1 #include <linux/seq_file.h> 2 #include <linux/cpumask.h> 3 #include <linux/kernel.h> 4 #include <linux/string.h> 5 #include <linux/errno.h> 6 #include <linux/msi.h> 7 #include <linux/irq.h> 8 #include <linux/pci.h> 9 #include <linux/irqdomain.h> 10 11 #include <asm/hw_irq.h> 12 #include <asm/irq_remapping.h> 13 #include <asm/processor.h> 14 #include <asm/x86_init.h> 15 #include <asm/apic.h> 16 #include <asm/hpet.h> 17 18 #include "irq_remapping.h" 19 20 int irq_remapping_enabled; 21 int irq_remap_broken; 22 int disable_sourceid_checking; 23 int no_x2apic_optout; 24 25 int disable_irq_post = 1; 26 27 static int disable_irq_remap; 28 static struct irq_remap_ops *remap_ops; 29 30 static void irq_remapping_disable_io_apic(void) 31 { 32 /* 33 * With interrupt-remapping, for now we will use virtual wire A 34 * mode, as virtual wire B is little complex (need to configure 35 * both IOAPIC RTE as well as interrupt-remapping table entry). 36 * As this gets called during crash dump, keep this simple for 37 * now. 38 */ 39 if (cpu_has_apic || apic_from_smp_config()) 40 disconnect_bsp_APIC(0); 41 } 42 43 static void __init irq_remapping_modify_x86_ops(void) 44 { 45 x86_io_apic_ops.disable = irq_remapping_disable_io_apic; 46 } 47 48 static __init int setup_nointremap(char *str) 49 { 50 disable_irq_remap = 1; 51 return 0; 52 } 53 early_param("nointremap", setup_nointremap); 54 55 static __init int setup_irqremap(char *str) 56 { 57 if (!str) 58 return -EINVAL; 59 60 while (*str) { 61 if (!strncmp(str, "on", 2)) 62 disable_irq_remap = 0; 63 else if (!strncmp(str, "off", 3)) 64 disable_irq_remap = 1; 65 else if (!strncmp(str, "nosid", 5)) 66 disable_sourceid_checking = 1; 67 else if (!strncmp(str, "no_x2apic_optout", 16)) 68 no_x2apic_optout = 1; 69 70 str += strcspn(str, ","); 71 while (*str == ',') 72 str++; 73 } 74 75 return 0; 76 } 77 early_param("intremap", setup_irqremap); 78 79 void set_irq_remapping_broken(void) 80 { 81 irq_remap_broken = 1; 82 } 83 84 bool irq_remapping_cap(enum irq_remap_cap cap) 85 { 86 if (!remap_ops || disable_irq_post) 87 return 0; 88 89 return (remap_ops->capability & (1 << cap)); 90 } 91 EXPORT_SYMBOL_GPL(irq_remapping_cap); 92 93 int __init irq_remapping_prepare(void) 94 { 95 if (disable_irq_remap) 96 return -ENOSYS; 97 98 if (intel_irq_remap_ops.prepare() == 0) 99 remap_ops = &intel_irq_remap_ops; 100 else if (IS_ENABLED(CONFIG_AMD_IOMMU) && 101 amd_iommu_irq_ops.prepare() == 0) 102 remap_ops = &amd_iommu_irq_ops; 103 else 104 return -ENOSYS; 105 106 return 0; 107 } 108 109 int __init irq_remapping_enable(void) 110 { 111 int ret; 112 113 if (!remap_ops->enable) 114 return -ENODEV; 115 116 ret = remap_ops->enable(); 117 118 if (irq_remapping_enabled) 119 irq_remapping_modify_x86_ops(); 120 121 return ret; 122 } 123 124 void irq_remapping_disable(void) 125 { 126 if (irq_remapping_enabled && remap_ops->disable) 127 remap_ops->disable(); 128 } 129 130 int irq_remapping_reenable(int mode) 131 { 132 if (irq_remapping_enabled && remap_ops->reenable) 133 return remap_ops->reenable(mode); 134 135 return 0; 136 } 137 138 int __init irq_remap_enable_fault_handling(void) 139 { 140 if (!irq_remapping_enabled) 141 return 0; 142 143 if (!remap_ops->enable_faulting) 144 return -ENODEV; 145 146 return remap_ops->enable_faulting(); 147 } 148 149 void panic_if_irq_remap(const char *msg) 150 { 151 if (irq_remapping_enabled) 152 panic(msg); 153 } 154 155 void ir_ack_apic_edge(struct irq_data *data) 156 { 157 ack_APIC_irq(); 158 } 159 160 /** 161 * irq_remapping_get_ir_irq_domain - Get the irqdomain associated with the IOMMU 162 * device serving request @info 163 * @info: interrupt allocation information, used to identify the IOMMU device 164 * 165 * It's used to get parent irqdomain for HPET and IOAPIC irqdomains. 166 * Returns pointer to IRQ domain, or NULL on failure. 167 */ 168 struct irq_domain * 169 irq_remapping_get_ir_irq_domain(struct irq_alloc_info *info) 170 { 171 if (!remap_ops || !remap_ops->get_ir_irq_domain) 172 return NULL; 173 174 return remap_ops->get_ir_irq_domain(info); 175 } 176 177 /** 178 * irq_remapping_get_irq_domain - Get the irqdomain serving the request @info 179 * @info: interrupt allocation information, used to identify the IOMMU device 180 * 181 * There will be one PCI MSI/MSIX irqdomain associated with each interrupt 182 * remapping device, so this interface is used to retrieve the PCI MSI/MSIX 183 * irqdomain serving request @info. 184 * Returns pointer to IRQ domain, or NULL on failure. 185 */ 186 struct irq_domain * 187 irq_remapping_get_irq_domain(struct irq_alloc_info *info) 188 { 189 if (!remap_ops || !remap_ops->get_irq_domain) 190 return NULL; 191 192 return remap_ops->get_irq_domain(info); 193 } 194