Add support for Microchip External Interrupt Controller.

Signed-off-by: Claudiu Beznea <claudiu.bez...@microchip.com>
---
 MAINTAINERS                    |   6 +
 drivers/irqchip/Kconfig        |   7 +
 drivers/irqchip/Makefile       |   1 +
 drivers/irqchip/irq-mchp-eic.c | 350 +++++++++++++++++++++++++++++++++
 4 files changed, 364 insertions(+)
 create mode 100644 drivers/irqchip/irq-mchp-eic.c

diff --git a/MAINTAINERS b/MAINTAINERS
index a008b70f3c16..ea99e5a7f519 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -11585,6 +11585,12 @@ L:     linux-arm-ker...@lists.infradead.org (moderated 
for non-subscribers)
 S:     Supported
 F:     drivers/usb/gadget/udc/atmel_usba_udc.*
 
+MICROCHIP EIC DRIVER
+M:     Claudiu Beznea <claudiu.bez...@microchip.com>
+L:     linux-arm-ker...@lists.infradead.org (moderated for non-subscribers)
+S:     Supported
+F:     drivers/irqchip/irq-mchp-eic.c
+
 MICROCHIP WILC1000 WIFI DRIVER
 M:     Ajay Singh <ajay.kat...@microchip.com>
 M:     Claudiu Beznea <claudiu.bez...@microchip.com>
diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig
index 2aa79c32ee22..7c7ca33c3f7d 100644
--- a/drivers/irqchip/Kconfig
+++ b/drivers/irqchip/Kconfig
@@ -596,4 +596,11 @@ config MST_IRQ
        help
          Support MStar Interrupt Controller.
 
+config MCHP_EIC
+       bool "Microchip External Interrupt Controller"
+       depends on ARCH_AT91 || COMPILE_TEST
+       select IRQ_DOMAIN
+       help
+         Support for Microchip External Interrupt Controller.
+
 endmenu
diff --git a/drivers/irqchip/Makefile b/drivers/irqchip/Makefile
index 94c2885882ee..f3df6eb7c4c3 100644
--- a/drivers/irqchip/Makefile
+++ b/drivers/irqchip/Makefile
@@ -114,3 +114,4 @@ obj-$(CONFIG_LOONGSON_PCH_PIC)              += 
irq-loongson-pch-pic.o
 obj-$(CONFIG_LOONGSON_PCH_MSI)         += irq-loongson-pch-msi.o
 obj-$(CONFIG_MST_IRQ)                  += irq-mst-intc.o
 obj-$(CONFIG_SL28CPLD_INTC)            += irq-sl28cpld.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..ec01877fc75f
--- /dev/null
+++ b/drivers/irqchip/irq-mchp-eic.c
@@ -0,0 +1,350 @@
+// 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.bez...@microchip.com>
+ */
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/irqchip.h>
+#include <linux/irqdomain.h>
+#include <linux/module.h>
+#include <linux/of_address.h>
+#include <linux/platform_device.h>
+#include <linux/irqchip/chained_irq.h>
+
+#define MCHP_EIC_GFCS                  (0x0)
+#define MCHP_EIC_SCFG(x)               (0x4 + (x) * 0x4)
+#define MCHP_EIC_SCFG_FRZ              BIT(31)
+#define MCHP_EIC_SCFG_EN               BIT(16)
+#define MCHP_EIC_SCFG_LVL              BIT(9)
+#define MCHP_EIC_SCFG_POL              BIT(8)
+#define MCHP_EIC_SCFG_GFEN             BIT(4)
+#define MCHP_EIC_SCFG_GFSEL            GENMASK(1, 0)
+
+#define MCHP_EIC_NIRQ                  (2)
+#define MCHP_EIC_DEFAULT_WAIT_US       (100)
+
+/**
+ * struct mchp_eic - EIC private data structure
+ * @base: base address
+ * @dev: eic device
+ * @clk: peripheral clock
+ * @chip: irq chip
+ * @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 device *dev;
+       struct clk *clk;
+       struct irq_chip *chip;
