diff options
Diffstat (limited to 'drivers/gpu/drm/sun4i/sun4i_backend.c')
-rw-r--r-- | drivers/gpu/drm/sun4i/sun4i_backend.c | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/drivers/gpu/drm/sun4i/sun4i_backend.c b/drivers/gpu/drm/sun4i/sun4i_backend.c index 4fefd8add714..d18d7e88d511 100644 --- a/drivers/gpu/drm/sun4i/sun4i_backend.c +++ b/drivers/gpu/drm/sun4i/sun4i_backend.c @@ -216,6 +216,13 @@ int sun4i_backend_update_layer_buffer(struct sun4i_backend *backend, paddr = drm_fb_cma_get_gem_addr(fb, state, 0); DRM_DEBUG_DRIVER("Setting buffer address to %pad\n", &paddr); + /* + * backend DMA accesses DRAM directly, bypassing the system + * bus. As such, the address range is different and the buffer + * address needs to be corrected. + */ + paddr -= PHYS_OFFSET; + /* Write the 32 lower bits of the address (in bits) */ lo_paddr = paddr << 3; DRM_DEBUG_DRIVER("Setting address lower bits to 0x%x\n", lo_paddr); |