[PATCH 2/3] usb: dwc3: add dwc3_readl_notrace() function

[Linyu Yuan <quic_linyyuan@xxxxxxxxxxx>]

There are multiple places which will retry up to 10000 times to read a
register, when trace event enable, it is not good as all events may show
same data.

Add dwc3_readl_notrace() function which will not save trace event
when read register.

Signed-off-by: Linyu Yuan <quic_linyyuan@xxxxxxxxxxx>
---
 drivers/usb/dwc3/core.c   |  2 +-
 drivers/usb/dwc3/gadget.c | 12 ++++++------
 drivers/usb/dwc3/io.h     | 10 ++++++++++
 drivers/usb/dwc3/ulpi.c   |  2 +-
 4 files changed, 18 insertions(+), 8 deletions(-)

diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
index 476b636..550bb23 100644
--- a/drivers/usb/dwc3/core.c
+++ b/drivers/usb/dwc3/core.c
@@ -297,7 +297,7 @@ int dwc3_core_soft_reset(struct dwc3 *dwc)
 		retries = 10;
 
 	do {
-		reg = dwc3_readl(dwc->regs, DWC3_DCTL);
+		reg = dwc3_readl_notrace(dwc->regs, DWC3_DCTL);
 		if (!(reg & DWC3_DCTL_CSFTRST))
 			goto done;
 
diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index 7899765..f2126f24 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -97,7 +97,7 @@ int dwc3_gadget_set_link_state(struct dwc3 *dwc, enum dwc3_link_state state)
 	 */
 	if (!DWC3_VER_IS_PRIOR(DWC3, 194A)) {
 		while (--retries) {
-			reg = dwc3_readl(dwc->regs, DWC3_DSTS);
+			reg = dwc3_readl_notrace(dwc->regs, DWC3_DSTS);
 			if (reg & DWC3_DSTS_DCNRD)
 				udelay(5);
 			else
@@ -128,7 +128,7 @@ int dwc3_gadget_set_link_state(struct dwc3 *dwc, enum dwc3_link_state state)
 	/* wait for a change in DSTS */
 	retries = 10000;
 	while (--retries) {
-		reg = dwc3_readl(dwc->regs, DWC3_DSTS);
+		reg = dwc3_readl_notrace(dwc->regs, DWC3_DSTS);
 
 		if (DWC3_DSTS_USBLNKST(reg) == state)
 			return 0;
@@ -239,7 +239,7 @@ int dwc3_send_gadget_generic_command(struct dwc3 *dwc, unsigned int cmd,
 	dwc3_writel(dwc->regs, DWC3_DGCMD, cmd | DWC3_DGCMD_CMDACT);
 
 	do {
-		reg = dwc3_readl(dwc->regs, DWC3_DGCMD);
+		reg = dwc3_readl_notrace(dwc->regs, DWC3_DGCMD);
 		if (!(reg & DWC3_DGCMD_CMDACT)) {
 			status = DWC3_DGCMD_STATUS(reg);
 			if (status)
@@ -375,7 +375,7 @@ int dwc3_send_gadget_ep_cmd(struct dwc3_ep *dep, unsigned int cmd,
 	}
 
 	do {
-		reg = dwc3_readl(dep->regs, DWC3_DEPCMD);
+		reg = dwc3_readl_notrace(dep->regs, DWC3_DEPCMD);
 		if (!(reg & DWC3_DEPCMD_CMDACT)) {
 			cmd_status = DWC3_DEPCMD_STATUS(reg);
 
@@ -2324,7 +2324,7 @@ static int __dwc3_gadget_wakeup(struct dwc3 *dwc)
 	retries = 20000;
 
 	while (retries--) {
-		reg = dwc3_readl(dwc->regs, DWC3_DSTS);
+		reg = dwc3_readl_notrace(dwc->regs, DWC3_DSTS);
 
 		/* in HS, means ON */
 		if (DWC3_DSTS_USBLNKST(reg) == DWC3_LINK_STATE_U0)
@@ -2510,7 +2510,7 @@ static int dwc3_gadget_run_stop(struct dwc3 *dwc, int is_on, int suspend)
 
 	do {
 		usleep_range(1000, 2000);
-		reg = dwc3_readl(dwc->regs, DWC3_DSTS);
+		reg = dwc3_readl_notrace(dwc->regs, DWC3_DSTS);
 		reg &= DWC3_DSTS_DEVCTRLHLT;
 	} while (--timeout && !(!is_on ^ !reg));
 
diff --git a/drivers/usb/dwc3/io.h b/drivers/usb/dwc3/io.h
index d9283f4..d24513e 100644
--- a/drivers/usb/dwc3/io.h
+++ b/drivers/usb/dwc3/io.h
@@ -37,6 +37,16 @@ static inline u32 dwc3_readl(void __iomem *base, u32 offset)
 	return value;
 }
 
+static inline u32 dwc3_readl_notrace(void __iomem *base, u32 offset)
+{
+	/*
+	 * We requested the mem region starting from the Globals address
+	 * space, see dwc3_probe in core.c.
+	 * The offsets are also given starting from Globals address space.
+	 */
+	return readl(base + offset);
+}
+
 static inline void dwc3_writel(void __iomem *base, u32 offset, u32 value)
 {
 	/*
diff --git a/drivers/usb/dwc3/ulpi.c b/drivers/usb/dwc3/ulpi.c
index f23f4c9..7b220b0 100644
--- a/drivers/usb/dwc3/ulpi.c
+++ b/drivers/usb/dwc3/ulpi.c
@@ -39,7 +39,7 @@ static int dwc3_ulpi_busyloop(struct dwc3 *dwc, u8 addr, bool read)
 
 	while (count--) {
 		ndelay(ns);
-		reg = dwc3_readl(dwc->regs, DWC3_GUSB2PHYACC(0));
+		reg = dwc3_readl_notrace(dwc->regs, DWC3_GUSB2PHYACC(0));
 		if (reg & DWC3_GUSB2PHYACC_DONE)
 			return 0;
 		cpu_relax();
-- 
2.7.4