[coreboot-gerrit] New patch to review for coreboot: 25853b9 libpayload dwc2: Use a new FIFO allocation method

[Patrick Georgi]

Patrick Georgi ([e-mail]) just uploaded a new patch set to gerrit, which you can find at http://review.coreboot.org/9454

-gerrit

commit 25853b969f1180e532007af6007d4e308ad64213
Author: huang lin 
Date:   Thu Dec 4 18:25:47 2014 +0800

libpayload dwc2: Use a new FIFO allocation method

Total FIFO length is split into 512 byte blocks,
    because the max packet size in coreboot is 512 byte.
    Allocate these blocks to GRXFSIZ and GNPTXFSZ evenly.
    This method avoids hardcoding and make the FIFO size value
    work for dwc2 controllers that have a different FIFO ram size.

BUG=chrome-os-partner:32634
    BRANCH=None
    TEST=Boot kernel from USB

Change-Id: I78ce0fa4c4600fb56c991874a93bdd6674e648c2
    Signed-off-by: Patrick Georgi 
    Original-Commit-Id: 5645a25e95f84359cd10fc9fcf56e1f73fd6ce87
    Original-Change-Id: Ib50a08c193f7f65392810ca3528a97554f2c3999
    Original-Signed-off-by: huang lin 
    Original-Reviewed-on: https://chromium-review.googlesource.com/233119
    Original-Reviewed-by: Julius Werner 
---
 payloads/libpayload/drivers/usb/dwc2.c         | 23 +++++++++++++++++++----
 payloads/libpayload/drivers/usb/dwc2_private.h | 16 ++++++++++++++--
 2 files changed, 33 insertions(+), 6 deletions(-)

diff --git a/payloads/libpayload/drivers/usb/dwc2.c b/payloads/libpayload/drivers/usb/dwc2.c
index 7af7718..0830c9e 100644
--- a/payloads/libpayload/drivers/usb/dwc2.c
+++ b/payloads/libpayload/drivers/usb/dwc2.c
@@ -35,11 +35,12 @@ static void dwc2_reinit(hci_t *controller)
    gintsts_t gintsts = { .d32 = 0 };
    gahbcfg_t gahbcfg = { .d32 = 0 };
    grxfsiz_t grxfsiz = { .d32 = 0 };
+	ghwcfg3_t hwcfg3 = { .d32 = 0 };
    hcintmsk_t hcintmsk = { .d32 = 0 };
    gnptxfsiz_t gnptxfsiz = { .d32 = 0 };

const int timeout = 10000;
-	int i;
+	int i, fifo_blocks, tx_blocks;

/* Wait for AHB idle */
    for (i = 0; i < timeout; i++) {
@@ -86,10 +87,24 @@ static void dwc2_reinit(hci_t *controller)
     * The non-periodic tx fifo and rx fifo share one continuous
     * piece of IP-internal SRAM.
     */
-	grxfsiz.rxfdep = DWC2_RXFIFO_DEPTH;
+
+	/*
+	 * Read total data FIFO depth from HWCFG3
+	 * this value is in terms of 32-bit words
+	 */
+	hwcfg3.d32 = readl(&reg->core.ghwcfg3);
+	/*
+	 * Reserve 2 spaces for the status entries of receive packets
+	 * and 2 spaces for bulk an control OUT endpoints. Calculate how
+	 * many blocks can be alloted, assume largest packet size is 512.
+	 */
+	fifo_blocks = (hwcfg3.dfifodepth - 4) / (512 / 4);
+	tx_blocks = fifo_blocks / 2;
+
+	grxfsiz.rxfdep = (fifo_blocks - tx_blocks) * (512 / 4) + 4;
    writel(grxfsiz.d32, &reg->core.grxfsiz);
-	gnptxfsiz.nptxfstaddr = DWC2_RXFIFO_DEPTH;
-	gnptxfsiz.nptxfdep = DWC2_NPTXFIFO_DEPTH;
+	gnptxfsiz.nptxfstaddr = grxfsiz.rxfdep;
+	gnptxfsiz.nptxfdep = tx_blocks * (512 / 4);
    writel(gnptxfsiz.d32, &reg->core.gnptxfsiz);

/* Init host channels */
diff --git a/payloads/libpayload/drivers/usb/dwc2_private.h b/payloads/libpayload/drivers/usb/dwc2_private.h
index 9bd8376..fc658bf 100644
--- a/payloads/libpayload/drivers/usb/dwc2_private.h
+++ b/payloads/libpayload/drivers/usb/dwc2_private.h
@@ -374,7 +374,6 @@ typedef union {
    struct {
    	unsigned nptxfstaddr:16;
    	unsigned nptxfdep:16;
-#define DWC2_NPTXFIFO_DEPTH 0x80
    };
 } gnptxfsiz_t;

@@ -390,7 +389,6 @@ typedef union {
     */
    struct {
    	unsigned rxfdep:16;
-#define DWC2_RXFIFO_DEPTH 0x200
    	unsigned reserved:16;
    };
 } grxfsiz_t;
@@ -438,6 +436,20 @@ typedef union {
 } gintsts_t;

/**
+ * This union represents the bit fields of the User HW Config3 Register
+ * (GHWCFG3).
+ */
+typedef union {
+	/* raw register data */
+	uint32_t d32;
+	/* register bits */
+	struct {
+		unsigned reserved:16;
+		unsigned dfifodepth:16;
+	};
+} ghwcfg3_t;
+
+/**
  * This union represents the bit fields in the Host Configuration Register.
  */
 typedef union {