Hi Greg, PCI folk,
In our hardware situation, the BIOS is unable to store or generate it's PIRQ
table in the F0000h-100000h standard range. This patch adds a pci kernel
parameter, pirqaddr to allow the bootloader (or BIOS based loader) to inform
the kernel where the PIRQ table got stored. A beneficial side-effect is that,
if one's BIOS uses a static address each time for it's PIRQ table, then
pirqaddr can be used to avoid the $pirq search through that address block each
time at boot for normal PIRQ BIOSes.
Signed-off-by: Jaya Kumar <[EMAIL PROTECTED]>
diff -uprN -X dontdiff linux-2.6.11.2-vanilla/arch/i386/pci/common.c
linux-2.6.11.2/arch/i386/pci/common.c
--- linux-2.6.11.2-vanilla/arch/i386/pci/common.c 2005-03-10
16:31:25.000000000 +0800
+++ linux-2.6.11.2/arch/i386/pci/common.c 2005-03-10 16:56:09.000000000
+0800
@@ -25,6 +25,7 @@ unsigned int pci_probe = PCI_PROBE_BIOS
int pci_routeirq;
int pcibios_last_bus = -1;
+unsigned int pirq_table_addr = 0;
struct pci_bus *pci_root_bus = NULL;
struct pci_raw_ops *raw_pci_ops;
@@ -188,6 +189,9 @@ char * __devinit pcibios_setup(char *st
} else if (!strcmp(str, "biosirq")) {
pci_probe |= PCI_BIOS_IRQ_SCAN;
return NULL;
+ } else if (!strncmp(str, "pirqaddr=", 9)) {
+ pirq_table_addr = simple_strtol(str+9, NULL, 0);
+ return NULL;
}
#endif
#ifdef CONFIG_PCI_DIRECT
diff -uprN -X dontdiff linux-2.6.11.2-vanilla/arch/i386/pci/irq.c
linux-2.6.11.2/arch/i386/pci/irq.c
--- linux-2.6.11.2-vanilla/arch/i386/pci/irq.c 2005-03-10 16:31:25.000000000
+0800
+++ linux-2.6.11.2/arch/i386/pci/irq.c 2005-03-10 20:43:02.479487640 +0800
@@ -58,6 +58,35 @@ struct irq_router_handler {
int (*pcibios_enable_irq)(struct pci_dev *dev) = NULL;
/*
+ * Check passed address for the PCI IRQ Routing Table signature
+ * and perform checksum verification.
+ */
+
+static inline struct irq_routing_table * __init pirq_check_routing_table(u8
*addr)
+{
+ struct irq_routing_table *rt;
+ int i;
+ u8 sum;
+
+ rt = (struct irq_routing_table *) addr;
+ if (rt->signature != PIRQ_SIGNATURE ||
+ rt->version != PIRQ_VERSION ||
+ rt->size % 16 ||
+ rt->size < sizeof(struct irq_routing_table))
+ return NULL;
+ sum = 0;
+ for(i=0; i<rt->size; i++)
+ sum += addr[i];
+ if (!sum) {
+ DBG("PCI: Interrupt Routing Table found at 0x%p\n", rt);
+ return rt;
+ }
+ return NULL;
+}
+
+
+
+/*
* Search 0xf0000 -- 0xfffff for the PCI IRQ Routing Table.
*/
@@ -65,21 +94,16 @@ static struct irq_routing_table * __init
{
u8 *addr;
struct irq_routing_table *rt;
- int i;
- u8 sum;
+ if (pirq_table_addr) {
+ rt = pirq_check_routing_table((u8 *) __va(pirq_table_addr));
+ if (rt) {
+ return rt;
+ }
+ }
for(addr = (u8 *) __va(0xf0000); addr < (u8 *) __va(0x100000); addr +=
16) {
- rt = (struct irq_routing_table *) addr;
- if (rt->signature != PIRQ_SIGNATURE ||
- rt->version != PIRQ_VERSION ||
- rt->size % 16 ||
- rt->size < sizeof(struct irq_routing_table))
- continue;
- sum = 0;
- for(i=0; i<rt->size; i++)
- sum += addr[i];
- if (!sum) {
- DBG("PCI: Interrupt Routing Table found at 0x%p\n", rt);
+ rt = pirq_check_routing_table(addr);
+ if (rt) {
return rt;
}
}
diff -uprN -X dontdiff linux-2.6.11.2-vanilla/arch/i386/pci/pci.h
linux-2.6.11.2/arch/i386/pci/pci.h
--- linux-2.6.11.2-vanilla/arch/i386/pci/pci.h 2005-03-10 16:31:25.000000000
+0800
+++ linux-2.6.11.2/arch/i386/pci/pci.h 2005-03-10 16:52:09.000000000 +0800
@@ -27,6 +27,7 @@
#define PCI_ASSIGN_ALL_BUSSES 0x4000
extern unsigned int pci_probe;
+extern unsigned int pirq_table_addr;
/* pci-i386.c */
diff -uprN -X dontdiff
linux-2.6.11.2-vanilla/Documentation/kernel-parameters.txt
linux-2.6.11.2/Documentation/kernel-parameters.txt
--- linux-2.6.11.2-vanilla/Documentation/kernel-parameters.txt 2005-03-10
16:31:44.000000000 +0800
+++ linux-2.6.11.2/Documentation/kernel-parameters.txt 2005-03-10
16:45:48.000000000 +0800
@@ -967,6 +967,10 @@ running once the system is up.
irqmask=0xMMMM [IA-32] Set a bit mask of IRQs allowed
to be assigned
automatically to PCI devices. You can
make the kernel
exclude IRQs of your ISA cards this way.
+ pirqaddr=0xAAAAA [IA-32] Specify the physical address
+ of the PIRQ table (normally generated
+ by the BIOS) if it is outside the .
+ F0000h-100000h range.
lastbus=N [IA-32] Scan all buses till bus #N. Can
be useful
if the kernel is unable to find your
secondary buses
and you want to tell it explicitly
which ones they are.
-
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