diff options
Diffstat (limited to 'drivers/irqchip/irq-mchp-eic.c')
| -rw-r--r-- | drivers/irqchip/irq-mchp-eic.c | 280 |
1 files changed, 280 insertions, 0 deletions
diff --git a/drivers/irqchip/irq-mchp-eic.c b/drivers/irqchip/irq-mchp-eic.c new file mode 100644 index 000000000..c726a1983 --- /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@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 <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 (!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@microchip.com>"); |