From 68bacc210945ef7d65dd542765c3be997caf7b4d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Michael=20Niew=C3=B6hner?= <foss@mniewoehner.de>
Date: Fri, 24 Sep 2021 23:57:37 +0200
Subject: [PATCH] soc/intel/{skl,cnl,dnv}: disable PM ACPI timer if chosen
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Disable the PM ACPI timer during PMC init, when `USE_PM_ACPI_TIMER` is
disabled. This is done to bring SKL, CNL, DNV in line with the other
platforms, in order to transition handling of the PM timer from FSP to
coreboot in the follow-up changes.

For SKL and CNL, this temporarly redundantly disables the PM Timer,
since FSP does that, too. This redundancy is resolved in the follow-up.

Change-Id: I47280cd670a96c8fa5af107986496234f04e1f77
Signed-off-by: Michael Niewöhner <foss@mniewoehner.de>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/57932
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Nico Huber <nico.h@gmx.de>
---
 src/soc/intel/cannonlake/pmc.c               |  9 +++++++++
 src/soc/intel/denverton_ns/Kconfig           |  1 +
 src/soc/intel/denverton_ns/include/soc/pmc.h |  2 ++
 src/soc/intel/denverton_ns/pmc.c             | 11 +++++++++++
 src/soc/intel/skylake/pmc.c                  |  9 +++++++++
 5 files changed, 32 insertions(+)

diff --git a/src/soc/intel/cannonlake/pmc.c b/src/soc/intel/cannonlake/pmc.c
index d502e0675a..4c88685d04 100644
--- a/src/soc/intel/cannonlake/pmc.c
+++ b/src/soc/intel/cannonlake/pmc.c
@@ -118,6 +118,15 @@ static void soc_pmc_init(struct device *dev)
 	 * found.
 	 */
 	pmc_set_acpi_mode();
+
+	/*
+	 * Disable ACPI PM timer based on Kconfig
+	 *
+	 * Disabling ACPI PM timer is necessary for XTAL OSC shutdown.
+	 * Disabling ACPI PM timer also switches off TCO.
+	 */
+	if (!CONFIG(USE_PM_ACPI_TIMER))
+		setbits8(pmc_mmio_regs() + PCH_PWRM_ACPI_TMR_CTL, ACPI_TIM_DIS);
 }
 
 static void pmc_fill_ssdt(const struct device *dev)
diff --git a/src/soc/intel/denverton_ns/Kconfig b/src/soc/intel/denverton_ns/Kconfig
index a578a71fd0..a8ed92be28 100644
--- a/src/soc/intel/denverton_ns/Kconfig
+++ b/src/soc/intel/denverton_ns/Kconfig
@@ -25,6 +25,7 @@ config CPU_SPECIFIC_OPTIONS
 	select HAVE_SMI_HANDLER
 	select CACHE_MRC_SETTINGS
 	select PCR_COMMON_IOSF_1_0
+	select PM_ACPI_TIMER_OPTIONAL
 	select SUPPORT_CPU_UCODE_IN_CBFS
 	select INTEL_DESCRIPTOR_MODE_CAPABLE
 	select SOC_INTEL_COMMON_BLOCK
diff --git a/src/soc/intel/denverton_ns/include/soc/pmc.h b/src/soc/intel/denverton_ns/include/soc/pmc.h
index fdb1028f1f..0ba24fcb2f 100644
--- a/src/soc/intel/denverton_ns/include/soc/pmc.h
+++ b/src/soc/intel/denverton_ns/include/soc/pmc.h
@@ -240,6 +240,8 @@
 #define GPIO_GPE_CFG		0x120
 #define  GPE0_DWX_MASK		0x7
 #define GPE0_DW_SHIFT(x)	(4 + 4*(x))
+#define PCH_PWRM_ACPI_TMR_CTL	0xfc
+#define  ACPI_TIM_DIS		(1 << 1)
 
 /* I/O ports */
 #define RST_CNT 0xcf9
diff --git a/src/soc/intel/denverton_ns/pmc.c b/src/soc/intel/denverton_ns/pmc.c
index d75f7f05a6..2c208d2aa5 100644
--- a/src/soc/intel/denverton_ns/pmc.c
+++ b/src/soc/intel/denverton_ns/pmc.c
@@ -4,6 +4,7 @@
 #include <device/pci_ops.h>
 #include <console/console.h>
 #include <device/device.h>
+#include <device/mmio.h>
 #include <device/pci.h>
 #include <device/pci_ids.h>
 
@@ -46,6 +47,16 @@ static void pmc_init(struct device *dev)
 
 	/* Configure ACPI mode. */
 	pch_set_acpi_mode();
+
+	/*
+	 * Disable ACPI PM timer based on Kconfig
+	 *
+	 * Disabling ACPI PM timer is necessary for XTAL OSC shutdown.
+	 * Disabling ACPI PM timer also switches off TCO.
+	 */
+	if (!CONFIG(USE_PM_ACPI_TIMER))
+		setbits8((volatile void *)(uintptr_t)(pwrm_base + PCH_PWRM_ACPI_TMR_CTL),
+			 ACPI_TIM_DIS);
 }
 
 static void pci_pmc_read_resources(struct device *dev)
diff --git a/src/soc/intel/skylake/pmc.c b/src/soc/intel/skylake/pmc.c
index c2e724f353..b9b85c2e8f 100644
--- a/src/soc/intel/skylake/pmc.c
+++ b/src/soc/intel/skylake/pmc.c
@@ -101,6 +101,15 @@ void pmc_soc_init(struct device *dev)
 	pci_or_config32(dev, GEN_PMCON_B, 0);
 	setbits32(pwrmbase + GBLRST_CAUSE0, 0);
 	setbits32(pwrmbase + GBLRST_CAUSE1, 0);
+
+	/*
+	 * Disable ACPI PM timer based on Kconfig
+	 *
+	 * Disabling ACPI PM timer is necessary for XTAL OSC shutdown.
+	 * Disabling ACPI PM timer also switches off TCO.
+	 */
+	if (!CONFIG(USE_PM_ACPI_TIMER))
+		setbits8(pmc_mmio_regs() + PCH_PWRM_ACPI_TMR_CTL, ACPI_TIM_DIS);
 }
 
 static void pm1_enable_pwrbtn_smi(void *unused)