From: Bartlomiej Zolnierkiewicz Date: Tue, 2 Dec 2008 19:40:03 +0000 (+0100) Subject: amd74xx: workaround unreliable AltStatus register for nVidia controllers X-Git-Tag: v2.6.28-rc8~75^2~5 X-Git-Url: http://www.pilppa.org/gitweb/gitweb.cgi?a=commitdiff_plain;h=6636487e8dc49a1c43fed336bdc4a2f3d7ce6881;p=linux-2.6-omap-h63xx.git amd74xx: workaround unreliable AltStatus register for nVidia controllers It seems that on some nVidia controllers using AltStatus register can be unreliable so default to Status register if the PCI device is in Compatibility Mode. In order to achieve this: * Add ide_pci_is_in_compatibility_mode() inline helper to . * Add IDE_HFLAG_BROKEN_ALTSTATUS host flag and set it in amd74xx host driver for nVidia controllers in Compatibility Mode. * Teach actual_try_to_identify() and drive_is_ready() about the new flag. This fixes the regression caused by removal of CONFIG_IDEPCI_SHARE_IRQ config option in 2.6.25 and using AltStatus register unconditionally when available (kernel.org bugs #11659 and #10216). [ Moreover for CONFIG_IDEPCI_SHARE_IRQ=y (which is what most people and distributions use) it never worked correctly. ] Thanks to Remy LABENE and Lars Winterfeld for help with debugging the problem. More info at: http://bugzilla.kernel.org/show_bug.cgi?id=11659 http://bugzilla.kernel.org/show_bug.cgi?id=10216 Reported-by: Remy LABENE Tested-by: Remy LABENE Tested-by: Lars Winterfeld Acked-by: Borislav Petkov Signed-off-by: Bartlomiej Zolnierkiewicz --- diff --git a/drivers/ide/amd74xx.c b/drivers/ide/amd74xx.c index 81ec73134ed..c6bcd3014a2 100644 --- a/drivers/ide/amd74xx.c +++ b/drivers/ide/amd74xx.c @@ -3,7 +3,7 @@ * IDE driver for Linux. * * Copyright (c) 2000-2002 Vojtech Pavlik - * Copyright (c) 2007 Bartlomiej Zolnierkiewicz + * Copyright (c) 2007-2008 Bartlomiej Zolnierkiewicz * * Based on the work of: * Andre Hedrick @@ -263,6 +263,15 @@ static int __devinit amd74xx_probe(struct pci_dev *dev, const struct pci_device_ d.udma_mask = ATA_UDMA5; } + /* + * It seems that on some nVidia controllers using AltStatus + * register can be unreliable so default to Status register + * if the device is in Compatibility Mode. + */ + if (dev->vendor == PCI_VENDOR_ID_NVIDIA && + ide_pci_is_in_compatibility_mode(dev)) + d.host_flags |= IDE_HFLAG_BROKEN_ALTSTATUS; + printk(KERN_INFO "%s %s: UDMA%s controller\n", d.name, pci_name(dev), amd_dma[fls(d.udma_mask) - 1]); diff --git a/drivers/ide/ide-iops.c b/drivers/ide/ide-iops.c index 5d6ba14e211..142b9573d64 100644 --- a/drivers/ide/ide-iops.c +++ b/drivers/ide/ide-iops.c @@ -468,7 +468,8 @@ int drive_is_ready (ide_drive_t *drive) * an interrupt with another pci card/device. We make no assumptions * about possible isa-pnp and pci-pnp issues yet. */ - if (hwif->io_ports.ctl_addr) + if (hwif->io_ports.ctl_addr && + (hwif->host_flags & IDE_HFLAG_BROKEN_ALTSTATUS) == 0) stat = hwif->tp_ops->read_altstatus(hwif); else /* Note: this may clear a pending IRQ!! */ diff --git a/drivers/ide/ide-probe.c b/drivers/ide/ide-probe.c index 1649ea54f76..c55bdbd2231 100644 --- a/drivers/ide/ide-probe.c +++ b/drivers/ide/ide-probe.c @@ -266,7 +266,8 @@ static int actual_try_to_identify (ide_drive_t *drive, u8 cmd) /* take a deep breath */ msleep(50); - if (io_ports->ctl_addr) { + if (io_ports->ctl_addr && + (hwif->host_flags & IDE_HFLAG_BROKEN_ALTSTATUS) == 0) { a = tp_ops->read_altstatus(hwif); s = tp_ops->read_status(hwif); if ((a ^ s) & ~ATA_IDX) diff --git a/include/linux/ide.h b/include/linux/ide.h index 54525be4b5f..010fb26a157 100644 --- a/include/linux/ide.h +++ b/include/linux/ide.h @@ -1296,6 +1296,13 @@ extern int __ide_pci_register_driver(struct pci_driver *driver, struct module *o #define ide_pci_register_driver(d) pci_register_driver(d) #endif +static inline int ide_pci_is_in_compatibility_mode(struct pci_dev *dev) +{ + if ((dev->class >> 8) == PCI_CLASS_STORAGE_IDE && (dev->class & 5) != 5) + return 1; + return 0; +} + void ide_pci_setup_ports(struct pci_dev *, const struct ide_port_info *, int, hw_regs_t *, hw_regs_t **); void ide_setup_pci_noise(struct pci_dev *, const struct ide_port_info *); @@ -1375,6 +1382,7 @@ enum { IDE_HFLAG_IO_32BIT = (1 << 24), /* unmask IRQs */ IDE_HFLAG_UNMASK_IRQS = (1 << 25), + IDE_HFLAG_BROKEN_ALTSTATUS = (1 << 26), /* serialize ports if DMA is possible (for sl82c105) */ IDE_HFLAG_SERIALIZE_DMA = (1 << 27), /* force host out of "simplex" mode */