From jayalk@intworks.biz Mon Mar 21 20:26:30 2005 Date: Mon, 21 Mar 2005 20:20:42 -0800 From: jayalk@intworks.biz To: gregkh@suse.de Subject: [PATCH 2.6.11.2 1/1] PCI Allow OutOfRange PIRQ table address Cc: linux-kernel@vger.kernel.org, linux-pci@atrey.karlin.mff.cuni.cz Status: RO Content-Length: 5106 Lines: 138 I updated this to remove unnecessary variable initialization, make check_routing be inline only and not __init, switch to strtoul, and formatting fixes as per Randy Dunlap's recommendations. I updated this to change pirq_table_addr to a long, and to add a warning msg if the PIRQ table wasn't found at the specified address, as per thread with Matthew Wilcox. 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 Signed-off-by: Greg Kroah-Hartman Index: gregkh-2.6/arch/i386/pci/common.c =================================================================== --- gregkh-2.6.orig/arch/i386/pci/common.c 2005-03-01 23:38:07.000000000 -0800 +++ gregkh-2.6/arch/i386/pci/common.c 2005-04-07 17:16:34.000000000 -0700 @@ -25,7 +25,8 @@ int pci_routeirq; int pcibios_last_bus = -1; -struct pci_bus *pci_root_bus = NULL; +unsigned long pirq_table_addr; +struct pci_bus *pci_root_bus; struct pci_raw_ops *raw_pci_ops; static int pci_read(struct pci_bus *bus, unsigned int devfn, int where, int size, u32 *value) @@ -188,6 +189,9 @@ } else if (!strcmp(str, "biosirq")) { pci_probe |= PCI_BIOS_IRQ_SCAN; return NULL; + } else if (!strncmp(str, "pirqaddr=", 9)) { + pirq_table_addr = simple_strtoul(str+9, NULL, 0); + return NULL; } #endif #ifdef CONFIG_PCI_DIRECT Index: gregkh-2.6/arch/i386/pci/irq.c =================================================================== --- gregkh-2.6.orig/arch/i386/pci/irq.c 2005-04-06 11:47:46.000000000 -0700 +++ gregkh-2.6/arch/i386/pci/irq.c 2005-04-07 17:16:34.000000000 -0700 @@ -58,6 +58,35 @@ 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 * 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. */ @@ -65,23 +94,17 @@ { 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; + printk(KERN_WARNING "PCI: PIRQ table NOT found at pirqaddr\n"); + } 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; isize; 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; - } } return NULL; } Index: gregkh-2.6/arch/i386/pci/pci.h =================================================================== --- gregkh-2.6.orig/arch/i386/pci/pci.h 2005-03-01 23:38:10.000000000 -0800 +++ gregkh-2.6/arch/i386/pci/pci.h 2005-04-07 17:16:34.000000000 -0700 @@ -27,6 +27,7 @@ #define PCI_ASSIGN_ALL_BUSSES 0x4000 extern unsigned int pci_probe; +extern unsigned long pirq_table_addr; /* pci-i386.c */ Index: gregkh-2.6/Documentation/kernel-parameters.txt =================================================================== --- gregkh-2.6.orig/Documentation/kernel-parameters.txt 2005-04-06 11:47:45.000000000 -0700 +++ gregkh-2.6/Documentation/kernel-parameters.txt 2005-04-07 17:16:34.000000000 -0700 @@ -1019,6 +1019,10 @@ 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.