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| author | Juan Castillo <juan.castillo@arm.com> | 2015-11-06 16:02:32 +0000 |
|---|---|---|
| committer | Juan Castillo <juan.castillo@arm.com> | 2016-01-20 09:49:45 +0000 |
| commit | 0e5dcdd254ef24d9d7ff9587e65dcc34d21c190e (patch) | |
| tree | 60efc43b05d89e4152d3bf1899921d8c3c7de369 /docs | |
| parent | f9410b47c3ea36c9c231760a85efbbb7d6e575a7 (diff) | |
ARM plat: add build option to unlock access to non-secure timer
Currently, Trusted Firmware on ARM platforms unlocks access to the
timer frame registers that will be used by the Non-Secure world. This
unlock operation should be done by the Non-Secure software itself,
instead of relying on secure firmware settings.
This patch adds a new ARM specific build option 'ARM_CONFIG_CNTACR'
to unlock access to the timer frame by setting the corresponding
bits in the CNTACR<N> register. The frame id <N> is defined by
'PLAT_ARM_NSTIMER_FRAME_ID'. Default value is true (unlock timer
access).
Documentation updated accordingly.
Fixes ARM-software/tf-issues#170
Change-Id: Id9d606efd781e43bc581868cd2e5f9c8905bdbf6
Diffstat (limited to 'docs')
| -rw-r--r-- | docs/user-guide.md | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/docs/user-guide.md b/docs/user-guide.md index 3337f88d..894d69bd 100644 --- a/docs/user-guide.md +++ b/docs/user-guide.md @@ -456,6 +456,12 @@ map is explained in the [Firmware Design]. Trusted Watchdog may be disabled at build time for testing or development purposes. +* `ARM_CONFIG_CNTACR`: boolean option to unlock access to the CNTBase<N> + frame registers by setting the CNTCTLBase.CNTACR<N> register bits. The + frame number <N> is defined by 'PLAT_ARM_NSTIMER_FRAME_ID', which should + match the frame used by the Non-Secure image (normally the Linux kernel). + Default is true (access to the frame is allowed). + #### ARM CSS platform specific build options * `CSS_DETECT_PRE_1_7_0_SCP`: Boolean flag to detect SCP version |