summaryrefslogtreecommitdiffstats
path: root/Documentation/arm64
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2014-04-08 21:06:03 +0200
committerLinus Torvalds <torvalds@linux-foundation.org>2014-04-08 21:06:03 +0200
commite4f30545a23b6e22fb347a1ad034ce1aa280209c (patch)
tree415db60ace3ab89fe150bca797c690ddaf021432 /Documentation/arm64
parentMerge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s39... (diff)
parentarm64: Fix DMA range invalidation for cache line unaligned buffers (diff)
downloadlinux-e4f30545a23b6e22fb347a1ad034ce1aa280209c.tar.xz
linux-e4f30545a23b6e22fb347a1ad034ce1aa280209c.zip
Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull second set of arm64 updates from Catalin Marinas: "A second pull request for this merging window, mainly with fixes and docs clarification: - Documentation clarification on CPU topology and booting requirements - Additional cache flushing during boot (needed in the presence of external caches or under virtualisation) - DMA range invalidation fix for non cache line aligned buffers - Build failure fix with !COMPAT - Kconfig update for STRICT_DEVMEM" * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: arm64: Fix DMA range invalidation for cache line unaligned buffers arm64: Add missing Kconfig for CONFIG_STRICT_DEVMEM arm64: fix !CONFIG_COMPAT build failures Revert "arm64: virt: ensure visibility of __boot_cpu_mode" arm64: Relax the kernel cache requirements for boot arm64: Update the TCR_EL1 translation granule definitions for 16K pages ARM: topology: Make it clear that all CPUs need to be described
Diffstat (limited to 'Documentation/arm64')
-rw-r--r--Documentation/arm64/booting.txt10
1 files changed, 8 insertions, 2 deletions
diff --git a/Documentation/arm64/booting.txt b/Documentation/arm64/booting.txt
index a9691cc48fe3..beb754e87c65 100644
--- a/Documentation/arm64/booting.txt
+++ b/Documentation/arm64/booting.txt
@@ -111,8 +111,14 @@ Before jumping into the kernel, the following conditions must be met:
- Caches, MMUs
The MMU must be off.
Instruction cache may be on or off.
- Data cache must be off and invalidated.
- External caches (if present) must be configured and disabled.
+ The address range corresponding to the loaded kernel image must be
+ cleaned to the PoC. In the presence of a system cache or other
+ coherent masters with caches enabled, this will typically require
+ cache maintenance by VA rather than set/way operations.
+ System caches which respect the architected cache maintenance by VA
+ operations must be configured and may be enabled.
+ System caches which do not respect architected cache maintenance by VA
+ operations (not recommended) must be configured and disabled.
- Architected timers
CNTFRQ must be programmed with the timer frequency and CNTVOFF must