soc/amd/cezanne: add AOAC support

Change-Id: I9d7574b60640eaf9a47a797e823324edeaf1e770
Signed-off-by: Felix Held <felix-coreboot@felixheld.de>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/48609
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
Reviewed-by: Marshall Dawson <marshalldawson3rd@gmail.com>

1 files changed, 56 insertions, 0 deletions

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);
+}