+       struct irq_domain *domain;
+       u32 irqs[MCHP_EIC_NIRQ];
+       u32 scfg[MCHP_EIC_NIRQ];
+       u32 wakeup_source;
+};
+
+static void mchp_eic_wait_rdy(struct mchp_eic *eic, unsigned int hwirq,
+                             int delay_us)
+{
+       unsigned int tmp = readl(eic->base + MCHP_EIC_SCFG(hwirq));
+
+       while (delay_us >= 0 && tmp & BIT(hwirq)) {
+               udelay(1);
+               delay_us -= 1;
+               tmp = readl(eic->base + MCHP_EIC_SCFG(hwirq));
+       }
+
+       if (delay_us < 0)
+               dev_err(eic->dev, "Failed to configure IRQ=%u!\n", hwirq);
+}
+
+static void mchp_eic_irq_mask(struct irq_data *d)
+{
+       struct mchp_eic *eic = irq_data_get_irq_chip_data(d);
+       unsigned int tmp;
+
+       tmp = readl(eic->base + MCHP_EIC_SCFG(d->hwirq));
+       tmp &= ~MCHP_EIC_SCFG_EN;
+       writel(tmp, eic->base + MCHP_EIC_SCFG(d->hwirq));
+}
+
+static void mchp_eic_irq_unmask(struct irq_data *d)
+{
+       struct mchp_eic *eic = irq_data_get_irq_chip_data(d);
+       unsigned int tmp;
+
+       tmp = readl(eic->base + MCHP_EIC_SCFG(d->hwirq));
+       tmp |= MCHP_EIC_SCFG_EN;
+       writel(tmp, eic->base + MCHP_EIC_SCFG(d->hwirq));
+       mchp_eic_wait_rdy(eic, d->hwirq, MCHP_EIC_DEFAULT_WAIT_US);
+}
+
+static int mchp_eic_irq_set_type(struct irq_data *d, unsigned int type)
+{
+       struct mchp_eic *eic = irq_data_get_irq_chip_data(d);
+       unsigned int tmp;
+
+       tmp = readl(eic->base + MCHP_EIC_SCFG(d->hwirq));
+       tmp &= ~(MCHP_EIC_SCFG_POL | MCHP_EIC_SCFG_LVL);
+       switch (type) {
+       case IRQ_TYPE_LEVEL_HIGH:
+               irq_set_handler_locked(d, handle_level_irq);
+               tmp |= MCHP_EIC_SCFG_POL | MCHP_EIC_SCFG_LVL;
+               break;
+       case IRQ_TYPE_LEVEL_LOW:
+               irq_set_handler_locked(d, handle_level_irq);
+               tmp |= MCHP_EIC_SCFG_LVL;
+               break;
+       case IRQ_TYPE_EDGE_RISING:
+               irq_set_handler_locked(d, handle_edge_irq);
+               tmp |= MCHP_EIC_SCFG_POL;
+               break;
+       case IRQ_TYPE_EDGE_FALLING:
+               irq_set_handler_locked(d, handle_edge_irq);
+               break;
+       default:
+               return -EINVAL;
+       }
+
+       writel(tmp, eic->base + MCHP_EIC_SCFG(d->hwirq));
+
+       return 0;
+}
+
+static void mchp_eic_irq_ack(struct irq_data *d)
+{
+       /* Nothing to do here. */
+}
+
+static int mchp_eic_irq_set_wake(struct irq_data *d, unsigned int on)
+{
+       struct mchp_eic *eic = irq_data_get_irq_chip_data(d);
+
+       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 struct irq_chip mchp_eic_chip = {
+       .name           = "eic-irq",
+       .flags          = IRQCHIP_MASK_ON_SUSPEND,
+       .irq_mask       = mchp_eic_irq_mask,
+       .irq_unmask     = mchp_eic_irq_unmask,
+       .irq_set_type   = mchp_eic_irq_set_type,
+       .irq_ack        = mchp_eic_irq_ack,
+       .irq_set_wake   = mchp_eic_irq_set_wake,
+};
+
+static int mchp_eic_domain_map(struct irq_domain *d, unsigned int virq,
+                              irq_hw_number_t hw)
+{
+       struct mchp_eic *eic = d->host_data;
