[U-Boot] [PATCH v2 11/12] tegra124: Reserve secure RAM using MC_SECURITY_CFG{0, 1}_0

Jan Kiszka
2015-02-18T07:24:57Z

On 2015-02-17 22:06, Stephen Warren wrote:
> On 02/16/2015 05:54 AM, Jan Kiszka wrote:
>> From: Ian Campbell <ijc@hellion.org.uk>
>>
>> These registers can be used to prevent non-secure world from accessing a
>> megabyte aligned region of RAM, use them to protect the u-boot secure
>> monitor
>> code.
>>
>> At first I tried to do this from s_init(), however this inexplicably
>> causes
>> u-boot's networking (e.g. DHCP) to fail, while networking under Linux
>> was fine.
>>
>> So instead I have added a new weak arch function protect_secure_section()
>> called from relocate_secure_section() and reserved the region there.
>> This is
>> better overall since it defers the reservation until after the sec vs.
>> non-sec
>> decision (which can be influenced by an envvar) has been made when
>> booting the
>> os.
>
>> diff --git a/arch/arm/cpu/tegra-common/ap.c
>> b/arch/arm/cpu/tegra-common/ap.c
>
>> +void protect_secure_section(void)
>
>> + writel(CONFIG_ARMV7_SECURE_BASE, &mc->mc_security_cfg0);
>> + writel(CONFIG_ARMV7_SECURE_RESERVE_SIZE>>20, &mc->mc_security_cfg1);
>
> Spaces around the >> ?

Fixed for v3.

Thanks,
Jan

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