[PATCH 0/4] usb: dwc2: gadget: Fix dynamic FIFO initialization flow

[PATCH 0/4] usb: dwc2: gadget: Fix dynamic FIFO initialization flow

[Sevak Arakelyan]

This series fixes FIFO initialization issue of getting wrong insufficent FIFO memory warning.
Fixes duplicate FIFO initialization issue, replaces FIFO flushing code with function calls.
Separates initialization of periodic and non-periodic FIFOs.

Tested on HAPS platform with DWC_hsotg IP version 3.30a.

Sevak Arakelyan (4):
  usb: dwc2: gadget: Fix in TX FIFO initialization flow.
  usb: dwc2: gadget: Remove duplicated FIFO initialization.
  usb: dwc2: gadget: Replace code with function calls.
  usb: dwc2: gadget: Separate non-periodic and periodic FIFO inits

 drivers/usb/dwc2/gadget.c | 96 +++++++++++++++++++----------------------------
 1 file changed, 38 insertions(+), 58 deletions(-)

-- 
2.11.0

[PATCH 1/4] usb: dwc2: gadget: Fix in TX FIFO initialization flow.

[Sevak Arakelyan]

We need to update DPTXFSIZN even if the depth of
current TX FIFO is set to 0.
Loop only for needed TX FIFO count times. This will fix the issue with
wrong insufficient fifo memory WARN_ON.

Signed-off-by: Sevak Arakelyan <sevaka@synopsys.com>
---
 drivers/usb/dwc2/gadget.c | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/drivers/usb/dwc2/gadget.c b/drivers/usb/dwc2/gadget.c
index bc3b3fda5000..0b2d9bf43283 100644
--- a/drivers/usb/dwc2/gadget.c
+++ b/drivers/usb/dwc2/gadget.c
@@ -293,9 +293,13 @@ static void dwc2_hsotg_init_fifo(struct dwc2_hsotg *hsotg)
 	unsigned int ep;
 	unsigned int addr;
 	int timeout;
+	int fifo_count;
 	u32 val;
 	u32 *txfsz = hsotg->params.g_tx_fifo_size;
 
+	if (!hsotg->params.enable_dynamic_fifo)
+		return;
+
 	/* Reset fifo map if not correctly cleared during previous session */
 	WARN_ON(hsotg->fifo_map);
 	hsotg->fifo_map = 0;
@@ -321,9 +325,9 @@ static void dwc2_hsotg_init_fifo(struct dwc2_hsotg *hsotg)
 	 * them to endpoints dynamically according to maxpacket size value of
 	 * given endpoint.
 	 */
-	for (ep = 1; ep < MAX_EPS_CHANNELS; ep++) {
-		if (!txfsz[ep])
-			continue;
+	fifo_count = dwc2_hsotg_tx_fifo_count(hsotg);
+
+	for (ep = 1; ep <= fifo_count; ep++) {
 		val = addr;
 		val |= txfsz[ep] << FIFOSIZE_DEPTH_SHIFT;
 		WARN_ONCE(addr + txfsz[ep] > hsotg->fifo_mem,
-- 
2.11.0

[PATCH 2/4] usb: dwc2: gadget: Remove duplicated FIFO initialization.

[Sevak Arakelyan]

dwc2_hsotg_init is called in dwc2_hsotg_core_init_disconnected and
dwc2_hsotg_init functions. It should be in
dwc2_hsotg_core_init_disconnected and don't need to be called for
the second time, so remove the duplicated one from dwc2_hsotg_init.
Also, remove useless debug prints.

Signed-off-by: Sevak Arakelyan <sevaka@synopsys.com>
---
 drivers/usb/dwc2/gadget.c | 8 --------
 1 file changed, 8 deletions(-)

diff --git a/drivers/usb/dwc2/gadget.c b/drivers/usb/dwc2/gadget.c
index 0b2d9bf43283..46f38604c3b2 100644
--- a/drivers/usb/dwc2/gadget.c
+++ b/drivers/usb/dwc2/gadget.c
@@ -4214,14 +4214,6 @@ static void dwc2_hsotg_init(struct dwc2_hsotg *hsotg)
 	/* Be in disconnected state until gadget is registered */
 	__orr32(hsotg->regs + DCTL, DCTL_SFTDISCON);
 
