[U-Boot] [PATCH 1/2] arm: timer: factor out FSL arch timer erratum workaround

[André Przywara]

Hi,

On 06/29/2018 11:18 AM, Emmanuel Vadot wrote:
> On 2018-06-28 16:37, Andre Przywara wrote:
>> Hi,
>>
>> On 28/06/18 15:27, Jagan Teki wrote:
>>> On Wed, Jun 27, 2018 at 6:12 AM, Andre Przywara
>>> <andre.przywara at arm.com> wrote:
>>>> At the moment we have the workaround for the Freescale arch timer
>>>> erratum A-008585 merged into the generic timer_read_counter() routine.
>>>> Split those two up, so that we can add other errata workaround more
>>>> easily. Also add an explaining comment on the way.
>>>>
>>>> Signed-off-by: Andre Przywara <andre.przywara at arm.com>
>>>> ---
>>>>  arch/arm/cpu/armv8/generic_timer.c | 31
>>>> +++++++++++++++++++++++++------
>>>>  1 file changed, 25 insertions(+), 6 deletions(-)
>>>>
>>>
>>> Are these these two patches are for coming release?
>>
>> Yes, please. That's an issue that needs fixing now. The bug is in all
>> A64 silicon, but the issue popped up with the recent commit 5ff8e54888e4
>> and can be triggered quite easily:
>> Boot mainline U-Boot on any A64 board, and do:
>>> ls mmc 0:1
>> on any SD card (with at least one partition defined). Then hold down the
>> Enter key to repeat this last command over and over again. It usually
>> takes less than 10 seconds to crash the board.
>> People reported immediate crashes under certain circumstances (GPT
>> partitioned SD cards):
>> https://bugzilla.opensuse.org/show_bug.cgi?id=1098550
>>
>> Cheers,
>> Andre.
> 
>  For fixing the issue we also need to add the compat to the timer in the
> dts so kernels will also Apply the errata.
>  Booting is cool but if you boot a kernel that will have timer issue
> it's not that great.

Yes, but that is a separate issue.
The Linux patch [1] is on the list, but hasn't been merged yet. So the
details of the DT property are not yet set.
And since we need the fixup already early in the SPL, we have to use a
compile time option for U-Boot anyway. So the DT property would be
purely for OSes and we would get it during the normal DT sync anyway.

Cheers,
Andre.

[1]
http://lists.infradead.org/pipermail/linux-arm-kernel/2018-May/576886.html