By default when core sees any transaction error(CRC or overflow)
it replies with terminating retry ACK (Retry=1 and Nump == 0).
Enabling this Auto Retry feature in controller, on seeing any
transaction errors makes the core to send a non-terminating ACK
transaction packet (that is, ACK TP with Retry=1 and Nump != 0).
Doing so will give controller a chance to recover from the error
condition.
Signed-off-by: Anurag Kumar Vulisha <[email protected]>
---
Changes in v2:
1. As suggested by Rob Herring & Felipe Balbi removed the
quirk logic and setting the AutoRetry bits unconditionally
for hostmode
---
drivers/usb/dwc3/core.c | 14 ++++++++++++++
drivers/usb/dwc3/core.h | 3 +++
2 files changed, 17 insertions(+)
diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
index 1038075..478c8a6 100644
--- a/drivers/usb/dwc3/core.c
+++ b/drivers/usb/dwc3/core.c
@@ -883,6 +883,20 @@ static int dwc3_core_init(struct dwc3 *dwc)
dwc3_writel(dwc->regs, DWC3_GUCTL1, reg);
}
+ if (dwc->dr_mode == USB_DR_MODE_HOST) {
+ 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 285ce0e..92a1077 100644
--- a/drivers/usb/dwc3/core.h
+++ b/drivers/usb/dwc3/core.h
@@ -227,6 +227,9 @@
#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_TX_IPGAP_LINECHECK_DIS BIT(28)
#define DWC3_GUCTL1_DEV_L1_EXIT_BY_HW BIT(24)
--
2.1.1
Hi,
Anurag Kumar Vulisha <[email protected]> writes:
> By default when core sees any transaction error(CRC or overflow)
> it replies with terminating retry ACK (Retry=1 and Nump == 0).
> Enabling this Auto Retry feature in controller, on seeing any
> transaction errors makes the core to send a non-terminating ACK
> transaction packet (that is, ACK TP with Retry=1 and Nump != 0).
> Doing so will give controller a chance to recover from the error
> condition.
>
> Signed-off-by: Anurag Kumar Vulisha <[email protected]>
> ---
> Changes in v2:
> 1. As suggested by Rob Herring & Felipe Balbi removed the
> quirk logic and setting the AutoRetry bits unconditionally
> for hostmode
> ---
> drivers/usb/dwc3/core.c | 14 ++++++++++++++
> drivers/usb/dwc3/core.h | 3 +++
> 2 files changed, 17 insertions(+)
>
> diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
> index 1038075..478c8a6 100644
> --- a/drivers/usb/dwc3/core.c
> +++ b/drivers/usb/dwc3/core.c
> @@ -883,6 +883,20 @@ static int dwc3_core_init(struct dwc3 *dwc)
> dwc3_writel(dwc->regs, DWC3_GUCTL1, reg);
> }
>
> + if (dwc->dr_mode == USB_DR_MODE_HOST) {
almost there. You also wanna check for dr_mode == OTG. OTG
configurations can switch between device and host mode at will.
> + reg = dwc3_readl(dwc->regs, DWC3_GUCTL);
> +
> + /* Enable Auto retry Feature to make the controller operating in
match the multi-line comment style already in this file:
/*
* Enable Auto ....
--
balbi
Hi Felipe,
Thanks again for reviewing the patch. Will make the suggested changes and send v3.
Thanks,
Anurag Kumar Vulisha
>-----Original Message-----
>From: Felipe Balbi [mailto:[email protected]]
>Sent: Thursday, July 26, 2018 6:12 PM
>To: Anurag Kumar Vulisha <[email protected]>; [email protected]
>Cc: [email protected]; [email protected]; linux-
>[email protected]; Anurag Kumar Vulisha <[email protected]>
>Subject: Re: [PATCH v2] usb: dwc3: core: Add quirk for enabling AutoRetry feature in
>the controller
>
>
>Hi,
>
>Anurag Kumar Vulisha <[email protected]> writes:
>> By default when core sees any transaction error(CRC or overflow) it
>> replies with terminating retry ACK (Retry=1 and Nump == 0).
>> Enabling this Auto Retry feature in controller, on seeing any
>> transaction errors makes the core to send a non-terminating ACK
>> transaction packet (that is, ACK TP with Retry=1 and Nump != 0).
>> Doing so will give controller a chance to recover from the error
>> condition.
>>
>> Signed-off-by: Anurag Kumar Vulisha <[email protected]>
>> ---
>> Changes in v2:
>> 1. As suggested by Rob Herring & Felipe Balbi removed the
>> quirk logic and setting the AutoRetry bits unconditionally
>> for hostmode
>> ---
>> drivers/usb/dwc3/core.c | 14 ++++++++++++++ drivers/usb/dwc3/core.h
>> | 3 +++
>> 2 files changed, 17 insertions(+)
>>
>> diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c index
>> 1038075..478c8a6 100644
>> --- a/drivers/usb/dwc3/core.c
>> +++ b/drivers/usb/dwc3/core.c
>> @@ -883,6 +883,20 @@ static int dwc3_core_init(struct dwc3 *dwc)
>> dwc3_writel(dwc->regs, DWC3_GUCTL1, reg);
>> }
>>
>> + if (dwc->dr_mode == USB_DR_MODE_HOST) {
>
>almost there. You also wanna check for dr_mode == OTG. OTG configurations can
>switch between device and host mode at will.
>
>> + reg = dwc3_readl(dwc->regs, DWC3_GUCTL);
>> +
>> + /* Enable Auto retry Feature to make the controller operating in
>
>match the multi-line comment style already in this file:
>
> /*
> * Enable Auto ....
>
>--
>balbi