mb/google/kahlee/variants/baseboard: Set STAPM percentage

Default STAPM percentage causes a lot of thermal throttling on grunt.
AMD experimented with 80%, it works for grunt. This is initial code to
provide easy change path for other grunt based platforms.

BUG=b:111608748
TEST=build and boot grunt.

Change-Id: I22863f6ed76152bf872fce3e275f8a7fd8077504
Signed-off-by: Richard Spiegel <richard.spiegel@silverbackltd.com>
Reviewed-on: https://review.coreboot.org/28564
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Martin Roth <martinroth@google.com>

src/mainboard/google/kahlee/variants/baseboard/OemCustomize.c

@@ -17,6 +17,8 @@
 #include <amdblocks/agesawrapper.h>
 #include <variant/gpio.h>
 #include <boardid.h>
+#include <chip.h>
+#include <soc/pci_devs.h>
 
 static const PCIe_PORT_DESCRIPTOR PortList[] = {
 	/* Initialize Port descriptor (PCIe port, Lanes 7:4, D2F1) for NC*/
@@ -147,8 +149,27 @@ static const PCIe_COMPLEX_DESCRIPTOR PcieComplex = {
 /*---------------------------------------------------------------------------*/
 VOID __weak OemCustomizeInitEarly(IN OUT AMD_EARLY_PARAMS *InitEarly)
 {
+	const struct soc_amd_stoneyridge_config *cfg;
+	const struct device *dev = dev_find_slot(0, GNB_DEVFN);
+	struct _PLATFORM_CONFIGURATION *platform;
+
 	InitEarly->GnbConfig.PcieComplexList = (void *)&PcieComplex;
 	InitEarly->GnbConfig.PsppPolicy = PsppBalanceLow;
 	InitEarly->PlatformConfig.GnbAzI2sBusSelect = GnbAcpI2sBus;
 	InitEarly->PlatformConfig.GnbAzI2sBusPinConfig = GnbAcp2Tx4RxBluetooth;
+	if (!dev || !dev->chip_info) {
+		printk(BIOS_WARNING, "Warning: Cannot find SoC devicetree"
+					" config, STAPM unchanged\n");
+		return;
+	}
+	cfg = dev->chip_info;
+	platform = &InitEarly->PlatformConfig;
+	if ((cfg->stapm_percent) && (cfg->stapm_time) && (cfg->stapm_power)) {
+		platform->PlatStapmConfig.CfgStapmScalar = cfg->stapm_percent;
+		platform->PlatStapmConfig.CfgStapmTimeConstant =
+							cfg->stapm_time;
+		platform->PkgPwrLimitDC = cfg->stapm_power;
+		platform->PkgPwrLimitAC = cfg->stapm_power;
+		platform->PlatStapmConfig.CfgStapmBoost = StapmBoostEnabled;
+	}
 }

src/mainboard/google/kahlee/variants/grunt/devicetree.cb

@@ -20,6 +20,9 @@ chip soc/amd/stoneyridge
 	register "dram_clear_on_reset" = "DRAM_CONTENTS_KEEP"
 	register "uma_mode" = "UMAMODE_SPECIFIED_SIZE"
 	register "uma_size" = "32 * MiB"
+	register "stapm_percent" = "80"
+	register "stapm_time" = "2500"
+	register "stapm_power" = "7800"
 
 	# Enable I2C0 for audio, USB3 hub at 400kHz
 	register "i2c[0]" = "{

src/soc/amd/stoneyridge/chip.h

@@ -51,6 +51,9 @@ struct soc_amd_stoneyridge_config {
 	size_t uma_size;
 
 	struct dw_i2c_bus_config i2c[STONEY_I2C_DEV_MAX];
+	u8 stapm_percent;
+	u32 stapm_time;
+	u32 stapm_power;
 };
 
 typedef struct soc_amd_stoneyridge_config config_t;