Hi Thinh,
On Fri, 2023-07-14 at 21:38 +0000, Thinh Nguyen wrote:
On Fri, Jul 14, 2023, Jakub Vanek wrote:
This reverts commit b138e23d3dff90c0494925b4c1874227b81bddf7.
AutoRetry has been found to sometimes cause controller freezes when communicating with buggy USB devices.
This controller feature allows the controller in host mode to send non-terminating/burst retry ACKs instead of terminating retry ACKs to devices when a transaction error (CRC error or overflow) occurs.
Unfortunately, if the USB device continues to respond with a CRC error, the controller will not complete endpoint-related commands while it keeps trying to auto-retry. [3] The xHCI driver will notice this once it tries to abort the transfer using a Stop Endpoint command and does not receive a completion in time. [1] This situation is reported to dmesg:
[sda] tag#29 uas_eh_abort_handler 0 uas-tag 1 inflight: CMD IN [sda] tag#29 CDB: opcode=0x28 28 00 00 69 42 80 00 00 48 00 xhci-hcd: xHCI host not responding to stop endpoint command xhci-hcd: xHCI host controller not responding, assume dead xhci-hcd: HC died; cleaning up
Some users observed this problem on an Odroid HC2 with the JMS578 USB3-to-SATA bridge. The issue can be triggered by starting a read-heavy workload on an attached SSD. After a while, the host controller would die and the SSD would disappear from the system. [1]
Further analysis by Synopsys determined that controller revisions other than the one in Odroid HC2 are also affected by this. The recommended solution was to disable AutoRetry altogether. This change does not have a noticeable performance impact. [2]
Revert the enablement commit. This will keep the AutoRetry bit in the default state configured during SoC design [2].
Fixes: b138e23d3dff ("usb: dwc3: core: Enable AutoRetry feature in the controller") Link: https://urldefense.com/v3/__https://lore.kernel.org/r/a21f34c04632d250cd0a78... [1] Link: https://urldefense.com/v3/__https://lore.kernel.org/r/20230711214834.kyr6uly... [2] Link: https://urldefense.com/v3/__https://lore.kernel.org/r/20230712225518.2smu7ws... [3] Cc: stable@vger.kernel.org Cc: Mauro Ribeiro mauro.ribeiro@hardkernel.com Cc: Krzysztof Kozlowski krzysztof.kozlowski@linaro.org Suggested-by: Thinh Nguyen Thinh.Nguyen@synopsys.com Signed-off-by: Jakub Vanek linuxtardis@gmail.com
V2 -> V3: Include more findings in changelog V1 -> V2: Updated to disable AutoRetry everywhere based on Synopsys feedback Reworded the changelog a bit to make it clearer
drivers/usb/dwc3/core.c | 16 ---------------- drivers/usb/dwc3/core.h | 3 --- 2 files changed, 19 deletions(-)
diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c index f6689b731718..a4e079d37566 100644 --- a/drivers/usb/dwc3/core.c +++ b/drivers/usb/dwc3/core.c @@ -1209,22 +1209,6 @@ static int dwc3_core_init(struct dwc3 *dwc) dwc3_writel(dwc->regs, DWC3_GUCTL1, reg); } - if (dwc->dr_mode == USB_DR_MODE_HOST || - dwc->dr_mode == USB_DR_MODE_OTG) { - reg = dwc3_readl(dwc->regs, DWC3_GUCTL);
- /* - * Enable Auto retry Feature to make the controller operating in - * Host mode on seeing transaction errors(CRC errors or internal - * overrun scenerios) on IN transfers to reply to the device - * with a non-terminating retry ACK (i.e, an ACK transcation - * packet with Retry=1 & Nump != 0) - */ - reg |= DWC3_GUCTL_HSTINAUTORETRY;
- dwc3_writel(dwc->regs, DWC3_GUCTL, reg); - }
/* * Must config both number of packets and max burst settings to enable * RX and/or TX threshold. diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h index 8b1295e4dcdd..a69ac67d89fe 100644 --- a/drivers/usb/dwc3/core.h +++ b/drivers/usb/dwc3/core.h @@ -256,9 +256,6 @@ #define DWC3_GCTL_GBLHIBERNATIONEN BIT(1) #define DWC3_GCTL_DSBLCLKGTNG BIT(0) -/* Global User Control Register */ -#define DWC3_GUCTL_HSTINAUTORETRY BIT(14)
/* Global User Control 1 Register */ #define DWC3_GUCTL1_DEV_DECOUPLE_L1L2_EVT BIT(31) #define DWC3_GUCTL1_TX_IPGAP_LINECHECK_DIS BIT(28) -- 2.25.1
Acked-by: Thinh Nguyen Thinh.Nguyen@synopsys.com
Thank you!
Thanks, Thinh
Best regards, Jakub