Re: [PATCH 1/2] drm/mediatek: Add gamma correction

[Bibby Hsieh]

Hi, Daniel, 

Thank you for your suggestion, I will modify that to use the atomic
color management.

Bibby

On Tue, 2016-06-14 at 07:43 +0200, Daniel Vetter wrote:
> On Tue, Jun 14, 2016 at 10:55:52AM +0800, Bibby Hsieh wrote:
> > Apply gamma function to correct brightness values.
> > It applies arbitrary mapping curve to compensate the
> > incorrect transfer function of the panel.
> > 
> > Signed-off-by: Bibby Hsieh 
> 
> I think it would be much better to use the new atomic color management
> support, which includes gamma. See drm_crtc_enable_color_mgmt.
> -Daniel
> 
> > ---
> >  drivers/gpu/drm/mediatek/mtk_drm_crtc.c |   12 ++
> >  drivers/gpu/drm/mediatek/mtk_drm_crtc.h |1 +
> >  drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c |   56 
> > ++-
> >  drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.h |9 +
> >  4 files changed, 77 insertions(+), 1 deletion(-)
> > 
> > diff --git a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c 
> > b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> > index 24aa3ba..1b38406 100644
> > --- a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> > +++ b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> > @@ -127,6 +127,16 @@ static void mtk_drm_crtc_reset(struct drm_crtc *crtc)
> > state->base.crtc = crtc;
> >  }
> >  
> > +static void mtk_crtc_gamma_set(struct drm_crtc *crtc, u16 *r,
> > +  u16 *g, u16 *b, uint32_t start, uint32_t size)
> > +{
> > +   struct mtk_drm_crtc *mtk_crtc = to_mtk_crtc(crtc);
> > +   unsigned int i;
> > +
> > +   for (i = 0; i < mtk_crtc->ddp_comp_nr; i++)
> > +   mtk_ddp_gamma_set(mtk_crtc->ddp_comp[i], r, g, b, start, size);
> > +}
> > +
> >  static struct drm_crtc_state *mtk_drm_crtc_duplicate_state(struct drm_crtc 
> > *crtc)
> >  {
> > struct mtk_crtc_state *state;
> > @@ -418,6 +428,7 @@ static const struct drm_crtc_funcs mtk_crtc_funcs = {
> > .reset  = mtk_drm_crtc_reset,
> > .atomic_duplicate_state = mtk_drm_crtc_duplicate_state,
> > .atomic_destroy_state   = mtk_drm_crtc_destroy_state,
> > +   .gamma_set  = mtk_crtc_gamma_set,
> >  };
> >  
> >  static const struct drm_crtc_helper_funcs mtk_crtc_helper_funcs = {
> > @@ -569,6 +580,7 @@ int mtk_drm_crtc_create(struct drm_device *drm_dev,
> > if (ret < 0)
> > goto unprepare;
> >  
> > +   drm_mode_crtc_set_gamma_size(_crtc->base, MTK_LUT_SIZE);
> > priv->crtc[pipe] = _crtc->base;
> > priv->num_pipes++;
> >  
> > diff --git a/drivers/gpu/drm/mediatek/mtk_drm_crtc.h 
> > b/drivers/gpu/drm/mediatek/mtk_drm_crtc.h
> > index 81e5566..d332564 100644
> > --- a/drivers/gpu/drm/mediatek/mtk_drm_crtc.h
> > +++ b/drivers/gpu/drm/mediatek/mtk_drm_crtc.h
> > @@ -19,6 +19,7 @@
> >  #include "mtk_drm_plane.h"
> >  
> >  #define OVL_LAYER_NR   4
> > +#define MTK_LUT_SIZE   512
> >  
> >  int mtk_drm_crtc_enable_vblank(struct drm_device *drm, unsigned int pipe);
> >  void mtk_drm_crtc_disable_vblank(struct drm_device *drm, unsigned int 
> > pipe);
> > diff --git a/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c 
> > b/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c
> > index 3970fcf..3fd5141 100644
> > --- a/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c
> > +++ b/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c
> > @@ -24,6 +24,7 @@
> >  #include "mtk_drm_drv.h"
> >  #include "mtk_drm_plane.h"
> >  #include "mtk_drm_ddp_comp.h"
> > +#include "mtk_drm_crtc.h"
> >  
> >  #define DISP_OD_EN 0x
> >  #define DISP_OD_INTEN  0x0008
> > @@ -38,6 +39,18 @@
> >  #define DISP_COLOR_WIDTH   0x0c50
> >  #define DISP_COLOR_HEIGHT  0x0c54
> >  
> > +#define DISP_AAL_EN0x000
> > +#define DISP_AAL_SIZE  0x030
> > +
> > +#define DISP_GAMMA_CFG 0x020
> > +#define DISP_GAMMA_LUT 0x700
> > +
> > +#define LUT_10BIT_MASK 0x3ff
> > +
> > +#define AAL_EN BIT(0)
> > +
> > +#define GAMMA_LUT_EN   BIT(1)
> > +
> >  #defineOD_RELAY_MODE   BIT(0)
> >  
> >  #defineUFO_BYPASS  BIT(2)
> > @@ -76,6 +89,40 @@ static void mtk_ufoe_start(struct mtk_ddp_comp *comp)
> > writel(UFO_BYPASS, comp->regs + DISP_REG_UFO_START);
> >  }
> >  
> > +static void mtk_aal_config(struct mtk_ddp_comp *comp, unsigned int w,
> > +  unsigned int h, unsigned int vrefresh)
> > +{
> > +   writel(h << 16 | w, comp->regs + DISP_AAL_SIZE);
> > +}
> > +
> > +static void mtk_aal_start(struct mtk_ddp_comp *comp)
> > +{
> > +   writel(AAL_EN, comp->regs  + DISP_AAL_EN);
> > +}
> > +
> > +static void mtk_aal_stop(struct mtk_ddp_comp *comp)
> > +{
> > +   writel_relaxed(0x0, comp->regs  + DISP_AAL_EN);
> > +}
> > +
> > +static void mtk_gamma_set(struct mtk_ddp_comp *comp, u16 *r, u16 *g,
> > + u16 *b, uint32_t start, 

