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authorLijian Zhao <lijian.zhao@intel.com>2018-10-05 10:31:11 -0700
committerPatrick Georgi <pgeorgi@google.com>2018-10-26 11:20:00 +0000
commit0f5d7b9daf3b2c7a2991c62580c9db9c3e8ac953 (patch)
tree08f09ecf8980eaf664f24501d54b91df26127ec8
parentc308554c10a33c977657b627c880cde60a590eb4 (diff)
downloadcoreboot-0f5d7b9daf3b2c7a2991c62580c9db9c3e8ac953.tar.xz
soc/intel/cannonlake: Add back PM TIMER EMULATION
ACPI PM timer emulation will be added back as default FSP stops TCO count for power saving, which will also stop ACPI PM timer within PCH. CPU PM TIMER EMULATION will help UEFI payload pass, instead of endless loop wait for ACPI PM timer counter to increase. BUG=N/A TEST=Build and boot up fine with whiskey lake rvp board into UEFI shell. Change-Id: Ie069e815e6244c3f85fabf51e186311621d316fd Signed-off-by: Lijian Zhao <lijian.zhao@intel.com> Reviewed-on: https://review.coreboot.org/28937 Reviewed-by: Furquan Shaikh <furquan@google.com> Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
-rw-r--r--src/soc/intel/cannonlake/cpu.c26
-rw-r--r--src/soc/intel/cannonlake/include/soc/cpu.h3
-rw-r--r--src/soc/intel/common/block/include/intelblocks/msr.h1
3 files changed, 29 insertions, 1 deletions
diff --git a/src/soc/intel/cannonlake/cpu.c b/src/soc/intel/cannonlake/cpu.c
index 1fdaf69241..ccd1deaeff 100644
--- a/src/soc/intel/cannonlake/cpu.c
+++ b/src/soc/intel/cannonlake/cpu.c
@@ -1,7 +1,7 @@
/*
* This file is part of the coreboot project.
*
- * Copyright (C) 2017 Intel Corporation.
+ * Copyright (C) 2017-2018 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
@@ -166,6 +166,27 @@ static void configure_c_states(void)
wrmsr(MSR_C_STATE_LATENCY_CONTROL_5, msr);
}
+/*
+ * The emulated ACPI timer allows replacing of the ACPI timer
+ * (PM1_TMR) to have no impart on the system.
+ */
+static void enable_pm_timer_emulation(void)
+{
+ /* ACPI PM timer emulation */
+ msr_t msr;
+ /*
+ * The derived frequency is calculated as follows:
+ * (CTC_FREQ * msr[63:32]) >> 32 = target frequency.
+ * Back solve the multiplier so the 3.579545MHz ACPI timer
+ * frequency is used.
+ */
+ msr.hi = (3579545ULL << 32) / CTC_FREQ;
+ /* Set PM1 timer IO port and enable*/
+ msr.lo = (EMULATE_DELAY_VALUE << EMULATE_DELAY_OFFSET_VALUE) |
+ EMULATE_PM_TMR_EN | (ACPI_BASE_ADDRESS + PM1_TMR);
+ wrmsr(MSR_EMULATE_PM_TMR, msr);
+}
+
/* All CPUs including BSP will run the following function. */
void soc_core_init(struct device *cpu)
{
@@ -188,6 +209,9 @@ void soc_core_init(struct device *cpu)
/* Configure Intel Speed Shift */
configure_isst();
+ /* Enable ACPI Timer Emulation via MSR 0x121 */
+ enable_pm_timer_emulation();
+
/* Enable Direct Cache Access */
configure_dca_cap();
diff --git a/src/soc/intel/cannonlake/include/soc/cpu.h b/src/soc/intel/cannonlake/include/soc/cpu.h
index dfc7183910..1e3e2b4cb1 100644
--- a/src/soc/intel/cannonlake/include/soc/cpu.h
+++ b/src/soc/intel/cannonlake/include/soc/cpu.h
@@ -37,6 +37,9 @@
#define C9_POWER 0xc8
#define C10_POWER 0xc8
+/* Common Timer Copy (CTC) frequency - 24MHz. */
+#define CTC_FREQ 24000000
+
#define C_STATE_LATENCY_MICRO_SECONDS(limit, base) \
(((1 << ((base)*5)) * (limit)) / 1000)
#define C_STATE_LATENCY_FROM_LAT_REG(reg) \
diff --git a/src/soc/intel/common/block/include/intelblocks/msr.h b/src/soc/intel/common/block/include/intelblocks/msr.h
index 63b92013a3..09f0fce1a8 100644
--- a/src/soc/intel/common/block/include/intelblocks/msr.h
+++ b/src/soc/intel/common/block/include/intelblocks/msr.h
@@ -36,6 +36,7 @@
#define MSR_EMULATE_PM_TMR 0x121
#define EMULATE_DELAY_OFFSET_VALUE 20
#define EMULATE_PM_TMR_EN (1 << 16)
+#define EMULATE_DELAY_VALUE 0x13
#define MSR_FEATURE_CONFIG 0x13c
#define FEATURE_CONFIG_RESERVED_MASK 0x3ULL
#define FEATURE_CONFIG_LOCK (1 << 0)