[coreboot-gerrit] Change in coreboot[master]: soc/amd/picasso: fix tsc_freq_mhz

[Kangheui Won (Code Review)]

Kangheui Won has uploaded this change for review. ( https://review.coreboot.org/c/coreboot/+/45054 )

Change subject: soc/amd/picasso: fix tsc_freq_mhz
......................................................................

soc/amd/picasso: fix tsc_freq_mhz

According to Core::X86::Msr::PStateDef explanation from PPR 55570,
cpufid is bit[7:0] and cpudid is bit[13:8]. And correct calcuation based
on the same section.

Signed-off-by: Kangheui Won 
Change-Id: Ia225c9d4fedc5097c8861eae73ca81c9cc344fe5
---
M src/soc/amd/picasso/tsc_freq.c
1 file changed, 3 insertions(+), 3 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/54/45054/1

diff --git a/src/soc/amd/picasso/tsc_freq.c b/src/soc/amd/picasso/tsc_freq.c
index a86080c..c3dd000 100644
--- a/src/soc/amd/picasso/tsc_freq.c
+++ b/src/soc/amd/picasso/tsc_freq.c
@@ -22,9 +22,9 @@
    if (!(msr.hi & 0x80000000))
    	die("Unknown error: cannot determine P-state 0\n");

-	cpufid = (msr.lo & 0x3f);
-	cpudid = (msr.lo & 0x1c0) >> 6;
+	cpufid = (msr.lo & 0xff);
+	cpudid = (msr.lo & 0x3f00) >> 8;

-	mhz = (100 * (cpufid + 0x10)) / (0x01 << cpudid);
+	mhz = (200 * cpufid) / cpudid;
    return mhz;
 }