Re: [PATCH 1/2] drm/mediatek: Add gamma correction

[Bibby Hsieh]

Hi, Daniel, 

Thank you for your suggestion, I will modify that to use the atomic
color management.

Bibby

On Tue, 2016-06-14 at 07:43 +0200, Daniel Vetter wrote:
> On Tue, Jun 14, 2016 at 10:55:52AM +0800, Bibby Hsieh wrote:
> > Apply gamma function to correct brightness values.
> > It applies arbitrary mapping curve to compensate the
> > incorrect transfer function of the panel.
> > 
> > Signed-off-by: Bibby Hsieh 
> 
> I think it would be much better to use the new atomic color management
> support, which includes gamma. See drm_crtc_enable_color_mgmt.
> -Daniel
> 
> > ---
> >  drivers/gpu/drm/mediatek/mtk_drm_crtc.c |   12 ++
> >  drivers/gpu/drm/mediatek/mtk_drm_crtc.h |1 +
> >  drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c |   56 
> > ++-
> >  drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.h |9 +
> >  4 files changed, 77 insertions(+), 1 deletion(-)
> > 
> > diff --git a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c 
> > b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> > index 24aa3ba..1b38406 100644
> > --- a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> > +++ b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> > @@ -127,6 +127,16 @@ static void mtk_drm_crtc_reset(struct drm_crtc *crtc)
> > state->base.crtc = crtc;
> >  }
> >  
> > +static void mtk_crtc_gamma_set(struct drm_crtc *crtc, u16 *r,
> > +  u16 *g, u16 *b, uint32_t start, uint32_t size)
> > +{
> > +   struct mtk_drm_crtc *mtk_crtc = to_mtk_crtc(crtc);
> > +   unsigned int i;
> > +
> > +   for (i = 0; i < mtk_crtc->ddp_comp_nr; i++)
> > +   mtk_ddp_gamma_set(mtk_crtc->ddp_comp[i], r, g, b, start, size);
> > +}
> > +
> >  static struct drm_crtc_state *mtk_drm_crtc_duplicate_state(struct drm_crtc 
> > *crtc)
> >  {
> > struct mtk_crtc_state *state;
> > @@ -418,6 +428,7 @@ static const struct drm_crtc_funcs mtk_crtc_funcs = {
> > .reset  = mtk_drm_crtc_reset,
> > .atomic_duplicate_state = mtk_drm_crtc_duplicate_state,
> > .atomic_destroy_state   = mtk_drm_crtc_destroy_state,
> > +   .gamma_set  = mtk_crtc_gamma_set,
> >  };
> >  
> >  static const struct drm_crtc_helper_funcs mtk_crtc_helper_funcs = {
> > @@ -569,6 +580,7 @@ int mtk_drm_crtc_create(struct drm_device *drm_dev,
> > if (ret < 0)
> > goto unprepare;
> >  
> > +   drm_mode_crtc_set_gamma_size(_crtc->base, MTK_LUT_SIZE);
> > priv->crtc[pipe] = _crtc->base;
> > priv->num_pipes++;
> >  
> > diff --git a/drivers/gpu/drm/mediatek/mtk_drm_crtc.h 
> > b/drivers/gpu/drm/mediatek/mtk_drm_crtc.h
