Add support for Microchip External Interrupt Controller. The controller
supports 2 external interrupt lines. For every external input there is
a connection to GIC. The interrupt controllers contains only 4
registers:
- EIC_GFCS (read only): which indicates that glitch filter configuration
is ready (not addressed in this implementation)
- EIC_SCFG0R, EIC_SCFG1R (read, write): allows per interrupt specific
settings: enable, polarity/edge settings, glitch filter settings
- EIC_WPMR, EIC_WPSR: enables write protection mode specific settings
(which are architecture specific) for the controller and are not
addressed in this implementation
Signed-off-by: Claudiu Beznea <claudiu.beznea@xxxxxxxxxxxxx>
---
MAINTAINERS | 6 +
drivers/irqchip/Kconfig | 8 +
drivers/irqchip/Makefile | 1 +
drivers/irqchip/irq-mchp-eic.c | 280 +++++++++++++++++++++++++++++++++
4 files changed, 295 insertions(+)
create mode 100644 drivers/irqchip/irq-mchp-eic.c
diff --git a/MAINTAINERS b/MAINTAINERS
index eeb4c70b3d5b..18e41192b311 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -12253,6 +12253,12 @@ L: linux-crypto@xxxxxxxxxxxxxxx
S: Maintained
F: drivers/crypto/atmel-ecc.*
+MICROCHIP EIC DRIVER
+M: Claudiu Beznea <claudiu.beznea@xxxxxxxxxxxxx>
+L: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx (moderated for non-subscribers)
+S: Supported
+F: drivers/irqchip/irq-mchp-eic.c
+
MICROCHIP I2C DRIVER
M: Codrin Ciubotariu <codrin.ciubotariu@xxxxxxxxxxxxx>
L: linux-i2c@xxxxxxxxxxxxxxx
diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig
index 4d5924e9f766..450c7b8ab30f 100644
--- a/drivers/irqchip/Kconfig
+++ b/drivers/irqchip/Kconfig
@@ -601,4 +601,12 @@ config APPLE_AIC
Support for the Apple Interrupt Controller found on Apple Silicon SoCs,
such as the M1.
+config MCHP_EIC
+ bool "Microchip External Interrupt Controller"
+ depends on ARCH_AT91 || COMPILE_TEST
+ select IRQ_DOMAIN
+ select IRQ_DOMAIN_HIERARCHY
+ help
+ Support for Microchip External Interrupt Controller.
+
endmenu
diff --git a/drivers/irqchip/Makefile b/drivers/irqchip/Makefile
index f88cbf36a9d2..c1f611cbfbf8 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_MCHP_EIC) += irq-mchp-eic.o
diff --git a/drivers/irqchip/irq-mchp-eic.c b/drivers/irqchip/irq-mchp-eic.c
new file mode 100644
index 000000000000..09b7a8cdb611
--- /dev/null
+++ b/drivers/irqchip/irq-mchp-eic.c
@@ -0,0 +1,280 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Microchip External Interrupt Controller driver
+ *
+ * Copyright (C) 2021 Microchip Technology Inc. and its subsidiaries
+ *
+ * Author: Claudiu Beznea <claudiu.beznea@xxxxxxxxxxxxx>
+ */
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/irqchip.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/syscore_ops.h>
+
+#include <dt-bindings/interrupt-controller/arm-gic.h>
+
+#define MCHP_EIC_GFCS (0x0)
+#define MCHP_EIC_SCFG(x) (0x4 + (x) * 0x4)
+#define MCHP_EIC_SCFG_EN BIT(16)
+#define MCHP_EIC_SCFG_LVL BIT(9)
+#define MCHP_EIC_SCFG_POL BIT(8)
+
+#define MCHP_EIC_NIRQ (2)
+
+/*
