Re: [PATCH v1 3/3] pinctrl: pinctrl-aspeed-g6: Add sgpio pinctrl settings

["Andrew Jeffery" <andrew@aj.id.au>]

Hi Steven,

On Mon, 24 May 2021, at 20:43, Steven Lee wrote:
> AST2600 supports 2 SGPIO master interfaces and 2 SGPIO slave interfaces.
> Current pinctrl driver only define the first sgpio master and slave
> interfaces.
> The sencond SGPIO master and slave interfaces should be added in
> pinctrl driver as well.
> 
> Signed-off-by: Steven Lee <steven_lee@aspeedtech.com>
> ---
>  drivers/pinctrl/aspeed/pinctrl-aspeed-g6.c | 24 ++++++++++++++++++----
>  drivers/pinctrl/aspeed/pinmux-aspeed.h     |  9 ++++++++
>  2 files changed, 29 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/pinctrl/aspeed/pinctrl-aspeed-g6.c 
> b/drivers/pinctrl/aspeed/pinctrl-aspeed-g6.c
> index 5c1a109842a7..d0e9ab9d1a9c 100644
> --- a/drivers/pinctrl/aspeed/pinctrl-aspeed-g6.c
> +++ b/drivers/pinctrl/aspeed/pinctrl-aspeed-g6.c
> @@ -46,8 +46,10 @@
>  #define SCU620		0x620 /* Disable GPIO Internal Pull-Down #4 */
>  #define SCU634		0x634 /* Disable GPIO Internal Pull-Down #5 */
>  #define SCU638		0x638 /* Disable GPIO Internal Pull-Down #6 */
> +#define SCU690		0x690 /* Multi-function Pin Control #24 */
>  #define SCU694		0x694 /* Multi-function Pin Control #25 */
>  #define SCU69C		0x69C /* Multi-function Pin Control #27 */
> +#define SCU6D0		0x6D0 /* Multi-function Pin Control #29 */
>  #define SCUC20		0xC20 /* PCIE configuration Setting Control */
>  
>  #define ASPEED_G6_NR_PINS 256
> @@ -81,13 +83,17 @@ FUNC_GROUP_DECL(I2C12, L26, K24);
>  #define K26 4
>  SIG_EXPR_LIST_DECL_SESG(K26, MACLINK1, MACLINK1, SIG_DESC_SET(SCU410, 4));
>  SIG_EXPR_LIST_DECL_SESG(K26, SCL13, I2C13, SIG_DESC_SET(SCU4B0, 4));
> -PIN_DECL_2(K26, GPIOA4, MACLINK1, SCL13);
> +SIG_EXPR_LIST_DECL_SESG(K26, SGPS2CK, SGPS2, SIG_DESC_SET(SCU690, 4));
> +SIG_EXPR_LIST_DECL_SESG(K26, SGPM2CLK, SGPM2, SIG_DESC_SET(SCU6D0, 4));
> +PIN_DECL_4(K26, GPIOA4, SGPM2CLK, SGPS2CK, MACLINK1, SCL13);

Is this the right priority order? Looking at the Multi-Function Pin 
Mapping and Control table, function 1 is MACLINK1,
function 2 is SCL13, function 3 is SGPS2CK, and I assume function 4 
would be SGPM2CLK, except it's not documented in the table in v9 of the 
datasheet (I hope it will be documented?).

If function 1 is the highest priority (which is what all the Aspeed 
pinctrl drivers assume), then this should be:

PIN_DECL_4(K26, GPIOA4, MACLINK1, SCL13, SGPS2CK, SGPM2CLK);

Anyway, one of several things could be at fault here:

1. I've made a wrong assumption about the priority order in how I've 
implemented pinctrl support for Aspeed SoCs

2. The Multi-Function Pin Mapping and Control table is out of date and 
needs to be fixed (which it already does as it doesn't list SGPM2CLK).

3. The patch needs to align with the assumptions of the Aspeed pinctrl 
support.

I don't think it's 1 as I haven't heard of any issues where we are 
getting incorrect behaviour because of pinmux. I don't think it's 2 as 
this patch makes a non-linear change to the ordering. So my hunch is
the issue is 3, that the patch is putting the signals in the wrong order.
In this case, you want the PIN_DECL_4(...) I outlined above.

>  FUNC_GROUP_DECL(MACLINK1, K26);
>  
>  #define L24 5
>  SIG_EXPR_LIST_DECL_SESG(L24, MACLINK2, MACLINK2, SIG_DESC_SET(SCU410, 5));
>  SIG_EXPR_LIST_DECL_SESG(L24, SDA13, I2C13, SIG_DESC_SET(SCU4B0, 5));
> -PIN_DECL_2(L24, GPIOA5, MACLINK2, SDA13);
> +SIG_EXPR_LIST_DECL_SESG(L24, SGPS2LD, SGPS2, SIG_DESC_SET(SCU690, 5));
> +SIG_EXPR_LIST_DECL_SESG(L24, SGPM2LD, SGPM2, SIG_DESC_SET(SCU6D0, 5));
> +PIN_DECL_4(L24, GPIOA5, SGPM2LD, SGPS2LD, MACLINK2, SDA13);

See above.

