[PATCH v2 16/24] kvm: arm64: Extract __do_hyp_init into a helper function

David Brazdil
2020-11-16T20:44:13Z

In preparation for adding a CPU entry point in nVHE hyp code, extract
most of __do_hyp_init hypervisor initialization code into a common
helper function. This will be invoked by the entry point to install KVM
on the newly booted CPU.

Signed-off-by: David Brazdil <dbrazdil@google.com>
---
arch/arm64/kvm/hyp/nvhe/hyp-init.S | 39 +++++++++++++++++++++---------
1 file changed, 28 insertions(+), 11 deletions(-)

diff --git a/arch/arm64/kvm/hyp/nvhe/hyp-init.S b/arch/arm64/kvm/hyp/nvhe/hyp-init.S
index 67342cc9930f..d4a71ac34254 100644
--- a/arch/arm64/kvm/hyp/nvhe/hyp-init.S
+++ b/arch/arm64/kvm/hyp/nvhe/hyp-init.S
@@ -68,16 +68,35 @@ __do_hyp_init:
mov x0, #SMCCC_RET_NOT_SUPPORTED
eret

-1: ldr x0, [x1, #NVHE_INIT_TPIDR_EL2]
- msr tpidr_el2, x0
+1: mov x0, x1
+ mov x4, lr
+ bl ___kvm_hyp_init
+ mov lr, x4

- ldr x0, [x1, #NVHE_INIT_VECTOR_HYP_VA]
- msr vbar_el2, x0
+ /* Hello, World! */
+ mov x0, #SMCCC_RET_SUCCESS
+ eret
+SYM_CODE_END(__kvm_hyp_init)
+
+/*
+ * Initialize the hypervisor in EL2.
+ *
+ * Only uses x0..x3 so as to not clobber callee-saved SMCCC registers
+ * and leave x4 for the caller.
+ *
+ * x0: struct kvm_nvhe_init_params PA
+ */
+SYM_CODE_START(___kvm_hyp_init)
+ ldr x1, [x0, #NVHE_INIT_TPIDR_EL2]
+ msr tpidr_el2, x1
+
+ ldr x1, [x0, #NVHE_INIT_VECTOR_HYP_VA]
+ msr vbar_el2, x1

- ldr x0, [x1, #NVHE_INIT_STACK_HYP_VA]
- mov sp, x0
+ ldr x1, [x0, #NVHE_INIT_STACK_HYP_VA]
+ mov sp, x1

- ldr x1, [x1, #NVHE_INIT_PGD_PA]
+ ldr x1, [x0, #NVHE_INIT_PGD_PA]
phys_to_ttbr x0, x1
alternative_if ARM64_HAS_CNP
orr x0, x0, #TTBR_CNP_BIT
@@ -137,10 +156,8 @@ alternative_else_nop_endif
msr sctlr_el2, x0
isb

- /* Hello, World! */
- mov x0, #SMCCC_RET_SUCCESS
- eret
-SYM_CODE_END(__kvm_hyp_init)
+ ret
+SYM_CODE_END(___kvm_hyp_init)

SYM_CODE_START(__kvm_handle_stub_hvc)
cmp x0, #HVC_SOFT_RESTART
--
2.29.2.299.gdc1121823c-goog