From 8d56e5c5a99ce1d17d39ce5a8260e42c2a2d7682 Mon Sep 17 00:00:00 2001 From: Alexandru Elisei Date: Mon, 25 Apr 2022 12:44:42 +0100 Subject: arm64: Treat ESR_ELx as a 64-bit register In the initial release of the ARM Architecture Reference Manual for ARMv8-A, the ESR_ELx registers were defined as 32-bit registers. This changed in 2018 with version D.a (ARM DDI 0487D.a) of the architecture, when they became 64-bit registers, with bits [63:32] defined as RES0. In version G.a, a new field was added to ESR_ELx, ISS2, which covers bits [36:32]. This field is used when the Armv8.7 extension FEAT_LS64 is implemented. As a result of the evolution of the register width, Linux stores it as both a 64-bit value and a 32-bit value, which hasn't affected correctness so far as Linux only uses the lower 32 bits of the register. Make the register type consistent and always treat it as 64-bit wide. The register is redefined as an "unsigned long", which is an unsigned double-word (64-bit quantity) for the LP64 machine (aapcs64 [1], Table 1, page 14). The type was chosen because "unsigned int" is the most frequent type for ESR_ELx and because FAR_ELx, which is used together with ESR_ELx in exception handling, is also declared as "unsigned long". The 64-bit type also makes adding support for architectural features that use fields above bit 31 easier in the future. The KVM hypervisor will receive a similar update in a subsequent patch. [1] https://github.com/ARM-software/abi-aa/releases/download/2021Q3/aapcs64.pdf Signed-off-by: Alexandru Elisei Reviewed-by: Marc Zyngier Link: https://lore.kernel.org/r/20220425114444.368693-4-alexandru.elisei@arm.com Signed-off-by: Catalin Marinas --- arch/arm64/include/asm/esr.h | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'arch/arm64/include/asm/esr.h') diff --git a/arch/arm64/include/asm/esr.h b/arch/arm64/include/asm/esr.h index 7356e2f05755..9d18f82c57d5 100644 --- a/arch/arm64/include/asm/esr.h +++ b/arch/arm64/include/asm/esr.h @@ -330,14 +330,14 @@ #ifndef __ASSEMBLY__ #include -static inline bool esr_is_data_abort(u32 esr) +static inline bool esr_is_data_abort(unsigned long esr) { - const u32 ec = ESR_ELx_EC(esr); + const unsigned long ec = ESR_ELx_EC(esr); return ec == ESR_ELx_EC_DABT_LOW || ec == ESR_ELx_EC_DABT_CUR; } -const char *esr_get_class_string(u32 esr); +const char *esr_get_class_string(unsigned long esr); #endif /* __ASSEMBLY */ #endif /* __ASM_ESR_H */ -- cgit