soc/intel/common: Add common code for acpi c/p/t-state entries

Change-Id: I87505bb31cd1b46d27cc5c9ba8d086df7393653e
Signed-off-by: Hannah Williams <hannah.williams@intel.com>
Reviewed-on: https://review.coreboot.org/15050
Tested-by: build bot (Jenkins)
Reviewed-by: Aaron Durbin <adurbin@chromium.org>

1 files changed, 302 insertions, 0 deletions

diff --git a/src/soc/intel/common/acpi/acpi.c b/src/soc/intel/common/acpi/acpi.c
new file mode 100644
index 0000000000..3866e68e9a
--- /dev/null
+++ b/src/soc/intel/common/acpi/acpi.c
@@ -0,0 +1,302 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (C) 2016 Intel Corporation.
+ *
+ * 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; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * 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 <arch/acpi.h>
+#include <arch/acpigen.h>
+#include <arch/cpu.h>
+#include <cpu/intel/turbo.h>
+#include <cpu/x86/msr.h>
+#include <soc/intel/common/acpi.h>
+#include <soc/pm.h>
+
+#define MSR_PLATFORM_INFO		0xce
+#define MSR_TURBO_RATIO_LIMIT		0x1ad
+#define MSR_CONFIG_TDP_NOMINAL		0x648
+#define MSR_RAPL_POWER_UNIT		0x606
+#define MSR_PKG_POWER_INFO		0x614
+
+/* P-state configuration */
+#define PSS_MAX_ENTRIES			8
+#define PSS_RATIO_STEP			2
+#define PSS_LATENCY_TRANSITION		10
+#define PSS_LATENCY_BUSMASTER		10
+
+
+__attribute__((weak)) int cpu_get_coord_type(void)
+{
+	return HW_ALL;
+}
+
+__attribute__((weak)) int cpu_config_tdp_levels(void)
+{
+	return 0;
+}
+
+__attribute__((weak)) uint32_t cpu_get_min_ratio(void)
+{
+	msr_t msr;
+	/* Get bus ratio limits and calculate clock speeds */
+	msr = rdmsr(MSR_PLATFORM_INFO);
+	return ((msr.hi >> 8) & 0xff); /* Max Efficiency Ratio */
+}
+
+__attribute__((weak)) uint32_t cpu_get_max_ratio(void)
+{
+	msr_t msr;
+	uint32_t ratio_max;
+	if (cpu_config_tdp_levels()) {
+		/* Set max ratio to nominal TDP ratio */
+		msr = rdmsr(MSR_CONFIG_TDP_NOMINAL);
+		ratio_max = msr.lo & 0xff;
+	} else {
+		msr = rdmsr(MSR_PLATFORM_INFO);
+		/* Max Non-Turbo Ratio */
+		ratio_max = (msr.lo >> 8) & 0xff;
+	}
+	return ratio_max;
+}
+
+__attribute__((weak)) uint32_t cpu_get_bus_clock(void)
+{
+	/* CPU bus clock is set by default here to 100MHz.
+           This function returns the bus clock in KHz.
+	*/
+	return 100 * KHz;
+}
+
+__attribute__((weak)) uint32_t cpu_get_power_max(void)
+{
+	msr_t msr;
+	int power_unit;
+
+	msr = rdmsr(MSR_RAPL_POWER_UNIT);
+	power_unit = 2 << ((msr.lo & 0xf) - 1);
+	msr = rdmsr(MSR_PKG_POWER_INFO);
+	return ((msr.lo & 0x7fff) / power_unit) * 1000;
+}
+
+__attribute__((weak)) uint32_t cpu_get_max_turbo_ratio(void)
+{
+	msr_t msr;
+	msr = rdmsr(MSR_TURBO_RATIO_LIMIT);
+	return msr.lo & 0xff;
+}
+
+__attribute__((weak)) acpi_cstate_t *soc_get_cstate_map(int *entries)
+{
+	*entries = 0;
+	return NULL;
+}
+
+__attribute__((weak)) acpi_tstate_t *soc_get_tss_table(int *entries)
+{
+	*entries = 0;
+	return NULL;
+}
+
+__attribute__((weak)) uint16_t soc_get_acpi_base_address(void)
+{
+#define ACPI_BASE_ADDR 0x400
+	return (ACPI_BASE_ADDR);
+}
+
+static int calculate_power(int tdp, int p1_ratio, int ratio)
+{
+	u32 m;
+	u32 power;
+
+	/*
+	 * M = ((1.1 - ((p1_ratio - ratio) * 0.00625)) / 1.1) ^ 2
+	 *
+	 * Power = (ratio / p1_ratio) * m * tdp
+	 */
+
+	m = (110000 - ((p1_ratio - ratio) * 625)) / 11;
+	m = (m * m) / 1000;
+
+	power = ((ratio * 100000 / p1_ratio) / 100);
+	power *= (m / 100) * (tdp / 1000);
+	power /= 1000;
+	return power;
+}
+
+static int get_cores_per_package(void)
+{
+	struct cpuinfo_x86 c;
+	struct cpuid_result result;
+	int cores = 1;
+
+	get_fms(&c, cpuid_eax(1));
+	if (c.x86 != 6)
+		return 1;
+
+	result = cpuid_ext(0xb, 1);
+	cores = result.ebx & 0xff;
+
+	return cores;
+}
+
+static void generate_p_state_entries(int core, int cores_per_package)
+{
+	int ratio_min, ratio_max, ratio_turbo, ratio_step;
+	int coord_type, power_max, num_entries;
+	int ratio, power, clock, clock_max;
+
+	coord_type = cpu_get_coord_type();
+	ratio_min = cpu_get_min_ratio();
+	ratio_max = cpu_get_max_ratio();
+	clock_max = (ratio_max * cpu_get_bus_clock()) / KHz;
