Good Afternoon,

I have tested these patches on the Ouya T3 device.
They work great to enable the L2 cache controller, however they do not 
respect explicitly disabling the L2 cache controller via the kernel 
config nor device tree.

With CONFIG_CACHE_L2X0 disabled, but CONFIG_TRUSTED_FOUNDATIONS enabled, 
the L2 cache controller is silently enabled and allows all four cores to 
boot.

One must also disable CONFIG_TRUSTED_FOUNDATIONS to stop the L2 cache 
controller from spinning up.

Tested-by: Peter Geis <redacted>

On 06/19/2018 07:00 AM, Dmitry Osipenko wrote:

Hello,

This series of patches brings initial support of Trusted Foundations to
Tegra30, that is to the consumer-grade Tegra30 devices which do not allow
to easily replace the proprietary bootloader. Support is initial because
this series implements only a proper CPU boot-up (main + secondary cores)
and a basic L2 cache maintenance that is done using the TF firmware.
Suspend-resume support is missing yet as I couldn't get it to work
(CPU hangs on resume from suspend after awhile and seems that is related
to inappropriately done cache maintenance during of suspend-resume using
the firmware), it is work-in-progress for now.

This patchset is partially based on the work done by Micha? Miros?aw [0].

[0] https://www.spinics.net/lists/linux-tegra/msg30368.html

Changelog:

v2:
	- The "Don't apply CPU erratas in insecure mode" patch got some
	  cleanup, in particular resolved the messiness in
	  __tegra_cpu_reset_handler_data.

	- Added a comment to tf_cache_write_sec(), justifying the warning
	  message.

Dmitry Osipenko (5):
   ARM: trusted_foundations: Implement L2 cache initialization callback
   ARM: trusted_foundations: Provide information about whether firmware
     is registered
   ARM: tegra: Setup L2 cache using Trusted Foundations firmware
   ARM: tegra: Don't apply CPU erratas in insecure mode
   ARM: tegra: Always boot CPU in ARM-mode

  arch/arm/firmware/trusted_foundations.c    | 32 ++++++++++++++++++++++
  arch/arm/include/asm/trusted_foundations.h |  7 +++++
  arch/arm/mach-tegra/reset-handler.S        | 25 +++++++++--------
  arch/arm/mach-tegra/reset.c                |  5 +++-
  arch/arm/mach-tegra/reset.h                |  9 ++++--
  arch/arm/mach-tegra/sleep-tegra20.S        |  4 +++
  arch/arm/mach-tegra/tegra.c                | 15 ++++++++++
  7 files changed, 82 insertions(+), 15 deletions(-)