sata_sil24: configure max read request size to 4k

Due to request posting limitations, bandwidth of sil3132 is limited to
around 120MB/s with the minimum pci-e payload size (128bytes) which is
used by most consumer systems.  However, write throughput can be
slightly (~3%) increased by increasing the max read requeset size.
Configure it to 4k which is the maximum supported.  This optimization
is also done by SIMG's windows driver.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
This commit is contained in:
Tejun Heo 2008-10-25 14:26:54 +09:00 committed by Jeff Garzik
parent 3cd8ddbd86
commit e8b3b5e9f5

View File

@ -1329,6 +1329,11 @@ static int sil24_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
} }
} }
/* Set max read request size to 4096. This slightly increases
* write throughput for pci-e variants.
*/
pcie_set_readrq(pdev, 4096);
sil24_init_controller(host); sil24_init_controller(host);
pci_set_master(pdev); pci_set_master(pdev);