diff options
Diffstat (limited to 'drivers/irqchip/irq-loongarch-cpu.c')
| -rw-r--r-- | drivers/irqchip/irq-loongarch-cpu.c | 154 |
1 files changed, 154 insertions, 0 deletions
diff --git a/drivers/irqchip/irq-loongarch-cpu.c b/drivers/irqchip/irq-loongarch-cpu.c new file mode 100644 index 000000000..fdec3e9cf --- /dev/null +++ b/drivers/irqchip/irq-loongarch-cpu.c @@ -0,0 +1,154 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2020-2022 Loongson Technology Corporation Limited + */ + +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/interrupt.h> +#include <linux/irq.h> +#include <linux/irqchip.h> +#include <linux/irqdomain.h> + +#include <asm/loongarch.h> +#include <asm/setup.h> + +static struct irq_domain *irq_domain; +struct fwnode_handle *cpuintc_handle; + +static u32 lpic_gsi_to_irq(u32 gsi) +{ + /* Only pch irqdomain transferring is required for LoongArch. */ + if (gsi >= GSI_MIN_PCH_IRQ && gsi <= GSI_MAX_PCH_IRQ) + return acpi_register_gsi(NULL, gsi, ACPI_LEVEL_SENSITIVE, ACPI_ACTIVE_HIGH); + + return 0; +} + +static struct fwnode_handle *lpic_get_gsi_domain_id(u32 gsi) +{ + int id; + struct fwnode_handle *domain_handle = NULL; + + switch (gsi) { + case GSI_MIN_CPU_IRQ ... GSI_MAX_CPU_IRQ: + if (liointc_handle) + domain_handle = liointc_handle; + break; + + case GSI_MIN_LPC_IRQ ... GSI_MAX_LPC_IRQ: + if (pch_lpc_handle) + domain_handle = pch_lpc_handle; + break; + + case GSI_MIN_PCH_IRQ ... GSI_MAX_PCH_IRQ: + id = find_pch_pic(gsi); + if (id >= 0 && pch_pic_handle[id]) + domain_handle = pch_pic_handle[id]; + break; + } + + return domain_handle; +} + +static void mask_loongarch_irq(struct irq_data *d) +{ + clear_csr_ecfg(ECFGF(d->hwirq)); +} + +static void unmask_loongarch_irq(struct irq_data *d) +{ + set_csr_ecfg(ECFGF(d->hwirq)); +} + +static struct irq_chip cpu_irq_controller = { + .name = "CPUINTC", + .irq_mask = mask_loongarch_irq, + .irq_unmask = unmask_loongarch_irq, +}; + +static void handle_cpu_irq(struct pt_regs *regs) +{ + int hwirq; + unsigned int estat = read_csr_estat() & CSR_ESTAT_IS; + + while ((hwirq = ffs(estat))) { + estat &= ~BIT(hwirq - 1); + generic_handle_domain_irq(irq_domain, hwirq - 1); + } +} + +static int loongarch_cpu_intc_map(struct irq_domain *d, unsigned int irq, + irq_hw_number_t hwirq) +{ + irq_set_noprobe(irq); + irq_set_chip_and_handler(irq, &cpu_irq_controller, handle_percpu_irq); + + return 0; +} + +static const struct irq_domain_ops loongarch_cpu_intc_irq_domain_ops = { + .map = loongarch_cpu_intc_map, + .xlate = irq_domain_xlate_onecell, +}; + +static int __init liointc_parse_madt(union acpi_subtable_headers *header, + const unsigned long end) +{ + struct acpi_madt_lio_pic *liointc_entry = (struct acpi_madt_lio_pic *)header; + + return liointc_acpi_init(irq_domain, liointc_entry); +} + +static int __init eiointc_parse_madt(union acpi_subtable_headers *header, + const unsigned long end) +{ + struct acpi_madt_eio_pic *eiointc_entry = (struct acpi_madt_eio_pic *)header; + + return eiointc_acpi_init(irq_domain, eiointc_entry); +} + +static int __init acpi_cascade_irqdomain_init(void) +{ + int r; + + r = acpi_table_parse_madt(ACPI_MADT_TYPE_LIO_PIC, liointc_parse_madt, 0); + if (r < 0) + return r; + + r = acpi_table_parse_madt(ACPI_MADT_TYPE_EIO_PIC, eiointc_parse_madt, 0); + if (r < 0) + return r; + + return 0; +} + +static int __init cpuintc_acpi_init(union acpi_subtable_headers *header, + const unsigned long end) +{ + int ret; + + if (irq_domain) + return 0; + + /* Mask interrupts. */ + clear_csr_ecfg(ECFG0_IM); + clear_csr_estat(ESTATF_IP); + + cpuintc_handle = irq_domain_alloc_named_fwnode("CPUINTC"); + irq_domain = irq_domain_create_linear(cpuintc_handle, EXCCODE_INT_NUM, + &loongarch_cpu_intc_irq_domain_ops, NULL); + + if (!irq_domain) + panic("Failed to add irqdomain for LoongArch CPU"); + + set_handle_irq(&handle_cpu_irq); + acpi_set_irq_model(ACPI_IRQ_MODEL_LPIC, lpic_get_gsi_domain_id); + acpi_set_gsi_to_irq_fallback(lpic_gsi_to_irq); + ret = acpi_cascade_irqdomain_init(); + + return ret; +} + +IRQCHIP_ACPI_DECLARE(cpuintc_v1, ACPI_MADT_TYPE_CORE_PIC, + NULL, ACPI_MADT_CORE_PIC_VERSION_V1, cpuintc_acpi_init); |