diff options
Diffstat (limited to 'drivers/gpu/drm/omapdrm/dss/dispc.c')
-rw-r--r-- | drivers/gpu/drm/omapdrm/dss/dispc.c | 19 |
1 files changed, 19 insertions, 0 deletions
diff --git a/drivers/gpu/drm/omapdrm/dss/dispc.c b/drivers/gpu/drm/omapdrm/dss/dispc.c index 5554b72cf56a..d956e6266368 100644 --- a/drivers/gpu/drm/omapdrm/dss/dispc.c +++ b/drivers/gpu/drm/omapdrm/dss/dispc.c @@ -2506,6 +2506,25 @@ static int dispc_ovl_calc_scaling_44xx(unsigned long pclk, unsigned long lclk, return -EINVAL; } + if (*decim_x > 4 && color_mode != OMAP_DSS_COLOR_NV12) { + /* + * Let's disable all scaling that requires horizontal + * decimation with higher factor than 4, until we have + * better estimates of what we can and can not + * do. However, NV12 color format appears to work Ok + * with all decimation factors. + * + * When decimating horizontally by more that 4 the dss + * is not able to fetch the data in burst mode. When + * this happens it is hard to tell if there enough + * bandwidth. Despite what theory says this appears to + * be true also for 16-bit color formats. + */ + DSSERR("Not enough bandwidth, too much downscaling (x-decimation factor %d > 4)", *decim_x); + + return -EINVAL; + } + *core_clk = dispc.feat->calc_core_clk(pclk, in_width, in_height, out_width, out_height, mem_to_mem); return 0; |