[U-Boot] [PATCHv5 3/4] ARM: tegra124: Add an option to disable CoreSight

[Julian Scheel]

On 06.09.16 18:54, Stephen Warren wrote:
> On 09/05/2016 07:29 AM, Julian Scheel wrote:
>> From: Alban Bedel <alban.bedel at avionic-design.de>
>>
>> When running on a SoC with a secure bootloader CoreSight isn't
>> allowed, so add an option to disable the CoreSight init.
>
>> diff --git a/arch/arm/mach-tegra/Kconfig b/arch/arm/mach-tegra/Kconfig
>
>> +config ENABLE_CORESIGHT
>> +    bool "Enable CoreSight"
>> +    default y
>
> Why "default y"? This changes behaviour on all our open development
> boards. "default y" should be dropped, and the option should be added to
> the defconfig for your board, or selected by the board's Kconfig option.

It's default yes, because the current codepath has it enabled. This 
patch actually makes it possible to disable CoreSight by setting this 
option to "n". Previously the code in clock_enable_coresight was run 
unconditionally.

>> diff --git a/arch/arm/mach-tegra/cpu.c b/arch/arm/mach-tegra/cpu.c
>
>>  void clock_enable_coresight(int enable)
>>  {
>> +#if defined(CONFIG_ENABLE_CORESIGHT)
>>      u32 rst, src = 2;
>>
>>      debug("%s entry\n", __func__);
>> @@ -402,6 +403,7 @@ void clock_enable_coresight(int enable)
>>              writel(rst, CSITE_CPU_DBG3_LAR);
>>          }
>>      }
>> +#endif
>>  }
>
> It might be better to ifdef out the call-site. Otherwise, someone
> reading that code won't have any idea that the function actually does
> nothing.

Ok, I can change that.