From: Nicholas Piggin Date: Wed, 7 Feb 2024 03:52:19 +0000 (+1000) Subject: powerpc/pseries: Set CPU_FTR_DBELL according to ibm,pi-features X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=6e9de2054eb417d6e05561b19c825c29b424b475;p=linux.git powerpc/pseries: Set CPU_FTR_DBELL according to ibm,pi-features PAPR will define a new ibm,pi-features bit which says that doorbells should not be used even on architectures where they exist. This could be because they are emulated and slower than using the interrupt controller directly for IPIs. Wire this bit into the pi-features parser to clear CPU_FTR_DBELL, and ensure CPU_FTR_DBELL is not in CPU_FTRS_ALWAYS. Signed-off-by: Nicholas Piggin Tested-by: Vaibhav Jain Signed-off-by: Michael Ellerman Link: https://msgid.link/20240207035220.339726-2-npiggin@gmail.com --- diff --git a/arch/powerpc/include/asm/cputable.h b/arch/powerpc/include/asm/cputable.h index 3bd6e6e0224c8..07a204d210344 100644 --- a/arch/powerpc/include/asm/cputable.h +++ b/arch/powerpc/include/asm/cputable.h @@ -545,19 +545,20 @@ enum { #define CPU_FTRS_DT_CPU_BASE (~0ul) #endif +/* pseries may disable DBELL with ibm,pi-features */ #ifdef CONFIG_CPU_LITTLE_ENDIAN #define CPU_FTRS_ALWAYS \ - (CPU_FTRS_POSSIBLE & ~CPU_FTR_HVMODE & CPU_FTRS_POWER7 & \ - CPU_FTRS_POWER8E & CPU_FTRS_POWER8 & CPU_FTRS_POWER9 & \ - CPU_FTRS_POWER9_DD2_1 & CPU_FTRS_POWER9_DD2_2 & \ + (CPU_FTRS_POSSIBLE & ~CPU_FTR_HVMODE & ~CPU_FTR_DBELL & \ + CPU_FTRS_POWER7 & CPU_FTRS_POWER8E & CPU_FTRS_POWER8 & \ + CPU_FTRS_POWER9 & CPU_FTRS_POWER9_DD2_1 & CPU_FTRS_POWER9_DD2_2 & \ CPU_FTRS_POWER10 & CPU_FTRS_DT_CPU_BASE) #else #define CPU_FTRS_ALWAYS \ (CPU_FTRS_PPC970 & CPU_FTRS_POWER5 & \ CPU_FTRS_POWER6 & CPU_FTRS_POWER7 & CPU_FTRS_CELL & \ CPU_FTRS_PA6T & CPU_FTRS_POWER8 & CPU_FTRS_POWER8E & \ - ~CPU_FTR_HVMODE & CPU_FTRS_POSSIBLE & CPU_FTRS_POWER9 & \ - CPU_FTRS_POWER9_DD2_1 & CPU_FTRS_POWER9_DD2_2 & \ + ~CPU_FTR_HVMODE & ~CPU_FTR_DBELL & CPU_FTRS_POSSIBLE & \ + CPU_FTRS_POWER9 & CPU_FTRS_POWER9_DD2_1 & CPU_FTRS_POWER9_DD2_2 & \ CPU_FTRS_POWER10 & CPU_FTRS_DT_CPU_BASE) #endif /* CONFIG_CPU_LITTLE_ENDIAN */ #endif diff --git a/arch/powerpc/kernel/prom.c b/arch/powerpc/kernel/prom.c index 25c414be92dba..1dc32a0581561 100644 --- a/arch/powerpc/kernel/prom.c +++ b/arch/powerpc/kernel/prom.c @@ -196,6 +196,7 @@ static struct ibm_feature ibm_pa_features[] __initdata = { */ static struct ibm_feature ibm_pi_features[] __initdata = { { .pabyte = 0, .pabit = 3, .mmu_features = MMU_FTR_NX_DSI }, + { .pabyte = 0, .pabit = 4, .cpu_features = CPU_FTR_DBELL, .clear = 1 }, }; static void __init scan_features(unsigned long node, const unsigned char *ftrs,