[PATCH] clk: sunxi-ng: enable so-said LDOs for A33 SoC's pll-mipi clock

[PATCH] clk: sunxi-ng: enable so-said LDOs for A33 SoC's pll-mipi clock

[Icenowy Zheng]

In the user manual of A33 SoC, the bit 22 and 23 of pll-mipi control
register is called "LDO{1,2}_EN", and according to the BSP source code
from Allwinner [1], the LDOs are enabled during the clock's enabling
process.

The clock failed to generate output if the two LDOs are not enabled.

Add the two bits to the clock's gate bits, so that the LDOs are enabled
when the PLL is enabled.

[1] https://github.com/allwinner-zh/linux-3.4-sunxi/blob/master/drivers/clk/sunxi/clk-sun8iw5.c#L429

Fixes: d05c748bd730 ("clk: sunxi-ng: Add A33 CCU support")

Signed-off-by: Icenowy Zheng <icenowy@aosc.xyz>
---
Dear Chen-Yu:
As you said, the two bits are also present in the CCU of A23 and A31.
Could you please check whether the PLL works on the two SoCs?
I remembered you mentioned you failed to make TCON enabled on A23.
On A31, you may hack the parent of tcon-ch0 to force the tcon clock to
use pll-mipi as parent, in order to check whether the pll works.

However, I didn't found the code that enables the LDOs in the BSP A23/31
sources, so you must test them to ensure whether the code is needed for
these SoCs.

Regards,
Icenowy
 drivers/clk/sunxi-ng/ccu-sun8i-a33.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/clk/sunxi-ng/ccu-sun8i-a33.c b/drivers/clk/sunxi-ng/ccu-sun8i-a33.c
index 96b40ca..9bd1f78 100644
--- a/drivers/clk/sunxi-ng/ccu-sun8i-a33.c
+++ b/drivers/clk/sunxi-ng/ccu-sun8i-a33.c
@@ -131,7 +131,7 @@ static SUNXI_CCU_NKM_WITH_GATE_LOCK(pll_mipi_clk, "pll-mipi",
 				    8, 4,		/* N */
 				    4, 2,		/* K */
 				    0, 4,		/* M */
-				    BIT(31),		/* gate */
+				    BIT(31) | BIT(23) | BIT(22), /* gate */
 				    BIT(28),		/* lock */
 				    CLK_SET_RATE_UNGATE);
 
-- 
2.10.1

[PATCH] clk: sunxi-ng: enable so-said LDOs for A33 SoC's pll-mipi clock

[Chen-Yu Tsai]

On Fri, Nov 18, 2016 at 12:49 AM, Icenowy Zheng <icenowy@aosc.xyz> wrote:
> In the user manual of A33 SoC, the bit 22 and 23 of pll-mipi control
> register is called "LDO{1,2}_EN", and according to the BSP source code
> from Allwinner [1], the LDOs are enabled during the clock's enabling
> process.
>
> The clock failed to generate output if the two LDOs are not enabled.
>
> Add the two bits to the clock's gate bits, so that the LDOs are enabled
> when the PLL is enabled.
>
> [1] https://github.com/allwinner-zh/linux-3.4-sunxi/blob/master/drivers/clk/sunxi/clk-sun8iw5.c#L429
>
> Fixes: d05c748bd730 ("clk: sunxi-ng: Add A33 CCU support")
>

You don't need the extra line.

> Signed-off-by: Icenowy Zheng <icenowy@aosc.xyz>

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

> ---
> Dear Chen-Yu:
> As you said, the two bits are also present in the CCU of A23 and A31.
> Could you please check whether the PLL works on the two SoCs?
> I remembered you mentioned you failed to make TCON enabled on A23.
> On A31, you may hack the parent of tcon-ch0 to force the tcon clock to
> use pll-mipi as parent, in order to check whether the pll works.
>
> However, I didn't found the code that enables the LDOs in the BSP A23/31
> sources, so you must test them to ensure whether the code is needed for
> these SoCs.

