From a4d88302268d1e458f7c6eb7855f1ba4b3a7cffc Mon Sep 17 00:00:00 2001 From: Sarah Sharp <sarah.a.sharp@linux.intel.com> Date: Thu, 14 May 2009 11:44:26 -0700 Subject: [PATCH] USB: xHCI: Fix interrupt moderation. Mask off the lower 16 bits of the interrupt control register, instead of masking off the upper 16 bits. The interrupt moderation interval field is the lower 16 bytes, and is set to 0x4000 (1ms) by default. The previous code was adding 40 us to the default value, instead of setting it to 40 us. This makes performance really bad. Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> --- drivers/usb/host/xhci-hcd.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/usb/host/xhci-hcd.c b/drivers/usb/host/xhci-hcd.c index 59ee61d2a1980..489657c853e7f 100644 --- a/drivers/usb/host/xhci-hcd.c +++ b/drivers/usb/host/xhci-hcd.c @@ -384,7 +384,7 @@ int xhci_run(struct usb_hcd *hcd) xhci_dbg(xhci, "// Set the interrupt modulation register\n"); temp = xhci_readl(xhci, &xhci->ir_set->irq_control); - temp &= 0xffff; + temp &= ~ER_IRQ_INTERVAL_MASK; temp |= (u32) 160; xhci_writel(xhci, temp, &xhci->ir_set->irq_control); -- GitLab