For Gen1 isoc-in transfer, host still send out unexpected ACK after device
finish the burst with a short packet, this will cause an exception on the
connected device, such as, a usb 4k camera.
It can be fixed by setting rxfifo depth less than 3, prefer to use 2 here,
the side-effect is that may cause performance drop about 10%, including
bulk transfer.
Fixes: 926d60ae64a6 ("usb: xhci-mtk: modify the SOF/ITP interval for mt8195")
Signed-off-by: Chunfeng Yun <chunfeng.yun@xxxxxxxxxxxx>
---
drivers/usb/host/xhci-mtk.c | 35 +++++++++++++++++++++++++++++++++--
drivers/usb/host/xhci-mtk.h | 1 +
2 files changed, 34 insertions(+), 2 deletions(-)
diff --git a/drivers/usb/host/xhci-mtk.c b/drivers/usb/host/xhci-mtk.c
index bbdf1b0b7be1..a54535877e90 100644
--- a/drivers/usb/host/xhci-mtk.c
+++ b/drivers/usb/host/xhci-mtk.c
@@ -73,6 +73,9 @@
#define FRMCNT_LEV1_RANG (0x12b << 8)
#define FRMCNT_LEV1_RANG_MASK GENMASK(19, 8)
+#define HSCH_CFG1 0x960
+#define SCH3_RXFIFO_DEPTH_MASK GENMASK(21, 20)
+
#define SS_GEN2_EOF_CFG 0x990
#define SSG2EOF_OFFSET 0x3c
@@ -165,6 +168,33 @@ static void xhci_mtk_set_frame_interval(struct xhci_hcd_mtk *mtk)
writel(value, hcd->regs + SS_GEN2_EOF_CFG);
}
+/*
+ * workaround: usb3.2 gen1 isoc rx hw issue
+ * host send out unexpected ACK afer device fininsh a burst transfer with
+ * a short packet.
+ */
+static void xhci_mtk_rxfifo_depth_set(struct xhci_hcd_mtk *mtk)
+{
+ struct usb_hcd *hcd = mtk->hcd;
+ u32 value;
+
+ if (mtk->rxfifo_depth_quirk) {
+ value = readl(hcd->regs + HSCH_CFG1);
+ value &= ~SCH3_RXFIFO_DEPTH_MASK;
+ value |= FIELD_PREP(SCH3_RXFIFO_DEPTH_MASK, 2);
+ writel(value, hcd->regs + HSCH_CFG1);
+ }
+}
+
+static void xhci_mtk_init_quirk(struct xhci_hcd_mtk *mtk)
+{
+ /* workaround only for mt8195 */
+ xhci_mtk_set_frame_interval(mtk);
+
+ /* workaround for SoCs using SSUSB about before IPM v1.6.0 */
+ xhci_mtk_rxfifo_depth_set(mtk);
+}
+
static int xhci_mtk_host_enable(struct xhci_hcd_mtk *mtk)
{
struct mu3c_ippc_regs __iomem *ippc = mtk->ippc_regs;
@@ -448,8 +478,7 @@ static int xhci_mtk_setup(struct usb_hcd *hcd)
if (ret)
return ret;
- /* workaround only for mt8195 */
- xhci_mtk_set_frame_interval(mtk);
+ xhci_mtk_init_quirk(mtk);
}
ret = xhci_gen_setup(hcd, xhci_mtk_quirks);
@@ -527,6 +556,8 @@ static int xhci_mtk_probe(struct platform_device *pdev)
of_property_read_u32(node, "mediatek,u2p-dis-msk",
&mtk->u2p_dis_msk);
+ mtk->rxfifo_depth_quirk = of_property_read_bool(node, "mediatek,rxfifo-depth");
+
ret = usb_wakeup_of_property_parse(mtk, node);
if (ret) {
dev_err(dev, "failed to parse uwk property\n");
diff --git a/drivers/usb/host/xhci-mtk.h b/drivers/usb/host/xhci-mtk.h
index 39f7ae7d3087..2443075530e3 100644
--- a/drivers/usb/host/xhci-mtk.h
+++ b/drivers/usb/host/xhci-mtk.h
@@ -166,6 +166,7 @@ struct xhci_hcd_mtk {
unsigned int has_ippc:1;
unsigned int lpm_support:1;
unsigned int u2_lpm_disable:1;
+ unsigned int rxfifo_depth_quirk:1;
/* usb remote wakeup */
unsigned int uwk_en:1;
struct regmap *uwk;
--
2.25.1
