From 51e9f2ff83df6b1c81c5c44f4486c68ed87aa20e Mon Sep 17 00:00:00 2001 From: Jeff Garzik Date: Fri, 27 Jan 2006 16:50:27 -0500 Subject: [libata sata_sil] implement 'slow_down' module parameter On occasion, a user will submit a patch that enables the "mod15write" quirk for their device. Enabling this quirk has the effect of clamping all ATA commands to no more than 15 sectors. The intended use of this quirk is to stop the controller from generating FIS's of unusual size ("but Wesley, what about the FOUS's?"), which in turn works around problems in a of hard drives. One side effect of this quirk is greatly decreased performance. Users often enable the mod15write quirk to fix various system, power, chip, and/or driver problems. For a few rare problematic cases, enabling this has cured lockups or data corruption. Rather than add bogus listings to the mod15write quirk list (I get a patch every month doing such), we add a 'slow_down' module parameter. This allows users to employ a performance sledgehammer in the hopes of curing a problem. It defaults to off (0), of course. --- drivers/scsi/sata_sil.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/drivers/scsi/sata_sil.c b/drivers/scsi/sata_sil.c index b017f85e6d6..17f74d3c10e 100644 --- a/drivers/scsi/sata_sil.c +++ b/drivers/scsi/sata_sil.c @@ -231,6 +231,10 @@ MODULE_LICENSE("GPL"); MODULE_DEVICE_TABLE(pci, sil_pci_tbl); MODULE_VERSION(DRV_VERSION); +static int slow_down = 0; +module_param(slow_down, int, 0444); +MODULE_PARM_DESC(slow_down, "Sledgehammer used to work around random problems, by limiting commands to 15 sectors (0=off, 1=on)"); + static unsigned char sil_get_device_cache_line(struct pci_dev *pdev) { @@ -354,8 +358,10 @@ static void sil_dev_config(struct ata_port *ap, struct ata_device *dev) } /* limit requests to 15 sectors */ - if ((ap->flags & SIL_FLAG_MOD15WRITE) && (quirks & SIL_QUIRK_MOD15WRITE)) { - printk(KERN_INFO "ata%u(%u): applying Seagate errata fix\n", + if (slow_down || + ((ap->flags & SIL_FLAG_MOD15WRITE) && + (quirks & SIL_QUIRK_MOD15WRITE))) { + printk(KERN_INFO "ata%u(%u): applying Seagate errata fix (mod15write workaround)\n", ap->id, dev->devno); ap->host->max_sectors = 15; ap->host->hostt->max_sectors = 15; -- cgit v1.2.3-18-g5258 From ddef9bb367b19383df627e388cb4c01c86ddba6c Mon Sep 17 00:00:00 2001 From: Jeff Garzik Date: Thu, 2 Feb 2006 16:17:06 -0500 Subject: [libata sata_mv] do not enable PCI MSI by default Several bug reports have come in, noting that disabling CONFIG_PCI_MSI has fixed their problems with this driver. This may be generic system issues, but there is also the probability of unimplemented hardware errata workarounds. Until this ream of bug reports is sorted out, we can get them going in non-MSI interrupt mode. As such, this change adds an 'msi' module option, which defaults to off. --- drivers/scsi/sata_mv.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) diff --git a/drivers/scsi/sata_mv.c b/drivers/scsi/sata_mv.c index cd54244058b..6fddf17a3b7 100644 --- a/drivers/scsi/sata_mv.c +++ b/drivers/scsi/sata_mv.c @@ -509,6 +509,12 @@ static const struct mv_hw_ops mv6xxx_ops = { .reset_bus = mv_reset_pci_bus, }; +/* + * module options + */ +static int msi; /* Use PCI msi; either zero (off, default) or non-zero */ + + /* * Functions */ @@ -2191,7 +2197,7 @@ static int mv_init_one(struct pci_dev *pdev, const struct pci_device_id *ent) } /* Enable interrupts */ - if (pci_enable_msi(pdev) == 0) { + if (msi && pci_enable_msi(pdev) == 0) { hpriv->hp_flags |= MV_HP_FLAG_MSI; } else { pci_intx(pdev, 1); @@ -2246,5 +2252,8 @@ MODULE_LICENSE("GPL"); MODULE_DEVICE_TABLE(pci, mv_pci_tbl); MODULE_VERSION(DRV_VERSION); +module_param(msi, int, 0444); +MODULE_PARM_DESC(msi, "Enable use of PCI MSI (0=off, 1=on)"); + module_init(mv_init); module_exit(mv_exit); -- cgit v1.2.3-18-g5258