Mushu : Add GPU temperature sensor driver

Add GPU temperature sensor driver in driver/temp_sensor for temperature
read .

BUG=b:148968367
BRANCH=none
TEST=make BOARD=mushu

Change-Id: Ide1613597dbb3712637649c098a7b804370f5e02
Signed-off-by: loganliao <Logan_Liao@compal.corp-partner.google.com>
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/2062117
Reviewed-by: Tim Wawrzynczak <twawrzynczak@chromium.org>
Reviewed-by: Logan Liao <logan_liao@compal.corp-partner.google.com>
Commit-Queue: Logan Liao <logan_liao@compal.corp-partner.google.com>
Tested-by: Logan Liao <logan_liao@compal.corp-partner.google.com>

1 files changed, 76 insertions, 0 deletions

diff --git a/driver/temp_sensor/amd_r19me4070.c b/driver/temp_sensor/amd_r19me4070.c
new file mode 100644
index 0000000000..5da1129052
--- /dev/null
+++ b/driver/temp_sensor/amd_r19me4070.c
@@ -0,0 +1,76 @@
+/* Copyright 2020 The Chromium OS Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+/* R19ME4070 temperature sensor module for Chrome EC */
+
+#include "chipset.h"
+#include "common.h"
+#include "console.h"
+#include "hooks.h"
+#include "i2c.h"
+#include "amd_r19me4070.h"
+
+#define CPRINTS(format, args...) cprints(CC_USBCHARGE, format, ## args)
+#define CPRINTF(format, args...) cprintf(CC_USBCHARGE, format, ## args)
+
+/* GPU I2C address */
+#define GPU_ADDR_FLAGS                  0x82
+
+/*
+ * Tell SMBus slave which register to read before GPU read
+ * temperature, call it "GPU INIT".
+ */
+#define GPU_INIT_OFFSET                 0x01
+#define GPU_TEMPERATURE_OFFSET          0x03
+#define GPU_INIT_WRITE_VALUE            0x0F01665A
+
+static int initialized;
+
+static int read_gpu_temp(int *temp)
+{
+	return i2c_read32(I2C_PORT_GPU, GPU_ADDR_FLAGS, GPU_TEMPERATURE_OFFSET,
+			  temp);
+}
+
+static void gpu_init_temp_sensor(void)
+{
+	int rv;
+
+	rv = i2c_write32(I2C_PORT_GPU, GPU_ADDR_FLAGS, GPU_INIT_OFFSET,
+			  GPU_INIT_WRITE_VALUE);
+	if (rv == EC_SUCCESS) {
+		initialized = 1;
+		return;
+	}
+	CPRINTS("init GPU fail");
+}
+DECLARE_HOOK(HOOK_INIT, gpu_init_temp_sensor, HOOK_PRIO_INIT_I2C + 1);
+
+/* INIT GPU first before read the GPU's die tmeperature. */
+int get_temp_R19ME4070(int idx, int *temp_ptr)
+{
+	int reg, rv;
+
+	/* if no INIT GPU, must init it first and wait 1 sec. */
+	if (!initialized) {
+		gpu_init_temp_sensor();
+		return EC_ERROR_BUSY;
+	}
+	rv = read_gpu_temp(&reg);
+	if (rv) {
+		CPRINTS("read GPU Temperature fail");
+		return rv;
+	}
+	/*
+	 * The register is four bytes, bit[17:9] represents the GPU temperature.
+	 * 0x000 : 0	ﾟC
+	 * 0x001 : 1	ﾟC
+	 * 0x002 : 2	ﾟC
+	 * ...
+	 * 0x1FF : 511	ﾟC
+	 */
+	*temp_ptr = C_TO_K((reg >> 9) & (0x1ff));
+	return EC_SUCCESS;
+}