From: Ard Biesheuvel ard.biesheuvel@linaro.org
The adrp instruction is mostly used in combination with either an add, a ldr or a str instruction with the low bits of the referenced symbol in the 12-bit immediate of the followup instruction.
Introduce the macros adr_l, ldr_l and str_l that encapsulate these common patterns.
Tested-by: Mark Rutland mark.rutland@arm.com 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 (cherry picked from commit b784a5d97d0af4835dd0125a3e0e5d0fd48128d6) Signed-off-by: Alex Shi alex.shi@linaro.org --- arch/arm64/include/asm/assembler.h | 48 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 48 insertions(+)
diff --git a/arch/arm64/include/asm/assembler.h b/arch/arm64/include/asm/assembler.h index 750bac4..144b64a 100644 --- a/arch/arm64/include/asm/assembler.h +++ b/arch/arm64/include/asm/assembler.h @@ -159,4 +159,52 @@ lr .req x30 // link register orr \rd, \lbits, \hbits, lsl #32 .endm
+/* + * Pseudo-ops for PC-relative adr/ldr/str <reg>, <symbol> where + * <symbol> is within the range +/- 4 GB of the PC. + */ + /* + * @dst: destination register (64 bit wide) + * @sym: name of the symbol + * @tmp: optional scratch register to be used if <dst> == sp, which + * is not allowed in an adrp instruction + */ + .macro adr_l, dst, sym, tmp= + .ifb \tmp + adrp \dst, \sym + add \dst, \dst, :lo12:\sym + .else + adrp \tmp, \sym + add \dst, \tmp, :lo12:\sym + .endif + .endm + + /* + * @dst: destination register (32 or 64 bit wide) + * @sym: name of the symbol + * @tmp: optional 64-bit scratch register to be used if <dst> is a + * 32-bit wide register, in which case it cannot be used to hold + * the address + */ + .macro ldr_l, dst, sym, tmp= + .ifb \tmp + adrp \dst, \sym + ldr \dst, [\dst, :lo12:\sym] + .else + adrp \tmp, \sym + ldr \dst, [\tmp, :lo12:\sym] + .endif + .endm + + /* + * @src: source register (32 or 64 bit wide) + * @sym: name of the symbol + * @tmp: mandatory 64-bit scratch register to calculate the address + * while <src> needs to be preserved. + */ + .macro str_l, src, sym, tmp + adrp \tmp, \sym + str \src, [\tmp, :lo12:\sym] + .endm + #endif /* __ASM_ASSEMBLER_H */