pirq_routing: Allow routing with more than 4 PIRQ links
pirq_routing_irqs assumed that only four links are available for PIRQ
routing, INTA to INTD. Some chipsets provide more, up to INTH.
When pirq_routing_irqs found a link number greater than 4 in the pirq table,
it would not assign that IRQ. This is a shame, as it limits the flexibility
of routing IRQs.
Make the maximum number of links a Kconfig variable, and modify the code to
respect it. This works beatifully on the VX900, which provides 8 routable
interrupts.
While we're at it, also refactor pirq_routing_irqs, and add some much
needed comments.
Rename pirq_routing_irqs to pirq_route_irqs to demistify the role of this
function.
The copyrights added were determined from git log filename.
Change-Id: I4b565315404c65b871406f616474e2cc9e6e013e
Signed-off-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
Reviewed-on: http://review.coreboot.org/1482
Tested-by: build bot (Jenkins)
diff --git a/src/arch/x86/boot/pirq_routing.c b/src/arch/x86/boot/pirq_routing.c
index bb8a7b6..357500c 100644
--- a/src/arch/x86/boot/pirq_routing.c
+++ b/src/arch/x86/boot/pirq_routing.c
@@ -1,3 +1,22 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (C) 2012 Alexandru Gagniuc <mr.nuke.me@gmail.com>
+ * Copyright (C) 2010 Stefan Reinauer <stepan@coreboot.org>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
#include <console/console.h>
#include <arch/pirq_routing.h>
#include <string.h>
@@ -92,18 +111,50 @@
#if CONFIG_DEBUG_PIRQ
verify_copy_pirq_routing_table(addr);
#endif
- pirq_routing_irqs(addr);
+ pirq_route_irqs(addr);
return addr + intel_irq_routing_table.size;
}
#if CONFIG_PIRQ_ROUTE
-void pirq_routing_irqs(unsigned long addr)
+static u8 pirq_get_next_free_irq(u8* pirq, u16 bitmap)
{
- int i, j, k, num_entries;
- unsigned char irq_slot[4];
- unsigned char pirq[4] = {0, 0, 0, 0};
+ int i, link;
+ u8 irq = 0;
+ for (i = 2; i <= 15; i++)
+ {
+ /* Can we assign this IRQ ? */
+ if (!((bitmap >> i) & 1))
+ continue;
+ /* We can, Now let's assume we can use this IRQ */
+ irq = i;
+ /* And assume we have not yet routed it */
+ int already_routed = 0;
+ /* Have we already routed it ? */
+ for(link = 0; link < CONFIG_MAX_PIRQ_LINKS; link++) {
+ if (pirq[link] == irq) {
+ already_routed = 1;
+ break;
+ }
+ }
+ /* If it's not yet routed, use it */
+ if(!already_routed)
+ break;
+ /* But if it was already routed, try the next one */
+ continue;
+ }
+ /* Now we got our IRQ */
+ return irq;
+}
+
+void pirq_route_irqs(unsigned long addr)
+{
+ int i, intx, num_entries;
+ unsigned char irq_slot[MAX_INTX_ENTRIES];
+ unsigned char pirq[CONFIG_MAX_PIRQ_LINKS];
struct irq_routing_table *pirq_tbl;
+ memset(pirq, 0, CONFIG_MAX_PIRQ_LINKS);
+
pirq_tbl = (struct irq_routing_table *)(addr);
num_entries = (pirq_tbl->size - 32) / 16;
@@ -113,37 +164,26 @@
printk(BIOS_DEBUG, "PIRQ Entry %d Dev/Fn: %X Slot: %d\n", i,
pirq_tbl->slots[i].devfn >> 3, pirq_tbl->slots[i].slot);
- for (j = 0; j < 4; j++) {
+ for (intx = 0; intx < MAX_INTX_ENTRIES; intx++) {
- int link = pirq_tbl->slots[i].irq[j].link;
- int bitmap = pirq_tbl->slots[i].irq[j].bitmap;
+ int link = pirq_tbl->slots[i].irq[intx].link;
+ int bitmap = pirq_tbl->slots[i].irq[intx].bitmap;
int irq = 0;
printk(BIOS_DEBUG, "INT: %c link: %x bitmap: %x ",
- 'A' + j, link, bitmap);
+ 'A' + intx, link, bitmap);
- if (!bitmap|| !link || link > 4) {
+ if (!bitmap|| !link || link > CONFIG_MAX_PIRQ_LINKS) {
printk(BIOS_DEBUG, "not routed\n");
- irq_slot[j] = irq;
+ irq_slot[intx] = irq;
continue;
}
/* yet not routed */
- if (!pirq[link - 1]) {
-
- for (k = 2; k <= 15; k++) {
-
- if (!((bitmap >> k) & 1))
- continue;
-
- irq = k;
-
- /* yet not routed */
- if (pirq[0] != irq && pirq[1] != irq && pirq[2] != irq && pirq[3] != irq)
- break;
- }
-
+ if (!pirq[link - 1])
+ {
+ irq = pirq_get_next_free_irq(pirq, bitmap);
if (irq)
pirq[link - 1] = irq;
}
@@ -151,7 +191,7 @@
irq = pirq[link - 1];
printk(BIOS_DEBUG, "IRQ: %d\n", irq);
- irq_slot[j] = irq;
+ irq_slot[intx] = irq;
}
/* Bus, device, slots IRQs for {A,B,C,D}. */
@@ -159,10 +199,8 @@
pirq_tbl->slots[i].devfn >> 3, irq_slot);
}
- printk(BIOS_DEBUG, "PIRQ1: %d\n", pirq[0]);
- printk(BIOS_DEBUG, "PIRQ2: %d\n", pirq[1]);
- printk(BIOS_DEBUG, "PIRQ3: %d\n", pirq[2]);
- printk(BIOS_DEBUG, "PIRQ4: %d\n", pirq[3]);
+ for(i = 0; i < CONFIG_MAX_PIRQ_LINKS; i++)
+ printk(BIOS_DEBUG, "PIRQ%c: %d\n", i + 'A', pirq[i]);
pirq_assign_irqs(pirq);
}