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usb: dwc3: gadget: Skip reading GEVNTSIZn

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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 <Thinh.Nguyen@synopsys.com>
Link: https://lore.kernel.org/r/efddf4ee5821c4bc5ae7ad90d629ec7a0ebcbf9a.1638240306.git.Thinh.Nguyen@synopsys.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Thinh Nguyen 2021-11-29 18:53:22 -08:00 committed by Greg Kroah-Hartman
parent a02a26eb0a
commit 76c4c95dac
1 changed files with 4 additions and 8 deletions
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12
drivers/usb/dwc3/gadget.c
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@ -4082,7 +4082,6 @@ 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;
@ -4114,9 +4113,8 @@ 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);
@ -4145,7 +4143,6 @@ 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);
@ -4172,9 +4169,8 @@ 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);