From: Mark Rutland mark.rutland@arm.com
commit 3ad47d055aa88d9f4189253f5b5c485f4c4626b2 upstream.
The early el2_setup code is a little convoluted, with two branches where one would do. This makes the code more painful to read than is necessary.
We can remove a branch and simplify the logic by moving the early return in the booted-at-EL1 case earlier in the function. This separates it from all the setup logic that only makes sense for EL2.
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 | 15 +++++++-------- 1 file changed, 7 insertions(+), 8 deletions(-)
--- a/arch/arm64/kernel/head.S +++ b/arch/arm64/kernel/head.S @@ -489,13 +489,8 @@ ENTRY(el2_setup) msr SPsel, #1 // We want to use SP_EL{1,2} mrs x0, CurrentEL cmp x0, #CurrentEL_EL2 - b.ne 1f - mrs x0, sctlr_el2 -CPU_BE( orr x0, x0, #(1 << 25) ) // Set the EE bit for EL2 -CPU_LE( bic x0, x0, #(1 << 25) ) // Clear the EE bit for EL2 - msr sctlr_el2, x0 - b 2f -1: mrs x0, sctlr_el1 + b.eq 1f + mrs x0, sctlr_el1 CPU_BE( orr x0, x0, #(3 << 24) ) // Set the EE and E0E bits for EL1 CPU_LE( bic x0, x0, #(3 << 24) ) // Clear the EE and E0E bits for EL1 msr sctlr_el1, x0 @@ -503,7 +498,11 @@ CPU_LE( bic x0, x0, #(3 << 24) ) // Clea isb ret
-2: +1: mrs x0, sctlr_el2 +CPU_BE( orr x0, x0, #(1 << 25) ) // Set the EE bit for EL2 +CPU_LE( bic x0, x0, #(1 << 25) ) // Clear the EE bit for EL2 + msr sctlr_el2, x0 + #ifdef CONFIG_ARM64_VHE /* * Check for VHE being present. For the rest of the EL2 setup,