diff options
| author | Marc Zyngier <marc.zyngier@arm.com> | 2012-10-26 15:40:05 +0100 |
|---|---|---|
| committer | Catalin Marinas <catalin.marinas@arm.com> | 2012-12-05 11:26:48 +0000 |
| commit | f35a92053b45cf8154db5558ede3ba5245c9dc7e (patch) | |
| tree | fc4b8d9cfcd538251db7ee8a03286bef302d6ba0 /arch/arm64/kernel | |
| parent | dc637f1fdaa6f335271a0341fef3914b80ab929c (diff) | |
arm64: record boot mode when entering the kernel
To be able to signal the availability of EL2 to other parts of
the kernel, record the boot mode.
Once booted, two predicates indicate if HYP mode is available,
and if not, whether this is due to a boot mode mismatch or not.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Diffstat (limited to 'arch/arm64/kernel')
| -rw-r--r-- | arch/arm64/kernel/head.S | 25 |
1 files changed, 22 insertions, 3 deletions
diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S index 90dec55b17a..bc6d991f8c5 100644 --- a/arch/arm64/kernel/head.S +++ b/arch/arm64/kernel/head.S @@ -31,6 +31,7 @@ #include <asm/pgtable-hwdef.h> #include <asm/pgtable.h> #include <asm/page.h> +#include <asm/virt.h> /* * swapper_pg_dir is the virtual address of the initial page table. We place @@ -115,13 +116,13 @@ ENTRY(stext) mov x21, x0 // x21=FDT + bl __calc_phys_offset // x24=PHYS_OFFSET, x28=PHYS_OFFSET-PAGE_OFFSET bl el2_setup // Drop to EL1 mrs x22, midr_el1 // x22=cpuid mov x0, x22 bl lookup_processor_type mov x23, x0 // x23=current cpu_table cbz x23, __error_p // invalid processor (x23=0)? - bl __calc_phys_offset // x24=PHYS_OFFSET, x28=PHYS_OFFSET-PAGE_OFFSET bl __vet_fdt bl __create_page_tables // x25=TTBR0, x26=TTBR1 /* @@ -147,11 +148,16 @@ 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... ret /* Hyp configuration. */ -1: mov x0, #(1 << 31) // 64-bit EL1 +1: ldr w1, =BOOT_CPU_MODE_EL2 + str w1, [x0, #4] // This CPU has EL2 + mov x0, #(1 << 31) // 64-bit EL1 msr hcr_el2, x0 /* Generic timers. */ @@ -187,6 +193,19 @@ ENTRY(el2_setup) eret ENDPROC(el2_setup) +/* + * We need to find out the CPU boot mode long after boot, so we need to + * store it in a writable variable. + * + * This is not in .bss, because we set it sufficiently early that the boot-time + * zeroing of .bss would clobber it. + */ + .pushsection .data +ENTRY(__boot_cpu_mode) + .long BOOT_CPU_MODE_EL2 + .long 0 + .popsection + .align 3 2: .quad . .quad PAGE_OFFSET @@ -202,6 +221,7 @@ ENDPROC(el2_setup) * 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 mrs x0, mpidr_el1 and x0, x0, #15 // CPU number @@ -227,7 +247,6 @@ ENTRY(secondary_startup) mov x23, x0 // x23=current cpu_table cbz x23, __error_p // invalid processor (x23=0)? - bl __calc_phys_offset // x24=phys offset pgtbl x25, x26, x24 // x25=TTBR0, x26=TTBR1 ldr x12, [x23, #CPU_INFO_SETUP] add x12, x12, x28 // __virt_to_phys |