Now that we calculate DCFG.NUMP, we can disable dwc3's automatic calculation so we maximize our chances of very high throughtput through the use of bursts. Signed-off-by: Felipe Balbi <felipe.balbi@xxxxxxxxxxxxxxx> --- drivers/usb/dwc3/core.h | 5 +++++ drivers/usb/dwc3/gadget.c | 11 +++++++++++ 2 files changed, 16 insertions(+) diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h index c5f576aa1903..186a8868829f 100644 --- a/drivers/usb/dwc3/core.h +++ b/drivers/usb/dwc3/core.h @@ -165,6 +165,11 @@ #define DWC3_DESCFETCHQ 13 #define DWC3_EVENTQ 15 +/* Global RX Threshold Configuration Register */ +#define DWC3_GRXTHRCFG_MAXRXBURSTSIZE(n) (((n) & 0x1f) << 19) +#define DWC3_GRXTHRCFG_RXPKTCNT(n) (((n) & 0xf) << 24) +#define DWC3_GRXTHRCFG_PKTCNTSEL (1 << 29) + /* Global Configuration Register */ #define DWC3_GCTL_PWRDNSCALE(n) ((n) << 19) #define DWC3_GCTL_U2RSTECN (1 << 16) diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c index 4b681b0d420f..c3b0d01e1960 100644 --- a/drivers/usb/dwc3/gadget.c +++ b/drivers/usb/dwc3/gadget.c @@ -1669,6 +1669,17 @@ static int dwc3_gadget_start(struct usb_gadget *g, } dwc3_writel(dwc->regs, DWC3_DCFG, reg); + /* + * We are telling dwc3 that we want to use DCFG.NUMP as ACK TP's NUMP + * field instead of letting dwc3 itself calculate that automatically. + * + * This way, we maximize the chances that we'll be able to get several + * bursts of data without going through any sort of endpoint throttling. + */ + reg = dwc3_readl(dwc->regs, DWC3_GRXTHRCFG); + reg &= ~DWC3_GRXTHRCFG_PKTCNTSEL; + dwc3_writel(dwc->regs, DWC3_GRXTHRCFG, reg); + /* Start with SuperSpeed Default */ dwc3_gadget_ep0_desc.wMaxPacketSize = cpu_to_le16(512); -- 2.8.1 -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
