On Wed, Jul 13, 2011 at 2:28 AM, Benjamin Herrenschmidt <benh at kernel.crashing.org> wrote: > v6 of the structure was programmed incorrectly: > > ?args.v6.ulCrtcPclkFreq.ulPixelClock = cpu_to_le32(clock / 10); > > ulPixelClock is a 24-bit bitfield. This statement would thus > do a 32-bit swap of (clock / 10) and drop the top 8 bits which > are ... the LSB. Not what we want. Instead use masks & shifts. > > Signed-off-by: Benjamin Herrenschmidt <benh at kernel.crashing.org> > --- > > (resent adding dri-devel to the CC list to hit patchwork) > > ?drivers/gpu/drm/radeon/atombios_crtc.c | ? ?5 ++--- > ?1 files changed, 2 insertions(+), 3 deletions(-) > > diff --git a/drivers/gpu/drm/radeon/atombios_crtc.c > b/drivers/gpu/drm/radeon/atombios_crtc.c > index 9541995..c742944 100644 > --- a/drivers/gpu/drm/radeon/atombios_crtc.c > +++ b/drivers/gpu/drm/radeon/atombios_crtc.c > @@ -764,7 +764,7 @@ static void atombios_crtc_set_dcpll(struct drm_crtc *crtc, > ?} > > ?static void atombios_crtc_program_pll(struct drm_crtc *crtc, > - ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? int crtc_id, > + ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? u32 crtc_id, > ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?int pll_id, > ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?u32 encoder_mode, > ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?u32 encoder_id, > @@ -851,8 +851,7 @@ static void atombios_crtc_program_pll(struct drm_crtc > *crtc, > ? ? ? ? ? ? ? ? ? ? ? ?args.v5.ucPpll = pll_id; > ? ? ? ? ? ? ? ? ? ? ? ?break; > ? ? ? ? ? ? ? ?case 6: > - ? ? ? ? ? ? ? ? ? ? ? args.v6.ulCrtcPclkFreq.ucCRTC = crtc_id; > - ? ? ? ? ? ? ? ? ? ? ? args.v6.ulCrtcPclkFreq.ulPixelClock = > cpu_to_le32(clock / 10); > + ? ? ? ? ? ? ? ? ? ? ? args.v6.ulDispEngClkFreq = cpu_to_le32(crtc_id << 24 > | clock / 10);
For clarity (i can never remember op precedence), you might put: cpu_to_le32((crtc_id << 24) | (clock / 10)); Other than that, Reviewed-by: Alex Deucher <alexander.deucher at amd.com> > ? ? ? ? ? ? ? ? ? ? ? ?args.v6.ucRefDiv = ref_div; > ? ? ? ? ? ? ? ? ? ? ? ?args.v6.usFbDiv = cpu_to_le16(fb_div); > ? ? ? ? ? ? ? ? ? ? ? ?args.v6.ulFbDivDecFrac = cpu_to_le32(frac_fb_div * > 100000); > > > >
