From: Phil Elwell Date: Wed, 23 Dec 2020 20:35:13 +0000 (+0100) Subject: drm/v3d: Don't clear MMU control bits on exception X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=545d9d780262fcff6ed48dcd812a816cd88e5003;p=linux.git drm/v3d: Don't clear MMU control bits on exception MMU exception conditions are reported in the V3D_MMU_CTRL register as write-1-to-clear (W1C) bits. The MMU interrupt handling code clears any exceptions, but does so by masking out any other bits and writing the result back. There are some important control bits in that register, including MMU_ENABLE, so a safer approach is to simply write back the value just read unaltered. Signed-off-by: Phil Elwell Signed-off-by: Stefan Wahren Reviewed-by: Nicolas Saenz Julienne Signed-off-by: Maxime Ripard Link: https://patchwork.freedesktop.org/patch/msgid/1608755714-18233-4-git-send-email-stefan.wahren@i2se.com --- diff --git a/drivers/gpu/drm/v3d/v3d_irq.c b/drivers/gpu/drm/v3d/v3d_irq.c index 0be2eb7876bed..e714d5318f309 100644 --- a/drivers/gpu/drm/v3d/v3d_irq.c +++ b/drivers/gpu/drm/v3d/v3d_irq.c @@ -178,10 +178,7 @@ v3d_hub_irq(int irq, void *arg) }; const char *client = "?"; - V3D_WRITE(V3D_MMU_CTL, - V3D_READ(V3D_MMU_CTL) & (V3D_MMU_CTL_CAP_EXCEEDED | - V3D_MMU_CTL_PT_INVALID | - V3D_MMU_CTL_WRITE_VIOLATION)); + V3D_WRITE(V3D_MMU_CTL, V3D_READ(V3D_MMU_CTL)); if (v3d->ver >= 41) { axi_id = axi_id >> 5;