From: Mark Rutland mark.rutland@arm.com
commit d61c97a7773d0848b4bf5c4697855c7ce117362c upstream.
We only need to initialise sctlr_el1 if we're installing an EL2 stub, so we may as well defer this until we're doing so. Similarly, we can defer intialising CPTR_EL2 until then, as we do not access any trapped functionality as part of el2_setup.
This patch modified el2_setup accordingly, allowing us to remove a branch and simplify the code flow.
Acked-by: Marc Zyngier marc.zyngier@arm.com Signed-off-by: Mark Rutland mark.rutland@arm.com Cc: Will Deacon will.deacon@arm.com Signed-off-by: Catalin Marinas catalin.marinas@arm.com Signed-off-by: Nathan Chancellor nathan@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- arch/arm64/kernel/head.S | 37 +++++++++++++++++-------------------- 1 file changed, 17 insertions(+), 20 deletions(-)
--- a/arch/arm64/kernel/head.S +++ b/arch/arm64/kernel/head.S @@ -553,26 +553,6 @@ set_hcr: msr vpidr_el2, x0 msr vmpidr_el2, x1
- /* - * When VHE is not in use, early init of EL2 and EL1 needs to be - * done here. - * When VHE _is_ in use, EL1 will not be used in the host and - * requires no configuration, and all non-hyp-specific EL2 setup - * will be done via the _EL1 system register aliases in __cpu_setup. - */ - cbnz x2, 1f - - /* sctlr_el1 */ - mov x0, #0x0800 // Set/clear RES{1,0} bits -CPU_BE( movk x0, #0x33d0, lsl #16 ) // Set EE and E0E on BE systems -CPU_LE( movk x0, #0x30d0, lsl #16 ) // Clear EE and E0E on LE systems - msr sctlr_el1, x0 - - /* Coprocessor traps. */ - mov x0, #0x33ff - msr cptr_el2, x0 // Disable copro. traps to EL2 -1: - #ifdef CONFIG_COMPAT msr hstr_el2, xzr // Disable CP15 traps to EL2 #endif @@ -598,6 +578,23 @@ CPU_LE( movk x0, #0x30d0, lsl #16 ) // C ret
install_el2_stub: + /* + * When VHE is not in use, early init of EL2 and EL1 needs to be + * done here. + * When VHE _is_ in use, EL1 will not be used in the host and + * requires no configuration, and all non-hyp-specific EL2 setup + * will be done via the _EL1 system register aliases in __cpu_setup. + */ + /* sctlr_el1 */ + mov x0, #0x0800 // Set/clear RES{1,0} bits +CPU_BE( movk x0, #0x33d0, lsl #16 ) // Set EE and E0E on BE systems +CPU_LE( movk x0, #0x30d0, lsl #16 ) // Clear EE and E0E on LE systems + msr sctlr_el1, x0 + + /* Coprocessor traps. */ + mov x0, #0x33ff + msr cptr_el2, x0 // Disable copro. traps to EL2 + /* Hypervisor stub */ adrp x0, __hyp_stub_vectors add x0, x0, #:lo12:__hyp_stub_vectors