Change in coreboot[master]: soc/intel/apollolake: Enable UART debug controller on S3 resume

[Furquan Shaikh (Code Review)]

Furquan Shaikh has uploaded this change for review. ( https://review.coreboot.org/20888

Change subject: soc/intel/apollolake: Enable UART debug controller on S3 resume
......................................................................

soc/intel/apollolake: Enable UART debug controller on S3 resume

1. Add a new variable to GNVS to store information during S3 suspend
whether UART debug controller is enabled.

2. On resume, read stored GNVS variable to decide if UART debug port
controller needs to be initialized.

3. Provide helper functions required by intel/common UARRT driver for
enabling controller on S3 resume.

BUG=b:64030366

Change-Id: Idd17dd0bd3c644383f273b465a16add184e3b171
Signed-off-by: Furquan Shaikh 
---
M src/soc/intel/apollolake/Makefile.inc
M src/soc/intel/apollolake/acpi/globalnvs.asl
M src/soc/intel/apollolake/include/soc/nvs.h
M src/soc/intel/apollolake/uart.c
M src/soc/intel/common/block/smm/smihandler.c
5 files changed, 36 insertions(+), 4 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/88/20888/1

diff --git a/src/soc/intel/apollolake/Makefile.inc b/src/soc/intel/apollolake/Makefile.inc
index 07bbdcd..589b846 100644
--- a/src/soc/intel/apollolake/Makefile.inc
+++ b/src/soc/intel/apollolake/Makefile.inc
@@ -42,6 +42,7 @@
 smm-y += smihandler.c
 smm-y += spi.c
 smm-y += uart_early.c
+smm-y += uart.c

ramstage-$(CONFIG_HAVE_ACPI_TABLES) += acpi.c
 ramstage-y += cpu.c
diff --git a/src/soc/intel/apollolake/acpi/globalnvs.asl b/src/soc/intel/apollolake/acpi/globalnvs.asl
index 1548c30..6431fae 100644
--- a/src/soc/intel/apollolake/acpi/globalnvs.asl
+++ b/src/soc/intel/apollolake/acpi/globalnvs.asl
@@ -41,6 +41,8 @@
    PRT0,	32,     // 0x25 - 0x28 - PERST_0 Address
    SCDP,	8,      // 0x29 - SD_CD GPIO portid
    SCDO,	8,      // 0x2A - GPIO pad offset relative to the community
+	UIOR,	8,      // 0x2B - UART debug controller init on S3 resume
+
    /* ChromeOS stuff (0x100 -> 0xfff, size 0xeff) */
    Offset (0x100),
    #include <vendorcode/google/chromeos/acpi/gnvs.asl>
diff --git a/src/soc/intel/apollolake/include/soc/nvs.h b/src/soc/intel/apollolake/include/soc/nvs.h
index 56085b2..9a09800 100644
--- a/src/soc/intel/apollolake/include/soc/nvs.h
+++ b/src/soc/intel/apollolake/include/soc/nvs.h
@@ -42,7 +42,9 @@
    uint32_t	prt0; /* 0x25 - 0x28 - PERST_0 Address */
    uint8_t		scdp; /* 0x29 - SD_CD GPIO portid */
    uint8_t		scdo; /* 0x2A - GPIO pad offset relative to the community */
-	uint8_t		unused[213];
+	uint8_t		uior; /* 0x2B - UART debug controller init on S3
+					 resume */
+	uint8_t		unused[212];

/* ChromeOS specific (0x100 - 0xfff) */
    chromeos_acpi_t chromeos;
diff --git a/src/soc/intel/apollolake/uart.c b/src/soc/intel/apollolake/uart.c
index 3db460a..14dc5f1 100644
--- a/src/soc/intel/apollolake/uart.c
+++ b/src/soc/intel/apollolake/uart.c
@@ -20,20 +20,44 @@
  * shouldn't cause any fragmentation.
  */

+#include <cbmem.h>
 #include <device/device.h>
 #include <device/pci.h>
 #include <intelblocks/uart.h>
+#include <soc/nvs.h>
 #include <soc/pci_devs.h>

+bool pch_uart_is_debug_controller(struct device *dev)
+{
+	return dev->path.pci.devfn == _PCH_DEVFN(UART,
+						CONFIG_UART_FOR_CONSOLE);
+}
+
+#if ENV_RAMSTAGE
 void pch_uart_read_resources(struct device *dev)
 {
    pci_dev_read_resources(dev);

-	if ((IS_ENABLED(CONFIG_SOC_UART_DEBUG) &&
-	    dev->path.pci.devfn == _PCH_DEVFN(UART,
-						CONFIG_UART_FOR_CONSOLE))) {
+	if (IS_ENABLED(CONFIG_SOC_UART_DEBUG) &&
+		pch_uart_is_debug_controller(dev)) {
    	/* will override existing resource. */
    	fixed_mem_resource(dev, PCI_BASE_ADDRESS_0,
    			CONFIG_CONSOLE_UART_BASE_ADDRESS >> 10, 4, 0);
    }
 }
+#endif
+
+bool pch_uart_init_debug_controller_on_resume(void)
+{
+	global_nvs_t *gnvs = cbmem_find(CBMEM_ID_ACPI_GNVS);
+
+	if (gnvs)
+		return !!gnvs->uior;
+
+	return false;
+}
+
+device_t pch_uart_get_debug_controller(void)
+{
+	return _PCH_DEV(UART, CONFIG_UART_FOR_CONSOLE);
+}
diff --git a/src/soc/intel/common/block/smm/smihandler.c b/src/soc/intel/common/block/smm/smihandler.c
index b620ff9..dde9b1f 100644
--- a/src/soc/intel/common/block/smm/smihandler.c
+++ b/src/soc/intel/common/block/smm/smihandler.c
@@ -22,6 +22,7 @@
 #include <device/pci_def.h>
 #include <elog.h>
 #include <intelblocks/smihandler.h>
+#include <intelblocks/uart.h>
 #include <soc/nvs.h>
 #include <soc/pm.h>
 #include <soc/gpio.h>
@@ -160,6 +161,8 @@
    case ACPI_S3:
    	printk(BIOS_DEBUG, "SMI#: Entering S3 (Suspend-To-RAM)\n");

+		gnvs->uior = uart_debug_controller_is_initialized();
+
    	/* Invalidate the cache before going to S3 */
    	wbinvd();
    	break;