5 files changed, 77 insertions, 1 deletions
diff --git a/src/soc/amd/cezanne/Kconfig b/src/soc/amd/cezanne/Kconfig
index f7f2d6898a..b916e71e15 100644
--- a/src/soc/amd/cezanne/Kconfig
+++ b/src/soc/amd/cezanne/Kconfig
@@ -19,6 +19,7 @@ config SOC_SPECIFIC_OPTIONS
 	select RESET_VECTOR_IN_RAM
 	select SOC_AMD_COMMON
 	select SOC_AMD_COMMON_BLOCK_ACPIMMIO
+	select SOC_AMD_COMMON_BLOCK_AOAC
 	select SOC_AMD_COMMON_BLOCK_BANKED_GPIOS
 	select SOC_AMD_COMMON_BLOCK_NONCAR
 	select SOC_AMD_COMMON_BLOCK_PCI_MMCONF
diff --git a/src/soc/amd/cezanne/Makefile.inc b/src/soc/amd/cezanne/Makefile.inc
index 6a0229cdbc..01dc97e819 100644
--- a/src/soc/amd/cezanne/Makefile.inc
+++ b/src/soc/amd/cezanne/Makefile.inc
@@ -5,7 +5,8 @@ ifeq ($(CONFIG_SOC_AMD_CEZANNE),y)
 subdirs-y += ../../../cpu/x86/mtrr
 
 # Beware that all-y also adds the compilation unit to verstage on PSP
-all-y += config.c
+all-y		+= config.c
+all-y		+= aoac.c
 
 bootblock-y	+= bootblock.c
 bootblock-y	+= early_fch.c
diff --git a/src/soc/amd/cezanne/aoac.c b/src/soc/amd/cezanne/aoac.c
new file mode 100644
index 0000000000..9c58bb5442
--- /dev/null
+++ b/src/soc/amd/cezanne/aoac.c
@@ -0,0 +1,56 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#include <stdint.h>
+#include <amdblocks/acpimmio.h>
+#include <amdblocks/aoac.h>
+#include <soc/southbridge.h>
+#include <delay.h>
+
+#define FCH_AOAC_UART_FOR_CONSOLE \
+		(CONFIG_UART_FOR_CONSOLE == 0 ? FCH_AOAC_DEV_UART0 \
+		: CONFIG_UART_FOR_CONSOLE == 1 ? FCH_AOAC_DEV_UART1 \
+		: -1)
+#if CONFIG(AMD_SOC_CONSOLE_UART) && FCH_AOAC_UART_FOR_CONSOLE == -1
+# error Unsupported UART_FOR_CONSOLE chosen
+#endif
+
+/*
+ * Table of devices that need their AOAC registers enabled and waited
+ * upon (usually about .55 milliseconds). Instead of individual delays
+ * waiting for each device to become available, a single delay will be
+ * executed.  The console UART is handled separately from this table.
+ *
+ * TODO: Find out which I2C controllers we really need to enable here.
+ */
+const static unsigned int aoac_devs[] = {
+	FCH_AOAC_DEV_AMBA,
+	FCH_AOAC_DEV_I2C0,
+	FCH_AOAC_DEV_I2C1,
+	FCH_AOAC_DEV_I2C2,
+	FCH_AOAC_DEV_I2C3,
+	FCH_AOAC_DEV_ESPI,
+};
+
+void wait_for_aoac_enabled(unsigned int dev)
+{
+	while (!is_aoac_device_enabled(dev))
+		udelay(100);
+}
+
+void enable_aoac_devices(void)
+{
+	unsigned int i;
+
+	for (i = 0; i < ARRAY_SIZE(aoac_devs); i++)
+		power_on_aoac_device(aoac_devs[i]);
+
+	if (CONFIG(AMD_SOC_CONSOLE_UART))
+		power_on_aoac_device(FCH_AOAC_UART_FOR_CONSOLE);
+
+	/* Wait for AOAC devices to indicate power and clock OK */
+	for (i = 0; i < ARRAY_SIZE(aoac_devs); i++)
+		wait_for_aoac_enabled(aoac_devs[i]);
+
+	if (CONFIG(AMD_SOC_CONSOLE_UART))
+		wait_for_aoac_enabled(FCH_AOAC_UART_FOR_CONSOLE);
+}
diff --git a/src/soc/amd/cezanne/early_fch.c b/src/soc/amd/cezanne/early_fch.c
index b6681e32e3..37ba4c7a1a 100644
--- a/src/soc/amd/cezanne/early_fch.c
+++ b/src/soc/amd/cezanne/early_fch.c
@@ -13,6 +13,7 @@ void fch_pre_init(void)
 	fch_smbus_init();
 	fch_enable_cf9_io();
 	fch_enable_legacy_io();
+	enable_aoac_devices();
 
 	/*
 	 * On reset Range_0 defaults to enabled. We want to start with a clean
diff --git a/src/soc/amd/cezanne/include/soc/southbridge.h b/src/soc/amd/cezanne/include/soc/southbridge.h
index 7fb61b67e2..2a294e96ef 100644
--- a/src/soc/amd/cezanne/include/soc/southbridge.h
+++ b/src/soc/amd/cezanne/include/soc/southbridge.h
@@ -12,9 +12,26 @@
 
 #define FCH_LEGACY_UART_DECODE		(ALINK_AHB_ADDRESS + 0x20) /* 0xfedc0020 */
 
+/* FCH AOAC device offsets for AOAC_DEV_D3_CTL/AOAC_DEV_D3_STATE */
+#define FCH_AOAC_DEV_CLK_GEN		0
+#define FCH_AOAC_DEV_I2C0		5
+#define FCH_AOAC_DEV_I2C1		6
+#define FCH_AOAC_DEV_I2C2		7
+#define FCH_AOAC_DEV_I2C3		8
+#define FCH_AOAC_DEV_I2C4		9
+#define FCH_AOAC_DEV_I2C5		10
+#define FCH_AOAC_DEV_UART0		11
+#define FCH_AOAC_DEV_UART1		12
+#define FCH_AOAC_DEV_UART2		16
+#define FCH_AOAC_DEV_AMBA		17
+#define FCH_AOAC_DEV_UART3		26
+#define FCH_AOAC_DEV_ESPI		27
+
 /* IO 0xf0 NCP Error */
 #define   NCP_WARM_BOOT			(1 << 7) /* Write-once */
 
+void enable_aoac_devices(void);
+void wait_for_aoac_enabled(unsigned int dev);
 void fch_pre_init(void);
 void fch_early_init(void);