-	/* setup fifos */
-
-	dev_dbg(hsotg->dev, "GRXFSIZ=0x%08x, GNPTXFSIZ=0x%08x\n",
-		dwc2_readl(hsotg->regs + GRXFSIZ),
-		dwc2_readl(hsotg->regs + GNPTXFSIZ));
-
-	dwc2_hsotg_init_fifo(hsotg);
-
 	/* keep other bits untouched (so e.g. forced modes are not lost) */
 	usbcfg = dwc2_readl(hsotg->regs + GUSBCFG);
 	usbcfg &= ~(GUSBCFG_TOUTCAL_MASK | GUSBCFG_PHYIF16 | GUSBCFG_SRPCAP |
-- 
2.11.0

[PATCH 3/4] usb: dwc2: gadget: Replace code with function calls.

[Sevak Arakelyan]

Replace TX and RX FIFO's flushing and waiting code in
dwc2_hsotg_init_fifo with dwc2_flush_tx_fifo
and dwc2_flush_rx_fifo function calls accordingly.

Signed-off-by: Sevak Arakelyan <sevaka@synopsys.com>
---
 drivers/usb/dwc2/gadget.c | 34 ++++++++--------------------------
 1 file changed, 8 insertions(+), 26 deletions(-)

diff --git a/drivers/usb/dwc2/gadget.c b/drivers/usb/dwc2/gadget.c
index 46f38604c3b2..574562a0286d 100644
--- a/drivers/usb/dwc2/gadget.c
+++ b/drivers/usb/dwc2/gadget.c
@@ -292,7 +292,6 @@ static void dwc2_hsotg_init_fifo(struct dwc2_hsotg *hsotg)
 {
 	unsigned int ep;
 	unsigned int addr;
-	int timeout;
 	int fifo_count;
 	u32 val;
 	u32 *txfsz = hsotg->params.g_tx_fifo_size;
@@ -341,33 +340,16 @@ static void dwc2_hsotg_init_fifo(struct dwc2_hsotg *hsotg)
 	dwc2_writel(hsotg->hw_params.total_fifo_size |
 		    addr << GDFIFOCFG_EPINFOBASE_SHIFT,
 		    hsotg->regs + GDFIFOCFG);
+
 	/*
-	 * according to p428 of the design guide, we need to ensure that
-	 * all fifos are flushed before continuing
+	 * Chapter 2.1.1 of the Programming Guide - The TxFIFOs and the RxFIFO
+	 * must be flushed after the RAM allocation is done, for proper FIFO
+	 * functioning.
+	 *
+	 * 0x10 - all TX FIFOs
 	 */
-
-	dwc2_writel(GRSTCTL_TXFNUM(0x10) | GRSTCTL_TXFFLSH |
-	       GRSTCTL_RXFFLSH, hsotg->regs + GRSTCTL);
-
-	/* wait until the fifos are both flushed */
-	timeout = 100;
-	while (1) {
-		val = dwc2_readl(hsotg->regs + GRSTCTL);
-
-		if ((val & (GRSTCTL_TXFFLSH | GRSTCTL_RXFFLSH)) == 0)
-			break;
-
-		if (--timeout == 0) {
-			dev_err(hsotg->dev,
-				"%s: timeout flushing fifos (GRSTCTL=%08x)\n",
-				__func__, val);
-			break;
-		}
-
-		udelay(1);
-	}
-
-	dev_dbg(hsotg->dev, "FIFOs reset, timeout at %d\n", timeout);
+	dwc2_flush_tx_fifo(hsotg, 0x10);
+	dwc2_flush_rx_fifo(hsotg);
 }
 
 /**
-- 
2.11.0

[PATCH 4/4] usb: dwc2: gadget: Separate non-periodic and periodic FIFO inits

[Sevak Arakelyan]

Separate dwc2_hsotg_init_fifo function into 2 different functions,
for periodic and non-periodic FIFOs. Initialization of non-periodic
FIFOs must be done after soft or USB resets, while initialization
of periodic FIFOs must be done only after soft reset.

