From: Alistair Popple Date: Wed, 6 May 2020 03:40:41 +0000 (+1000) Subject: powerpc: Enable Prefixed Instructions X-Git-Tag: Ubuntu-5.10.0-12.13~2701^2~129 X-Git-Url: https://git.proxmox.com/?a=commitdiff_plain;h=2aa6195e43b3740258ead93aee42ac719dd4c4b0;p=mirror_ubuntu-hirsute-kernel.git powerpc: Enable Prefixed Instructions Prefix instructions have their own FSCR bit which needs to enabled via a CPU feature. The kernel will save the FSCR for problem state but it needs to be enabled initially. If prefixed instructions are made unavailable by the [H]FSCR, attempting to use them will cause a facility unavailable exception. Add "PREFIX" to the facility_strings[]. Currently there are no prefixed instructions that are actually emulated by emulate_instruction() within facility_unavailable_exception(). However, when caused by a prefixed instructions the SRR1 PREFIXED bit is set. Prepare for dealing with emulated prefixed instructions by checking for this bit. Signed-off-by: Alistair Popple Signed-off-by: Jordan Niethe Signed-off-by: Michael Ellerman Reviewed-by: Nicholas Piggin Link: https://lore.kernel.org/r/20200506034050.24806-22-jniethe5@gmail.com --- diff --git a/arch/powerpc/include/asm/reg.h b/arch/powerpc/include/asm/reg.h index da5cab038e25..773f76402392 100644 --- a/arch/powerpc/include/asm/reg.h +++ b/arch/powerpc/include/asm/reg.h @@ -397,6 +397,7 @@ #define SPRN_RWMR 0x375 /* Region-Weighting Mode Register */ /* HFSCR and FSCR bit numbers are the same */ +#define FSCR_PREFIX_LG 13 /* Enable Prefix Instructions */ #define FSCR_SCV_LG 12 /* Enable System Call Vectored */ #define FSCR_MSGP_LG 10 /* Enable MSGP */ #define FSCR_TAR_LG 8 /* Enable Target Address Register */ @@ -408,11 +409,13 @@ #define FSCR_VECVSX_LG 1 /* Enable VMX/VSX */ #define FSCR_FP_LG 0 /* Enable Floating Point */ #define SPRN_FSCR 0x099 /* Facility Status & Control Register */ +#define FSCR_PREFIX __MASK(FSCR_PREFIX_LG) #define FSCR_SCV __MASK(FSCR_SCV_LG) #define FSCR_TAR __MASK(FSCR_TAR_LG) #define FSCR_EBB __MASK(FSCR_EBB_LG) #define FSCR_DSCR __MASK(FSCR_DSCR_LG) #define SPRN_HFSCR 0xbe /* HV=1 Facility Status & Control Register */ +#define HFSCR_PREFIX __MASK(FSCR_PREFIX_LG) #define HFSCR_MSGP __MASK(FSCR_MSGP_LG) #define HFSCR_TAR __MASK(FSCR_TAR_LG) #define HFSCR_EBB __MASK(FSCR_EBB_LG) diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c index 477befcda8d3..e37bf7945d27 100644 --- a/arch/powerpc/kernel/traps.c +++ b/arch/powerpc/kernel/traps.c @@ -1737,6 +1737,7 @@ void facility_unavailable_exception(struct pt_regs *regs) [FSCR_TAR_LG] = "TAR", [FSCR_MSGP_LG] = "MSGP", [FSCR_SCV_LG] = "SCV", + [FSCR_PREFIX_LG] = "PREFIX", }; char *facility = "unknown"; u64 value;