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
pirq_get_next_free_irq(struct udevice * dev,u8 * pirq,u16 bitmap,bool irq_already_routed[])14 static u8 pirq_get_next_free_irq(struct udevice *dev, u8 *pirq, u16 bitmap,
15 bool irq_already_routed[])
16 {
17 int i, link;
18 u8 irq = 0;
19
20 /* IRQ sharing starts from IRQ#3 */
21 for (i = 3; i < 16; i++) {
22 /* Can we assign this IRQ? */
23 if (!((bitmap >> i) & 1))
24 continue;
25
26 /* We can, now let's assume we can use this IRQ */
27 irq = i;
28
29 /* Have we already routed it? */
30 if (irq_already_routed[irq])
31 continue;
32
33 for (link = 0; link < CONFIG_MAX_PIRQ_LINKS; link++) {
34 if (pirq_check_irq_routed(dev, link, irq)) {
35 irq_already_routed[irq] = true;
36 break;
37 }
38 }
39
40 /* If it's not yet routed, use it */
41 if (!irq_already_routed[irq]) {
42 irq_already_routed[irq] = true;
43 break;
44 }
45
46 /* But if it was already routed, try the next one */
47 }
48
49 /* Now we get our IRQ */
50 return irq;
51 }
52
pirq_route_irqs(struct udevice * dev,struct irq_info * irq,int num)53 void pirq_route_irqs(struct udevice *dev, struct irq_info *irq, int num)
54 {
55 unsigned char irq_slot[MAX_INTX_ENTRIES];
56 unsigned char pirq[CONFIG_MAX_PIRQ_LINKS];
57 bool irq_already_routed[16];
58 int i, intx;
59
60 memset(pirq, 0, CONFIG_MAX_PIRQ_LINKS);
61 memset(irq_already_routed, '\0', sizeof(irq_already_routed));
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(dev, link);
84
85 /* yet not routed */
86 if (!pirq[link]) {
87 irq = pirq_get_next_free_irq(dev, pirq, bitmap,
88 irq_already_routed);
89 pirq[link] = irq;
90 } else {
91 irq = pirq[link];
92 }
93
94 debug("IRQ: %d\n", irq);
95 irq_slot[intx] = irq;
96
97 /* Assign IRQ in the interrupt router */
98 pirq_assign_irq(dev, link, irq);
99 }
100
101 /* Bus, device, slots IRQs for {A,B,C,D} */
102 pci_assign_irqs(irq->bus, irq->devfn >> 3, 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
copy_pirq_routing_table(u32 addr,struct irq_routing_table * rt)111 u32 copy_pirq_routing_table(u32 addr, struct irq_routing_table *rt)
112 {
113 struct irq_routing_table *rom_rt;
114
115 /* Align the table to be 16 byte aligned */
116 addr = ALIGN(addr, 16);
117
118 debug("Copying Interrupt Routing Table to 0x%x\n", addr);
119 memcpy((void *)(uintptr_t)addr, rt, rt->size);
120
121 /*
122 * We do the sanity check here against the copied table after memcpy,
123 * as something might go wrong after the memcpy, which is normally
124 * due to the F segment decode is not turned on to systeam RAM.
125 */
126 rom_rt = (struct irq_routing_table *)(uintptr_t)addr;
127 if (rom_rt->signature != PIRQ_SIGNATURE ||
128 rom_rt->version != PIRQ_VERSION || rom_rt->size % 16) {
129 printf("Interrupt Routing Table not valid\n");
130 return addr;
131 }
132
133 return addr + rt->size;
134 }
135