+
+       irq_set_chip_data(virq, eic);
+       irq_set_chip_and_handler(virq, eic->chip, handle_bad_irq);
+       irq_set_probe(virq);
+
+       return 0;
+}
+
+static int mchp_eic_domain_xlate(struct irq_domain *d, struct device_node 
*node,
+                                const u32 *intspec, unsigned int intsize,
+                                irq_hw_number_t *out_hwirq,
+                                unsigned int *out_type)
+{
+       struct mchp_eic *eic = d->host_data;
+       unsigned int tmp, i;
+
+       if (WARN_ON(intsize < 2))
+               return -EINVAL;
+
+       if (WARN_ON(intspec[0] > MCHP_EIC_NIRQ))
+               return -EINVAL;
+
+       *out_hwirq = intspec[0];
+       *out_type = intspec[1] & IRQ_TYPE_SENSE_MASK;
+
+       if (intsize == 3) {
+               /* Validate against available filters. */
+               for (i = 0; i <= MCHP_EIC_SCFG_GFSEL; i++) {
+                       if (intspec[2] == (2 << i))
+                               break;
+               }
+               if (i == MCHP_EIC_SCFG_GFSEL + 1)
+                       return -EINVAL;
+
+               /* Enable glitch filter. */
+               tmp = readl(eic->base + MCHP_EIC_SCFG(*out_hwirq));
+               tmp |= MCHP_EIC_SCFG_GFEN;
+               tmp &= ~MCHP_EIC_SCFG_GFSEL;
+               tmp |= i;
+               writel(tmp, eic->base + MCHP_EIC_SCFG(*out_hwirq));
+
+               /* Wait for glitch filter to be enabled. */
+               mchp_eic_wait_rdy(eic, *out_hwirq, MCHP_EIC_DEFAULT_WAIT_US);
+       }
+
+       return 0;
+}
+
+static const struct irq_domain_ops mchp_eic_domain_ops = {
+       .map            = mchp_eic_domain_map,
+       .xlate          = mchp_eic_domain_xlate,
+};
+
+static void mchp_eic_irq_handler(struct irq_desc *desc)
+{
+       struct mchp_eic *eic = irq_desc_get_handler_data(desc);
+       struct irq_chip *chip = irq_desc_get_chip(desc);
+       unsigned int hwirq, irq = irq_desc_get_irq(desc);
+
+       for (hwirq = 0; hwirq < MCHP_EIC_NIRQ; hwirq++) {
+               if (eic->irqs[hwirq] == irq)
+                       break;
+       }
+       if (hwirq == MCHP_EIC_NIRQ)
+               return;
+
+       chained_irq_enter(chip, desc);
+       generic_handle_irq(irq_find_mapping(eic->domain, hwirq));
+       chained_irq_exit(chip, desc);
+}
+
+static int mchp_eic_probe(struct platform_device *pdev)
+{
+       struct resource *res;
+       struct mchp_eic *eic;
+       int ret, i;
+
+       eic = devm_kzalloc(&pdev->dev, sizeof(*eic), GFP_KERNEL);
+       if (!eic)
+               return -ENOMEM;
+
+       res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+       eic->base = devm_ioremap_resource(&pdev->dev, res);
+       if (IS_ERR(eic->base))
+               return PTR_ERR(eic->base);
+
+       eic->clk = devm_clk_get(&pdev->dev, NULL);
+       if (IS_ERR(eic->clk))
+               return PTR_ERR(eic->clk);
+
+       ret = clk_prepare_enable(eic->clk);
+       if (ret)
+               return ret;
+
+       for (i = 0; i < MCHP_EIC_NIRQ; i++) {
+               /* Disable it, if any. */
+               writel(0UL, eic->base + MCHP_EIC_SCFG(i));
+