+
+	/* Calculate CPU TDP in mW */
+	power_max = cpu_get_power_max();
+
+        /* Write _PCT indicating use of FFixedHW */
+	acpigen_write_empty_PCT();
+
+        /* Write _PPC with no limit on supported P-state */
+	acpigen_write_PPC_NVS();
+       /* Write PSD indicating configured coordination type */
+	acpigen_write_PSD_package(core, 1, coord_type);
+
+        /* Add P-state entries in _PSS table */
+        acpigen_write_name("_PSS");
+
+	/* Determine ratio points */
+	ratio_step = PSS_RATIO_STEP;
+	num_entries = ((ratio_max - ratio_min) / ratio_step) + 1;
+	if (num_entries > PSS_MAX_ENTRIES) {
+		ratio_step += 1;
+		num_entries = ((ratio_max - ratio_min) / ratio_step) + 1;
+	}
+
+	/* P[T] is Turbo state if enabled */
+	if (get_turbo_state() == TURBO_ENABLED) {
+	/* _PSS package count including Turbo */
+		acpigen_write_package(num_entries + 2);
+		ratio_turbo = cpu_get_max_turbo_ratio();
+
+		/* Add entry for Turbo ratio */
+		acpigen_write_PSS_package(
+			clock_max + 1,          /* MHz */
+			power_max,              /* mW */
+			PSS_LATENCY_TRANSITION, /* lat1 */
+			PSS_LATENCY_BUSMASTER,  /* lat2 */
+			ratio_turbo << 8,       /* control */
+			ratio_turbo << 8);      /* status */
+	} else {
+		/* _PSS package count without Turbo */
+		acpigen_write_package(num_entries + 1);
+	}
+
+	/* First regular entry is max non-turbo ratio */
+	acpigen_write_PSS_package(
+		clock_max,              /* MHz */
+		power_max,              /* mW */
+		PSS_LATENCY_TRANSITION, /* lat1 */
+		PSS_LATENCY_BUSMASTER,  /* lat2 */
+		ratio_max << 8,         /* control */
+		ratio_max << 8);        /* status */
+
+	/* Generate the remaining entries */
+	for (ratio = ratio_min + ((num_entries - 1) * ratio_step);
+		ratio >= ratio_min; ratio -= ratio_step) {
+
+	/* Calculate power at this ratio */
+		power = calculate_power(power_max, ratio_max, ratio);
+		clock = (ratio * cpu_get_bus_clock()) / KHz;
+
+		acpigen_write_PSS_package(
+			clock,                  /* MHz */
+			power,                  /* mW */
+			PSS_LATENCY_TRANSITION, /* lat1 */
+			PSS_LATENCY_BUSMASTER,  /* lat2 */
+			ratio << 8,             /* control */
+			ratio << 8);            /* status */
+	}
+	/* Fix package length */
+	acpigen_pop_len();
+}
+
+static void generate_c_state_entries(void)
+{
+	acpi_cstate_t *c_state_map;
+	int entries;
+
+	c_state_map = soc_get_cstate_map(&entries);
+
+	/* Generate C-state tables */
+	acpigen_write_CST_package(c_state_map, entries);
+}
+
+static void generate_t_state_entries(int core, int cores_per_package)
+{
+	acpi_tstate_t *soc_tss_table;
+	int entries;
+
+	soc_tss_table = soc_get_tss_table(&entries);
+	if (entries == 0)
+		return;
+
+	/* Indicate SW_ALL coordination for T-states */
+	acpigen_write_TSD_package(core, cores_per_package, SW_ALL);
+
+	/* Indicate FFixedHW so OS will use MSR */
+	acpigen_write_empty_PTC();
+
+	/* Set NVS controlled T-state limit */
+	acpigen_write_TPC("\\TLVL");
+
+	/* Write TSS table for MSR access */
+	acpigen_write_TSS_package(entries, soc_tss_table);
+}
+
+void generate_cpu_entries(device_t device)
+{
+	int core_id, cpu_id, pcontrol_blk = soc_get_acpi_base_address();
+	int plen = 6;
+	int totalcores = dev_count_cpu();
+	int cores_per_package = get_cores_per_package();
+	int numcpus = totalcores / cores_per_package;
+
+	printk(BIOS_DEBUG, "Found %d CPU(s) with %d core(s) each.\n",
+		numcpus, cores_per_package);
+
+	for (cpu_id=0; cpu_id < numcpus; cpu_id++) {
+		for (core_id=0; core_id < cores_per_package; core_id++) {
+			if (core_id > 0) {
+				pcontrol_blk = 0;
+				plen = 0;
+			}
+
+			/* Generate processor \_PR.CPUx */
+			acpigen_write_processor(
+				(cpu_id)*cores_per_package + core_id,
+				pcontrol_blk, plen);
+
+			/* Generate P-state tables */
+			generate_p_state_entries(
+				core_id, cores_per_package);
+
+			/* Generate C-state tables */
+			generate_c_state_entries();
+
+			/* Generate T-state tables */
+			generate_t_state_entries(
+				core_id, cores_per_package);
+
+			acpigen_pop_len();
+		}
+	}
+}