Change in coreboot[master]: mb/google/dedede: Enable "FastPkgCRampDisable" upd for noise mitigation

[Karthik Ramasubramanian (Code Review)]

Karthik Ramasubramanian has submitted this change. ( https://review.coreboot.org/c/coreboot/+/49134 )

Change subject: mb/google/dedede: Enable "FastPkgCRampDisable" upd for noise mitigation
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mb/google/dedede: Enable "FastPkgCRampDisable" upd for noise mitigation

As part of acoustic noise mitigation calibration, we need to enable
FastPkgCRampDisable upd along with slew rate = 1. This values has been
derived based on noise calibration done.

Please refer document 575216 for procedure.

BUG=None
BRANCH=dedede
TEST=correct value has been programmed and slew rate measurement
is correct on scope.

Change-Id: Ie42c8ab647ff42fa043b6f717a9834f9b9c551f6
Signed-off-by: Maulik V Vaghela 
Reviewed-on: https://review.coreboot.org/c/coreboot/+/49134
Tested-by: build bot (Jenkins) 
Reviewed-by: Furquan Shaikh 
Reviewed-by: Karthik Ramasubramanian 
Reviewed-by: Evan Green 
---
M src/mainboard/google/dedede/variants/drawcia/overridetree.cb
1 file changed, 2 insertions(+), 1 deletion(-)

Approvals:
  build bot (Jenkins): Verified
  Furquan Shaikh: Looks good to me, approved
  Evan Green: Looks good to me, approved
  Karthik Ramasubramanian: Looks good to me, approved

diff --git a/src/mainboard/google/dedede/variants/drawcia/overridetree.cb b/src/mainboard/google/dedede/variants/drawcia/overridetree.cb
index e09dbe8..5959343 100644
--- a/src/mainboard/google/dedede/variants/drawcia/overridetree.cb
+++ b/src/mainboard/google/dedede/variants/drawcia/overridetree.cb
@@ -67,7 +67,8 @@
    # Enable Acoustic noise mitigation and set slew rate to 1/4
         # Rest of the parameters are 0 by default.
    register "AcousticNoiseMitigation" = "1"
-	register "SlowSlewRate" = "1"
+	register "SlowSlewRate" = "SlewRateFastBy4"
+	register "FastPkgCRampDisable" = "1"

device domain 0 on
    	device pci 05.0 on # IPU - MIPI Camera