New patch to review for coreboot: intel/skylake: Enable PROCHOT

[Patrick Georgi]

Patrick Georgi ([e-mail]) just uploaded a new patch set to gerrit, which you can find at https://review.coreboot.org/14120

-gerrit

commit 8e08f261a5e86b8f006d804c08bfb3511b383c26
Author: Pratik Prajapati 
Date:   Tue Mar 8 12:34:06 2016 -0800

intel/skylake: Enable PROCHOT

This patch would enable PROCHOT feature in skylake. Asserting
    PROCHOT line would throttle the GPU/CPU.

BUG=chrome-os-partner:51142
    BRANCH=glados
    TEST=manually tested on lars. asserting PROCTHOT by EC
    reduces FSP in fish-tank from approx 40 to 20. (50 fish setting),
    also CPU freq. drops to from 1600000 to 400000

Change-Id: I8fc0c015ea2c26d20bbbfc619f720f231d540feb
    Signed-off-by: Patrick Georgi 
    Original-Commit-Id: 1b88b1f183df9c7362d7e58acb0a1fa0b076d56e
    Original-Change-Id: Ida8636efc3d8da56ebd3931144d31ab1b88fe806
    Original-Signed-off-by: Pratik Prajapati 
    Original-Reviewed-on: https://chromium-review.googlesource.com/331690
    Original-Reviewed-by: Duncan Laurie 
    Original-(cherry picked from commit d091a999c3827179182b62a1274a9b3581f7f006)
    Original-Reviewed-on: https://chromium-review.googlesource.com/333073
    Original-Commit-Ready: Pratikkumar V Prajapati 
    Original-Tested-by: Pratikkumar V Prajapati 
    Original-Reviewed-by: Pratikkumar V Prajapati 
---
 src/soc/intel/skylake/cpu.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/src/soc/intel/skylake/cpu.c b/src/soc/intel/skylake/cpu.c
index d154f0e..38c5b52 100644
--- a/src/soc/intel/skylake/cpu.c
+++ b/src/soc/intel/skylake/cpu.c
@@ -252,6 +252,12 @@ static void configure_misc(void)
    msr.lo = 1 << 4;
    msr.hi = 0;
    wrmsr(IA32_PACKAGE_THERM_INTERRUPT, msr);
+
+	/* Enable PROCHOT */
+	msr = rdmsr(MSR_POWER_CTL);
+	msr.lo |= (1 << 0);	/* Enable Bi-directional PROCHOT as an input*/
+	msr.lo |= (1 << 23);	/* Lock it */
+	wrmsr(MSR_POWER_CTL, msr);
 }

static void enable_lapic_tpr(void)