> > index 81e5566..d332564 100644
> > --- a/drivers/gpu/drm/mediatek/mtk_drm_crtc.h
> > +++ b/drivers/gpu/drm/mediatek/mtk_drm_crtc.h
> > @@ -19,6 +19,7 @@
> >  #include "mtk_drm_plane.h"
> >  
> >  #define OVL_LAYER_NR   4
> > +#define MTK_LUT_SIZE   512
> >  
> >  int mtk_drm_crtc_enable_vblank(struct drm_device *drm, unsigned int pipe);
> >  void mtk_drm_crtc_disable_vblank(struct drm_device *drm, unsigned int 
> > pipe);
> > diff --git a/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c 
> > b/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c
> > index 3970fcf..3fd5141 100644
> > --- a/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c
> > +++ b/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c
> > @@ -24,6 +24,7 @@
> >  #include "mtk_drm_drv.h"
> >  #include "mtk_drm_plane.h"
> >  #include "mtk_drm_ddp_comp.h"
> > +#include "mtk_drm_crtc.h"
> >  
> >  #define DISP_OD_EN 0x
> >  #define DISP_OD_INTEN  0x0008
> > @@ -38,6 +39,18 @@
> >  #define DISP_COLOR_WIDTH   0x0c50
> >  #define DISP_COLOR_HEIGHT  0x0c54
> >  
> > +#define DISP_AAL_EN0x000
> > +#define DISP_AAL_SIZE  0x030
> > +
> > +#define DISP_GAMMA_CFG 0x020
> > +#define DISP_GAMMA_LUT 0x700
> > +
> > +#define LUT_10BIT_MASK 0x3ff
> > +
> > +#define AAL_EN BIT(0)
> > +
> > +#define GAMMA_LUT_EN   BIT(1)
> > +
> >  #defineOD_RELAY_MODE   BIT(0)
> >  
> >  #defineUFO_BYPASS  BIT(2)
> > @@ -76,6 +89,40 @@ static void mtk_ufoe_start(struct mtk_ddp_comp *comp)
> > writel(UFO_BYPASS, comp->regs + DISP_REG_UFO_START);
> >  }
> >  
> > +static void mtk_aal_config(struct mtk_ddp_comp *comp, unsigned int w,
> > +  unsigned int h, unsigned int vrefresh)
> > +{
> > +   writel(h << 16 | w, comp->regs + DISP_AAL_SIZE);
> > +}
> > +
> > +static void mtk_aal_start(struct mtk_ddp_comp *comp)
> > +{
> > +   writel(AAL_EN, comp->regs  + DISP_AAL_EN);
> > +}
> > +
> > +static void mtk_aal_stop(struct mtk_ddp_comp *comp)
> > +{
> > +   writel_relaxed(0x0, comp->regs  + DISP_AAL_EN);
> > +}
> > +
> > +static void mtk_gamma_set(struct mtk_ddp_comp *comp, u16 *r, u16 *g,
> > + u16 *b, uint32_t start, uint32_t size)
> > +{
> > +  

Re: [PATCH 1/2] drm/mediatek: Add gamma correction

[Daniel Vetter]

On Tue, Jun 14, 2016 at 10:55:52AM +0800, Bibby Hsieh wrote:
> Apply gamma function to correct brightness values.
> It applies arbitrary mapping curve to compensate the
> incorrect transfer function of the panel.
> 
> Signed-off-by: Bibby Hsieh 

I think it would be much better to use the new atomic color management
support, which includes gamma. See drm_crtc_enable_color_mgmt.
-Daniel

