From b6d34eb4d280c893d0f442f4b9e039d73e3db420 Mon Sep 17 00:00:00 2001 From: Anton Blanchard Date: Fri, 8 Sep 2017 03:11:12 +1000 Subject: [PATCH] powerpc: Expose TSCR via sysfs The thread switch control register (TSCR) is a per core register that configures how the CPU shares resources between SMT threads. Exposing it via sysfs allows us to tune it at run time. Signed-off-by: Anton Blanchard Signed-off-by: Michael Ellerman --- arch/powerpc/kernel/sysfs.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/arch/powerpc/kernel/sysfs.c b/arch/powerpc/kernel/sysfs.c index b8d4a1dac39f..5a8bfee6e187 100644 --- a/arch/powerpc/kernel/sysfs.c +++ b/arch/powerpc/kernel/sysfs.c @@ -485,6 +485,7 @@ SYSFS_PMCSETUP(mmcra, SPRN_MMCRA); SYSFS_SPRSETUP(purr, SPRN_PURR); SYSFS_SPRSETUP(spurr, SPRN_SPURR); SYSFS_SPRSETUP(pir, SPRN_PIR); +SYSFS_SPRSETUP(tscr, SPRN_TSCR); /* Lets only enable read for phyp resources and @@ -495,6 +496,7 @@ static DEVICE_ATTR(mmcra, 0600, show_mmcra, store_mmcra); static DEVICE_ATTR(spurr, 0400, show_spurr, NULL); static DEVICE_ATTR(purr, 0400, show_purr, store_purr); static DEVICE_ATTR(pir, 0400, show_pir, NULL); +static DEVICE_ATTR(tscr, 0600, show_tscr, store_tscr); /* * This is the system wide DSCR register default value. Any @@ -785,6 +787,9 @@ static int register_cpu_online(unsigned int cpu) if (cpu_has_feature(CPU_FTR_PPCAS_ARCH_V2)) device_create_file(s, &dev_attr_pir); + + if (cpu_has_feature(CPU_FTR_ARCH_206)) + device_create_file(s, &dev_attr_tscr); #endif /* CONFIG_PPC64 */ #ifdef CONFIG_PPC_FSL_BOOK3E @@ -867,6 +872,9 @@ static int unregister_cpu_online(unsigned int cpu) if (cpu_has_feature(CPU_FTR_PPCAS_ARCH_V2)) device_remove_file(s, &dev_attr_pir); + + if (cpu_has_feature(CPU_FTR_ARCH_206)) + device_remove_file(s, &dev_attr_tscr); #endif /* CONFIG_PPC64 */ #ifdef CONFIG_PPC_FSL_BOOK3E -- 2.20.1