[U-Boot] [PATCH v3 4/9] pico-imx7d: Correct uart clock root

[Jun Nie]

Peng Fan <peng.fan at nxp.com> 于2019年4月24日周三 下午1:15写道：
>
>
> > Subject: [PATCH v3 4/9] pico-imx7d: Correct uart clock root
> >
> > Correct uart clock root ID. Incorrect ID may result the clock is gated because
> > rate value 0 is returned in
> > imx_get_uartclk()
>
> Yes. hardcoding to UART1_ROOT_CLK in imx_get_uartclk is not good.
> But actually init_clk_uart configures all the uart with same root clk,
> so it should work as expected.

Right, but init_clk_uart is not called in SKIP_LOWLEVEL_INIT case.
#ifndef CONFIG_SKIP_LOWLEVEL_INIT
cpu_init_crit() ->  lowlevel_init() -> s_init() -> clock_init() ->
init_clk_uart()
#endif

>
> Regards,
> Peng.
>
> >
> > Signed-off-by: Jun Nie <jun.nie at linaro.org>
> > ---
> >  arch/arm/include/asm/arch-mx7/clock.h | 18 ++++++++++++++++++
> >  arch/arm/mach-imx/Kconfig             |  7 +++++++
> >  arch/arm/mach-imx/mx7/clock.c         |  2 +-
> >  3 files changed, 26 insertions(+), 1 deletion(-)
> >
> > diff --git a/arch/arm/include/asm/arch-mx7/clock.h
> > b/arch/arm/include/asm/arch-mx7/clock.h
> > index f56564e..dc91111 100644
> > --- a/arch/arm/include/asm/arch-mx7/clock.h
> > +++ b/arch/arm/include/asm/arch-mx7/clock.h
> > @@ -175,6 +175,24 @@ enum clk_root_index {
> >       CLK_ROOT_MAX,
> >  };
> >
> > +#if (CONFIG_IMX_CONSOLE_UART_ID == 1)
> > +#define UART_CLK_ROOT UART1_CLK_ROOT
> > +#elif (CONFIG_IMX_CONSOLE_UART_ID == 2) #define UART_CLK_ROOT
> > +UART2_CLK_ROOT #elif (CONFIG_IMX_CONSOLE_UART_ID == 3) #define
> > +UART_CLK_ROOT UART3_CLK_ROOT #elif
> > (CONFIG_IMX_CONSOLE_UART_ID == 4)
> > +#define UART_CLK_ROOT UART4_CLK_ROOT #elif
> > (CONFIG_IMX_CONSOLE_UART_ID
> > +== 5) #define UART_CLK_ROOT UART5_CLK_ROOT #elif
> > +(CONFIG_IMX_CONSOLE_UART_ID == 6) #define UART_CLK_ROOT
> > UART6_CLK_ROOT
> > +#elif (CONFIG_IMX_CONSOLE_UART_ID == 7) #define UART_CLK_ROOT
> > +UART7_CLK_ROOT #else #error "Invalid IMX UART ID for serial console is
> > +defined"
> > +#endif
> > +
> >  struct clk_root_setting {
> >       enum clk_root_index root;
> >       u32 setting;
> > diff --git a/arch/arm/mach-imx/Kconfig b/arch/arm/mach-imx/Kconfig index
> > ec09ef2..7c5db30 100644
> > --- a/arch/arm/mach-imx/Kconfig
> > +++ b/arch/arm/mach-imx/Kconfig
> > @@ -27,6 +27,13 @@ config IMX_BOOTAUX
> >       help
> >         bootaux [addr] to boot auxiliary core.
> >
> > +config IMX_CONSOLE_UART_ID
> > +     int "UART ID for console"
> > +     default 1
> > +     depends on ARCH_MX7
> > +     help
> > +       Specify the UART ID that's for serial console.
> > +
> >  config USE_IMXIMG_PLUGIN
> >       bool "Use imximage plugin code"
> >       depends on ARCH_MX7 || ARCH_MX6
> > diff --git a/arch/arm/mach-imx/mx7/clock.c
> > b/arch/arm/mach-imx/mx7/clock.c index 8cda71c..e364b16 100644
> > --- a/arch/arm/mach-imx/mx7/clock.c
> > +++ b/arch/arm/mach-imx/mx7/clock.c
> > @@ -53,7 +53,7 @@ static u32 get_ipg_clk(void)
> >
> >  u32 imx_get_uartclk(void)
> >  {
> > -     return get_root_clk(UART1_CLK_ROOT);
> > +     return get_root_clk(UART_CLK_ROOT);
> >  }
> >
> >  u32 imx_get_fecclk(void)
> > --
> > 2.7.4
>