Re: [PATCH] usb: dwc2: use a longer AHB idle timeout in dwc2_core_reset()
From: Felipe Balbi
Date: Wed Jul 03 2019 - 07:38:12 EST
Hi,
Martin Blumenstingl <martin.blumenstingl@xxxxxxxxxxxxxx> writes:
> On Mon, Jul 1, 2019 at 7:54 PM Martin Blumenstingl
> <martin.blumenstingl@xxxxxxxxxxxxxx> wrote:
>>
>> On Mon, Jun 24, 2019 at 7:41 AM Minas Harutyunyan
>> <Minas.Harutyunyan@xxxxxxxxxxxx> wrote:
>> >
>> > On 6/20/2019 9:51 PM, Martin Blumenstingl wrote:
>> > > Use a 10000us AHB idle timeout in dwc2_core_reset() and make it
>> > > consistent with the other "wait for AHB master IDLE state" ocurrences.
>> > >
>> > > This fixes a problem for me where dwc2 would not want to initialize when
>> > > updating to 4.19 on a MIPS Lantiq VRX200 SoC. dwc2 worked fine with
>> > > 4.14.
>> > > Testing on my board shows that it takes 180us until AHB master IDLE
>> > > state is signalled. The very old vendor driver for this SoC (ifxhcd)
>> > > used a 1 second timeout.
>> > > Use the same timeout that is used everywhere when polling for
>> > > GRSTCTL_AHBIDLE instead of using a timeout that "works for one board"
>> > > (180us in my case) to have consistent behavior across the dwc2 driver.
>> > >
>> > > Cc: linux-stable <stable@xxxxxxxxxxxxxxx> # 4.19+
>> > > Signed-off-by: Martin Blumenstingl <martin.blumenstingl@xxxxxxxxxxxxxx>
>> > > ---
>> >
>> > Acked-by: Minas Harutyunyan <hminas@xxxxxxxxxxxx>
>> thank you for reviewing this!
>>
>> is there any chance we can get this fix into Linux 5.3? I know that
>> it's too late for 5.2 so I'm fine with skipping that.
> thank you Felipe for queuing this for v5.3!
> for reference, this patch is now in the usb-for-v5.3-part2 tag: [0]
>
>
> [0] https://git.kernel.org/pub/scm/linux/kernel/git/balbi/usb.git/commit/?h=usb-for-v5.3-part2&id=dfc4fdebc5d62ac4e2fe5428e59b273675515fb2
I'll send pull request soon :-)
--
balbi