From d099b9a70e5382c5bbf131d71c0383cca0bc8d73 Mon Sep 17 00:00:00 2001 From: Thinh Nguyen Date: Mon, 29 Nov 2021 18:53:22 -0800 Subject: [PATCH] UPSTREAM: usb: dwc3: gadget: Skip reading GEVNTSIZn The driver knows what it needs to set for GEVNTSIZn, and the controller doesn't modify this register unless there's a hard reset. To save a few microseconds of register read in read-modify-write operation, simply do register write with the expected values. This can improve performance when there are many interrupts generated, which the driver needs to check and handle. Signed-off-by: Thinh Nguyen Link: https://lore.kernel.org/r/efddf4ee5821c4bc5ae7ad90d629ec7a0ebcbf9a.1638240306.git.Thinh.Nguyen@synopsys.com Signed-off-by: Greg Kroah-Hartman (cherry picked from commit 76c4c95dac0da03f64d8b59a8834faf8020af8dc) Bug: 263189538 Change-Id: I7dec7b568f12b1529ab1e52a600056be98910f02 Signed-off-by: Krishna Kurapati --- drivers/usb/dwc3/gadget.c | 12 ++++-------- 1 file changed, 4 insertions(+), 8 deletions(-) diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c index b3e096744d48..4de2f1d3d35f 100644 --- a/drivers/usb/dwc3/gadget.c +++ b/drivers/usb/dwc3/gadget.c @@ -4201,7 +4201,6 @@ static irqreturn_t dwc3_process_event_buf(struct dwc3_event_buffer *evt) struct dwc3 *dwc = evt->dwc; irqreturn_t ret = IRQ_NONE; int left; - u32 reg; left = evt->count; @@ -4232,9 +4231,8 @@ static irqreturn_t dwc3_process_event_buf(struct dwc3_event_buffer *evt) ret = IRQ_HANDLED; /* Unmask interrupt */ - reg = dwc3_readl(dwc->regs, DWC3_GEVNTSIZ(0)); - reg &= ~DWC3_GEVNTSIZ_INTMASK; - dwc3_writel(dwc->regs, DWC3_GEVNTSIZ(0), reg); + dwc3_writel(dwc->regs, DWC3_GEVNTSIZ(0), + DWC3_GEVNTSIZ_SIZE(evt->length)); if (dwc->imod_interval) { dwc3_writel(dwc->regs, DWC3_GEVNTCOUNT(0), DWC3_GEVNTCOUNT_EHB); @@ -4268,7 +4266,6 @@ static irqreturn_t dwc3_check_event_buf(struct dwc3_event_buffer *evt) struct dwc3 *dwc = evt->dwc; u32 amount; u32 count; - u32 reg; if (pm_runtime_suspended(dwc->dev)) { pm_runtime_get(dwc->dev); @@ -4295,9 +4292,8 @@ static irqreturn_t dwc3_check_event_buf(struct dwc3_event_buffer *evt) evt->flags |= DWC3_EVENT_PENDING; /* Mask interrupt */ - reg = dwc3_readl(dwc->regs, DWC3_GEVNTSIZ(0)); - reg |= DWC3_GEVNTSIZ_INTMASK; - dwc3_writel(dwc->regs, DWC3_GEVNTSIZ(0), reg); + dwc3_writel(dwc->regs, DWC3_GEVNTSIZ(0), + DWC3_GEVNTSIZ_INTMASK | DWC3_GEVNTSIZ_SIZE(evt->length)); amount = min(count, evt->length - evt->lpos); memcpy(evt->cache + evt->lpos, evt->buf + evt->lpos, amount);