diff options
| author | Matthew Leach <matthew.leach@arm.com> | 2013-10-11 14:52:16 +0100 |
|---|---|---|
| committer | Catalin Marinas <catalin.marinas@arm.com> | 2013-10-25 15:59:39 +0100 |
| commit | 828e9834e9a5b7e61046aa3c5f603a4fecba2fb4 (patch) | |
| tree | 0a0e3cd11b88f88b718e71fcb7990152486cf1a7 /arch/arm64/kernel/head.S | |
| parent | e68bedaa03c950ae8045e7899e7a6b2a97d1bf41 (diff) | |
arm64: head: create a new function for setting the boot_cpu_mode flag
Currently, the code for setting the __cpu_boot_mode flag is munged in
with el2_setup. This makes things difficult on a BE bringup as a
memory access has to have occurred before el2_setup which is the place
that we'd like to set the endianess on the current EL.
Create a new function for setting __cpu_boot_mode and have el2_setup
return the mode the CPU. Also define a new constant in virt.h,
BOOT_CPU_MODE_EL1, for readability.
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Matthew Leach <matthew.leach@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Diffstat (limited to 'arch/arm64/kernel/head.S')
| -rw-r--r-- | arch/arm64/kernel/head.S | 34 |
1 files changed, 25 insertions, 9 deletions
diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S index bf7efdf2d7e7..775ecb313ee7 100644 --- a/arch/arm64/kernel/head.S +++ b/arch/arm64/kernel/head.S @@ -123,8 +123,9 @@ ENTRY(stext) mov x21, x0 // x21=FDT + bl el2_setup // Drop to EL1, w20=cpu_boot_mode bl __calc_phys_offset // x24=PHYS_OFFSET, x28=PHYS_OFFSET-PAGE_OFFSET - bl el2_setup // Drop to EL1 + bl set_cpu_boot_mode_flag mrs x22, midr_el1 // x22=cpuid mov x0, x22 bl lookup_processor_type @@ -150,21 +151,20 @@ ENDPROC(stext) /* * If we're fortunate enough to boot at EL2, ensure that the world is * sane before dropping to EL1. + * + * Returns either BOOT_CPU_MODE_EL1 or BOOT_CPU_MODE_EL2 in x20 if + * booted in EL1 or EL2 respectively. */ ENTRY(el2_setup) mrs x0, CurrentEL cmp x0, #PSR_MODE_EL2t ccmp x0, #PSR_MODE_EL2h, #0x4, ne - ldr x0, =__boot_cpu_mode // Compute __boot_cpu_mode - add x0, x0, x28 b.eq 1f - str wzr, [x0] // Remember we don't have EL2... + mov w20, #BOOT_CPU_MODE_EL1 // This cpu booted in EL1 ret /* Hyp configuration. */ -1: ldr w1, =BOOT_CPU_MODE_EL2 - str w1, [x0, #4] // This CPU has EL2 - mov x0, #(1 << 31) // 64-bit EL1 +1: mov x0, #(1 << 31) // 64-bit EL1 msr hcr_el2, x0 /* Generic timers. */ @@ -204,10 +204,25 @@ ENTRY(el2_setup) PSR_MODE_EL1h) msr spsr_el2, x0 msr elr_el2, lr + mov w20, #BOOT_CPU_MODE_EL2 // This CPU booted in EL2 eret ENDPROC(el2_setup) /* + * Sets the __boot_cpu_mode flag depending on the CPU boot mode passed + * in x20. See arch/arm64/include/asm/virt.h for more info. + */ +ENTRY(set_cpu_boot_mode_flag) + ldr x1, =__boot_cpu_mode // Compute __boot_cpu_mode + add x1, x1, x28 + cmp w20, #BOOT_CPU_MODE_EL2 + b.ne 1f + add x1, x1, #4 +1: str w20, [x1] // This CPU has booted in EL1 + ret +ENDPROC(set_cpu_boot_mode_flag) + +/* * We need to find out the CPU boot mode long after boot, so we need to * store it in a writable variable. * @@ -234,8 +249,9 @@ ENTRY(__boot_cpu_mode) * cores are held until we're ready for them to initialise. */ ENTRY(secondary_holding_pen) - bl __calc_phys_offset // x24=phys offset - bl el2_setup // Drop to EL1 + bl el2_setup // Drop to EL1, w20=cpu_boot_mode + bl __calc_phys_offset // x24=PHYS_OFFSET, x28=PHYS_OFFSET-PAGE_OFFSET + bl set_cpu_boot_mode_flag mrs x0, mpidr_el1 ldr x1, =MPIDR_HWID_BITMASK and x0, x0, x1 |