mb/google/brox: Add support for batteryless booting

Set PsysPL2 and PsysPL3 in addition to making adjustments
to PL2 and PL4 in order to prevent brownouts when we don't
have a battery or have an empty battery at boot time.

BUG=b:335046538,b:329722827
BRANCH=None
TEST=flash
     Able to successfully boot on a SKU1 with 45W, 60W+ adapters
     and SKU2 with a 60W or higher type C adapter.
     30W is still being worked on.

Change-Id: Ie36f16b2c938dce29cd2130a86fc8c08f5ba0902
Signed-off-by: Shelley Chen <shchen@google.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/83087
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Karthik Ramasubramanian <kramasub@google.com>

src/mainboard/google/brox/variants/baseboard/brox/ramstage.c

@@ -5,44 +5,163 @@
 #include <console/console.h>
 #include <device/pci_ops.h>
 #include <drivers/intel/dptf/chip.h>
+#include <ec/google/chromeec/ec.h>
 #include <intelblocks/power_limit.h>
 #include <soc/pci_devs.h>
 
 
 WEAK_DEV_PTR(dptf_policy);
 
+#define SET_PSYSPL2(e, w) ((e) * (w) / 100)
+#define SET_PL2(e, w) ((e - 27) * (w) / 100)
+
+static bool get_sku_index(const struct cpu_power_limits *limits, size_t num_entries,
+					size_t *intel_idx, size_t *brox_idx)
+{
+	uint16_t mchid = pci_s_read_config16(PCI_DEV(0, 0, 0), PCI_DEVICE_ID);
+	u8 tdp = get_cpu_tdp();
+	size_t i = 0;
+
+	for (i = 0; i < ARRAY_SIZE(cpuid_to_adl); i++) {
+		if (mchid == cpuid_to_adl[i].cpu_id && tdp == cpuid_to_adl[i].cpu_tdp) {
+			*intel_idx = cpuid_to_adl[i].limits;
+			break;
+		}
+	}
+
+	if (i == ARRAY_SIZE(cpuid_to_adl)) {
+		printk(BIOS_ERR, "Cannot find correct intel sku index (mchid = %u).\n", mchid);
+		return false;
+	}
+
+	for (i = 0; i < num_entries; i++) {
+		if (mchid == limits[i].mchid && tdp == limits[i].cpu_tdp) {
+			*brox_idx = i;
+			break;
+		}
+	}
+
+	if (i == num_entries) {
+		printk(BIOS_ERR, "Cannot find correct brox sku index (mchid = %u).\n", mchid);
+		return false;
+	}
+
+	return true;
+}
+
 void variant_update_power_limits(const struct cpu_power_limits *limits, size_t num_entries)
 {
+	const struct device *policy_dev;
+	size_t intel_idx, brox_idx;
+	struct drivers_intel_dptf_config *config;
+	struct dptf_power_limits *settings;
+	config_t *conf;
+	struct soc_power_limits_config *soc_config;
+
 	if (!num_entries)
 		return;
 
-	const struct device *policy_dev = DEV_PTR(dptf_policy);
+	policy_dev = DEV_PTR(dptf_policy);
 	if (!policy_dev)
 		return;
 
-	struct drivers_intel_dptf_config *config = policy_dev->chip_info;
+	if (!get_sku_index(limits, num_entries, &intel_idx, &brox_idx))
+		return;
 
-	uint16_t mchid = pci_s_read_config16(PCI_DEV(0, 0, 0), PCI_DEVICE_ID);
+	config = policy_dev->chip_info;
+	settings = &config->controls.power_limits;
+	conf = config_of_soc();
+	soc_config = &conf->power_limits_config[intel_idx];
+	settings->pl1.min_power = limits[brox_idx].pl1_min_power;
+	settings->pl1.max_power = limits[brox_idx].pl1_max_power;
+	settings->pl2.min_power = limits[brox_idx].pl2_min_power;
+	settings->pl2.max_power = limits[brox_idx].pl2_max_power;
 
