From: Stephen M. Cameron Date: Thu, 6 Jan 2011 20:48:29 +0000 (-0600) Subject: [SCSI] hpsa: allow driver to put controller in either simple or performant mode X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=02ec19c82e87e3748d326ca5e15e7ddb18c73476;p=linux-beck.git [SCSI] hpsa: allow driver to put controller in either simple or performant mode Signed-off-by: Stephen M. Cameron Signed-off-by: James Bottomley --- diff --git a/Documentation/scsi/hpsa.txt b/Documentation/scsi/hpsa.txt index dca658362cbf..b14e6ee00a95 100644 --- a/Documentation/scsi/hpsa.txt +++ b/Documentation/scsi/hpsa.txt @@ -28,6 +28,12 @@ boot parameter "hpsa_allow_any=1" is specified, however these are not tested nor supported by HP with this driver. For older Smart Arrays, the cciss driver should still be used. +The "hpsa_simple_mode=1" boot parameter may be used to prevent the driver from +putting the controller into "performant" mode. The difference is that with simple +mode, each command completion requires an interrupt, while with "performant mode" +(the default, and ordinarily better performing) it is possible to have multiple +command completions indicated by a single interrupt. + HPSA specific entries in /sys ----------------------------- diff --git a/drivers/scsi/hpsa.c b/drivers/scsi/hpsa.c index 4fb62c2aac05..10076f1868e0 100644 --- a/drivers/scsi/hpsa.c +++ b/drivers/scsi/hpsa.c @@ -74,6 +74,10 @@ static int hpsa_allow_any; module_param(hpsa_allow_any, int, S_IRUGO|S_IWUSR); MODULE_PARM_DESC(hpsa_allow_any, "Allow hpsa driver to access unknown HP Smart Array hardware"); +static int hpsa_simple_mode; +module_param(hpsa_simple_mode, int, S_IRUGO|S_IWUSR); +MODULE_PARM_DESC(hpsa_simple_mode, + "Use 'simple mode' rather than 'performant mode'"); /* define the PCI info for the cards we can control */ static const struct pci_device_id hpsa_pci_device_id[] = { @@ -4038,6 +4042,9 @@ static __devinit void hpsa_put_ctlr_into_performant_mode(struct ctlr_info *h) { u32 trans_support; + if (hpsa_simple_mode) + return; + trans_support = readl(&(h->cfgtable->TransportSupport)); if (!(trans_support & PERFORMANT_MODE)) return;