Re: [PATCH v3 2/2] irqchip/mchp-eic: add support
From: Marc Zyngier <maz@kernel.org>
Date: 2021-09-20 12:53:15
Also in:
linux-arm-kernel, lkml
On Fri, 10 Sep 2021 07:06:56 +0100, Claudiu Beznea [off-list ref] wrote:
quoted hunk ↗ jump to hunk
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 <redacted> --- MAINTAINERS | 6 + drivers/irqchip/Kconfig | 8 + drivers/irqchip/Makefile | 1 + drivers/irqchip/irq-mchp-eic.c | 314 +++++++++++++++++++++++++++++++++ 4 files changed, 329 insertions(+) create mode 100644 drivers/irqchip/irq-mchp-eic.cdiff --git a/MAINTAINERS b/MAINTAINERS index a61f4f3b78a9..87174babb0ef 100644 --- a/MAINTAINERS +++ b/MAINTAINERS@@ -12141,6 +12141,12 @@ L: linux-crypto@vger.kernel.org S: Maintained F: drivers/crypto/atmel-ecc.* +MICROCHIP EIC DRIVER +M: Claudiu Beznea <claudiu.beznea@microchip.com> +L: linux-arm-kernel@lists.infradead.org (moderated for non-subscribers) +S: Supported +F: drivers/irqchip/irq-mchp-eic.c + MICROCHIP I2C DRIVER M: Codrin Ciubotariu <codrin.ciubotariu@microchip.com> L: linux-i2c@vger.kernel.orgdiff --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. + endmenudiff --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.odiff --git a/drivers/irqchip/irq-mchp-eic.c b/drivers/irqchip/irq-mchp-eic.c new file mode 100644 index 000000000000..ab24a464b929 --- /dev/null +++ b/drivers/irqchip/irq-mchp-eic.c@@ -0,0 +1,314 @@ +// 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@microchip.com> + */ +#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 <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 + * @dev: eic device + * @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 device *dev; + struct clk *clk; + struct irq_domain *domain; + u32 irqs[MCHP_EIC_NIRQ]; + u32 scfg[MCHP_EIC_NIRQ]; + u32 wakeup_source; +}; + +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_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) +{ + struct mchp_eic *eic = irq_data_get_irq_chip_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) +{ + struct mchp_eic *eic = irq_data_get_irq_chip_data(d); + 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) +{ + 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", + .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_translate(struct irq_domain *d, + struct irq_fwspec *fwspec, + unsigned long *hwirq, + unsigned int *type) +{ + if (!is_of_node(fwspec->fwnode)) + return -EINVAL; + + if (fwspec->param_count != 2 || fwspec->param[0] >= MCHP_EIC_NIRQ) + return -EINVAL; + + *hwirq = fwspec->param[0]; + *type = fwspec->param[1]; + + return 0; +}
Which is pretty much irq_domain_translate_twocell(). Please use that.
+
+static int mchp_eic_domain_alloc(struct irq_domain *domain, unsigned int virq,
+ unsigned int nr_irqs, void *data)
+{
+ struct mchp_eic *eic = domain->host_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 = mchp_eic_domain_translate(domain, fwspec, &hwirq, &type);
+ if (ret)
+ 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 = mchp_eic_domain_translate,
+ .alloc = mchp_eic_domain_alloc,
+ .free = irq_domain_free_irqs_common,
+};
+
+static int mchp_eic_probe(struct platform_device *pdev)
+{
+ struct irq_domain *parent_domain = NULL;
+ struct device *dev = &pdev->dev;
+ struct device_node *np = dev->of_node;
+ struct device_node *gic_node;
+ struct mchp_eic *eic;
+ int ret, i;
+
+ eic = devm_kzalloc(dev, sizeof(*eic), GFP_KERNEL);
+ if (!eic)
+ return -ENOMEM;
+
+ eic->base = devm_platform_get_and_ioremap_resource(pdev, 0, NULL);
+ if (IS_ERR(eic->base))
+ return PTR_ERR(eic->base);
+
+ gic_node = of_irq_find_parent(np);
+ if (gic_node)
+ parent_domain = irq_find_host(gic_node);
+ of_node_put(gic_node);
+ if (!parent_domain)
+ return -ENODEV;
+
+ eic->clk = devm_clk_get(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++) {
+ struct of_phandle_args irq;
+
+ /* Disable it, if any. */
+ writel_relaxed(0UL, eic->base + MCHP_EIC_SCFG(i));
+
+ ret = of_irq_parse_one(np, 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,
+ np, &mchp_eic_domain_ops, eic);
+ if (!eic->domain) {
+ ret = dev_err_probe(dev, -ENOMEM, "Failed to add domain\n");
+ goto clk_unprepare;
+ }
+
+ eic->dev = dev;
+ platform_set_drvdata(pdev, eic);
+
+ dev_info(dev, "EIC registered, nr_irqs %u\n", MCHP_EIC_NIRQ);
+
+ return 0;
+
+clk_unprepare:
+ clk_disable_unprepare(eic->clk);
+ return ret;
+}
+
+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_relaxed(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_relaxed(eic->scfg[hwirq], eic->base +
+ MCHP_EIC_SCFG(hwirq));
+
+ 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,
+ .driver = {
+ .name = "mchp-eic",
+ .of_match_table = of_match_ptr(mchp_eic_dt_ids),
+ .pm = pm_ptr(&mchp_eic_pm_ops),
+ },
+};
+builtin_platform_driver(mchp_eic_device_driver);Please use the IRQCHIP_PLATFORM_DRIVER_BEGIN() IRQCHIP_MATCH() IRQCHIP_PLATFORM_DRIVER_END() construct instead. See drivers/irqchip/qcom-pdc.c for an example. It will at the very least avoid exposing the unbind attribute that will lead to an explosion if touched. Thanks, M. -- Without deviation from the norm, progress is not possible.