I tested out this for both the A31 and the A23. It fixes issues I've
had with DRM. I'll send patches for them.

ChenYu

> Regards,
> Icenowy
>  drivers/clk/sunxi-ng/ccu-sun8i-a33.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/clk/sunxi-ng/ccu-sun8i-a33.c b/drivers/clk/sunxi-ng/ccu-sun8i-a33.c
> index 96b40ca..9bd1f78 100644
> --- a/drivers/clk/sunxi-ng/ccu-sun8i-a33.c
> +++ b/drivers/clk/sunxi-ng/ccu-sun8i-a33.c
> @@ -131,7 +131,7 @@ static SUNXI_CCU_NKM_WITH_GATE_LOCK(pll_mipi_clk, "pll-mipi",
>                                     8, 4,               /* N */
>                                     4, 2,               /* K */
>                                     0, 4,               /* M */
> -                                   BIT(31),            /* gate */
> +                                   BIT(31) | BIT(23) | BIT(22), /* gate */
>                                     BIT(28),            /* lock */
>                                     CLK_SET_RATE_UNGATE);
>
> --
> 2.10.1
>

[PATCH] clk: sunxi-ng: enable so-said LDOs for A33 SoC's pll-mipi clock

[Icenowy Zheng]

18.11.2016, 00:50, "Icenowy Zheng" <icenowy@aosc.xyz>:
> In the user manual of A33 SoC, the bit 22 and 23 of pll-mipi control
> register is called "LDO{1,2}_EN", and according to the BSP source code
> from Allwinner [1], the LDOs are enabled during the clock's enabling
> process.
>
> The clock failed to generate output if the two LDOs are not enabled.
>
> Add the two bits to the clock's gate bits, so that the LDOs are enabled
> when the PLL is enabled.
>
> [1] https://github.com/allwinner-zh/linux-3.4-sunxi/blob/master/drivers/clk/sunxi/clk-sun8iw5.c#L429
>
> Fixes: d05c748bd730 ("clk: sunxi-ng: Add A33 CCU support")
>
> Signed-off-by: Icenowy Zheng <icenowy@aosc.xyz>

I forgot to mention that this patch should also apply to 4.9.

As A33 support is added, the problem will appear with some LCD panels.

> ---
> Dear Chen-Yu:
> As you said, the two bits are also present in the CCU of A23 and A31.
> Could you please check whether the PLL works on the two SoCs?
> I remembered you mentioned you failed to make TCON enabled on A23.
> On A31, you may hack the parent of tcon-ch0 to force the tcon clock to
> use pll-mipi as parent, in order to check whether the pll works.
>
> However, I didn't found the code that enables the LDOs in the BSP A23/31
> sources, so you must test them to ensure whether the code is needed for
> these SoCs.
>
> Regards,
> Icenowy
> ?drivers/clk/sunxi-ng/ccu-sun8i-a33.c | 2 +-
> ?1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/clk/sunxi-ng/ccu-sun8i-a33.c b/drivers/clk/sunxi-ng/ccu-sun8i-a33.c
> index 96b40ca..9bd1f78 100644
> --- a/drivers/clk/sunxi-ng/ccu-sun8i-a33.c
> +++ b/drivers/clk/sunxi-ng/ccu-sun8i-a33.c
> @@ -131,7 +131,7 @@ static SUNXI_CCU_NKM_WITH_GATE_LOCK(pll_mipi_clk, "pll-mipi",
> ?????????????????????????????????????8, 4, /* N */
> ?????????????????????????????????????4, 2, /* K */
> ?????????????????????????????????????0, 4, /* M */
> - BIT(31), /* gate */
> + BIT(31) | BIT(23) | BIT(22), /* gate */
> ?????????????????????????????????????BIT(28), /* lock */
> ?????????????????????????????????????CLK_SET_RATE_UNGATE);
>
> --
> 2.10.1