u-boot-brain/arch/x86/lib/pirq_routing.c
Bin Meng 10d569ea1a x86: Fix up PIRQ routing table checksum earlier
PIRQ routing table checksum is fixed up in copy_pirq_routing_table(),
which is fine if we only write the configuration table once. But with
the SeaBIOS case, when we write the table for the second time, the
checksum will be fixed up to zero per the checksum algorithm, which
is caused by the checksum field not being zero before fix up, since
the checksum has already been calculated in the first run.

To fix this, move the checksum fixup to create_pirq_routing_table(),
so that copy_pirq_routing_table() only does what its function name
suggests: copy the table to somewhere else.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
2016-05-23 15:18:00 +08:00

133 lines
3.0 KiB
C

/*
* Copyright (C) 2015, Bin Meng <bmeng.cn@gmail.com>
*
* Part of this file is ported from coreboot src/arch/x86/boot/pirq_routing.c
*
* SPDX-License-Identifier: GPL-2.0+
*/
#include <common.h>
#include <pci.h>
#include <asm/pci.h>
#include <asm/pirq_routing.h>
static bool irq_already_routed[16];
static u8 pirq_get_next_free_irq(struct udevice *dev, u8 *pirq, u16 bitmap)
{
int i, link;
u8 irq = 0;
/* IRQ sharing starts from IRQ#3 */
for (i = 3; i < 16; i++) {
/* Can we assign this IRQ? */
if (!((bitmap >> i) & 1))
continue;
/* We can, now let's assume we can use this IRQ */
irq = i;
/* Have we already routed it? */
if (irq_already_routed[irq])
continue;
for (link = 0; link < CONFIG_MAX_PIRQ_LINKS; link++) {
if (pirq_check_irq_routed(dev, link, irq)) {
irq_already_routed[irq] = true;
break;
}
}
/* If it's not yet routed, use it */
if (!irq_already_routed[irq]) {
irq_already_routed[irq] = true;
break;
}
/* But if it was already routed, try the next one */
}
/* Now we get our IRQ */
return irq;
}
void pirq_route_irqs(struct udevice *dev, struct irq_info *irq, int num)
{
unsigned char irq_slot[MAX_INTX_ENTRIES];
unsigned char pirq[CONFIG_MAX_PIRQ_LINKS];
int i, intx;
memset(pirq, 0, CONFIG_MAX_PIRQ_LINKS);
/* Set PCI IRQs */
for (i = 0; i < num; i++) {
debug("PIRQ Entry %d Dev: %d.%x.%d\n", i,
irq->bus, irq->devfn >> 3, irq->devfn & 7);
for (intx = 0; intx < MAX_INTX_ENTRIES; intx++) {
int link = irq->irq[intx].link;
int bitmap = irq->irq[intx].bitmap;
int irq = 0;
debug("INT%c link: %x bitmap: %x ",
'A' + intx, link, bitmap);
if (!bitmap || !link) {
debug("not routed\n");
irq_slot[intx] = irq;
continue;
}
/* translate link value to link number */
link = pirq_translate_link(dev, link);
/* yet not routed */
if (!pirq[link]) {
irq = pirq_get_next_free_irq(dev, pirq, bitmap);
pirq[link] = irq;
} else {
irq = pirq[link];
}
debug("IRQ: %d\n", irq);
irq_slot[intx] = irq;
/* Assign IRQ in the interrupt router */
pirq_assign_irq(dev, link, irq);
}
/* Bus, device, slots IRQs for {A,B,C,D} */
pci_assign_irqs(irq->bus, irq->devfn >> 3, irq_slot);
irq++;
}
for (i = 0; i < CONFIG_MAX_PIRQ_LINKS; i++)
debug("PIRQ%c: %d\n", 'A' + i, pirq[i]);
}
u32 copy_pirq_routing_table(u32 addr, struct irq_routing_table *rt)
{
struct irq_routing_table *rom_rt;
/* Align the table to be 16 byte aligned */
addr = ALIGN(addr, 16);
debug("Copying Interrupt Routing Table to 0x%x\n", addr);
memcpy((void *)addr, rt, rt->size);
/*
* We do the sanity check here against the copied table after memcpy,
* as something might go wrong after the memcpy, which is normally
* due to the F segment decode is not turned on to systeam RAM.
*/
rom_rt = (struct irq_routing_table *)addr;
if (rom_rt->signature != PIRQ_SIGNATURE ||
rom_rt->version != PIRQ_VERSION || rom_rt->size % 16) {
printf("Interrupt Routing Table not valid\n");
return addr;
}
return addr + rt->size;
}