From: Phil Elwell <phil@xxxxxxxxxxxxxxx> 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 <phil@xxxxxxxxxxxxxxx> --- drivers/gpu/drm/v3d/v3d_irq.c | 5 +---- 1 file changed, 1 insertion(+), 4 deletions(-) diff --git a/drivers/gpu/drm/v3d/v3d_irq.c b/drivers/gpu/drm/v3d/v3d_irq.c index 0be2eb7..e714d53 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; -- 2.7.4