On Wed, Jun 27, 2018 at 6:12 AM, Andre Przywara andre.przywara@arm.com wrote:
The Allwinner A64 SoCs suffers from an arch timer implementation erratum, where sometimes the lower 11 bits of the counter value erroneously become all 0's or all 1's [1]. This leads to sudden jumps, both forwards and backwards, with the latter one often showing weird behaviour. Port the workaround proposed for Linux to U-Boot and activate it for all A64 boards. This fixes crashes when accessing MMC devices (SD cards), caused by a recent change to actually use the counter value for timeout checks.
Fixes: 5ff8e54888e4d26a352453564f7f599d29696dc9 ("sunxi: improve throughput in the sunxi_mmc driver")
[1] http://lists.infradead.org/pipermail/linux-arm-kernel/2018-May/576886.html
Signed-off-by: Andre Przywara andre.przywara@arm.com
Tested-by: Jagan Teki jagan@amarulasolutions.com