[U-Boot] [PATCH 4/6] imx8qm: fix cpu frequency reporting

Max Krummenacher max.krummenacher at toradex.com
Wed May 1 14:18:33 UTC 2019


See review comment below.

With the issue resolved:
Reviewed-by: Max Krummenacher <max.krummenacher at toradex.com>

On Tue, 2019-04-30 at 12:06 +0200, Marcel Ziswiler wrote:
> CPU frequency reporting failed with the following error message being
> printed:
> 
> sc_pm_get_clock_rate: resource:507 clk:2: res:3
> Could not read CPU frequency: -22
> CPU:   NXP i.MX8QM RevB A53 at 0 MHz
> 
> Fix this by differentiating between the A35 as found on the i.MX 8QXP
> and the A53 as found on the i.MX 8QM SoCs.
> 
> Signed-off-by: Marcel Ziswiler <marcel.ziswiler at toradex.com>
> 
> ---
> 
>  arch/arm/mach-imx/imx8/cpu.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/arch/arm/mach-imx/imx8/cpu.c b/arch/arm/mach-imx/imx8/cpu.c
> index 12716e7e9e..0d01e3fc3b 100644
> --- a/arch/arm/mach-imx/imx8/cpu.c
> +++ b/arch/arm/mach-imx/imx8/cpu.c
> @@ -654,8 +654,9 @@ static ulong imx8_get_cpu_rate(void)
>  {
>  	ulong rate;
>  	int ret;
> +	int type = is_cortex_a35() ? SC_R_A35 : SC_R_A53;

The related get_core_name() below foresees that the code could run on
a cortex_a72. So we should here also test with is_cortex_a72 and then
use SC_R_A72 to avoid a follow-up patch for a future i.MX8 SKU or changed
configuration.

Regards,
Max

>  
> -	ret = sc_pm_get_clock_rate(-1, SC_R_A35, SC_PM_CLK_CPU,
> +	ret = sc_pm_get_clock_rate(-1, type, SC_PM_CLK_CPU,
>  				   (sc_pm_clock_rate_t *)&rate);
>  	if (ret) {
>  		printf("Could not read CPU frequency: %d\n", ret);



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