-	u8 tdp = get_cpu_tdp();
-
-	for (size_t i = 0; i < num_entries; i++) {
-		if (mchid == limits[i].mchid && tdp == limits[i].cpu_tdp) {
-			struct dptf_power_limits *settings = &config->controls.power_limits;
-			config_t *conf = config_of_soc();
-			struct soc_power_limits_config *soc_config = conf->power_limits_config;
-			settings->pl1.min_power = limits[i].pl1_min_power;
-			settings->pl1.max_power = limits[i].pl1_max_power;
-			settings->pl2.min_power = limits[i].pl2_min_power;
-			settings->pl2.max_power = limits[i].pl2_max_power;
-			soc_config->tdp_pl4 = DIV_ROUND_UP(limits[i].pl4_power,
-							   MILLIWATTS_TO_WATTS);
-			printk(BIOS_INFO, "Overriding power limits PL1 (%u, %u) PL2 (%u, %u) PL4 (%u)\n",
-					limits[i].pl1_min_power,
-					limits[i].pl1_max_power,
-					limits[i].pl2_min_power,
-					limits[i].pl2_max_power,
-					limits[i].pl4_power);
-		}
+	if (soc_config->tdp_pl2_override != 0) {
+		settings->pl2.max_power = soc_config->tdp_pl2_override * 1000;
+		settings->pl2.min_power = settings->pl2.max_power;
 	}
+
+	if (soc_config->tdp_pl4 == 0)
+		soc_config->tdp_pl4 = DIV_ROUND_UP(limits[brox_idx].pl4_power,
+						MILLIWATTS_TO_WATTS);
+}
+
+/*
+ * Psys calculations
+ *
+ * We use the following:
+ *
+ * For USB C charger (Max Power):
+ * +-------------+-----+------+---------+-------+
+ * | Max Power(W)| TDP | PL2  | PsysPL2 | PL3/4 |
+ * +-------------+-----+------+---------+-------+
+ * |     30      |  15 |  17  |   25    |  25   | <--- not working yet
+ * |     45      |  15 |  26  |   38    |  38   |
+ * |     60      |  15 |  35  |   51    |  51   |
+ * |    110      |  15 |  55  |   94    |  96   |
+ * +-------------+-----+------+---------+-------+
+ */
+void variant_update_psys_power_limits(const struct cpu_power_limits *limits,
+				      const struct system_power_limits *sys_limits,
+				      size_t num_entries,
+				      const struct psys_config *config_psys)
+{
+	struct soc_power_limits_config *soc_config;
+	size_t intel_idx, brox_idx;
+	u16 volts_mv, current_ma;
+	enum usb_chg_type type;
+	u32 pl2;
+	u32 psyspl2 = 0;
+	u32 psyspl3 = 0;
+	u32 pl2_default;
+	config_t *conf;
+	u32 watts = 0;
+	int rv;
+
+	if (!num_entries)
+		return;
+
+	if (!get_sku_index(limits, num_entries, &intel_idx, &brox_idx))
+		return;
+
+	conf = config_of_soc();
+	soc_config = &conf->power_limits_config[intel_idx];
+
+	pl2_default = DIV_ROUND_UP(limits[brox_idx].pl2_max_power, MILLIWATTS_TO_WATTS);
+
+	/* Get AC adapter power */
+	rv = google_chromeec_get_usb_pd_power_info(&type, &current_ma, &volts_mv);
+
+	if (rv == 0 && type == USB_CHG_TYPE_PD) {
+		/* Detected USB-PD. Get max value of adapter */
+		watts = ((u32)current_ma * volts_mv) / 1000000;
+	}
+	/* If battery is present and has enough charge, add discharge rate */
+	if (CONFIG(EC_GOOGLE_CHROMEEC) && google_chromeec_is_battery_present_and_above_critical_threshold()) {
+		watts += 65;
+	}
+
+	/* We did not detect a battery or a Type-C charger */
+	if (watts == 0) {
+		return;
+	}
+
+	/* set psyspl2 to efficiency% of adapter rating */
+	psyspl2 = SET_PSYSPL2(config_psys->efficiency, watts);
+	psyspl3 = psyspl2;
+	if (watts > 60)
+		psyspl3 += 2;
+
+	/* Limit PL2 if the adapter is with lower capability */
+	pl2 = (psyspl2 > pl2_default) ? pl2_default : SET_PL2(config_psys->efficiency, watts);
+
+	/* If PL4 > psyspl3, lower it */
+	if (soc_config->tdp_pl4 > psyspl3)
+		soc_config->tdp_pl4 = psyspl3;
+
+	/* now that we're done calculating, set everything */
+	soc_config->tdp_pl2_override = pl2;
+	soc_config->tdp_psyspl2 = psyspl2;
+	soc_config->tdp_psyspl3 = psyspl3;
 }

