diff options
Diffstat (limited to 'drivers/irqchip')
| -rw-r--r-- | drivers/irqchip/Kconfig | 10 | ||||
| -rw-r--r-- | drivers/irqchip/Makefile | 1 | ||||
| -rw-r--r-- | drivers/irqchip/irq-loongson-htpic.c | 149 |
3 files changed, 160 insertions, 0 deletions
diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig index c609eaa319d2..cae6f480c987 100644 --- a/drivers/irqchip/Kconfig +++ b/drivers/irqchip/Kconfig @@ -522,4 +522,14 @@ config LOONGSON_LIOINTC help Support for the Loongson Local I/O Interrupt Controller. +config LOONGSON_HTPIC + bool "Loongson3 HyperTransport PIC Controller" + depends on MACH_LOONGSON64 + default y + select IRQ_DOMAIN + select GENERIC_IRQ_CHIP + select I8259 + help + Support for the Loongson-3 HyperTransport PIC Controller. + endmenu diff --git a/drivers/irqchip/Makefile b/drivers/irqchip/Makefile index 5e7678efdfe6..37bbe39bf909 100644 --- a/drivers/irqchip/Makefile +++ b/drivers/irqchip/Makefile @@ -106,3 +106,4 @@ obj-$(CONFIG_LS1X_IRQ) += irq-ls1x.o obj-$(CONFIG_TI_SCI_INTR_IRQCHIP) += irq-ti-sci-intr.o obj-$(CONFIG_TI_SCI_INTA_IRQCHIP) += irq-ti-sci-inta.o obj-$(CONFIG_LOONGSON_LIOINTC) += irq-loongson-liointc.o +obj-$(CONFIG_LOONGSON_HTPIC) += irq-loongson-htpic.o diff --git a/drivers/irqchip/irq-loongson-htpic.c b/drivers/irqchip/irq-loongson-htpic.c new file mode 100644 index 000000000000..dd018c22ea83 --- /dev/null +++ b/drivers/irqchip/irq-loongson-htpic.c @@ -0,0 +1,149 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2020, Jiaxun Yang <jiaxun.yang@flygoat.com> + * Loongson HTPIC IRQ support + */ + +#include <linux/init.h> +#include <linux/of_address.h> +#include <linux/of_irq.h> +#include <linux/irqchip.h> +#include <linux/irqchip/chained_irq.h> +#include <linux/irq.h> +#include <linux/io.h> +#include <linux/syscore_ops.h> + +#include <asm/i8259.h> + +#define HTPIC_MAX_PARENT_IRQ 4 +#define HTINT_NUM_VECTORS 8 +#define HTINT_EN_OFF 0x20 + +struct loongson_htpic { + void __iomem *base; + struct irq_domain *domain; +}; + +static struct loongson_htpic *htpic; + +static void htpic_irq_dispatch(struct irq_desc *desc) +{ + struct loongson_htpic *priv = irq_desc_get_handler_data(desc); + struct irq_chip *chip = irq_desc_get_chip(desc); + uint32_t pending; + + chained_irq_enter(chip, desc); + pending = readl(priv->base); + /* Ack all IRQs at once, otherwise IRQ flood might happen */ + writel(pending, priv->base); + + if (!pending) + spurious_interrupt(); + + while (pending) { + int bit = __ffs(pending); + + if (unlikely(bit > 15)) { + spurious_interrupt(); + break; + } + + generic_handle_irq(irq_linear_revmap(priv->domain, bit)); + pending &= ~BIT(bit); + } + chained_irq_exit(chip, desc); +} + +static void htpic_reg_init(void) +{ + int i; + + for (i = 0; i < HTINT_NUM_VECTORS; i++) { + uint32_t val; + + /* Disable all HT Vectors */ + writel(0x0, htpic->base + HTINT_EN_OFF + i * 0x4); + val = readl(htpic->base + i * 0x4); + /* Ack all possible pending IRQs */ + writel(GENMASK(31, 0), htpic->base + i * 0x4); + } + + /* Enable 16 vectors for PIC */ + writel(0xffff, htpic->base + HTINT_EN_OFF); +} + +static void htpic_resume(void) +{ + htpic_reg_init(); +} + +struct syscore_ops htpic_syscore_ops = { + .resume = htpic_resume, +}; + +int __init htpic_of_init(struct device_node *node, struct device_node *parent) +{ + unsigned int parent_irq[4]; + int i, err; + int num_parents = 0; + + if (htpic) { + pr_err("loongson-htpic: Only one HTPIC is allowed in the system\n"); + return -ENODEV; + } + + htpic = kzalloc(sizeof(*htpic), GFP_KERNEL); + if (!htpic) { + err = -ENOMEM; + goto out_free; + } + + htpic->base = of_iomap(node, 0); + if (!htpic->base) { + err = -ENODEV; + goto out_free; + } + + htpic->domain = __init_i8259_irqs(node); + if (!htpic->domain) { + pr_err("loongson-htpic: Failed to initialize i8259 IRQs\n"); + err = -ENOMEM; + goto out_iounmap; + } + + /* Interrupt may come from any of the 4 interrupt line */ + for (i = 0; i < HTPIC_MAX_PARENT_IRQ; i++) { + parent_irq[i] = irq_of_parse_and_map(node, i); + if (parent_irq[i] <= 0) + break; + + num_parents++; + } + + if (!num_parents) { + pr_err("loongson-htpic: Failed to get parent irqs\n"); + err = -ENODEV; + goto out_remove_domain; + } + + htpic_reg_init(); + + for (i = 0; i < num_parents; i++) { + irq_set_chained_handler_and_data(parent_irq[i], + htpic_irq_dispatch, htpic); + } + + register_syscore_ops(&htpic_syscore_ops); + + return 0; + +out_remove_domain: + irq_domain_remove(htpic->domain); +out_iounmap: + iounmap(htpic->base); +out_free: + kfree(htpic); + return err; +} + +IRQCHIP_DECLARE(loongson_htpic, "loongson,htpic-1.0", htpic_of_init); |