Messages in this thread | | | From | Linus Walleij <> | Date | Mon, 22 Aug 2022 11:00:40 +0200 | Subject | Re: [PATCH v3] gpio: realtek-otto: switch to 32-bit I/O |
| |
On Sun, Aug 7, 2022 at 9:21 PM Sander Vanheule <sander@svanheule.net> wrote:
> By using 16-bit I/O on the GPIO peripheral, which is apparently not safe > on MIPS, the IMR can end up containing garbage. This then results in > interrupt triggers for lines that don't have an interrupt handler > associated. The irq_desc lookup fails, and the ISR will not be cleared, > keeping the CPU busy until reboot, or until another IMR operation > restores the correct value. This situation appears to happen very > rarely, for < 0.5% of IMR writes. > > Instead of using 8-bit or 16-bit I/O operations on the 32-bit memory > mapped peripheral registers, switch to using 32-bit I/O only, operating > on the entire bank for all single bit line settings. For 2-bit line > settings, with 16-bit port values, stick to manual (un)packing. > > This issue has been seen on RTL8382M (HPE 1920-16G), RTL8391M (Netgear > GS728TP v2), and RTL8393M (D-Link DGS-1210-52 F3, Zyxel GS1900-48). > > Reported-by: Luiz Angelo Daros de Luca <luizluca@gmail.com> # DGS-1210-52 > Reported-by: Birger Koblitz <mail@birger-koblitz.de> # GS728TP > Reported-by: Jan Hoffmann <jan@3e8.eu> # 1920-16G > Fixes: 0d82fb1127fb ("gpio: Add Realtek Otto GPIO support") > Signed-off-by: Sander Vanheule <sander@svanheule.net> > Cc: Paul Cercueil <paul@crapouillou.net>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Yours, Linus Walleij
| |