[U-Boot] [PATCH] sunxi: set PIO voltage to hardware-detected value on startup on H6

[Icenowy Zheng]

在 2019-04-24三的 13:44 +0800，Icenowy Zheng写道：
> The Allwinner H6 SoC has a register to set the PIO banks' voltage.
> When
> it mismatches the real voltage supplied to the VCC to the PIO supply,
> the PIO will work improperly.
> 
> The PIO controller also has a register that contains the status of
> each
> VCC rail of the PIO supplies, and it has the same definition with the
> configuration register. so we can just copy the content of this
> register
> to the configuration register at startup, to ensure the configuration
> is
> correct at startup stage.
> 
> Signed-off-by: Icenowy Zheng <icenowy at aosc.io>
> ---
>  arch/arm/include/asm/arch-sunxi/gpio.h | 3 +++
>  arch/arm/mach-sunxi/board.c            | 9 +++++++++
>  2 files changed, 12 insertions(+)
> 
> diff --git a/arch/arm/include/asm/arch-sunxi/gpio.h
> b/arch/arm/include/asm/arch-sunxi/gpio.h
> index 40a3f845d0..a646ea6a3c 100644
> --- a/arch/arm/include/asm/arch-sunxi/gpio.h
> +++ b/arch/arm/include/asm/arch-sunxi/gpio.h
> @@ -73,6 +73,9 @@ struct sunxi_gpio_reg {
>  	struct sunxi_gpio_int gpio_int;
>  };
>  
> +#define SUN50I_H6_GPIO_POW_MOD_SEL	0x340
> +#define SUN50I_H6_GPIO_POW_MOD_VAL	0x348
> +
>  #define BANK_TO_GPIO(bank)	(((bank) < SUNXI_GPIO_L) ? \
>  	&((struct sunxi_gpio_reg *)SUNXI_PIO_BASE)->gpio_bank[bank] : \
>  	&((struct sunxi_gpio_reg *)SUNXI_R_PIO_BASE)->gpio_bank[(bank)
> - SUNXI_GPIO_L])
> diff --git a/arch/arm/mach-sunxi/board.c b/arch/arm/mach-
> sunxi/board.c
> index c6dd7b8e54..bd3b5d8303 100644
> --- a/arch/arm/mach-sunxi/board.c
> +++ b/arch/arm/mach-sunxi/board.c
> @@ -65,6 +65,7 @@ struct mm_region *mem_map = sunxi_mem_map;
>  
>  static int gpio_init(void)
>  {
> +	__maybe__unused uint val;

Sorry for the extra _ here. Should be __maybe_unused.

>  #if CONFIG_CONS_INDEX == 1 && defined(CONFIG_UART0_PORT_F)
>  #if defined(CONFIG_MACH_SUN4I) || \
>      defined(CONFIG_MACH_SUN7I) || \
> @@ -139,6 +140,14 @@ static int gpio_init(void)
>  #error Unsupported console port number. Please fix pin mux settings
> in board.c
>  #endif
>  
> +#ifdef CONFIG_MACH_SUN50I_H6
> +	/* Update PIO power bias configuration by copy hardware
> detected value */
> +	val = readl(SUNXI_PIO_BASE + SUN50I_H6_GPIO_POW_MOD_VAL);
> +	writel(val, SUNXI_PIO_BASE + SUN50I_H6_GPIO_POW_MOD_SEL);
> +	val = readl(SUNXI_R_PIO_BASE + SUN50I_H6_GPIO_POW_MOD_VAL);
> +	writel(val, SUNXI_R_PIO_BASE + SUN50I_H6_GPIO_POW_MOD_SEL);
> +#endif
> +
>  	return 0;
>  }
>