src/mainboard/google/brox/variants/brox/overridetree.cb

@@ -133,7 +133,7 @@ chip soc/intel/alderlake
 				register "options.fan.fine_grained_control" = "1"
 				register "options.fan.step_size" = "2"
 
-				device generic 0 on end
+				device generic 0 alias dptf_policy on end
 			end
 		end # DTT
 		device ref igpu on

src/mainboard/google/brox/variants/brox/ramstage.c

@@ -2,17 +2,53 @@
 
 #include <baseboard/variants.h>
 #include <device/pci_ids.h>
+#include <ec/google/chromeec/ec.h>
+#include <intelblocks/power_limit.h>
 
-const struct cpu_power_limits limits[] = {
-	/* SKU_ID, TDP (Watts), pl1_min, pl1_max, pl2_min, pl2_max, pl4 */
-	/* All values are for performance config as per document #686872 */
-	{ PCI_DID_INTEL_RPL_P_ID_1, 45, 18000, 45000, 115000, 115000, 210000 },
-	{ PCI_DID_INTEL_RPL_P_ID_2, 28, 10000, 28000,  64000,  64000, 126000 },
-	{ PCI_DID_INTEL_RPL_P_ID_3, 15,  6000, 15000,  55000,  55000, 114000 },
+/*
+ * SKU_ID, TDP (Watts), pl1_min (milliWatts), pl1_max (milliWatts),
+ * pl2_min (milliWatts), pl2_max (milliWatts), pl4 (milliWatts)
+ * Following values are for performance config as per document #640982
+ */
+
+const struct cpu_power_limits performance_efficient_limits[] = {
+	{
+		.mchid = PCI_DID_INTEL_RPL_P_ID_3,
+		.cpu_tdp = 15,
+		.pl1_min_power = 6000,
+		.pl1_max_power = 15000,
+		.pl2_min_power = 55000,
+		.pl2_max_power = 55000,
+		.pl4_power = 114000
+	},
+	{
+		.mchid = PCI_DID_INTEL_RPL_P_ID_4,
+		.cpu_tdp = 15,
+		.pl1_min_power = 6000,
+		.pl1_max_power = 15000,
+		.pl2_min_power = 55000,
+		.pl2_max_power = 55000,
+		.pl4_power = 114000
+	},
 };
 
-void variant_devtree_update(void)
+const struct system_power_limits sys_limits[] = {
+	/* SKU_ID, TDP (Watts), psys_pl2 (Watts) */
+	{ PCI_DID_INTEL_RPL_P_ID_3, 15, 60 },
+	{ PCI_DID_INTEL_RPL_P_ID_4, 15, 60 },
+};
+
+const struct psys_config psys_config = {
+	.efficiency = 86,
+};
+
+void __weak variant_devtree_update(void)
 {
-	size_t total_entries = ARRAY_SIZE(limits);
-	variant_update_power_limits(limits, total_entries);
+	printk(BIOS_DEBUG, "WEAK: %s/%s called\n", __FILE__, __func__);
+
+	const struct cpu_power_limits *limits = performance_efficient_limits;
+	size_t limits_size = ARRAY_SIZE(performance_efficient_limits);
+
+	variant_update_power_limits(limits, limits_size);
+	variant_update_psys_power_limits(limits, sys_limits, limits_size, &psys_config);
 }