[U-Boot] [PATCH u-boot 3/5] aspeed: Added function to calculate APB Clock frequency.

[Simon Glass]

Hi Maxim,

On 22 November 2016 at 16:56,  <maxims at google.com> wrote:
> From: Maxim Sloyko <maxims at google.com>
>

For the subject, 'Add' rather than 'Added' (we use present tense)

> This is needed by I2C driver.
>
> Signed-off-by: Maxim Sloyko <maxims at google.com>
> ---
>  arch/arm/include/asm/arch-aspeed/ast_scu.h |  1 +
>  arch/arm/mach-aspeed/ast-scu.c             | 11 +++++++++++
>  2 files changed, 12 insertions(+)
>
> diff --git a/arch/arm/include/asm/arch-aspeed/ast_scu.h b/arch/arm/include/asm/arch-aspeed/ast_scu.h
> index d248416..eb5aaa2 100644
> --- a/arch/arm/include/asm/arch-aspeed/ast_scu.h
> +++ b/arch/arm/include/asm/arch-aspeed/ast_scu.h
> @@ -38,6 +38,7 @@ extern void ast_scu_get_who_init_dram(void);
>  extern u32 ast_get_clk_source(void);
>  extern u32 ast_get_h_pll_clk(void);
>  extern u32 ast_get_ahbclk(void);
> +extern u32 ast_get_apbclk(void);

Please add a comment as to what this does and what it returns.

>
>  extern u32 ast_scu_get_vga_memsize(void);
>
> diff --git a/arch/arm/mach-aspeed/ast-scu.c b/arch/arm/mach-aspeed/ast-scu.c
> index 280c421..e00dbe2 100644
> --- a/arch/arm/mach-aspeed/ast-scu.c
> +++ b/arch/arm/mach-aspeed/ast-scu.c
> @@ -318,6 +318,17 @@ u32 ast_get_ahbclk(void)
>
>  #endif /* AST_SOC_G5 */
>
> +u32 ast_get_apbclk(void)
> +{
> +       u32 h_pll = ast_get_h_pll_clk();

Can this be ulong, or is there a reason it has to be exactly 32 bits?

blank line here (between declarations and code)

> +       /* The formula for converting the bit pattern to divisor is

/*
 * The formula...
 * ...
 */

> +        * (4 + 4 * DIV), according to datasheet
> +        */
> +       u32 apb_div = 4 + 4 * SCU_GET_PCLK_DIV(ast_scu_read(AST_SCU_CLK_SEL));
> +       return h_pll / apb_div;
> +}
> +
> +
>  void ast_scu_show_system_info(void)
>  {
>
> --
> 2.8.0.rc3.226.g39d4020
>

Regards,
Simon