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authorWill Deacon <will@kernel.org>2025-01-17 13:52:23 +0000
committerWill Deacon <will@kernel.org>2025-01-17 13:52:23 +0000
commite190227be427c3de93de738374e6aa1865bfdc1c (patch)
tree234b2becb7d7b8a69e94bfb8c1e60f0151bc82e1
parent763d584c5bb21c120f3e05ddc0fa4f64f6b12a9a (diff)
parentfd10f08cb57b891a9bc7cef4ffb26772d91bebf5 (diff)
Merge branch 'for-next/docs' into for-next/core
* for-next/docs: Documentation: arm64: Remove stale and redundant virtual memory diagrams docs: arm64: Document EL3 requirements for FEAT_PMUv3 docs: arm64: Document EL3 requirements for cpu debug architecture
-rw-r--r--Documentation/arch/arm64/booting.rst12
-rw-r--r--Documentation/arch/arm64/memory.rst65
2 files changed, 12 insertions, 65 deletions
diff --git a/Documentation/arch/arm64/booting.rst b/Documentation/arch/arm64/booting.rst
index 3278fb4bf219d..cad6fdc96b98b 100644
--- a/Documentation/arch/arm64/booting.rst
+++ b/Documentation/arch/arm64/booting.rst
@@ -449,6 +449,18 @@ Before jumping into the kernel, the following conditions must be met:
- HFGWTR_EL2.nGCS_EL0 (bit 52) must be initialised to 0b1.
+ - For CPUs with debug architecture i.e FEAT_Debugv8pN (all versions):
+
+ - If EL3 is present:
+
+ - MDCR_EL3.TDA (bit 9) must be initialized to 0b0
+
+ - For CPUs with FEAT_PMUv3:
+
+ - If EL3 is present:
+
+ - MDCR_EL3.TPM (bit 6) must be initialized to 0b0
+
The requirements described above for CPU mode, caches, MMUs, architected
timers, coherency and system registers apply to all CPUs. All CPUs must
enter the kernel in the same exception level. Where the values documented
diff --git a/Documentation/arch/arm64/memory.rst b/Documentation/arch/arm64/memory.rst
index 8a658984b8bb6..678fbb418c3ad 100644
--- a/Documentation/arch/arm64/memory.rst
+++ b/Documentation/arch/arm64/memory.rst
@@ -23,71 +23,6 @@ swapper_pg_dir contains only kernel (global) mappings while the user pgd
contains only user (non-global) mappings. The swapper_pg_dir address is
written to TTBR1 and never written to TTBR0.
-
-AArch64 Linux memory layout with 4KB pages + 4 levels (48-bit)::
-
- Start End Size Use
- -----------------------------------------------------------------------
- 0000000000000000 0000ffffffffffff 256TB user
- ffff000000000000 ffff7fffffffffff 128TB kernel logical memory map
- [ffff600000000000 ffff7fffffffffff] 32TB [kasan shadow region]
- ffff800000000000 ffff80007fffffff 2GB modules
- ffff800080000000 fffffbffefffffff 124TB vmalloc
- fffffbfff0000000 fffffbfffdffffff 224MB fixed mappings (top down)
- fffffbfffe000000 fffffbfffe7fffff 8MB [guard region]
- fffffbfffe800000 fffffbffff7fffff 16MB PCI I/O space
- fffffbffff800000 fffffbffffffffff 8MB [guard region]
- fffffc0000000000 fffffdffffffffff 2TB vmemmap
- fffffe0000000000 ffffffffffffffff 2TB [guard region]
-
-
-AArch64 Linux memory layout with 64KB pages + 3 levels (52-bit with HW support)::
-
- Start End Size Use
- -----------------------------------------------------------------------
- 0000000000000000 000fffffffffffff 4PB user
- fff0000000000000 ffff7fffffffffff ~4PB kernel logical memory map
- [fffd800000000000 ffff7fffffffffff] 512TB [kasan shadow region]
- ffff800000000000 ffff80007fffffff 2GB modules
- ffff800080000000 fffffbffefffffff 124TB vmalloc
- fffffbfff0000000 fffffbfffdffffff 224MB fixed mappings (top down)
- fffffbfffe000000 fffffbfffe7fffff 8MB [guard region]
- fffffbfffe800000 fffffbffff7fffff 16MB PCI I/O space
- fffffbffff800000 fffffbffffffffff 8MB [guard region]
- fffffc0000000000 ffffffdfffffffff ~4TB vmemmap
- ffffffe000000000 ffffffffffffffff 128GB [guard region]
-
-
-Translation table lookup with 4KB pages::
-
- +--------+--------+--------+--------+--------+--------+--------+--------+
- |63 56|55 48|47 40|39 32|31 24|23 16|15 8|7 0|
- +--------+--------+--------+--------+--------+--------+--------+--------+
- | | | | | |
- | | | | | v
- | | | | | [11:0] in-page offset
- | | | | +-> [20:12] L3 index
- | | | +-----------> [29:21] L2 index
- | | +---------------------> [38:30] L1 index
- | +-------------------------------> [47:39] L0 index
- +----------------------------------------> [55] TTBR0/1
-
-
-Translation table lookup with 64KB pages::
-
- +--------+--------+--------+--------+--------+--------+--------+--------+
- |63 56|55 48|47 40|39 32|31 24|23 16|15 8|7 0|
- +--------+--------+--------+--------+--------+--------+--------+--------+
- | | | | |
- | | | | v
- | | | | [15:0] in-page offset
- | | | +----------> [28:16] L3 index
- | | +--------------------------> [41:29] L2 index
- | +-------------------------------> [47:42] L1 index (48-bit)
- | [51:42] L1 index (52-bit)
- +----------------------------------------> [55] TTBR0/1
-
-
When using KVM without the Virtualization Host Extensions, the
hypervisor maps kernel pages in EL2 at a fixed (and potentially
random) offset from the linear mapping. See the kern_hyp_va macro and