diff mbox series

[14/23] drm/sun4i: Create minimal multipliers and dividers

Message ID 1234a449a08131a74a3f4851f45458fa9b84ab5e.1508231063.git-series.maxime.ripard@free-electrons.com
State Superseded
Headers show
Series None | expand

Commit Message

Maxime Ripard Oct. 17, 2017, 9:06 a.m. UTC
The various outputs the TCON can provide have different constraints on the
dotclock divider. Let's make them configurable by the various mode_set
functions.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>

---
 drivers/gpu/drm/sun4i/sun4i_dotclock.c | 10 +++++++---
 drivers/gpu/drm/sun4i/sun4i_tcon.c     |  2 ++
 drivers/gpu/drm/sun4i/sun4i_tcon.h     |  2 ++
 3 files changed, 11 insertions(+), 3 deletions(-)

-- 
git-series 0.9.1

Comments

Jonathan Liu Oct. 24, 2017, 2:12 a.m. UTC | #1
Hi Maxime,

On 17 October 2017 at 20:06, Maxime Ripard
<maxime.ripard@free-electrons.com> wrote:
> The various outputs the TCON can provide have different constraints on the

> dotclock divider. Let's make them configurable by the various mode_set

> functions.

>

> Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>

> Reviewed-by: Chen-Yu Tsai <wens@csie.org>

> ---

>  drivers/gpu/drm/sun4i/sun4i_dotclock.c | 10 +++++++---

>  drivers/gpu/drm/sun4i/sun4i_tcon.c     |  2 ++

>  drivers/gpu/drm/sun4i/sun4i_tcon.h     |  2 ++

>  3 files changed, 11 insertions(+), 3 deletions(-)

>

> diff --git a/drivers/gpu/drm/sun4i/sun4i_dotclock.c b/drivers/gpu/drm/sun4i/sun4i_dotclock.c

> index d401156490f3..023f39bda633 100644

> --- a/drivers/gpu/drm/sun4i/sun4i_dotclock.c

> +++ b/drivers/gpu/drm/sun4i/sun4i_dotclock.c

> @@ -17,8 +17,9 @@

>  #include "sun4i_dotclock.h"

>

>  struct sun4i_dclk {

> -       struct clk_hw   hw;

> -       struct regmap   *regmap;

> +       struct clk_hw           hw;

> +       struct regmap           *regmap;

> +       struct sun4i_tcon       *tcon;

>  };

>

>  static inline struct sun4i_dclk *hw_to_dclk(struct clk_hw *hw)

> @@ -73,11 +74,13 @@ static unsigned long sun4i_dclk_recalc_rate(struct clk_hw *hw,

>  static long sun4i_dclk_round_rate(struct clk_hw *hw, unsigned long rate,

>                                   unsigned long *parent_rate)

>  {

> +       struct sun4i_dclk *dclk = hw_to_dclk(hw);

> +       struct sun4i_tcon *tcon = dclk->tcon;

>         unsigned long best_parent = 0;

>         u8 best_div = 1;

>         int i;

>

> -       for (i = 6; i <= 127; i++) {

> +       for (i = tcon->dclk_min_div; i <= tcon->dclk_max_div; i++) {

>                 unsigned long ideal = rate * i;

>                 unsigned long rounded;

>

> @@ -167,6 +170,7 @@ int sun4i_dclk_create(struct device *dev, struct sun4i_tcon *tcon)

>         dclk = devm_kzalloc(dev, sizeof(*dclk), GFP_KERNEL);

>         if (!dclk)

>                 return -ENOMEM;

> +       dclk->tcon = tcon;

>

>         init.name = clk_name;

>         init.ops = &sun4i_dclk_ops;

> diff --git a/drivers/gpu/drm/sun4i/sun4i_tcon.c b/drivers/gpu/drm/sun4i/sun4i_tcon.c

> index f69bcdf11cb8..3efa1ab045cd 100644

> --- a/drivers/gpu/drm/sun4i/sun4i_tcon.c

> +++ b/drivers/gpu/drm/sun4i/sun4i_tcon.c

> @@ -177,6 +177,8 @@ static void sun4i_tcon0_mode_set_rgb(struct sun4i_tcon *tcon,

>         u8 clk_delay;

>         u32 val = 0;

>

> +       tcon->dclk_min_div = 6;

> +       tcon->dclk_max_div = 127;

>         sun4i_tcon0_mode_set_common(tcon, mode);

