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| author | Ard Biesheuvel <ard.biesheuvel@linaro.org> | 2016-08-31 12:05:12 +0100 |
|---|---|---|
| committer | Will Deacon <will.deacon@arm.com> | 2016-09-02 11:21:15 +0100 |
| commit | 23c8a500c24d02dd2de1bff968d4467b441717bb (patch) | |
| tree | cd9c8c84ff541c789128870d75d26ba38b70dd18 /arch/arm64/kernel | |
| parent | b5fe242972ef3faaa6bcfe66cbacc7a0014faf89 (diff) | |
| download | blackbird-obmc-linux-23c8a500c24d02dd2de1bff968d4467b441717bb.tar.gz blackbird-obmc-linux-23c8a500c24d02dd2de1bff968d4467b441717bb.zip | |
arm64: kernel: use ordinary return/argument register for el2_setup()
The function el2_setup() passes its return value in register w20, and
in the two cases where the caller actually cares about this return value,
it is passed into set_cpu_boot_mode_flag() [almost] directly, which
expects its input in w20 as well.
So there is no reason to use a 'special' callee saved register here, but
we can simply follow the PCS for return value and first argument,
respectively.
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Diffstat (limited to 'arch/arm64/kernel')
| -rw-r--r-- | arch/arm64/kernel/head.S | 14 |
1 files changed, 7 insertions, 7 deletions
diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S index 9ee9666c2e34..be02c5593ba6 100644 --- a/arch/arm64/kernel/head.S +++ b/arch/arm64/kernel/head.S @@ -210,7 +210,7 @@ efi_header_end: ENTRY(stext) bl preserve_boot_args - bl el2_setup // Drop to EL1, w20=cpu_boot_mode + bl el2_setup // Drop to EL1, w0=cpu_boot_mode adrp x24, __PHYS_OFFSET and x23, x24, MIN_KIMG_ALIGN - 1 // KASLR offset, defaults to 0 bl set_cpu_boot_mode_flag @@ -488,7 +488,7 @@ CPU_LE( bic x0, x0, #(1 << 25) ) // Clear the EE bit for EL2 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 - mov w20, #BOOT_CPU_MODE_EL1 // This cpu booted in EL1 + mov w0, #BOOT_CPU_MODE_EL1 // This cpu booted in EL1 isb ret @@ -584,7 +584,7 @@ CPU_LE( movk x0, #0x30d0, lsl #16 ) // Clear EE and E0E on LE systems cbz x2, install_el2_stub - mov w20, #BOOT_CPU_MODE_EL2 // This CPU booted in EL2 + mov w0, #BOOT_CPU_MODE_EL2 // This CPU booted in EL2 isb ret @@ -599,7 +599,7 @@ install_el2_stub: PSR_MODE_EL1h) msr spsr_el2, x0 msr elr_el2, lr - mov w20, #BOOT_CPU_MODE_EL2 // This CPU booted in EL2 + mov w0, #BOOT_CPU_MODE_EL2 // This CPU booted in EL2 eret ENDPROC(el2_setup) @@ -609,10 +609,10 @@ ENDPROC(el2_setup) */ set_cpu_boot_mode_flag: adr_l x1, __boot_cpu_mode - cmp w20, #BOOT_CPU_MODE_EL2 + cmp w0, #BOOT_CPU_MODE_EL2 b.ne 1f add x1, x1, #4 -1: str w20, [x1] // This CPU has booted in EL1 +1: str w0, [x1] // This CPU has booted in EL1 dmb sy dc ivac, x1 // Invalidate potentially stale cache line ret @@ -649,7 +649,7 @@ ENTRY(__early_cpu_boot_status) * cores are held until we're ready for them to initialise. */ ENTRY(secondary_holding_pen) - bl el2_setup // Drop to EL1, w20=cpu_boot_mode + bl el2_setup // Drop to EL1, w0=cpu_boot_mode bl set_cpu_boot_mode_flag mrs x0, mpidr_el1 mov_q x1, MPIDR_HWID_BITMASK |
