On 2022-07-18 23:47, Michal Simek wrote:
Hi,

On 7/18/22 18:23, Angus Ainslie wrote:
Hi,

On 2022-07-18 01:13, Michal Simek wrote:
On 7/17/22 17:23, Marek Vasut wrote:
On 7/17/22 05:00, Angus Ainslie wrote:
On 2022-07-16 11:37, Marek Vasut wrote:
On 7/16/22 15:02, Angus Ainslie wrote:
Hi Michal,

I recently rebased my librem5 tree onto the latest u-boot-imx branch
and the dwc3 host mode stopped working.

I bisected it down to this commit:

142d50fbce7c364a74f5e8204dba491b9f066e6c usb: dwc3: Add support for
usb3-phy PHY configuration

Reverting that commit allows usb host mode to work on the librem5 again.

Should this initialization go into an SOC specific glue_configure
function ?

Is the imx8mq.dtsi missing something that will keep usb host working
with this patch ?

Does this break usb host on other imx8mq devices ?

Wasn't this fixed by:
868d58f69c ("usb: dwc3: Fix non-usb3 configurations")
?

I've got that in my tree and it still fails to probe the USB2 hub and
USB 2 storage.

I assume you do have CONFIG_PHY_IMX8MQ_USB enabled ?

What does generic_phy_get_by_name() return for you in
drivers/usb/dwc3/dwc3-generic.c ?

As Marek said there was one patch which fixes origin patch which
didn't handle all the error cases properly. We need to know return
value from generic_phy_get_by_name(), also if you still have usb3-phy
in DT (as is in imx8mq.dtsi) with phy DT status enabled and enabled
phy driver (CONFIG_PHY_IMX8MQ_USB).


Removing the usb3 phy definition also "fixes" it

--- a/arch/arm/dts/imx8mq-librem5-r4.dts
+++ b/arch/arm/dts/imx8mq-librem5-r4.dts
@@ -33,3 +33,8 @@
  &proximity {
         proximity-near-level = <10>;
  };
+
+&usb_dwc3_1 {
+       phys = <&usb3_phy1>;
+       phy-names = "usb2-phy";
+};

Log shows that phy initialization is called properly but it looks like
that initialization itself has issue which should be the issue with
phy driver.

DWC3 driver is calling just phy_init and phy_power_on which are quite
small 2 functions in phy-imx8mq-usb.c.

Did usb3 work before 142d50fbce7c364a74f5e8204dba491b9f066e6c?
I have no idea how imx is working but I have added to CC author of
this phy driver.


We don't use USB3 on that port so no idea. The only thing connected to that port is a USB 2 hub and then downstream devices from the hub. The USB 2 hub did work without 142d50fbce7c364a74f5e8204dba491b9f066e6c.

I see small differences between Linux and U-Boot drivers.

 99         value &= ~PHY_CTRL0_SSC_RANGE_MASK;
100         value |= PHY_CTRL0_SSC_RANGE_4003PPM;

And in power_on I see this in u-boot

129         /* Disable rx term override */
130         value = readl(imx_phy->base + PHY_CTRL6);
131         value &= ~PHY_CTRL6_RXTERM_OVERRIDE_SEL;
132         writel(value, imx_phy->base + PHY_CTRL6);

And Linux driver is handling regulators. Do you use any regulator?

There isn't a regulator specifically for the PHY. There is one for the hub and it gets enabled before the phy_init functions.


If usb3.0 works in Linux I think it should be easier for you to track
this down but there are some small differences in the U-Boot driver
which can be the reason why it is failing on your board.

Thanks
Angus


Thanks,
Michal

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