[U-Boot] [PATCH v2 10/12] jetson-tk1: Add PSCI configuration options and reserve secure code

Jan Kiszka
2015-02-18T07:39:43Z

On 2015-02-17 22:05, Stephen Warren wrote:
> On 02/16/2015 05:54 AM, Jan Kiszka wrote:
>> The secure world code is relocated to the MB just below the top of 4G, we
>> reserve it in the FDT (by setting CONFIG_ARMV7_SECURE_RESERVE_SIZE)
>> but it is
>> not protected in h/w. See next patch.
>
>> diff --git a/include/configs/jetson-tk1.h b/include/configs/jetson-tk1.h
>
>> +#define CONFIG_ARMV7_PSCI 1
>> +/* Reserve top 1M for secure RAM */
>> +#define CONFIG_ARMV7_SECURE_BASE 0xfff00000
>
> Can that not be dynamic? What if the system only has 1GB RAM not 2GB.
> It's true that all shipped/public versions of this board do have 2GB
> AFAIK, but we have had internal versions with different amounts of RAM,
> and I don't think there's anything else in Tegra U-Boots that hard-codes
> RAM sizes.

I tested and checked the PSCI code again, and it turned out to be not
position independent yet (vector tables, functions pointers). Everything
can be fixed, but I wonder if this shouldn't be done on top, when we
have a concrete need.

Locating the monitor may involve more factors on different SoCs and
boards. So a general solution may be more complicated, even when dynamic
relocation itself is solved.

Jan

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