_state = irq_chip_set_parent_state,
+ .irq_retrigger = irq_chip_retrigger_hierarchy,
+ .irq_set_type = rzg2l_irqc_set_type,
+ .flags = IRQCHIP_MASK_ON_SUSPEND |
+ IRQCHIP_SET_TYPE_MASKED |
+ IRQCHIP_SKIP_SET_WAKE,
+};
+
+static int rzg2l_irqc_alloc(struct irq_domain *domain, unsigned int virq,
+ unsigned int nr_irqs, void *arg)
+{
+ struct rzg2l_irqc_priv *priv = domain->host_data;
+ struct rzg2l_irqc_chip_data *chip_data = NULL;
+ struct irq_fwspec spec;
+ irq_hw_number_t hwirq;
+ int tint = -EINVAL;
+ unsigned int type;
+ unsigned int i;
+ int ret;
+
+ ret = irq_domain_translate_twocell(domain, arg, &hwirq, &type);
+ if (ret)
+ return ret;
+
+ /*
+ * For TINIT interrupts ie where pinctrl driver is child of irqc domain
+ * the hwirq and TINT are encoded in fwspec->param[0].
+ * hwirq for TINIT range from 9-40, hwirq is embedded 0-15 bits and TINT
+ * from 16-31 bits. TINIT from the pinctrl driver needs to be programmed
+ * in IRQC registers to enable a given gpio pin as interrupt.
+ */
+ if (hwirq > IRQC_IRQ_COUNT) {
+ tint = TINT_EXTRACT_GPIOINT(hwirq);
+ hwirq = TINT_EXTRACT_HWIRQ(hwirq);
+ }
+
+ if (hwirq > (IRQC_NUM_IRQ - 1))
+ return -EINVAL;
+
+ if (tint != -EINVAL && (hwirq < IRQC_TINT_START || hwirq > (IRQC_NUM_IRQ - 1)))
+ return -EINVAL;
+
+ chip_data = kzalloc(sizeof(*chip_data), GFP_KERNEL);
+ if (!chip_data)
+ return -ENOMEM;
+ chip_data->tint = tint;
+
+ ret = irq_domain_set_hwirq_and_chip(domain, virq, hwirq, &irqc_chip,
+ chip_data);
+ if (ret) {
+ kfree(chip_data);
+ return ret;
+ }
+
+ spec.fwnode = domain->parent->fwnode;
+ spec.param_count = priv->map[hwirq].args_count;
+ for (i = 0; i < spec.param_count; i++)
+ spec.param[i] = priv->map[hwirq].args[i];
+
+ ret = irq_domain_alloc_irqs_parent(domain, virq, nr_irqs, &spec);
+ if (ret)
+ kfree(chip_data);
+
+ return ret;
+}
+
+static void rzg2l_irqc_domain_free(struct irq_domain *domain, unsigned int virq,
+ unsigned int nr_irqs)
+{
+ struct irq_data *d;
+
+ d = irq_domain_get_irq_data(domain, virq);
+ if (d) {
+ struct rzg2l_irqc_chip_data *chip_data = d->chip_data;
+
+ kfree(chip_data);
+ }
+ irq_domain_free_irqs_common(domain, virq, nr_irqs);
+}
+
+static const struct irq_domain_ops rzg2l_irqc_domain_ops = {
+ .alloc = rzg2l_irqc_alloc,
+ .free = rzg2l_irqc_domain_free,
+ .translate = irq_domain_translate_twocell,
+};
+
+static int rzg2l_irqc_parse_map(struct rzg2l_irqc_priv *priv,
+ struct device_node *np,
+ struct device_node *parent)
+{
+ unsigned int len, j;
+ const __be32 *range;
+
+ range = of_get_property(np, "interrupts", &len);
+ if (!range)
+ return -EINVAL;
+
+ for (len /= sizeof(*range), j = 0; len >= 3; len -= 3) {
+ if (j >= IRQC_NUM_IRQ)
+ return -EINVAL;
+
+ priv->map[j].args[0] = be32_to_cpu(*range++);
+ priv->map[j].args[1] = be32_to_cpu(*range++);
+ priv->map[j].args[2] = be32_to_cpu(*range++);
+ priv->map[j].args_count = 3;
+ j++;
+ }
+
+ return 0;
+}
+
+static int rzg2l_irqc_init(struct device_node *node, struct device_node *parent)
+{
+ struct irq_domain *irq_domain, *parent_domain;
+ struct reset_control *resetn;
+ struct rzg2l_irqc_priv *priv;
+ struct clk *clk;
+ struct clk *pclk;
+ int ret;
+
+ priv = kzalloc(sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ priv->base = of_iomap(node, 0);
+ if (!priv->base) {
+ ret = -ENXIO;
+ goto free_priv;
+ }
+
+ clk = of_clk_get_by_name(node, "clk");
+ if (IS_ERR(clk)) {
+ ret = IS_ERR(clk);
+ goto iounmap_base;
+ }
+
+ pclk = of_clk_get_by_name(node, "pclk");
+ if (IS_ERR(pclk)) {
+ ret = IS_ERR(pclk);
+ goto iounmap_base;
+ }
+
+ resetn = of_reset_control_get_exclusive_by_index(node, 0);
+ if (IS_ERR(resetn)) {
+ ret = IS_ERR(resetn);
+ goto iounmap_base;
+ }
+
+ parent_domain = irq_find_host(parent);
+ if (!parent_domain) {
+ pr_err("%pOF: cannot find parent domain\n", node);
+ ret = -ENODEV;
+ goto iounmap_base;
+ }
+
+ ret = rzg2l_irqc_parse_map(priv, node, parent);
+ if (ret) {
+ pr_err("%pOF: cannot parse interrupts: %d\n", node, ret);
+ goto iounmap_base;
+ }
+
+ ret = reset_control_deassert(resetn);
+ if (ret) {
+ pr_err("%pOF: failed to deassert resetn pin, %d\n", node, ret);
+ goto iounmap_base;
+ }
+
+ raw_spin_lock_init(&priv->lock);
+
+ ret = clk_prepare_enable(clk);
+ if (ret)
+ goto assert_reset;
+
+ ret = clk_prepare_enable(pclk);
+ if (ret)
+ goto disable_clk;
+
+ irq_domain = irq_domain_add_hierarchy(parent_domain, 0, IRQC_NUM_IRQ,
+ node, &rzg2l_irqc_domain_ops,
+ priv);
+ if (!irq_domain) {
+ pr_err("%pOF: cannot initialize irq domain\n", node);
+ ret = -ENOMEM;
+ goto fail_irq_domain;
+ }
+
+ return 0;
+
+fail_irq_domain:
+ clk_disable_unprepare(pclk);
+disable_clk:
+ clk_disable_unprepare(clk);
+assert_reset:
+ reset_control_assert(resetn);
+iounmap_base:
+ iounmap(priv->base);
+free_priv:
+ kfree(priv);
+ return ret;
+}
+
+IRQCHIP_PLATFORM_DRIVER_BEGIN(rzg2l_irqc)
+IRQCHIP_MATCH("renesas,rzg2l-irqc", rzg2l_irqc_init)
+IRQCHIP_PLATFORM_DRIVER_END(rzg2l_irqc)
+MODULE_AUTHOR("Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>");
+MODULE_DESCRIPTION("Renesas RZ/G2L IRQC Driver");
+MODULE_LICENSE("GPL v2");
--
2.17.1