[PATCH v1 10/15] aspeed: Add P-Bus clock in ast2500 clock driver

[Simon Glass]

On 17 April 2017 at 13:00, Maxim Sloyko <maxims at google.com> wrote:
> Add P-Bus Clock support to ast2500 clock driver.
> This is the clock used by I2C devices.
>
> Signed-off-by: Maxim Sloyko <maxims at google.com>
> ---
>
> Changes in v1: None
>
>  arch/arm/include/asm/arch-aspeed/scu_ast2500.h |  3 ++-
>  drivers/clk/aspeed/clk_ast2500.c               | 11 +++++++++++
>  2 files changed, 13 insertions(+), 1 deletion(-)
>

Reviewed-by: Simon Glass <sjg at chromium.org>

> diff --git a/arch/arm/include/asm/arch-aspeed/scu_ast2500.h b/arch/arm/include/asm/arch-aspeed/scu_ast2500.h
> index 1cdd3b9198..319d75e05c 100644
> --- a/arch/arm/include/asm/arch-aspeed/scu_ast2500.h
> +++ b/arch/arm/include/asm/arch-aspeed/scu_ast2500.h
> @@ -21,7 +21,8 @@
>  #define SCU_MPLL_NUM_MASK              0xff
>  #define SCU_MPLL_POST_SHIFT            13
>  #define SCU_MPLL_POST_MASK             0x3f

I think it works better in general if the mask is defined as 0x3f <<
SCU_MPLL_POST_SHIFT. Something to think about as a possible clean-up.

> -
> +#define SCU_PCLK_DIV_SHIFT             23
> +#define SCU_PCLK_DIV_MASK              7
>  #define SCU_HPLL_DENUM_SHIFT           0
>  #define SCU_HPLL_DENUM_MASK            0x1f
>  #define SCU_HPLL_NUM_SHIFT             5
> diff --git a/drivers/clk/aspeed/clk_ast2500.c b/drivers/clk/aspeed/clk_ast2500.c
> index 504731271c..9e4c66ea85 100644
> --- a/drivers/clk/aspeed/clk_ast2500.c
> +++ b/drivers/clk/aspeed/clk_ast2500.c
> @@ -110,6 +110,17 @@ static ulong ast2500_clk_get_rate(struct clk *clk)
>                 rate = ast2500_get_mpll_rate(clkin,
>                                              readl(&priv->scu->m_pll_param));
>                 break;
> +       case BCLK_PCLK:
> +               {
> +                       ulong apb_div = 4 + 4 * ((readl(&priv->scu->clk_sel1)
> +                                                 >> SCU_PCLK_DIV_SHIFT) &
> +                                                SCU_PCLK_DIV_MASK);
> +                       rate = ast2500_get_hpll_rate(clkin,
> +                                                    readl(&priv->scu->
> +                                                          h_pll_param));
> +                       rate = rate / apb_div;
> +               }
> +               break;
>         case PCLK_UART1:
>                 rate = ast2500_get_uart_clk_rate(priv->scu, 1);
>                 break;
> --
> 2.12.2.762.g0e3151a226-goog
>

Regards,
Simon