+ * struct mchp_eic - EIC private data structure
+ * @base: base address
+ * @clk: peripheral clock
+ * @domain: irq domain
+ * @irqs: irqs b/w eic and gic
+ * @scfg: backup for scfg registers (necessary for backup and self-refresh mode)
+ * @wakeup_source: wakeup source mask
+ */
+struct mchp_eic {
+ void __iomem *base;
+ struct clk *clk;
+ struct irq_domain *domain;
+ u32 irqs[MCHP_EIC_NIRQ];
+ u32 scfg[MCHP_EIC_NIRQ];
+ u32 wakeup_source;
+};
+
+static struct mchp_eic *eic;
+
+static void mchp_eic_irq_mask(struct irq_data *d)
+{
+ unsigned int tmp;
+
+ tmp = readl_relaxed(eic->base + MCHP_EIC_SCFG(d->hwirq));
+ tmp &= ~MCHP_EIC_SCFG_EN;
+ writel_relaxed(tmp, eic->base + MCHP_EIC_SCFG(d->hwirq));
+
+ irq_chip_mask_parent(d);
+}
+
+static void mchp_eic_irq_unmask(struct irq_data *d)
+{
+ unsigned int tmp;
+
+ tmp = readl_relaxed(eic->base + MCHP_EIC_SCFG(d->hwirq));
+ tmp |= MCHP_EIC_SCFG_EN;
+ writel_relaxed(tmp, eic->base + MCHP_EIC_SCFG(d->hwirq));
+
+ irq_chip_unmask_parent(d);
+}
+
+static int mchp_eic_irq_set_type(struct irq_data *d, unsigned int type)
+{
+ unsigned int parent_irq_type;
+ unsigned int tmp;
+
+ tmp = readl_relaxed(eic->base + MCHP_EIC_SCFG(d->hwirq));
+ tmp &= ~(MCHP_EIC_SCFG_POL | MCHP_EIC_SCFG_LVL);
+ switch (type) {
+ case IRQ_TYPE_LEVEL_HIGH:
+ tmp |= MCHP_EIC_SCFG_POL | MCHP_EIC_SCFG_LVL;
+ parent_irq_type = IRQ_TYPE_LEVEL_HIGH;
+ break;
+ case IRQ_TYPE_LEVEL_LOW:
+ tmp |= MCHP_EIC_SCFG_LVL;
+ parent_irq_type = IRQ_TYPE_LEVEL_HIGH;
+ break;
+ case IRQ_TYPE_EDGE_RISING:
+ parent_irq_type = IRQ_TYPE_EDGE_RISING;
+ break;
+ case IRQ_TYPE_EDGE_FALLING:
+ tmp |= MCHP_EIC_SCFG_POL;
+ parent_irq_type = IRQ_TYPE_EDGE_RISING;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ writel_relaxed(tmp, eic->base + MCHP_EIC_SCFG(d->hwirq));
+
+ return irq_chip_set_type_parent(d, parent_irq_type);
+}
+
+static int mchp_eic_irq_set_wake(struct irq_data *d, unsigned int on)
+{
+ irq_set_irq_wake(eic->irqs[d->hwirq], on);
+ if (on)
+ eic->wakeup_source |= BIT(d->hwirq);
+ else
+ eic->wakeup_source &= ~BIT(d->hwirq);
+
+ return 0;
+}
+
+static int mchp_eic_irq_suspend(void)
+{
+ unsigned int hwirq;
+
+ for (hwirq = 0; hwirq < MCHP_EIC_NIRQ; hwirq++)
+ eic->scfg[hwirq] = readl_relaxed(eic->base +
+ MCHP_EIC_SCFG(hwirq));
+
+ if (!eic->wakeup_source)
+ clk_disable_unprepare(eic->clk);
+
+ return 0;
+}
+
+static void mchp_eic_irq_resume(void)
+{
+ unsigned int hwirq;
+
+ if (!eic->wakeup_source)
+ clk_prepare_enable(eic->clk);
+
+ for (hwirq = 0; hwirq < MCHP_EIC_NIRQ; hwirq++)
+ writel_relaxed(eic->scfg[hwirq], eic->base +
+ MCHP_EIC_SCFG(hwirq));
+}
+
+static struct syscore_ops mchp_eic_syscore_ops = {
+ .suspend = mchp_eic_irq_suspend,
+ .resume = mchp_eic_irq_resume,
+};
+
+static struct irq_chip mchp_eic_chip = {
+ .name = "eic",
+ .flags = IRQCHIP_MASK_ON_SUSPEND | IRQCHIP_SET_TYPE_MASKED,
+ .irq_mask = mchp_eic_irq_mask,
+ .irq_unmask = mchp_eic_irq_unmask,
+ .irq_set_type = mchp_eic_irq_set_type,
+ .irq_ack = irq_chip_ack_parent,
+ .irq_eoi = irq_chip_eoi_parent,
+ .irq_retrigger = irq_chip_retrigger_hierarchy,
