@@ -1120,6 +1120,7 @@ static int cdns3_ep_run_transfer(struct cdns3_endpoint *priv_ep,
u32 togle_pcs = 1;
int sg_iter = 0;
int num_trb_req;
+ int trb_burst;
int num_trb;
int address;
u32 control;
@@ -1243,7 +1244,36 @@ static int cdns3_ep_run_transfer(struct cdns3_endpoint *priv_ep,
total_tdl += DIV_ROUND_UP(length,
priv_ep->endpoint.maxpacket);
- trb->length |= cpu_to_le32(TRB_BURST_LEN(priv_ep->trb_burst_size) |
+ trb_burst = priv_ep->trb_burst_size;
+
+ /*
+ * Supposed DMA cross 4k bounder problem should be fixed at DEV_VER_V2, but still
+ * met problem when do ISO transfer if sg enabled.
+ *
+ * Data pattern likes below when sg enabled, package size is 1k and mult is 2
+ * [UVC Header(8B) ] [data(3k - 8)] ...
+ *
+ * The received data at offset 0xd000 will get 0xc000 data, len 0x70. Error happen
+ * as below pattern:
+ * 0xd000: wrong
+ * 0xe000: wrong
+ * 0xf000: correct
+ * 0x10000: wrong
+ * 0x11000: wrong
+ * 0x12000: correct
+ * ...
+ *
+ * But it is still unclear about why error have not happen below 0xd000, it should
+ * cross 4k bounder. But anyway, the below code can fix this problem.
+ *
+ * To avoid DMA cross 4k bounder at ISO transfer, reduce burst len according to 16.
+ */
+ if (priv_ep->type == USB_ENDPOINT_XFER_ISOC && priv_dev->dev_ver <= DEV_VER_V2)
+ if (ALIGN_DOWN(trb->buffer, SZ_4K) !=
+ ALIGN_DOWN(trb->buffer + length, SZ_4K))
+ trb_burst = 16;
+
+ trb->length |= cpu_to_le32(TRB_BURST_LEN(trb_burst) |
TRB_LEN(length));
pcs = priv_ep->pcs ? TRB_CYCLE : 0;
Supposed DMA cross 4k bounder problem should be fixed at DEV_VER_V2, but still met problem when do ISO transfer if sg enabled. Data pattern likes below when sg enabled, package size is 1k and mult is 2 [UVC Header(8B) ] [data(3k - 8)] ... The received data at offset 0xd000 will get 0xc000 data, len 0x70. Error happen position as below pattern: 0xd000: wrong 0xe000: wrong 0xf000: correct 0x10000: wrong 0x11000: wrong 0x12000: correct ... To avoid DMA cross 4k bounder at ISO transfer, reduce burst len according to start DMA address's alignment. Cc: stable@vger.kernel.org Fixes: 7733f6c32e36 ("usb: cdns3: Add Cadence USB3 DRD Driver") Signed-off-by: Frank Li <Frank.Li@nxp.com> --- drivers/usb/cdns3/cdns3-gadget.c | 32 +++++++++++++++++++++++++++++++- 1 file changed, 31 insertions(+), 1 deletion(-)