UPSTREAM: usb: dwc3: gadget: disable automatic calculation of ACK TP NUMP

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.

Change-Id: Icf53af4cd1fc7a9fed1731dbef3ba3abbaa68783
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Wu Liang feng <wulf@rock-chips.com>
(cherry picked from commit 2a58f9c12bb360f38fb39e470bb5ff94014356e6)

diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
index 65df6d2dc5801c1cfa9724bfe0476afc1a3b03de..78f29796f45321191b0636717628f46f2e6388a3 100644 (file)
--- a/drivers/usb/dwc3/core.h
+++ b/drivers/usb/dwc3/core.h
@@ -166,6 +166,11 @@
 #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 0d3873f7b657a7cc8eea54f777c79c91a0c554e9..495aa13d85e26dc52a774a0d7b1584109f032cb5 100644 (file)
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -1673,6 +1673,17 @@ 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);