ahci: add a module parameter to ignore the SSS flags for async scanning
The SSS flag, which directs the OS to spin up one disk at a time
to not have the PSU blow out, sometimes gets set even when not needed.
The effect of this is a longer-than-needed boot time.
This patch adds a module parameter that makes the driver ignore SSS
at least as far as the parallel scan during boot is concerned...
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
diff --git a/drivers/ata/ahci.c b/drivers/ata/ahci.c
index 77bba4c..a603bbf 100644
--- a/drivers/ata/ahci.c
+++ b/drivers/ata/ahci.c
@@ -61,9 +61,14 @@
#define EM_MSG_LED_VALUE_ON 0x00010000
static int ahci_skip_host_reset;
+static int ahci_ignore_sss;
+
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)");
+module_param_named(ignore_sss, ahci_ignore_sss, int, 0444);
+MODULE_PARM_DESC(ignore_sss, "Ignore staggered spinup flag (0=don't ignore, 1=ignore)");
+
static int ahci_enable_alpm(struct ata_port *ap,
enum link_pm policy);
static void ahci_disable_alpm(struct ata_port *ap);
@@ -2692,8 +2697,10 @@
host->iomap = pcim_iomap_table(pdev);
host->private_data = hpriv;
- if (!(hpriv->cap & HOST_CAP_SSS))
+ if (!(hpriv->cap & HOST_CAP_SSS) || ahci_ignore_sss)
host->flags |= ATA_HOST_PARALLEL_SCAN;
+ else
+ printk(KERN_INFO "ahci: SSS flag set, parallel bus scan disabled\n");
if (pi.flags & ATA_FLAG_EM)
ahci_reset_em(host);