From 4e543d391592929d3d9a4d16cba7cec6696c8440 Mon Sep 17 00:00:00 2001 From: Timothy Pearson Date: Tue, 24 Nov 2015 14:12:07 -0600 Subject: cpu/amd/fam10h-fam15h: Honor CMOS option to disable CPB (core boost) On certain systems and CPUs Core Performance Boost (CPB) may cause sporadic system lockups. This issue is also somewhat known on the various proprietary BIOSes, therefore it seems to be a hardware incompatibility when present. Allow the user to disable CBP if needed. Change-Id: Id6395d067d48963f6c084ad0bf79e23419af24d8 Signed-off-by: Timothy Pearson Reviewed-on: https://review.coreboot.org/13172 Tested-by: build bot (Jenkins) Reviewed-by: Felix Held --- src/cpu/amd/family_10h-family_15h/init_cpus.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) (limited to 'src/cpu') diff --git a/src/cpu/amd/family_10h-family_15h/init_cpus.c b/src/cpu/amd/family_10h-family_15h/init_cpus.c index e2a1bf3688..c1ff24042d 100644 --- a/src/cpu/amd/family_10h-family_15h/init_cpus.c +++ b/src/cpu/amd/family_10h-family_15h/init_cpus.c @@ -987,6 +987,7 @@ void cpuSetAMDMSR(uint8_t node_id) u32 platform; uint64_t revision; uint8_t enable_c_states; + uint8_t enable_cpb; printk(BIOS_DEBUG, "cpuSetAMDMSR "); @@ -1078,6 +1079,19 @@ void cpuSetAMDMSR(uint8_t node_id) enable_c_states = 0; #endif + if (revision & AMD_FAM15_ALL) { + enable_cpb = 1; + if (get_option(&nvram, "cpu_core_boost") == CB_SUCCESS) + enable_cpb = !!nvram; + + if (!enable_cpb) { + /* Disable Core Performance Boost */ + msr = rdmsr(0xc0010015); + msr.lo |= (0x1 << 25); /* CpbDis = 1 */ + wrmsr(0xc0010015, msr); + } + } + printk(BIOS_DEBUG, " done\n"); } -- cgit v1.2.3