> ---
>  drivers/gpu/drm/mediatek/mtk_drm_crtc.c |   12 ++
>  drivers/gpu/drm/mediatek/mtk_drm_crtc.h |1 +
>  drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c |   56 
> ++-
>  drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.h |9 +
>  4 files changed, 77 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c 
> b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> index 24aa3ba..1b38406 100644
> --- a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> +++ b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> @@ -127,6 +127,16 @@ static void mtk_drm_crtc_reset(struct drm_crtc *crtc)
>   state->base.crtc = crtc;
>  }
>  
> +static void mtk_crtc_gamma_set(struct drm_crtc *crtc, u16 *r,
> +u16 *g, u16 *b, uint32_t start, uint32_t size)
> +{
> + struct mtk_drm_crtc *mtk_crtc = to_mtk_crtc(crtc);
> + unsigned int i;
> +
> + for (i = 0; i < mtk_crtc->ddp_comp_nr; i++)
> + mtk_ddp_gamma_set(mtk_crtc->ddp_comp[i], r, g, b, start, size);
> +}
> +
>  static struct drm_crtc_state *mtk_drm_crtc_duplicate_state(struct drm_crtc 
> *crtc)
>  {
>   struct mtk_crtc_state *state;
> @@ -418,6 +428,7 @@ static const struct drm_crtc_funcs mtk_crtc_funcs = {
>   .reset  = mtk_drm_crtc_reset,
>   .atomic_duplicate_state = mtk_drm_crtc_duplicate_state,
>   .atomic_destroy_state   = mtk_drm_crtc_destroy_state,
> + .gamma_set  = mtk_crtc_gamma_set,
>  };
>  
>  static const struct drm_crtc_helper_funcs mtk_crtc_helper_funcs = {
> @@ -569,6 +580,7 @@ int mtk_drm_crtc_create(struct drm_device *drm_dev,
>   if (ret < 0)
>   goto unprepare;
>  
> + drm_mode_crtc_set_gamma_size(_crtc->base, MTK_LUT_SIZE);
>   priv->crtc[pipe] = _crtc->base;
>   priv->num_pipes++;
>  
> diff --git a/drivers/gpu/drm/mediatek/mtk_drm_crtc.h 
> b/drivers/gpu/drm/mediatek/mtk_drm_crtc.h
> index 81e5566..d332564 100644
> --- a/drivers/gpu/drm/mediatek/mtk_drm_crtc.h
> +++ b/drivers/gpu/drm/mediatek/mtk_drm_crtc.h
> @@ -19,6 +19,7 @@
>  #include "mtk_drm_plane.h"
>  
>  #define OVL_LAYER_NR 4
> +#define MTK_LUT_SIZE 512
>  
>  int mtk_drm_crtc_enable_vblank(struct drm_device *drm, unsigned int pipe);
>  void mtk_drm_crtc_disable_vblank(struct drm_device *drm, unsigned int pipe);
> diff --git a/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c 
> b/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c
> index 3970fcf..3fd5141 100644
> --- a/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c
> +++ b/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c
> @@ -24,6 +24,7 @@
>  #include "mtk_drm_drv.h"
>  #include "mtk_drm_plane.h"
>  #include "mtk_drm_ddp_comp.h"
> +#include "mtk_drm_crtc.h"
>  
>  #define DISP_OD_EN   0x
>  #define DISP_OD_INTEN0x0008
> @@ -38,6 +39,18 @@
>  #define DISP_COLOR_WIDTH 0x0c50
>  #define DISP_COLOR_HEIGHT0x0c54
>  
> +#define DISP_AAL_EN  0x000
> +#define DISP_AAL_SIZE0x030
> +
> +#define DISP_GAMMA_CFG   0x020
> +#define DISP_GAMMA_LUT   0x700
> +
> +#define LUT_10BIT_MASK   0x3ff
> +
> +#define AAL_EN   BIT(0)
> +
> +#define GAMMA_LUT_EN BIT(1)
> +
>  #define  OD_RELAY_MODE   BIT(0)
>  
>  #define  UFO_BYPASS  BIT(2)
> @@ -76,6 +89,40 @@ static void mtk_ufoe_start(struct mtk_ddp_comp *comp)
>   writel(UFO_BYPASS, comp->regs + DISP_REG_UFO_START);
>  }
>  
> +static void mtk_aal_config(struct mtk_ddp_comp *comp, unsigned int w,
> +unsigned int h, unsigned int vrefresh)
> +{
> + writel(h << 16 | w, comp->regs + DISP_AAL_SIZE);
> +}
> +
> +static void mtk_aal_start(struct mtk_ddp_comp *comp)
> +{
> + writel(AAL_EN, comp->regs  + DISP_AAL_EN);
> +}
> +
> +static void mtk_aal_stop(struct mtk_ddp_comp *comp)
> +{
> + writel_relaxed(0x0, comp->regs  + DISP_AAL_EN);
> +}
> +
> +static void mtk_gamma_set(struct mtk_ddp_comp *comp, u16 *r, u16 *g,
> +   u16 *b, uint32_t start, uint32_t size)
> +{
> + int i;
> + unsigned int lut;
> + int end = (start + size > MTK_LUT_SIZE) ? MTK_LUT_SIZE : start + size;
> + void __iomem *lut_base;
> +
> + writel(GAMMA_LUT_EN, comp->regs + DISP_GAMMA_CFG);
> + lut_base = comp->regs + DISP_GAMMA_LUT;
> + for (i = start; i < end; i++) {
> + lut = (((r[i] >> 6) & LUT_10BIT_MASK) << 

