[PATCH 2/6] drm/radeon: ATOM Endian fix for atombios_crtc_program_pll()

[Alex Deucher]

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);
>
>
>
>