+               res = platform_get_resource(pdev, IORESOURCE_IRQ, i);
+               if (!res) {
+                       ret = dev_err_probe(&pdev->dev, -EINVAL,
+                                           "Failed to get hwirq=%d\n", i);
+                       goto clk_unprepare;
+               }
+
+               eic->irqs[i] = res->start;
+               irq_set_chained_handler(res->start, mchp_eic_irq_handler);
+               irq_set_handler_data(res->start, eic);
+       }
+
+       eic->dev = &pdev->dev;
+       eic->chip = &mchp_eic_chip;
+
+       eic->domain = irq_domain_add_linear(pdev->dev.of_node, MCHP_EIC_NIRQ,
+                                           &mchp_eic_domain_ops, eic);
+       if (!eic->domain) {
+               ret = dev_err_probe(&pdev->dev, -ENODEV,
+                                   "Failed to regiter irq domain!\n");
+               goto clk_unprepare;
+       }
+       eic->domain->name = "eic";
+
+       platform_set_drvdata(pdev, eic);
+
+       dev_info(&pdev->dev, "EIC registered, nr_irqs %u\n", MCHP_EIC_NIRQ);
+
+       return 0;
+
+clk_unprepare:
+       clk_disable_unprepare(eic->clk);
+       return ret;
+}
+
+static int mchp_eic_remove(struct platform_device *pdev)
+{
+       struct mchp_eic *eic = platform_get_drvdata(pdev);
+
+       irq_domain_remove(eic->domain);
+       clk_disable_unprepare(eic->clk);
+
+       return 0;
+}
+
+static int __maybe_unused mchp_eic_suspend(struct device *dev)
+{
+       struct mchp_eic *eic = dev_get_drvdata(dev);
+       unsigned int hwirq;
+
+       for (hwirq = 0; hwirq < MCHP_EIC_NIRQ; hwirq++)
+               eic->scfg[hwirq] = readl(eic->base + MCHP_EIC_SCFG(hwirq));
+
+       if (!eic->wakeup_source)
+               clk_disable_unprepare(eic->clk);
+
+       return 0;
+}
+
+static int __maybe_unused mchp_eic_resume(struct device *dev)
+{
+       struct mchp_eic *eic = dev_get_drvdata(dev);
+       unsigned int hwirq;
+
+       if (!eic->wakeup_source)
+               clk_prepare_enable(eic->clk);
+
+       for (hwirq = 0; hwirq < MCHP_EIC_NIRQ; hwirq++) {
+               writel(eic->scfg[hwirq], eic->base + MCHP_EIC_SCFG(hwirq));
+               mchp_eic_wait_rdy(eic, hwirq, MCHP_EIC_DEFAULT_WAIT_US);
+       }
+
+       return 0;
+}
+
+static const struct dev_pm_ops mchp_eic_pm_ops = {
+       SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(mchp_eic_suspend, mchp_eic_resume)
+};
+
+static const struct of_device_id mchp_eic_dt_ids[] = {
+       { .compatible = "microchip,sama7g5-eic", },
+       { },
+};
+MODULE_DEVICE_TABLE(of, mchp_eic_dt_ids);
+
+static struct platform_driver mchp_eic_device_driver = {
+       .probe          = mchp_eic_probe,
+       .remove         = mchp_eic_remove,
+       .driver         = {
+               .name = "mchp-eic",
+               .of_match_table = of_match_ptr(mchp_eic_dt_ids),
+               .pm = pm_ptr(&mchp_eic_pm_ops),
+       },
+};
+module_platform_driver(mchp_eic_device_driver);
+
+MODULE_DESCRIPTION("Microchip External Interrupt Controller");
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Claudiu Beznea <claudiu.bez...@microchip.com>");
-- 
2.25.1

Reply via email to