On Tue, 2007-02-13 at 10:37 -0800, Luck, Tony wrote: > > + pci_read_config_byte(dev, PCI_CLASS_PROG, &tmp8); > > + mask = (1 << 2) | (1 << 0); > > + if ((tmp8 & mask) == mask) > > Are there no symbolic defines for these bits? No. > If there are, then > use them. If not, then does it really help readability to assemble > the bits by hand? Why not just use: > > if ((tmp8 & 5) == 5) Ok, I will change it. > > -Tony > > P.S. The BIOS per se isn't to blame here. If you dump pci space > from the EFI prompt (use "pci 0 1f 1") you'll see that the BIOS really > hasn't initialized the BARs at all.Perhaps some stuff in ACPI sets > them up (wrongly)? I checked the BARs under EFI prompt. BAR 5 is 0 which looks like not initialized by BIOS. But my opinion is BIOS really initiates BAR 5 as 0, or it should change it to non-zero but it doesn't. Function pci_read_bases reads all 6 bars from the device configuraton space and initiates dev->resource[]. When a BAR=0, if the sz (size) is not zero, the resource[].start will be set to 0 and resource[].end will be set to sz. resource[].flag is IORESOURCE_MEM. Such data is realy the same thing we could see under /sys/devices/_bus_/_deviceid_/resource after kernel boot. That behavior is also consistent with what Alan replied on linux-ide maillist. Below is the new patch. Thank Tony. --- If ide controllers are at legacy mode, only the 4th BAR is needed, so some BIOS initiate other BAR with incorrect value. ata/ata_piix calls pci_enable_device on the ide controller, which will check BAR resources. If the BAR resource values are incorrect, pci_enable_device will fail, and ata/ata_piix couldn't attach the ide controller. Below patch against 2.6.20 creates a quirk to correct the bad BAR resources for a special ide controller which is popular on tiger-4. Signed-off-by: Zhang Yanmin <yanmin.zhang@xxxxxxxxx> --- --- linux-2.6.20/arch/ia64/kernel/quirks.c 1969-12-31 19:00:00.000000000 -0500 +++ linux-2.6.20_fix/arch/ia64/kernel/quirks.c 2007-02-13 13:56:34.000000000 -0500 @@ -0,0 +1,45 @@ +/* + * This file contains work-arounds for ia64 platform bugs. + */ +#include <linux/pci.h> + +/* + * quirk_intel_ide_controller: If an ide/ata controller is + * at legacy mode, BIOS might initiates BAR(bar 0~3 and 5) + * with incorrect value. This quirk will reset the incorrect + * value to 0. + */ +static void __devinit quirk_intel_ide_controller(struct pci_dev *dev) +{ + unsigned int pos; + struct resource *res; + int fixed = 0; + u8 tmp8; + + if ((dev->class >> 8) != PCI_CLASS_STORAGE_IDE) + return; + + /* TODO: What if one channel is in native mode ... */ + pci_read_config_byte(dev, PCI_CLASS_PROG, &tmp8); + if ((tmp8 & 5) == 5) + return; + + for( pos = 0; pos < 6; pos ++ ) { + res = &dev->resource[pos]; + if (!(res->flags & (IORESOURCE_IO | IORESOURCE_MEM))) + continue; + + if (!res->start && res->end) { + res->start = res->end = 0; + res->flags = 0; + fixed = 1; + } + } + if (fixed) + printk(KERN_WARNING + "PCI device %s: BIOS resource configuration fixed.\n", + pci_name(dev)); +} + +DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801DB_11, quirk_intel_ide_controller); + --- linux-2.6.20/arch/ia64/kernel/Makefile 2007-02-08 02:13:41.000000000 -0500 +++ linux-2.6.20_fix/arch/ia64/kernel/Makefile 2007-02-12 09:49:39.000000000 -0500 @@ -33,6 +33,7 @@ obj-$(CONFIG_CRASH_DUMP) += crash_dump.o obj-$(CONFIG_IA64_UNCACHED_ALLOCATOR) += uncached.o obj-$(CONFIG_AUDIT) += audit.o obj-$(CONFIG_PCI_MSI) += msi_ia64.o +obj-$(CONFIG_PCI) += quirks.o mca_recovery-y += mca_drv.o mca_drv_asm.o obj-$(CONFIG_IA64_ESI) += esi.o - To unsubscribe from this list: send the line "unsubscribe linux-ia64" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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