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2 commits

Author SHA1 Message Date
Stephen Warren
73c38934da ARM: tegra: support running in non-secure mode
When the CPU is in non-secure (NS) mode (when running U-Boot under a
secure monitor), certain actions cannot be taken, since they would need
to write to secure-only registers. One example is configuring the ARM
architectural timer's CNTFRQ register.

We could support this in one of two ways:
1) Compile twice, once for secure mode (in which case anything goes) and
   once for non-secure mode (in which case certain actions are disabled).
   This complicates things, since everyone needs to keep track of
   different U-Boot binaries for different situations.
2) Detect NS mode at run-time, and optionally skip any impossible actions.
   This has the advantage of a single U-Boot binary working in all cases.

(2) is not possible on ARM in general, since there's no architectural way
to detect secure-vs-non-secure. However, there is a Tegra-specific way to
detect this.

This patches uses that feature to detect secure vs. NS mode on Tegra, and
uses that to:

* Skip the ARM arch timer initialization.

* Set/clear an environment variable so that boot scripts can take
  different action depending on which mode the CPU is in. This might be
  something like:
  if CPU is secure:
    load secure monitor code into RAM.
    boot secure monitor.
    secure monitor will restart (a new copy of) U-Boot in NS mode.
  else:
    execute normal boot process

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Tom Warren <twarren@nvidia.com>
2015-03-04 10:08:57 -07:00
Masahiro Yamada
09f455dca7 ARM: tegra: collect SoC sources into mach-tegra
This commit moves files as follows:

 arch/arm/cpu/arm720t/tegra20/*      -> arch/arm/mach-tegra/tegra20/*
 arch/arm/cpu/arm720t/tegra30/*      -> arch/arm/mach-tegra/tegra30/*
 arch/arm/cpu/arm720t/tegra114/*     -> arch/arm/mach-tegra/tegra114/*
 arch/arm/cpu/arm720t/tegra124*      -> arch/arm/mach-tegra/tegra124/*
 arch/arm/cpu/arm720t/tegra-common/* -> arch/arm/mach-tegra/*
 arch/arm/cpu/armv7/tegra20/*        -> arch/arm/mach-tegra/tegra20/*
 arch/arm/cpu/armv7/tegra30/*        -> arch/arm/mach-tegra/tegra30/*
 arch/arm/cpu/armv7/tegra114/*       -> arch/arm/mach-tegra/tegra114/*
 arch/arm/cpu/armv7/tegra124/*       -> arch/arm/mach-tegra/tegra124/*
 arch/arm/cpu/armv7/tegra-common/*   -> arch/arm/mach-tegra/*
 arch/arm/cpu/tegra20-common/*       -> arch/arm/mach-tegra/tegra20/*
 arch/arm/cpu/tegra30-common/*       -> arch/arm/mach-tegra/tegra30/*
 arch/arm/cpu/tegra114-common/*      -> arch/arm/mach-tegra/tegra114/*
 arch/arm/cpu/tegra124-common/*      -> arch/arm/mach-tegra/tegra124/*
 arch/arm/cpu/tegra-common/*         -> arch/arm/mach-tegra/*

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Tested-by: Simon Glass <sjg@chromium.org> [ on nyan-big ]
Cc: Stephen Warren <swarren@nvidia.com>
Cc: Tom Warren <twarren@nvidia.com>
2015-02-21 08:23:51 -05:00
Renamed from arch/arm/cpu/tegra-common/clock.c (Browse further)