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authorPeter Hoyes <Peter.Hoyes@arm.com>2022-03-04 19:30:18 +0300
committerTom Rini <trini@konsulko.com>2022-04-01 22:03:03 +0300
commit8d78a6b67467145f7e02295ca5d4944251dbc645 (patch)
treed7740ca3f69063f5ed0e37eed78dc222c529a381 /doc/arch
parent1a1143a45457161e90ea4cd5f3b0561d924ed8fe (diff)
downloadu-boot-8d78a6b67467145f7e02295ca5d4944251dbc645.tar.xz
vexpress64: Add ARMv8R-64 board variant
The ARMv8-R64 architecture introduces optional VMSA (paging based MMU) support in the EL1/0 translation regime, which makes that part mostly compatible to ARMv8-A. Add a new board variant to describe the "BASE-R64" FVP model, which inherits a lot from the existing v8-A FVP support. One major difference is that the memory map in "inverted": DRAM starts at 0x0, MMIO is at 2GB [1]. * Create new TARGET_VEXPRESS64_BASER_FVP target, sharing most of the exising configuration. * Implement inverted memory map in vexpress_aemv8.h * Create vexpress_aemv8r defconfig * Provide an MMU memory map for the BASER_FVP * Update vexpress64 documentation At the moment the boot-wrapper is the only supported secure firmware. As there is no official DT for the board yet, we rely on it being supplied by the boot-wrapper into U-Boot, so use OF_HAS_PRIOR_STAGE, and go with a dummy DT for now. [1] https://developer.arm.com/documentation/100964/1114/Base-Platform/Base---memory/BaseR-Platform-memory-map Signed-off-by: Peter Hoyes <Peter.Hoyes@arm.com> [Andre: rebase and add Linux kernel header] Signed-off-by: Andre Przywara <andre.przywara@arm.com> [trini: Add MAINTAINERS entry for Peter]
Diffstat (limited to 'doc/arch')
-rw-r--r--doc/arch/arm64.rst3
1 files changed, 2 insertions, 1 deletions
diff --git a/doc/arch/arm64.rst b/doc/arch/arm64.rst
index 80498f6f6b..7c0713504c 100644
--- a/doc/arch/arm64.rst
+++ b/doc/arch/arm64.rst
@@ -18,7 +18,8 @@ Notes
classical firmware (like initial hardware setup, CPU errata workarounds
or SMP bringup). U-Boot can be entered in EL2 when its main purpose is
that of a boot loader. It can drop to lower exception levels before
- entering the OS.
+ entering the OS. For ARMv8-R it is recommened to enter at S-EL1, as for this
+ architecture there is no S-EL3.
2. U-Boot for arm64 is compiled with AArch64-gcc. AArch64-gcc
use rela relocation format, a tool(tools/relocate-rela) by Scott Wood