| Message ID | 1486562886-15261-1-git-send-email-jsarha@ti.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Hi Jyri, Thank you for the patch. On Wednesday 08 Feb 2017 16:08:06 Jyri Sarha wrote: > 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. > > Signed-off-by: Jyri Sarha <jsarha@ti.com> Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> > --- > Chnages since first version: > - "color_mode_to_bpp(color_mode) > 8" -> "color_mode != OMAP_DSS_COLOR_NV12" > - commit message and comment updated too > - improve error print > > drivers/gpu/drm/omapdrm/dss/dispc.c | 19 +++++++++++++++++++ > 1 file changed, 19 insertions(+) > > diff --git a/drivers/gpu/drm/omapdrm/dss/dispc.c > b/drivers/gpu/drm/omapdrm/dss/dispc.c index 5554b72..d956e626 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;
On 08/02/17 16:08, Jyri Sarha wrote: > 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. > > Signed-off-by: Jyri Sarha <jsarha@ti.com> > --- > Chnages since first version: > - "color_mode_to_bpp(color_mode) > 8" -> "color_mode != OMAP_DSS_COLOR_NV12" > - commit message and comment updated too > - improve error print > > drivers/gpu/drm/omapdrm/dss/dispc.c | 19 +++++++++++++++++++ > 1 file changed, 19 insertions(+) Thanks, I've picked this up. Tomi
diff --git a/drivers/gpu/drm/omapdrm/dss/dispc.c b/drivers/gpu/drm/omapdrm/dss/dispc.c index 5554b72..d956e626 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;
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. Signed-off-by: Jyri Sarha <jsarha@ti.com> --- Chnages since first version: - "color_mode_to_bpp(color_mode) > 8" -> "color_mode != OMAP_DSS_COLOR_NV12" - commit message and comment updated too - improve error print drivers/gpu/drm/omapdrm/dss/dispc.c | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+)