diff options
Diffstat (limited to 'arch/arm64/include/asm/assembler.h')
| -rw-r--r-- | arch/arm64/include/asm/assembler.h | 40 |
1 files changed, 40 insertions, 0 deletions
diff --git a/arch/arm64/include/asm/assembler.h b/arch/arm64/include/asm/assembler.h index 463619dcadd4..25b2a4161c7a 100644 --- a/arch/arm64/include/asm/assembler.h +++ b/arch/arm64/include/asm/assembler.h @@ -25,6 +25,7 @@ #include <asm/asm-offsets.h> #include <asm/cpufeature.h> +#include <asm/cputype.h> #include <asm/page.h> #include <asm/pgtable-hwdef.h> #include <asm/ptrace.h> @@ -495,4 +496,43 @@ alternative_endif and \phys, \pte, #(((1 << (48 - PAGE_SHIFT)) - 1) << PAGE_SHIFT) .endm +/* + * Check the MIDR_EL1 of the current CPU for a given model and a range of + * variant/revision. See asm/cputype.h for the macros used below. + * + * model: MIDR_CPU_MODEL of CPU + * rv_min: Minimum of MIDR_CPU_VAR_REV() + * rv_max: Maximum of MIDR_CPU_VAR_REV() + * res: Result register. + * tmp1, tmp2, tmp3: Temporary registers + * + * Corrupts: res, tmp1, tmp2, tmp3 + * Returns: 0, if the CPU id doesn't match. Non-zero otherwise + */ + .macro cpu_midr_match model, rv_min, rv_max, res, tmp1, tmp2, tmp3 + mrs \res, midr_el1 + mov_q \tmp1, (MIDR_REVISION_MASK | MIDR_VARIANT_MASK) + mov_q \tmp2, MIDR_CPU_MODEL_MASK + and \tmp3, \res, \tmp2 // Extract model + and \tmp1, \res, \tmp1 // rev & variant + mov_q \tmp2, \model + cmp \tmp3, \tmp2 + cset \res, eq + cbz \res, .Ldone\@ // Model matches ? + + .if (\rv_min != 0) // Skip min check if rv_min == 0 + mov_q \tmp3, \rv_min + cmp \tmp1, \tmp3 + cset \res, ge + .endif // \rv_min != 0 + /* Skip rv_max check if rv_min == rv_max && rv_min != 0 */ + .if ((\rv_min != \rv_max) || \rv_min == 0) + mov_q \tmp2, \rv_max + cmp \tmp1, \tmp2 + cset \tmp2, le + and \res, \res, \tmp2 + .endif +.Ldone\@: + .endm + #endif /* __ASM_ASSEMBLER_H */ |