mainboard/variant/puff: set PL values for puff

To be safe for now, don't differentiate between SKUs and use lower
values to ensure board won't be browned out.

BUG=b:143246320
TEST=none
BRANCH=none

Change-Id: I041ebaa33bf2582386198290e625099ba8e2f3c9
Signed-off-by: Kangheui Won <khwon@chromium.org>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/37651
Reviewed-by: Edward O'Callaghan <quasisec@chromium.org>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/mainboard/google/hatch/ramstage.c

@@ -36,6 +36,11 @@ void __weak variant_ramstage_init(void)
 	/* Default weak implementation */
 }
 
+void __weak variant_mainboard_enable(struct device *dev)
+{
+	/* Override mainboard settings per board */
+}
+
 static void mainboard_init(struct device *dev)
 {
 	mainboard_ec_init();
@@ -45,6 +50,7 @@ static void mainboard_enable(struct device *dev)
 {
 	dev->ops->init = mainboard_init;
 	dev->ops->acpi_inject_dsdt_generator = chromeos_dsdt_generator;
+	variant_mainboard_enable(dev);
 }
 
 static void mainboard_chip_init(void *chip_info)

src/mainboard/google/hatch/variants/baseboard/include/baseboard/variants.h

@@ -53,4 +53,7 @@ void variant_devtree_update(void);
 /* Perform variant specific initialization early on in ramstage. */
 void variant_ramstage_init(void);
 
+/* Perform variant specific mainboard initialization */
+void variant_mainboard_enable(struct device *dev);
+
 #endif /* BASEBOARD_VARIANTS_H */

src/mainboard/google/hatch/variants/puff/Makefile.inc

@@ -13,4 +13,5 @@
 ##
 
 ramstage-y += gpio.c
+ramstage-y += mainboard.c
 bootblock-y += gpio.c

src/mainboard/google/hatch/variants/puff/mainboard.c

@@ -0,0 +1,90 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (C) 2019 Google Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <baseboard/variants.h>
+#include <chip.h>
+#include <device/device.h>
+#include <ec/google/chromeec/ec.h>
+
+/*
+ * For type-C chargers, set PL2 to 90% of max power to account for
+ * cable loss and FET Rdson loss in the path from the source.
+ */
+#define SET_PSYSPL2(w)     (9 * (w) / 10)
+
+#define PUFF_PL2   (35)
+
+#define PUFF_PSYSPL2 (58)
+
+#define PUFF_MAX_TIME_WINDOW 6
+#define PUFF_MIN_DUTYCYCLE   4
+
+/*
+ * mainboard_set_power_limits
+ *
+ * Set Pl2 and SysPl2 values based on detected charger.
+ * Values are defined below but we use U22 value for all SKUs for now.
+ * definitions:
+ * x = no value entered. Use default value in parenthesis.
+ *     will set 0 to anything that shouldn't be set.
+ * n = max value of power adapter.
+ * +-------------+-----+---------+-----------+-------+
+ * | sku_id      | PL2 | PsysPL2 |  PsysPL3  |  PL4  |
+ * +-------------+-----+---------+-----------+-------+
+ * | i7 U42      |  51 |   81    | x(.85PL4) | x(82) |
+ * | celeron U22 |  35 |   58    | x(.85PL4) | x(51) |
+ * +-------------+-----+---------+-----------+-------+
+ * For USB C charger:
+ * +-------------+-----+---------+---------+-------+
+ * | Max Power(W)| PL2 | PsysPL2 | PsysPL3 |  PL4  |
+ * +-------------+-----+---------+---------+-------+
+ * | 60 (U42)    |  44 |   54    |    54   |   54  |
+ * | 60 (U22)    |  29 |   54    |    54   | x(43) |
+ * | n  (U42)    |  44 |   .9n   |   .9n   |  .9n  |
+ * | n  (U22)    |  29 |   .9n   |   .9n   | x(43) |
+ * +-------------+-----+---------+---------+-------+
+ */
+static void mainboard_set_power_limits(config_t *conf)
+{
+	enum usb_chg_type type;
+	u32 watts;
+	u32 psyspl2 = PUFF_PSYSPL2; // default barrel jack value for U22
+	int rv = google_chromeec_get_usb_pd_power_info(&type, &watts);
+
+	/* use SoC default value for PsysPL3 and PL4 unless we're on USB-PD*/
+	conf->tdp_psyspl3 = 0;
+	conf->tdp_pl4 = 0;
+
+	if (rv == 0 && type == USB_CHG_TYPE_PD) {
+		/* Detected USB-PD.  Base on max value of adapter */
+		psyspl2 = watts;
+		conf->tdp_psyspl3 = SET_PSYSPL2(psyspl2);
+		/* set max possible time window */
+		conf->tdp_psyspl3_time = PUFF_MAX_TIME_WINDOW;
+		/* set minimum duty cycle */
+		conf->tdp_psyspl3_dutycycle = PUFF_MIN_DUTYCYCLE;
+		conf->tdp_pl4 = SET_PSYSPL2(psyspl2);
+	}
+
+	conf->tdp_pl2_override = PUFF_PL2;
+	/* set psyspl2 to 90% of max adapter power */
+	conf->tdp_psyspl2 = SET_PSYSPL2(psyspl2);
+}
+
+void variant_mainboard_enable(struct device *dev)
+{
+	config_t *conf = config_of_soc();
+	mainboard_set_power_limits(conf);
+}