>  FUNC_GROUP_DECL(MACLINK2, L24);
>  
>  FUNC_GROUP_DECL(I2C13, K26, L24);
> @@ -95,16 +101,22 @@ FUNC_GROUP_DECL(I2C13, K26, L24);
>  #define L23 6
>  SIG_EXPR_LIST_DECL_SESG(L23, MACLINK3, MACLINK3, SIG_DESC_SET(SCU410, 6));
>  SIG_EXPR_LIST_DECL_SESG(L23, SCL14, I2C14, SIG_DESC_SET(SCU4B0, 6));
> -PIN_DECL_2(L23, GPIOA6, MACLINK3, SCL14);
> +SIG_EXPR_LIST_DECL_SESG(L23, SGPS2O, SGPS2, SIG_DESC_SET(SCU690, 6));
> +SIG_EXPR_LIST_DECL_SESG(L23, SGPM2O, SGPM2, SIG_DESC_SET(SCU6D0, 6));
> +PIN_DECL_4(L23, GPIOA6, SGPM2O, SGPS2O, MACLINK3, SCL14);

See above.

>  FUNC_GROUP_DECL(MACLINK3, L23);
>  
>  #define K25 7
>  SIG_EXPR_LIST_DECL_SESG(K25, MACLINK4, MACLINK4, SIG_DESC_SET(SCU410, 7));
>  SIG_EXPR_LIST_DECL_SESG(K25, SDA14, I2C14, SIG_DESC_SET(SCU4B0, 7));
> -PIN_DECL_2(K25, GPIOA7, MACLINK4, SDA14);
> +SIG_EXPR_LIST_DECL_SESG(K25, SGPS2I, SGPS2, SIG_DESC_SET(SCU690, 7));
> +SIG_EXPR_LIST_DECL_SESG(K25, SGPM2I, SGPM2, SIG_DESC_SET(SCU6D0, 7));
> +PIN_DECL_4(K25, GPIOA7, SGPM2I, SGPS2I, MACLINK4, SDA14);

See above.

>  FUNC_GROUP_DECL(MACLINK4, K25);
>  
>  FUNC_GROUP_DECL(I2C14, L23, K25);
> +FUNC_GROUP_DECL(SGPM2, K26, L24, L23, K25);
> +FUNC_GROUP_DECL(SGPS2, K26, L24, L23, K25);
>  
>  #define J26 8
>  SIG_EXPR_LIST_DECL_SESG(J26, SALT1, SALT1, SIG_DESC_SET(SCU410, 8));
> @@ -2060,7 +2072,9 @@ static const struct aspeed_pin_group 
> aspeed_g6_groups[] = {
>  	ASPEED_PINCTRL_GROUP(EMMCG4),
>  	ASPEED_PINCTRL_GROUP(EMMCG8),
>  	ASPEED_PINCTRL_GROUP(SGPM1),
> +	ASPEED_PINCTRL_GROUP(SGPM2),
>  	ASPEED_PINCTRL_GROUP(SGPS1),
> +	ASPEED_PINCTRL_GROUP(SGPS2),
>  	ASPEED_PINCTRL_GROUP(SIOONCTRL),
>  	ASPEED_PINCTRL_GROUP(SIOPBI),
>  	ASPEED_PINCTRL_GROUP(SIOPBO),
> @@ -2276,7 +2290,9 @@ static const struct aspeed_pin_function 
> aspeed_g6_functions[] = {
>  	ASPEED_PINCTRL_FUNC(SD1),
>  	ASPEED_PINCTRL_FUNC(SD2),
>  	ASPEED_PINCTRL_FUNC(SGPM1),
> +	ASPEED_PINCTRL_FUNC(SGPM2),
>  	ASPEED_PINCTRL_FUNC(SGPS1),
> +	ASPEED_PINCTRL_FUNC(SGPS2),
>  	ASPEED_PINCTRL_FUNC(SIOONCTRL),
>  	ASPEED_PINCTRL_FUNC(SIOPBI),
>  	ASPEED_PINCTRL_FUNC(SIOPBO),
> diff --git a/drivers/pinctrl/aspeed/pinmux-aspeed.h 
> b/drivers/pinctrl/aspeed/pinmux-aspeed.h
> index dba5875ff276..125df796af36 100644
> --- a/drivers/pinctrl/aspeed/pinmux-aspeed.h
> +++ b/drivers/pinctrl/aspeed/pinmux-aspeed.h
> @@ -730,6 +730,15 @@ struct aspeed_pin_desc {
>  			SIG_EXPR_LIST_PTR(pin, low), \
>  			SIG_EXPR_LIST_PTR(pin, other))
>  
> +#define PIN_DECL_4(pin, other, high, medium, low1, low2) \

Bit of a nit pick, but we might as well drop identifying the priorities 
as high, medium and low given we now have low1 and low2. Maybe 
something like this:

#define PIN_DECL_4(pin, other, prio1, prio2, prio3, prio4)

Cheers,

Andrew