Re: [PATCH 1/2] drm/mediatek: Add gamma correction

[Daniel Vetter]

On Tue, Jun 14, 2016 at 10:55:52AM +0800, Bibby Hsieh wrote:
> Apply gamma function to correct brightness values.
> It applies arbitrary mapping curve to compensate the
> incorrect transfer function of the panel.
> 
> Signed-off-by: Bibby Hsieh 

I think it would be much better to use the new atomic color management
support, which includes gamma. See drm_crtc_enable_color_mgmt.
-Daniel

> ---
>  drivers/gpu/drm/mediatek/mtk_drm_crtc.c |   12 ++
>  drivers/gpu/drm/mediatek/mtk_drm_crtc.h |1 +
>  drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c |   56 
> ++-
>  drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.h |9 +
>  4 files changed, 77 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c 
> b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> index 24aa3ba..1b38406 100644
> --- a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> +++ b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> @@ -127,6 +127,16 @@ static void mtk_drm_crtc_reset(struct drm_crtc *crtc)
>   state->base.crtc = crtc;
>  }
>  
> +static void mtk_crtc_gamma_set(struct drm_crtc *crtc, u16 *r,
> +u16 *g, u16 *b, uint32_t start, uint32_t size)
> +{
> + struct mtk_drm_crtc *mtk_crtc = to_mtk_crtc(crtc);
> + unsigned int i;
> +
> + for (i = 0; i < mtk_crtc->ddp_comp_nr; i++)
> + mtk_ddp_gamma_set(mtk_crtc->ddp_comp[i], r, g, b, start, size);
> +}
> +
>  static struct drm_crtc_state *mtk_drm_crtc_duplicate_state(struct drm_crtc 
> *crtc)
>  {
>   struct mtk_crtc_state *state;
> @@ -418,6 +428,7 @@ static const struct drm_crtc_funcs mtk_crtc_funcs = {
>   .reset  = mtk_drm_crtc_reset,
>   .atomic_duplicate_state = mtk_drm_crtc_duplicate_state,
>   .atomic_destroy_state   = mtk_drm_crtc_destroy_state,
> + .gamma_set  = mtk_crtc_gamma_set,
>  };
>  
>  static const struct drm_crtc_helper_funcs mtk_crtc_helper_funcs = {
> @@ -569,6 +580,7 @@ int mtk_drm_crtc_create(struct drm_device *drm_dev,
>   if (ret < 0)
>   goto unprepare;
>  
> + drm_mode_crtc_set_gamma_size(_crtc->base, MTK_LUT_SIZE);
>   priv->crtc[pipe] = _crtc->base;
>   priv->num_pipes++;
>  
> diff --git a/drivers/gpu/drm/mediatek/mtk_drm_crtc.h 
> b/drivers/gpu/drm/mediatek/mtk_drm_crtc.h
> index 81e5566..d332564 100644
> --- a/drivers/gpu/drm/mediatek/mtk_drm_crtc.h
> +++ b/drivers/gpu/drm/mediatek/mtk_drm_crtc.h
> @@ -19,6 +19,7 @@
>  #include "mtk_drm_plane.h"
>  
>  #define OVL_LAYER_NR 4
> +#define MTK_LUT_SIZE 512
>  
>  int mtk_drm_crtc_enable_vblank(struct drm_device *drm, unsigned int pipe);
>  void mtk_drm_crtc_disable_vblank(struct drm_device *drm, unsigned int pipe);
> diff --git a/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c 
> b/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c
> index 3970fcf..3fd5141 100644
> --- a/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c
> +++ b/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c
> @@ -24,6 +24,7 @@
>  #include "mtk_drm_drv.h"
>  #include "mtk_drm_plane.h"
>  #include "mtk_drm_ddp_comp.h"
> +#include "mtk_drm_crtc.h"
>  
>  #define DISP_OD_EN   0x
>  #define DISP_OD_INTEN0x0008
> @@ -38,6 +39,18 @@
>  #define DISP_COLOR_WIDTH 0x0c50
>  #define DISP_COLOR_HEIGHT0x0c54
>  
> +#define DISP_AAL_EN  0x000
> +#define DISP_AAL_SIZE0x030
> +
> +#define DISP_GAMMA_CFG   0x020
> +#define DISP_GAMMA_LUT   0x700
> +
> +#define LUT_10BIT_MASK   0x3ff
> +
> +#define AAL_EN   BIT(0)
> +
> +#define GAMMA_LUT_EN BIT(1)
> +
>  #define  OD_RELAY_MODE   BIT(0)
>  
>  #define  UFO_BYPASS  BIT(2)
> @@ -76,6 +89,40 @@ static void mtk_ufoe_start(struct mtk_ddp_comp *comp)
>   writel(UFO_BYPASS, comp->regs + DISP_REG_UFO_START);
>  }
>  
> +static void mtk_aal_config(struct mtk_ddp_comp *comp, unsigned int w,
> +unsigned int h, unsigned int vrefresh)
> +{
> + writel(h << 16 | w, comp->regs + DISP_AAL_SIZE);
> +}
> +
> +static void mtk_aal_start(struct mtk_ddp_comp *comp)
> +{
> + writel(AAL_EN, comp->regs  + DISP_AAL_EN);
> +}
> +
> +static void mtk_aal_stop(struct mtk_ddp_comp *comp)
> +{
> + writel_relaxed(0x0, comp->regs  + DISP_AAL_EN);
> +}
> +
> +static void mtk_gamma_set(struct mtk_ddp_comp *comp, u16 *r, u16 *g,
> +   u16 *b, uint32_t start, uint32_t size)
> +{
> + int i;
> + unsigned int lut;
> + int end = (start + size > MTK_LUT_SIZE) ? MTK_LUT_SIZE : start + size;
> + void __iomem *lut_base;
> +
> + writel(GAMMA_LUT_EN, comp->regs + DISP_GAMMA_CFG);
> + lut_base = comp->regs + DISP_GAMMA_LUT;
> + for (i = start; i < end; i++) {
> + lut = (((r[i] >> 6) & LUT_10BIT_MASK) << 20) +
> + 