+ .irq_set_wake = mchp_eic_irq_set_wake,
+};
+
+static int mchp_eic_domain_alloc(struct irq_domain *domain, unsigned int virq,
+ unsigned int nr_irqs, void *data)
+{
+ struct irq_fwspec *fwspec = data;
+ struct irq_fwspec parent_fwspec;
+ irq_hw_number_t hwirq;
+ unsigned int type;
+ int ret;
+
+ if (WARN_ON(nr_irqs != 1))
+ return -EINVAL;
+
+ ret = irq_domain_translate_twocell(domain, fwspec, &hwirq, &type);
+ if (ret || hwirq >= MCHP_EIC_NIRQ)
+ return ret;
+
+ switch (type) {
+ case IRQ_TYPE_EDGE_RISING:
+ case IRQ_TYPE_LEVEL_HIGH:
+ break;
+ case IRQ_TYPE_EDGE_FALLING:
+ type = IRQ_TYPE_EDGE_RISING;
+ break;
+ case IRQ_TYPE_LEVEL_LOW:
+ type = IRQ_TYPE_LEVEL_HIGH;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ irq_domain_set_hwirq_and_chip(domain, virq, hwirq, &mchp_eic_chip, eic);
+
+ parent_fwspec.fwnode = domain->parent->fwnode;
+ parent_fwspec.param_count = 3;
+ parent_fwspec.param[0] = GIC_SPI;
+ parent_fwspec.param[1] = eic->irqs[hwirq];
+ parent_fwspec.param[2] = type;
+
+ return irq_domain_alloc_irqs_parent(domain, virq, 1, &parent_fwspec);
+}
+
+static const struct irq_domain_ops mchp_eic_domain_ops = {
+ .translate = irq_domain_translate_twocell,
+ .alloc = mchp_eic_domain_alloc,
+ .free = irq_domain_free_irqs_common,
+};
+
+static int mchp_eic_init(struct device_node *node, struct device_node *parent)
+{
+ struct irq_domain *parent_domain = NULL;
+ int ret, i;
+
+ eic = kzalloc(sizeof(*eic), GFP_KERNEL);
+ if (!eic)
+ return -ENOMEM;
+
+ eic->base = of_iomap(node, 0);
+ if (IS_ERR(eic->base)) {
+ ret = -ENOMEM;
+ goto free;
+ }
+
+ parent_domain = irq_find_host(parent);
+ if (!parent_domain) {
+ ret = -ENODEV;
+ goto unmap;
+ }
+
+ eic->clk = of_clk_get_by_name(node, "pclk");
+ if (IS_ERR(eic->clk)) {
+ ret = PTR_ERR(eic->clk);
+ goto unmap;
+ }
+
+ ret = clk_prepare_enable(eic->clk);
+ if (ret)
+ goto unmap;
+
+ for (i = 0; i < MCHP_EIC_NIRQ; i++) {
+ struct of_phandle_args irq;
+
+ /* Disable it, if any. */
+ writel_relaxed(0UL, eic->base + MCHP_EIC_SCFG(i));
+
+ ret = of_irq_parse_one(node, i, &irq);
+ if (ret)
+ goto clk_unprepare;
+
+ if (WARN_ON(irq.args_count != 3)) {
+ ret = -EINVAL;
+ goto clk_unprepare;
+ }
+
+ eic->irqs[i] = irq.args[1];
+ }
+
+ eic->domain = irq_domain_add_hierarchy(parent_domain, 0, MCHP_EIC_NIRQ,
+ node, &mchp_eic_domain_ops, eic);
+ if (!eic->domain) {
+ pr_err("%pOF: Failed to add domain\n", node);
+ ret = -ENODEV;
+ goto clk_unprepare;
+ }
+
+ register_syscore_ops(&mchp_eic_syscore_ops);
+
+ pr_info("%pOF: EIC registered, nr_irqs %u\n", node, MCHP_EIC_NIRQ);
+
+ return 0;
+
+clk_unprepare:
+ clk_disable_unprepare(eic->clk);
+unmap:
+ iounmap(eic->base);
+free:
+ kfree(eic);
+ return ret;
+}
+
+IRQCHIP_PLATFORM_DRIVER_BEGIN(mchp_eic)
+IRQCHIP_MATCH("microchip,sama7g5-eic", mchp_eic_init)
+IRQCHIP_PLATFORM_DRIVER_END(mchp_eic)
+
+MODULE_DESCRIPTION("Microchip External Interrupt Controller");
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Claudiu Beznea <claudiu.beznea@xxxxxxxxxxxxx>");
--
2.25.1