>

>         /* Adjust clock delay */

> diff --git a/drivers/gpu/drm/sun4i/sun4i_tcon.h b/drivers/gpu/drm/sun4i/sun4i_tcon.h

> index f61bf6d83b4a..4141fbd97ddf 100644

> --- a/drivers/gpu/drm/sun4i/sun4i_tcon.h

> +++ b/drivers/gpu/drm/sun4i/sun4i_tcon.h

> @@ -169,6 +169,8 @@ struct sun4i_tcon {

>

>         /* Pixel clock */

>         struct clk                      *dclk;

> +       u8                              dclk_max_div;

> +       u8                              dclk_min_div;

>

>         /* Reset control */

>         struct reset_control            *lcd_rst;


I have 4.3" RGB LCD enabled on sun7i-a20-olinuxino-lime and hdmi
disabled. After applying this patch the LCD no longer turns on.
If I add some debug statements to sun4i_dclk_recalc_rate, it shows
tcon->dclk_min_div and tcon->dclk_max_div are both 0.

Regards,
Jonathan
diff mbox series

Patch

diff --git a/drivers/gpu/drm/sun4i/sun4i_dotclock.c b/drivers/gpu/drm/sun4i/sun4i_dotclock.c
index d401156490f3..023f39bda633 100644
--- a/drivers/gpu/drm/sun4i/sun4i_dotclock.c
+++ b/drivers/gpu/drm/sun4i/sun4i_dotclock.c
@@ -17,8 +17,9 @@ 
 #include "sun4i_dotclock.h"
 
 struct sun4i_dclk {
-	struct clk_hw	hw;
-	struct regmap	*regmap;
+	struct clk_hw		hw;
+	struct regmap		*regmap;
+	struct sun4i_tcon	*tcon;
 };
 
 static inline struct sun4i_dclk *hw_to_dclk(struct clk_hw *hw)
@@ -73,11 +74,13 @@  static unsigned long sun4i_dclk_recalc_rate(struct clk_hw *hw,
 static long sun4i_dclk_round_rate(struct clk_hw *hw, unsigned long rate,
 				  unsigned long *parent_rate)
 {
+	struct sun4i_dclk *dclk = hw_to_dclk(hw);
+	struct sun4i_tcon *tcon = dclk->tcon;
 	unsigned long best_parent = 0;
 	u8 best_div = 1;
 	int i;
 
-	for (i = 6; i <= 127; i++) {
+	for (i = tcon->dclk_min_div; i <= tcon->dclk_max_div; i++) {
 		unsigned long ideal = rate * i;
 		unsigned long rounded;
 
@@ -167,6 +170,7 @@  int sun4i_dclk_create(struct device *dev, struct sun4i_tcon *tcon)
 	dclk = devm_kzalloc(dev, sizeof(*dclk), GFP_KERNEL);
 	if (!dclk)
 		return -ENOMEM;
+	dclk->tcon = tcon;
 
 	init.name = clk_name;
 	init.ops = &sun4i_dclk_ops;
diff --git a/drivers/gpu/drm/sun4i/sun4i_tcon.c b/drivers/gpu/drm/sun4i/sun4i_tcon.c
index f69bcdf11cb8..3efa1ab045cd 100644
--- a/drivers/gpu/drm/sun4i/sun4i_tcon.c
+++ b/drivers/gpu/drm/sun4i/sun4i_tcon.c
@@ -177,6 +177,8 @@  static void sun4i_tcon0_mode_set_rgb(struct sun4i_tcon *tcon,
 	u8 clk_delay;
 	u32 val = 0;
 
+	tcon->dclk_min_div = 6;
+	tcon->dclk_max_div = 127;
 	sun4i_tcon0_mode_set_common(tcon, mode);
 
 	/* Adjust clock delay */
diff --git a/drivers/gpu/drm/sun4i/sun4i_tcon.h b/drivers/gpu/drm/sun4i/sun4i_tcon.h
index f61bf6d83b4a..4141fbd97ddf 100644
--- a/drivers/gpu/drm/sun4i/sun4i_tcon.h
+++ b/drivers/gpu/drm/sun4i/sun4i_tcon.h
@@ -169,6 +169,8 @@  struct sun4i_tcon {
 
 	/* Pixel clock */
 	struct clk			*dclk;
+	u8				dclk_max_div;
+	u8				dclk_min_div;
 
 	/* Reset control */
 	struct reset_control		*lcd_rst;