[PATCH 1/2] drm/mediatek: Add gamma correction

[Bibby Hsieh]

Apply gamma function to correct brightness values.
It applies arbitrary mapping curve to compensate the
incorrect transfer function of the panel.

Signed-off-by: Bibby Hsieh 
---
 drivers/gpu/drm/mediatek/mtk_drm_crtc.c |   12 ++
 drivers/gpu/drm/mediatek/mtk_drm_crtc.h |1 +
 drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c |   56 ++-
 drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.h |9 +
 4 files changed, 77 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c 
b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
index 24aa3ba..1b38406 100644
--- a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
+++ b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
@@ -127,6 +127,16 @@ static void mtk_drm_crtc_reset(struct drm_crtc *crtc)
state->base.crtc = crtc;
 }
 
+static void mtk_crtc_gamma_set(struct drm_crtc *crtc, u16 *r,
+  u16 *g, u16 *b, uint32_t start, uint32_t size)
+{
+   struct mtk_drm_crtc *mtk_crtc = to_mtk_crtc(crtc);
+   unsigned int i;
+
+   for (i = 0; i < mtk_crtc->ddp_comp_nr; i++)
+   mtk_ddp_gamma_set(mtk_crtc->ddp_comp[i], r, g, b, start, size);
+}
+
 static struct drm_crtc_state *mtk_drm_crtc_duplicate_state(struct drm_crtc 
*crtc)
 {
struct mtk_crtc_state *state;
@@ -418,6 +428,7 @@ static const struct drm_crtc_funcs mtk_crtc_funcs = {
.reset  = mtk_drm_crtc_reset,
.atomic_duplicate_state = mtk_drm_crtc_duplicate_state,
.atomic_destroy_state   = mtk_drm_crtc_destroy_state,
+   .gamma_set  = mtk_crtc_gamma_set,
 };
 
 static const struct drm_crtc_helper_funcs mtk_crtc_helper_funcs = {
@@ -569,6 +580,7 @@ int mtk_drm_crtc_create(struct drm_device *drm_dev,
if (ret < 0)
goto unprepare;
 
+   drm_mode_crtc_set_gamma_size(_crtc->base, MTK_LUT_SIZE);
priv->crtc[pipe] = _crtc->base;
priv->num_pipes++;
 
diff --git a/drivers/gpu/drm/mediatek/mtk_drm_crtc.h 
b/drivers/gpu/drm/mediatek/mtk_drm_crtc.h
index 81e5566..d332564 100644
--- a/drivers/gpu/drm/mediatek/mtk_drm_crtc.h
+++ b/drivers/gpu/drm/mediatek/mtk_drm_crtc.h
@@ -19,6 +19,7 @@
 #include "mtk_drm_plane.h"
 
