diff options
| author | Tejun Heo <htejun@gmail.com> | 2008-03-10 10:25:25 +0900 |
|---|---|---|
| committer | Jeff Garzik <jeff@garzik.org> | 2008-03-17 08:26:50 -0400 |
| commit | a22e64443f0aa4aa4e3c56a49e5c060e90752c07 (patch) | |
| tree | cc9db844ba0099aced1ad1faf3859da84ab75a09 /drivers/ata | |
| parent | dea55137634226fd74d5187a15dee1244ec252cb (diff) | |
ahci: implement skip_host_reset parameter
Under certain circumstances (SSP turned off by the BIOS) and for
debugging purposes, skipping global controller reset is helpful. Add
a kernel parameter for it.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Diffstat (limited to 'drivers/ata')
| -rw-r--r-- | drivers/ata/ahci.c | 48 |
1 files changed, 29 insertions, 19 deletions
diff --git a/drivers/ata/ahci.c b/drivers/ata/ahci.c index 53f5afd9420..bbfccdbba3a 100644 --- a/drivers/ata/ahci.c +++ b/drivers/ata/ahci.c @@ -49,6 +49,10 @@ #define DRV_NAME "ahci" #define DRV_VERSION "3.0" +static int ahci_skip_host_reset; +module_param_named(skip_host_reset, ahci_skip_host_reset, int, 0444); +MODULE_PARM_DESC(skip_host_reset, "skip global host reset (0=don't skip, 1=skip)"); + static int ahci_enable_alpm(struct ata_port *ap, enum link_pm policy); static void ahci_disable_alpm(struct ata_port *ap); @@ -1088,29 +1092,35 @@ static int ahci_reset_controller(struct ata_host *host) ahci_enable_ahci(mmio); /* global controller reset */ - tmp = readl(mmio + HOST_CTL); - if ((tmp & HOST_RESET) == 0) { - writel(tmp | HOST_RESET, mmio + HOST_CTL); - readl(mmio + HOST_CTL); /* flush */ - } + if (!ahci_skip_host_reset) { + tmp = readl(mmio + HOST_CTL); + if ((tmp & HOST_RESET) == 0) { + writel(tmp | HOST_RESET, mmio + HOST_CTL); + readl(mmio + HOST_CTL); /* flush */ + } - /* reset must complete within 1 second, or - * the hardware should be considered fried. - */ - ssleep(1); + /* reset must complete within 1 second, or + * the hardware should be considered fried. + */ + ssleep(1); - tmp = readl(mmio + HOST_CTL); - if (tmp & HOST_RESET) { - dev_printk(KERN_ERR, host->dev, - "controller reset failed (0x%x)\n", tmp); - return -EIO; - } + tmp = readl(mmio + HOST_CTL); + if (tmp & HOST_RESET) { + dev_printk(KERN_ERR, host->dev, + "controller reset failed (0x%x)\n", tmp); + return -EIO; + } - /* turn on AHCI mode */ - ahci_enable_ahci(mmio); + /* turn on AHCI mode */ + ahci_enable_ahci(mmio); - /* some registers might be cleared on reset. restore initial values */ - ahci_restore_initial_config(host); + /* Some registers might be cleared on reset. Restore + * initial values. + */ + ahci_restore_initial_config(host); + } else + dev_printk(KERN_INFO, host->dev, + "skipping global host reset\n"); if (pdev->vendor == PCI_VENDOR_ID_INTEL) { u16 tmp16; |