[PATCH v3 19/32] drm/exynos: Use mode_set to configure fimd

[Daniel Kurtz]

Hi Sean, Tomasz,

On Mon, Nov 11, 2013 at 6:03 AM, Tomasz Figa <tomasz.figa at gmail.com> wrote:
> Hi Sean,
>
> On Tuesday 29 of October 2013 12:13:05 Sean Paul wrote:
>> This patch uses the mode passed into mode_set to configure fimd instead
>> of directly using the panel from context. This will allow us to move
>> the exynos_drm_display implementation from fimd into the DP driver
>> where it belongs.
>
> Remember that DP is not the only possible way to connect a display driven
> by FIMD. You also have the direct (RGB and i80) and DSI interfaces.
>
> Also, please see my comments inline.
>
>>
>> Signed-off-by: Sean Paul <seanpaul at chromium.org>
>> ---
>>
>> Changes in v2: None
>> Changes in v3: None
>>
>>  drivers/gpu/drm/exynos/exynos_drm_fimd.c | 159 ++++++++++++++++++-------------
>>  1 file changed, 91 insertions(+), 68 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/exynos/exynos_drm_fimd.c b/drivers/gpu/drm/exynos/exynos_drm_fimd.c
>> index d2b8ccb..f69d6e5 100644
>> --- a/drivers/gpu/drm/exynos/exynos_drm_fimd.c
>> +++ b/drivers/gpu/drm/exynos/exynos_drm_fimd.c
>> @@ -104,6 +104,20 @@ struct fimd_win_data {
>>       bool                    resume;
>>  };
>>
>> +struct fimd_mode_data {
>> +     unsigned                vtotal;
>
> For consistency with rest of the code, unsigned int would prefered.
>
> However, I'm not sure what is this struct for, since it does not store
> neither raw register values (1 needs to be subtracted from them) nor
> any values hard to compute at commit time (maybe except clkdiv, but still
> how often commit would be called?).
>
>> +     unsigned                vdisplay;
>> +     unsigned                vsync_len;
>> +     unsigned                vbpd;
>> +     unsigned                vfpd;
>> +     unsigned                htotal;
>> +     unsigned                hdisplay;
>> +     unsigned                hsync_len;
>> +     unsigned                hbpd;
>> +     unsigned                hfpd;
>> +     u32                     clkdiv;
>> +};
>> +
>>  struct fimd_context {
>>       struct device                   *dev;
>>       struct drm_device               *drm_dev;
>> @@ -112,8 +126,8 @@ struct fimd_context {
>>       struct clk                      *bus_clk;
>>       struct clk                      *lcd_clk;
>>       void __iomem                    *regs;
>> +     struct fimd_mode_data           mode;
>>       struct fimd_win_data            win_data[WINDOWS_NR];
>> -     unsigned int                    clkdiv;
>>       unsigned int                    default_win;
>>       unsigned long                   irq_flags;
>>       u32                             vidcon0;
>> @@ -560,11 +574,56 @@ static void fimd_dpms(struct exynos_drm_manager *mgr, int mode)
>>       mutex_unlock(&ctx->lock);
>>  }
>>
>> +static u32 fimd_calc_clkdiv(struct fimd_context *ctx,
>> +             const struct drm_display_mode *mode)
>> +{
>> +     unsigned long ideal_clk = mode->htotal * mode->vtotal * mode->vrefresh;
>> +     u32 clkdiv;
>> +
>> +     /* Find the clock divider value that gets us closest to ideal_clk */
>> +     clkdiv = DIV_ROUND_CLOSEST(clk_get_rate(ctx->lcd_clk), ideal_clk);
>
> This is a functional change unrelated to $subject. Before this patch,
> DIV_ROUND_UP() had been used.
>
>> +
>> +     return (clkdiv < 0x100) ? clkdiv : 0xff;
>> +}
>> +
>> +static bool fimd_mode_fixup(struct exynos_drm_manager *mgr,
>> +             const struct drm_display_mode *mode,
>> +             struct drm_display_mode *adjusted_mode)
>> +{
>> +     if (adjusted_mode->vrefresh == 0)
>> +             adjusted_mode->vrefresh = FIMD_DEFAULT_FRAMERATE;

The actual pixel clock will be clk_get_rate(ctx->lcd_clk) / clkdiv.
Should we also be adjusting the "clock" field of adjusted_mode here?

>> +
>> +     return true;
>> +}
>> +
>> +static void fimd_mode_set(struct exynos_drm_manager *mgr,
>> +             const struct drm_display_mode *in_mode)
>> +{
>> +     struct fimd_context *ctx = mgr->ctx;
>> +     struct fimd_mode_data *mode = &ctx->mode;
>> +     int hblank, vblank;
>> +
>> +     vblank = in_mode->crtc_vblank_end - in_mode->crtc_vblank_start;
>> +     mode->vtotal = in_mode->crtc_vtotal;
>> +     mode->vdisplay = in_mode->crtc_vdisplay;
>> +     mode->vsync_len = in_mode->crtc_vsync_end - in_mode->crtc_vsync_start;
>> +     mode->vbpd = (vblank - mode->vsync_len) / 2;
>> +     mode->vfpd = vblank - mode->vsync_len - mode->vbpd;
>> +
>> +     hblank = in_mode->crtc_hblank_end - in_mode->crtc_hblank_start;
>> +     mode->htotal = in_mode->crtc_htotal;
>> +     mode->hdisplay = in_mode->crtc_hdisplay;
>> +     mode->hsync_len = in_mode->crtc_hsync_end - in_mode->crtc_hsync_start;
>> +     mode->hbpd = (hblank - mode->hsync_len) / 2;
>> +     mode->hfpd = hblank - mode->hsync_len - mode->hbpd;
>> +
>> +     mode->clkdiv = fimd_calc_clkdiv(ctx, in_mode);
>
> What about simply copying contents of in_mode to driver context
> and then calculating clkdiv at commit time? You could get rid
> of the fimd_mode_data struct and most of this function.
>
> Otherwise, the patch looks fine.
>
> Best regards,
> Tomasz
>
> _______________________________________________
> dri-devel mailing list
> dri-devel at lists.freedesktop.org
> http://lists.freedesktop.org/mailman/listinfo/dri-devel