 #define OVL_LAYER_NR   4
+#define MTK_LUT_SIZE   512
 
 int mtk_drm_crtc_enable_vblank(struct drm_device *drm, unsigned int pipe);
 void mtk_drm_crtc_disable_vblank(struct drm_device *drm, unsigned int pipe);
diff --git a/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c 
b/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c
index 3970fcf..3fd5141 100644
--- a/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c
+++ b/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c
@@ -24,6 +24,7 @@
 #include "mtk_drm_drv.h"
 #include "mtk_drm_plane.h"
 #include "mtk_drm_ddp_comp.h"
+#include "mtk_drm_crtc.h"
 
 #define DISP_OD_EN 0x
 #define DISP_OD_INTEN  0x0008
@@ -38,6 +39,18 @@
 #define DISP_COLOR_WIDTH   0x0c50
 #define DISP_COLOR_HEIGHT  0x0c54
 
+#define DISP_AAL_EN0x000
+#define DISP_AAL_SIZE  0x030
+
+#define DISP_GAMMA_CFG 0x020
+#define DISP_GAMMA_LUT 0x700
+
+#define LUT_10BIT_MASK 0x3ff
+
+#define AAL_EN BIT(0)
+
+#define GAMMA_LUT_EN   BIT(1)
+
 #defineOD_RELAY_MODE   BIT(0)
 
 #defineUFO_BYPASS  BIT(2)
@@ -76,6 +89,40 @@ static void mtk_ufoe_start(struct mtk_ddp_comp *comp)
writel(UFO_BYPASS, comp->regs + DISP_REG_UFO_START);
 }
 
+static void mtk_aal_config(struct mtk_ddp_comp *comp, unsigned int w,
+  unsigned int h, unsigned int vrefresh)
+{
+   writel(h << 16 | w, comp->regs + DISP_AAL_SIZE);
+}
+
+static void mtk_aal_start(struct mtk_ddp_comp *comp)
+{
+   writel(AAL_EN, comp->regs  + DISP_AAL_EN);
+}
+
+static void mtk_aal_stop(struct mtk_ddp_comp *comp)
+{
+   writel_relaxed(0x0, comp->regs  + DISP_AAL_EN);
+}
+
+static void mtk_gamma_set(struct mtk_ddp_comp *comp, u16 *r, u16 *g,
+ u16 *b, uint32_t start, uint32_t size)
+{
+   int i;
+   unsigned int lut;
+   int end = (start + size > MTK_LUT_SIZE) ? MTK_LUT_SIZE : start + size;
+   void __iomem *lut_base;
+
+   writel(GAMMA_LUT_EN, comp->regs + DISP_GAMMA_CFG);
+   lut_base = comp->regs + DISP_GAMMA_LUT;
+   for (i = start; i < end; i++) {
+   lut = (((r[i] >> 6) & LUT_10BIT_MASK) << 20) +
+   (((g[i] >> 6) & LUT_10BIT_MASK) << 10) +
+   ((b[i] >> 6) & LUT_10BIT_MASK);
+   writel(lut, (lut_base + i * 4));
+   }
+}
+
 static const struct mtk_ddp_comp_funcs ddp_color = {
.config = mtk_color_config,
.start = mtk_color_start,
@@ -90,6 +137,13 @@ static const struct mtk_ddp_comp_funcs ddp_ufoe = {
.start = mtk_ufoe_start,
 

[PATCH 1/2] drm/mediatek: Add gamma correction

[Bibby Hsieh]

Apply gamma function to correct brightness values.
It applies arbitrary mapping curve to compensate the
incorrect transfer function of the panel.

Signed-off-by: Bibby Hsieh 
---
 drivers/gpu/drm/mediatek/mtk_drm_crtc.c |   12 ++
 drivers/gpu/drm/mediatek/mtk_drm_crtc.h |1 +
 drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c |   56 ++-
 drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.h |9 +
 4 files changed, 77 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c 
b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
index 24aa3ba..1b38406 100644
--- a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
+++ b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
@@ -127,6 +127,16 @@ static void mtk_drm_crtc_reset(struct drm_crtc *crtc)
state->base.crtc = crtc;
 }
 
+static void mtk_crtc_gamma_set(struct drm_crtc *crtc, u16 *r,
+  u16 *g, u16 *b, uint32_t start, uint32_t size)
+{
+   struct mtk_drm_crtc *mtk_crtc = to_mtk_crtc(crtc);
+   unsigned int i;
+
+   for (i = 0; i < mtk_crtc->ddp_comp_nr; i++)
+   mtk_ddp_gamma_set(mtk_crtc->ddp_comp[i], r, g, b, start, size);
+}
+
 static struct drm_crtc_state *mtk_drm_crtc_duplicate_state(struct drm_crtc 
*crtc)
 {
struct mtk_crtc_state *state;
@@ -418,6 +428,7 @@ static const struct drm_crtc_funcs mtk_crtc_funcs = {
.reset  = mtk_drm_crtc_reset,
.atomic_duplicate_state = mtk_drm_crtc_duplicate_state,
.atomic_destroy_state   = mtk_drm_crtc_destroy_state,
+   .gamma_set  = mtk_crtc_gamma_set,
 };
 
 static const struct drm_crtc_helper_funcs mtk_crtc_helper_funcs = {
@@ -569,6 +580,7 @@ int mtk_drm_crtc_create(struct drm_device *drm_dev,
if (ret < 0)
goto unprepare;
 
