1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Copyright (C) 2020-2022 Loongson Technology Corporation Limited 4 */ 5 6 #include <linux/init.h> 7 #include <linux/kernel.h> 8 #include <linux/interrupt.h> 9 #include <linux/irq.h> 10 #include <linux/irqchip.h> 11 #include <linux/irqdomain.h> 12 13 #include <asm/loongarch.h> 14 #include <asm/setup.h> 15 16 static struct irq_domain *irq_domain; 17 struct fwnode_handle *cpuintc_handle; 18 19 static u32 lpic_gsi_to_irq(u32 gsi) 20 { 21 /* Only pch irqdomain transferring is required for LoongArch. */ 22 if (gsi >= GSI_MIN_PCH_IRQ && gsi <= GSI_MAX_PCH_IRQ) 23 return acpi_register_gsi(NULL, gsi, ACPI_LEVEL_SENSITIVE, ACPI_ACTIVE_HIGH); 24 25 return 0; 26 } 27 28 static struct fwnode_handle *lpic_get_gsi_domain_id(u32 gsi) 29 { 30 int id; 31 struct fwnode_handle *domain_handle = NULL; 32 33 switch (gsi) { 34 case GSI_MIN_CPU_IRQ ... GSI_MAX_CPU_IRQ: 35 if (liointc_handle) 36 domain_handle = liointc_handle; 37 break; 38 39 case GSI_MIN_LPC_IRQ ... GSI_MAX_LPC_IRQ: 40 if (pch_lpc_handle) 41 domain_handle = pch_lpc_handle; 42 break; 43 44 case GSI_MIN_PCH_IRQ ... GSI_MAX_PCH_IRQ: 45 id = find_pch_pic(gsi); 46 if (id >= 0 && pch_pic_handle[id]) 47 domain_handle = pch_pic_handle[id]; 48 break; 49 } 50 51 return domain_handle; 52 } 53 54 static void mask_loongarch_irq(struct irq_data *d) 55 { 56 clear_csr_ecfg(ECFGF(d->hwirq)); 57 } 58 59 static void unmask_loongarch_irq(struct irq_data *d) 60 { 61 set_csr_ecfg(ECFGF(d->hwirq)); 62 } 63 64 static struct irq_chip cpu_irq_controller = { 65 .name = "CPUINTC", 66 .irq_mask = mask_loongarch_irq, 67 .irq_unmask = unmask_loongarch_irq, 68 }; 69 70 static void handle_cpu_irq(struct pt_regs *regs) 71 { 72 int hwirq; 73 unsigned int estat = read_csr_estat() & CSR_ESTAT_IS; 74 75 while ((hwirq = ffs(estat))) { 76 estat &= ~BIT(hwirq - 1); 77 generic_handle_domain_irq(irq_domain, hwirq - 1); 78 } 79 } 80 81 static int loongarch_cpu_intc_map(struct irq_domain *d, unsigned int irq, 82 irq_hw_number_t hwirq) 83 { 84 irq_set_noprobe(irq); 85 irq_set_chip_and_handler(irq, &cpu_irq_controller, handle_percpu_irq); 86 87 return 0; 88 } 89 90 static const struct irq_domain_ops loongarch_cpu_intc_irq_domain_ops = { 91 .map = loongarch_cpu_intc_map, 92 .xlate = irq_domain_xlate_onecell, 93 }; 94 95 static int __init 96 liointc_parse_madt(union acpi_subtable_headers *header, 97 const unsigned long end) 98 { 99 struct acpi_madt_lio_pic *liointc_entry = (struct acpi_madt_lio_pic *)header; 100 101 return liointc_acpi_init(irq_domain, liointc_entry); 102 } 103 104 static int __init 105 eiointc_parse_madt(union acpi_subtable_headers *header, 106 const unsigned long end) 107 { 108 struct acpi_madt_eio_pic *eiointc_entry = (struct acpi_madt_eio_pic *)header; 109 110 return eiointc_acpi_init(irq_domain, eiointc_entry); 111 } 112 113 static int __init acpi_cascade_irqdomain_init(void) 114 { 115 acpi_table_parse_madt(ACPI_MADT_TYPE_LIO_PIC, 116 liointc_parse_madt, 0); 117 acpi_table_parse_madt(ACPI_MADT_TYPE_EIO_PIC, 118 eiointc_parse_madt, 0); 119 return 0; 120 } 121 122 static int __init cpuintc_acpi_init(union acpi_subtable_headers *header, 123 const unsigned long end) 124 { 125 if (irq_domain) 126 return 0; 127 128 /* Mask interrupts. */ 129 clear_csr_ecfg(ECFG0_IM); 130 clear_csr_estat(ESTATF_IP); 131 132 cpuintc_handle = irq_domain_alloc_named_fwnode("CPUINTC"); 133 irq_domain = irq_domain_create_linear(cpuintc_handle, EXCCODE_INT_NUM, 134 &loongarch_cpu_intc_irq_domain_ops, NULL); 135 136 if (!irq_domain) 137 panic("Failed to add irqdomain for LoongArch CPU"); 138 139 set_handle_irq(&handle_cpu_irq); 140 acpi_set_irq_model(ACPI_IRQ_MODEL_LPIC, lpic_get_gsi_domain_id); 141 acpi_set_gsi_to_irq_fallback(lpic_gsi_to_irq); 142 acpi_cascade_irqdomain_init(); 143 144 return 0; 145 } 146 147 IRQCHIP_ACPI_DECLARE(cpuintc_v1, ACPI_MADT_TYPE_CORE_PIC, 148 NULL, ACPI_MADT_CORE_PIC_VERSION_V1, cpuintc_acpi_init); 149