1 /* 2 * Copyright (C) 2015, Bin Meng <bmeng.cn@gmail.com> 3 * 4 * Part of this file is ported from coreboot src/arch/x86/boot/pirq_routing.c 5 * 6 * SPDX-License-Identifier: GPL-2.0+ 7 */ 8 9 #include <common.h> 10 #include <pci.h> 11 #include <asm/pci.h> 12 #include <asm/pirq_routing.h> 13 #include <asm/tables.h> 14 15 static bool irq_already_routed[16]; 16 17 static u8 pirq_get_next_free_irq(u8 *pirq, u16 bitmap) 18 { 19 int i, link; 20 u8 irq = 0; 21 22 /* IRQ sharing starts from IRQ#3 */ 23 for (i = 3; i < 16; i++) { 24 /* Can we assign this IRQ? */ 25 if (!((bitmap >> i) & 1)) 26 continue; 27 28 /* We can, now let's assume we can use this IRQ */ 29 irq = i; 30 31 /* Have we already routed it? */ 32 if (irq_already_routed[irq]) 33 continue; 34 35 for (link = 0; link < CONFIG_MAX_PIRQ_LINKS; link++) { 36 if (pirq_check_irq_routed(link, irq)) { 37 irq_already_routed[irq] = true; 38 break; 39 } 40 } 41 42 /* If it's not yet routed, use it */ 43 if (!irq_already_routed[irq]) { 44 irq_already_routed[irq] = true; 45 break; 46 } 47 48 /* But if it was already routed, try the next one */ 49 } 50 51 /* Now we get our IRQ */ 52 return irq; 53 } 54 55 void pirq_route_irqs(struct irq_info *irq, int num) 56 { 57 unsigned char irq_slot[MAX_INTX_ENTRIES]; 58 unsigned char pirq[CONFIG_MAX_PIRQ_LINKS]; 59 int i, intx; 60 61 memset(pirq, 0, CONFIG_MAX_PIRQ_LINKS); 62 63 /* Set PCI IRQs */ 64 for (i = 0; i < num; i++) { 65 debug("PIRQ Entry %d Dev: %d.%x.%d\n", i, 66 irq->bus, irq->devfn >> 3, irq->devfn & 7); 67 68 for (intx = 0; intx < MAX_INTX_ENTRIES; intx++) { 69 int link = irq->irq[intx].link; 70 int bitmap = irq->irq[intx].bitmap; 71 int irq = 0; 72 73 debug("INT%c link: %x bitmap: %x ", 74 'A' + intx, link, bitmap); 75 76 if (!bitmap || !link) { 77 debug("not routed\n"); 78 irq_slot[intx] = irq; 79 continue; 80 } 81 82 /* translate link value to link number */ 83 link = pirq_translate_link(link); 84 85 /* yet not routed */ 86 if (!pirq[link]) { 87 irq = pirq_get_next_free_irq(pirq, bitmap); 88 pirq[link] = irq; 89 } else { 90 irq = pirq[link]; 91 } 92 93 debug("IRQ: %d\n", irq); 94 irq_slot[intx] = irq; 95 96 /* Assign IRQ in the interrupt router */ 97 pirq_assign_irq(link, irq); 98 } 99 100 /* Bus, device, slots IRQs for {A,B,C,D} */ 101 pci_assign_irqs(irq->bus, irq->devfn >> 3, irq->devfn & 7, 102 irq_slot); 103 104 irq++; 105 } 106 107 for (i = 0; i < CONFIG_MAX_PIRQ_LINKS; i++) 108 debug("PIRQ%c: %d\n", 'A' + i, pirq[i]); 109 } 110 111 u32 copy_pirq_routing_table(u32 addr, struct irq_routing_table *rt) 112 { 113 struct irq_routing_table *rom_rt; 114 115 /* Fix up the table checksum */ 116 rt->checksum = table_compute_checksum(rt, rt->size); 117 118 /* Align the table to be 16 byte aligned */ 119 addr = ALIGN(addr, 16); 120 121 debug("Copying Interrupt Routing Table to 0x%x\n", addr); 122 memcpy((void *)addr, rt, rt->size); 123 124 /* 125 * We do the sanity check here against the copied table after memcpy, 126 * as something might go wrong after the memcpy, which is normally 127 * due to the F segment decode is not turned on to systeam RAM. 128 */ 129 rom_rt = (struct irq_routing_table *)addr; 130 if (rom_rt->signature != PIRQ_SIGNATURE || 131 rom_rt->version != PIRQ_VERSION || rom_rt->size % 16) { 132 printf("Interrupt Routing Table not valid\n"); 133 return addr; 134 } 135 136 return addr + rt->size; 137 } 138