Signed-off-by: Sevak Arakelyan <sevaka@synopsys.com>
---
 drivers/usb/dwc2/gadget.c | 46 ++++++++++++++++++++++++----------------------
 1 file changed, 24 insertions(+), 22 deletions(-)

diff --git a/drivers/usb/dwc2/gadget.c b/drivers/usb/dwc2/gadget.c
index 574562a0286d..0bf42a0a3213 100644
--- a/drivers/usb/dwc2/gadget.c
+++ b/drivers/usb/dwc2/gadget.c
@@ -285,10 +285,9 @@ int dwc2_hsotg_tx_fifo_average_depth(struct dwc2_hsotg *hsotg)
 }
 
 /**
- * dwc2_hsotg_init_fifo - initialise non-periodic FIFOs
- * @hsotg: The device instance.
+ * dwc2_hsotg_init_periodic_fifos - initialize periodic FIFOs
  */
-static void dwc2_hsotg_init_fifo(struct dwc2_hsotg *hsotg)
+static void dwc2_hsotg_init_periodic_fifos(struct dwc2_hsotg *hsotg)
 {
 	unsigned int ep;
 	unsigned int addr;
@@ -303,27 +302,12 @@ static void dwc2_hsotg_init_fifo(struct dwc2_hsotg *hsotg)
 	WARN_ON(hsotg->fifo_map);
 	hsotg->fifo_map = 0;
 
-	/* set RX/NPTX FIFO sizes */
-	dwc2_writel(hsotg->params.g_rx_fifo_size, hsotg->regs + GRXFSIZ);
-	dwc2_writel((hsotg->params.g_rx_fifo_size << FIFOSIZE_STARTADDR_SHIFT) |
-		    (hsotg->params.g_np_tx_fifo_size << FIFOSIZE_DEPTH_SHIFT),
-		    hsotg->regs + GNPTXFSIZ);
-
 	/*
-	 * arange all the rest of the TX FIFOs, as some versions of this
-	 * block have overlapping default addresses. This also ensures
-	 * that if the settings have been changed, then they are set to
-	 * known values.
+	 * Arange periodic TX FIFOs to correctly calculated values.
+	 * Start at the end of the GNPTXFSIZ.
 	 */
-
-	/* start at the end of the GNPTXFSIZ, rounded up */
 	addr = hsotg->params.g_rx_fifo_size + hsotg->params.g_np_tx_fifo_size;
 
-	/*
-	 * Configure fifos sizes from provided configuration and assign
-	 * them to endpoints dynamically according to maxpacket size value of
-	 * given endpoint.
-	 */
 	fifo_count = dwc2_hsotg_tx_fifo_count(hsotg);
 
 	for (ep = 1; ep <= fifo_count; ep++) {
@@ -340,6 +324,21 @@ static void dwc2_hsotg_init_fifo(struct dwc2_hsotg *hsotg)
 	dwc2_writel(hsotg->hw_params.total_fifo_size |
 		    addr << GDFIFOCFG_EPINFOBASE_SHIFT,
 		    hsotg->regs + GDFIFOCFG);
+}
+
+/**
+ * dwc2_hsotg_init_non_periodic_fifos - initialize non-periodic FIFOs
+ */
+static void dwc2_hsotg_init_non_periodic_fifos(struct dwc2_hsotg *hsotg)
+{
+	if (!hsotg->params.enable_dynamic_fifo)
+		return;
+
+	/* set RX/NPTX FIFO sizes */
+	dwc2_writel(hsotg->params.g_rx_fifo_size, hsotg->regs + GRXFSIZ);
+	dwc2_writel((hsotg->params.g_rx_fifo_size << FIFOSIZE_STARTADDR_SHIFT) |
+		    (hsotg->params.g_np_tx_fifo_size << FIFOSIZE_DEPTH_SHIFT),
+		    hsotg->regs + GNPTXFSIZ);
 
 	/*
 	 * Chapter 2.1.1 of the Programming Guide - The TxFIFOs and the RxFIFO
@@ -3269,10 +3268,13 @@ void dwc2_hsotg_core_init_disconnected(struct dwc2_hsotg *hsotg,
 	}
 	dwc2_writel(usbcfg, hsotg->regs + GUSBCFG);
 
-	dwc2_hsotg_init_fifo(hsotg);
+	dwc2_hsotg_init_non_periodic_fifos(hsotg);
+
+	if (!is_usb_reset) {
+		dwc2_hsotg_init_periodic_fifos(hsotg);
 
-	if (!is_usb_reset)
 		__orr32(hsotg->regs + DCTL, DCTL_SFTDISCON);
+	}
 
 	dcfg |= DCFG_EPMISCNT(1);
 
-- 
2.11.0