soc/amd/picasso: Update TSC and monotonic timer

Picasso's TimeStamp Counter is a new design and different than
Stoney Ridge.  Although advertised as invariant, the ST TSC did
not become so until midway through POST making it an unreliable
source for measuring time.  This is not the case for Picasso.

Remove the Stoney Ridge monotonic timer code and rely on the TSC.

Modify the calculation used in Family 15h of finding the number
of boost states first, and get the frequency directly out of the
Pstate0 register.

Signed-off-by: Marshall Dawson <marshalldawson3rd@gmail.com>
Change-Id: I909743483309279eb8c3bf68852d6082381f0dff
Reviewed-on: https://review.coreboot.org/c/coreboot/+/33765
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Richard Spiegel <richard.spiegel@silverbackltd.com>

4 files changed, 12 insertions, 61 deletions

diff --git a/src/soc/amd/picasso/Kconfig b/src/soc/amd/picasso/Kconfig
index 26b2ec4302..b3ee50c97d 100644
--- a/src/soc/amd/picasso/Kconfig
+++ b/src/soc/amd/picasso/Kconfig
@@ -29,14 +29,15 @@ config CPU_SPECIFIC_OPTIONS
 	select X86_AMD_FIXED_MTRRS
 	select X86_AMD_INIT_SIPI
 	select ACPI_AMD_HARDWARE_SLEEP_VALUES
-	select COLLECT_TIMESTAMPS_NO_TSC
 	select DRIVERS_I2C_DESIGNWARE
 	select GENERIC_GPIO_LIB
-	select GENERIC_UDELAY
 	select IOAPIC
 	select HAVE_USBDEBUG_OPTIONS
 	select SPI_FLASH if HAVE_ACPI_RESUME
+	select TSC_CONSTANT_RATE
+	select TSC_MONOTONIC_TIMER
 	select TSC_SYNC_LFENCE
+	select UDELAY_TSC
 	select COLLECT_TIMESTAMPS
 	select SOC_AMD_PI
 	select SOC_AMD_COMMON
@@ -66,10 +67,6 @@ config VBOOT
 	select VBOOT_VBNV_CMOS
 	select VBOOT_VBNV_CMOS_BACKUP_TO_FLASH
 
-config UDELAY_LAPIC_FIXED_FSB
-	int
-	default 200
-
 config HAVE_BOOTBLOCK
 	bool
 	default n
diff --git a/src/soc/amd/picasso/Makefile.inc b/src/soc/amd/picasso/Makefile.inc
index 67d8904a13..ee9b407c53 100644
--- a/src/soc/amd/picasso/Makefile.inc
+++ b/src/soc/amd/picasso/Makefile.inc
@@ -40,7 +40,6 @@ subdirs-y += ../../../cpu/x86/smm
 romstage-y += i2c.c
 romstage-y += romstage.c
 romstage-y += gpio.c
-romstage-y += monotonic_timer.c
 romstage-y += pmutil.c
 romstage-y += reset.c
 romstage-y += smbus.c
@@ -53,7 +52,6 @@ romstage-$(CONFIG_HAVE_SMI_HANDLER) += smi_util.c
 
 verstage-y += gpio.c
 verstage-y += i2c.c
-verstage-y += monotonic_timer.c
 verstage-y += pmutil.c
 verstage-y += reset.c
 verstage-$(CONFIG_PICASSO_UART) += uart.c
@@ -72,7 +70,6 @@ ramstage-y += cpu.c
 ramstage-y += mca.c
 ramstage-$(CONFIG_HAVE_ACPI_TABLES) += acpi.c
 ramstage-y += gpio.c
-ramstage-y += monotonic_timer.c
 ramstage-y += southbridge.c
 ramstage-y += northbridge.c
 ramstage-y += pmutil.c
@@ -89,7 +86,6 @@ ramstage-y += tsc_freq.c
 ramstage-$(CONFIG_SPI_FLASH) += spi.c
 ramstage-y += finalize.c
 
-smm-y += monotonic_timer.c
 smm-y += smihandler.c
 smm-y += smi_util.c
 smm-y += tsc_freq.c
diff --git a/src/soc/amd/picasso/monotonic_timer.c b/src/soc/amd/picasso/monotonic_timer.c
deleted file mode 100644
index 7ea571f635..0000000000
--- a/src/soc/amd/picasso/monotonic_timer.c
+++ /dev/null
@@ -1,38 +0,0 @@
-/*
- * This file is part of the coreboot project.
- *
- * Copyright 2018 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; either 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 <cpu/x86/msr.h>
-#include <timer.h>
-#include <timestamp.h>
-
-#define CU_PTSC_MSR	0xc0010280
-#define PTSC_FREQ_MHZ	100
-
-void timer_monotonic_get(struct mono_time *mt)
-{
-	mono_time_set_usecs(mt, timestamp_get());
-}
-
-uint64_t timestamp_get(void)
-{
-	unsigned long long val;
-	msr_t msr;
-
-	msr = rdmsr(CU_PTSC_MSR);
-
-	val = ((unsigned long long)msr.hi << 32) | msr.lo;
-
-	return val / PTSC_FREQ_MHZ;
-}
diff --git a/src/soc/amd/picasso/tsc_freq.c b/src/soc/amd/picasso/tsc_freq.c
index 29121b955e..6167726955 100644
--- a/src/soc/amd/picasso/tsc_freq.c
+++ b/src/soc/amd/picasso/tsc_freq.c
@@ -19,31 +19,27 @@
 #include <cpu/amd/msr.h>
 #include <cpu/x86/tsc.h>
 #include <console/console.h>
-#include <soc/pci_devs.h>
-#include <device/pci_ops.h>
+
+static unsigned long mhz;
 
 unsigned long tsc_freq_mhz(void)
 {
 	msr_t msr;
 	uint8_t cpufid;
 	uint8_t cpudid;
-	uint8_t boost_states;
+	uint8_t high_state;
 
-	/*
-	 * See the Family 15h Models 70h-7Fh BKDG (PID 55072) definition for
-	 * MSR0000_0010.  The TSC increments at the P0 frequency. According
-	 * to the "Software P-state Numbering" section, P0 is the highest
-	 * non-boosted state.  freq = 100MHz * (CpuFid + 10h) / (2^(CpuDid)).
-	 */
-	boost_states = (pci_read_config32(SOC_PM_DEV, CORE_PERF_BOOST_CTRL)
-			>> 2) & 0x7;
+	if (mhz)
+		return mhz;
 
-	msr = rdmsr(PSTATE_0_MSR + boost_states);
+	high_state = rdmsr(PS_LIM_REG).lo & 0x7;
+	msr = rdmsr(PSTATE_0_MSR + high_state);
 	if (!(msr.hi & 0x80000000))
 		die("Unknown error: cannot determine P-state 0\n");
 
 	cpufid = (msr.lo & 0x3f);
 	cpudid = (msr.lo & 0x1c0) >> 6;
 
-	return (100 * (cpufid + 0x10)) / (0x01 << cpudid);
+	mhz = (100 * (cpufid + 0x10)) / (0x01 << cpudid);
+	return mhz;
 }