summaryrefslogtreecommitdiff
path: root/src/arch/arm64/transition_asm.S
diff options
context:
space:
mode:
authorJulius Werner <jwerner@chromium.org>2015-10-12 16:45:21 -0700
committerJulius Werner <jwerner@chromium.org>2015-11-16 21:53:43 +0100
commit66a476ad5f29553ad7c46e58eb35faa7a059a5af (patch)
tree2fcb80dc3cc7f578d20d04952641192dcccf4ad1 /src/arch/arm64/transition_asm.S
parent29016ea3b4350d8c9ed5fad8dff7707ecbb21127 (diff)
downloadcoreboot-66a476ad5f29553ad7c46e58eb35faa7a059a5af.tar.xz
arm64: Implement generic stage transitions for non-Tegra SoCs
The existing arm64 architecture code has been developed for the Tegra132 and Tegra210 SoCs, which only start their ARM64 cores in ramstage. It interweaves the stage entry point with code that initializes a CPU (and should not be run again if that CPU already ran a previous stage). It also still contains some vestiges of SMP/secmon support (such as setting up stacks in the BSS instead of using the stage-peristent one from memlayout). This patch splits those functions apart and makes the code layout similar to how things work on ARM32. The default stage_entry() symbol is a no-op wrapper that just calls main() for the current stage, for the normal case where a stage ran on the same core as the last one. It can be overridden by SoC code to support special cases like Tegra. The CPU initialization code is split out into armv8/cpu.S (similar to what arm_init_caches() does for ARM32) and called by the default bootblock entry code. SoCs where a CPU starts up in a later stage can call the same code from a stage_entry() override instead. The Tegra132 and Tegra210 code is not touched by this patch to make it easier to review and validate. A follow-up patch will bring those SoCs in line with the model. BRANCH=None BUG=None TEST=Booted Oak with a single mmu_init()/mmu_enable(). Built Ryu and Smaug. Change-Id: I28302a6ace47e8ab7a736e089f64922cef1a2f93 Signed-off-by: Julius Werner <jwerner@chromium.org> Reviewed-on: http://review.coreboot.org/12077 Tested-by: build bot (Jenkins) Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Diffstat (limited to 'src/arch/arm64/transition_asm.S')
-rw-r--r--src/arch/arm64/transition_asm.S13
1 files changed, 10 insertions, 3 deletions
diff --git a/src/arch/arm64/transition_asm.S b/src/arch/arm64/transition_asm.S
index 24eab13fa2..8fd629a8af 100644
--- a/src/arch/arm64/transition_asm.S
+++ b/src/arch/arm64/transition_asm.S
@@ -155,11 +155,18 @@ ENTRY(exc_exit)
eret
ENDPROC(exc_exit)
-/* exc_set_vbar: Initialize the exception entry address in vbar */
-ENTRY(exc_set_vbar)
+/*
+ * exception_init_asm: Initialize VBAR and point SP_EL3 to exception stack.
+ * x0 = end of exception stack
+ */
+ENTRY(exception_init_asm)
+ msr SPSel, #SPSR_USE_H
+ mov sp, x0
+ msr SPSel, #SPSR_USE_L
+
adr x0, exc_vectors
write_current vbar, x0, x1
dsb sy
isb
ret
-ENDPROC(exc_set_vbar)
+ENDPROC(exception_init_asm)