+   drm_mode_crtc_set_gamma_size(_crtc->base, MTK_LUT_SIZE);
priv->crtc[pipe] = _crtc->base;
priv->num_pipes++;
 
diff --git a/drivers/gpu/drm/mediatek/mtk_drm_crtc.h 
b/drivers/gpu/drm/mediatek/mtk_drm_crtc.h
index 81e5566..d332564 100644
--- a/drivers/gpu/drm/mediatek/mtk_drm_crtc.h
+++ b/drivers/gpu/drm/mediatek/mtk_drm_crtc.h
@@ -19,6 +19,7 @@
 #include "mtk_drm_plane.h"
 
 #define OVL_LAYER_NR   4
+#define MTK_LUT_SIZE   512
 
 int mtk_drm_crtc_enable_vblank(struct drm_device *drm, unsigned int pipe);
 void mtk_drm_crtc_disable_vblank(struct drm_device *drm, unsigned int pipe);
diff --git a/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c 
b/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c
index 3970fcf..3fd5141 100644
--- a/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c
+++ b/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c
@@ -24,6 +24,7 @@
 #include "mtk_drm_drv.h"
 #include "mtk_drm_plane.h"
 #include "mtk_drm_ddp_comp.h"
+#include "mtk_drm_crtc.h"
 
 #define DISP_OD_EN 0x
 #define DISP_OD_INTEN  0x0008
@@ -38,6 +39,18 @@
 #define DISP_COLOR_WIDTH   0x0c50
 #define DISP_COLOR_HEIGHT  0x0c54
 
+#define DISP_AAL_EN0x000
+#define DISP_AAL_SIZE  0x030
+
+#define DISP_GAMMA_CFG 0x020
+#define DISP_GAMMA_LUT 0x700
+
+#define LUT_10BIT_MASK 0x3ff
+
+#define AAL_EN BIT(0)
+
+#define GAMMA_LUT_EN   BIT(1)
+
 #defineOD_RELAY_MODE   BIT(0)
 
 #defineUFO_BYPASS  BIT(2)
@@ -76,6 +89,40 @@ static void mtk_ufoe_start(struct mtk_ddp_comp *comp)
writel(UFO_BYPASS, comp->regs + DISP_REG_UFO_START);
 }
 
+static void mtk_aal_config(struct mtk_ddp_comp *comp, unsigned int w,
+  unsigned int h, unsigned int vrefresh)
+{
+   writel(h << 16 | w, comp->regs + DISP_AAL_SIZE);
+}
+
+static void mtk_aal_start(struct mtk_ddp_comp *comp)
+{
+   writel(AAL_EN, comp->regs  + DISP_AAL_EN);
+}
+
+static void mtk_aal_stop(struct mtk_ddp_comp *comp)
+{
+   writel_relaxed(0x0, comp->regs  + DISP_AAL_EN);
+}
+
+static void mtk_gamma_set(struct mtk_ddp_comp *comp, u16 *r, u16 *g,
+ u16 *b, uint32_t start, uint32_t size)
+{
+   int i;
+   unsigned int lut;
+   int end = (start + size > MTK_LUT_SIZE) ? MTK_LUT_SIZE : start + size;
+   void __iomem *lut_base;
+
+   writel(GAMMA_LUT_EN, comp->regs + DISP_GAMMA_CFG);
+   lut_base = comp->regs + DISP_GAMMA_LUT;
+   for (i = start; i < end; i++) {
+   lut = (((r[i] >> 6) & LUT_10BIT_MASK) << 20) +
+   (((g[i] >> 6) & LUT_10BIT_MASK) << 10) +
+   ((b[i] >> 6) & LUT_10BIT_MASK);
+   writel(lut, (lut_base + i * 4));
+   }
+}
+
 static const struct mtk_ddp_comp_funcs ddp_color = {
.config = mtk_color_config,
.start = mtk_color_start,
@@ -90,6 +137,13 @@ static const struct mtk_ddp_comp_funcs ddp_ufoe = {
.start = mtk_ufoe_start,
 };
 
+static const struct