drivers: bbram: Add it8xxx2 BBRAM driver implementation

Note that the it8xxx2 does not support a status register so that
functionality is omitted.

This change also adds driver tests that build both the npcx and it8xxx2
drivers.

Signed-off-by: Yuval Peress <peress@chromium.org>

drivers/bbram/CMakeLists.txt

@@ -4,4 +4,5 @@
 zephyr_library()
 
 zephyr_library_sources_ifdef(CONFIG_BBRAM_NPCX bbram_npcx.c)
+zephyr_library_sources_ifdef(CONFIG_BBRAM_IT8XXX2 bbram_it8xxx2.c)
 zephyr_library_sources_ifdef(CONFIG_BBRAM_EMUL bbram_emul.c)

drivers/bbram/Kconfig

@@ -20,6 +20,8 @@ config BBRAM_INIT_PRIORITY
 
 source "drivers/bbram/Kconfig.npcx"
 
+source "drivers/bbram/Kconfig.it8xxx2"
+
 source "drivers/bbram/Kconfig.bbram_emul"
 
 endif # BBRAM

drivers/bbram/Kconfig.it8xxx2

@@ -0,0 +1,12 @@
+# Copyright (c) 2021 Google Inc
+# SPDX-License-Identifier: Apache-2.0
+
+DT_COMPAT_ST_BBRAM_IT8XXX2 := ite,it8xxx2-bbram
+
+config BBRAM_IT8XXX2
+	bool "ITE IT81202 Battery-backed RAM drivers"
+	depends on SOC_FAMILY_RISCV_ITE
+	default $(dt_compat_enabled,${DT_COMPAT_ST_BBRAM_IT8XXX2})
+	help
+	  This option enables the BBRAM driver for RISCV_ITE family of
+	  processors.

drivers/bbram/bbram_it8xxx2.c

@@ -0,0 +1,70 @@
+/*
+ * Copyright (c) 2021 Google Inc
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#define DT_DRV_COMPAT ite_it8xxx2_bbram
+
+#include <drivers/bbram.h>
+#include <errno.h>
+#include <sys/util.h>
+
+#include <logging/log.h>
+LOG_MODULE_REGISTER(bbram, CONFIG_BBRAM_LOG_LEVEL);
+
+/** Device config */
+struct bbram_it8xxx2_config {
+	/** BBRAM base address */
+	uintptr_t base_addr;
+	/** BBRAM size (Unit:bytes) */
+	int size;
+};
+
+static int bbram_it8xxx2_read(const struct device *dev, size_t offset, size_t size, uint8_t *data)
+{
+	const struct bbram_it8xxx2_config *config = dev->config;
+
+	if (size < 1 || offset + size > config->size) {
+		return -EFAULT;
+	}
+
+	bytecpy(data, ((uint8_t *)config->base_addr + offset), size);
+	return 0;
+}
+
+static int bbram_it8xxx2_write(const struct device *dev, size_t offset, size_t size,
+			       const uint8_t *data)
+{
+	const struct bbram_it8xxx2_config *config = dev->config;
+
+	if (size < 1 || offset + size > config->size) {
+		return -EFAULT;
+	}
+
+	bytecpy(((uint8_t *)config->base_addr + offset), data, size);
+	return 0;
+}
+
+static const struct bbram_driver_api bbram_it8xxx2_driver_api = {
+	.read = bbram_it8xxx2_read,
+	.write = bbram_it8xxx2_write,
+};
+
+static int bbram_it8xxx2_init(const struct device *dev)
+{
+	ARG_UNUSED(dev);
+
+	return 0;
+}
+
+#define BBRAM_INIT(inst)                                                                           \
+	static const struct bbram_it8xxx2_config bbram_cfg_##inst = {                              \
+		.base_addr = DT_INST_REG_ADDR(inst),                                               \
+		.size = DT_INST_REG_SIZE(inst),                                                    \
+	};                                                                                         \
+	DEVICE_DT_INST_DEFINE(inst, bbram_it8xxx2_init, NULL, NULL, &bbram_cfg_##inst,             \
+			      PRE_KERNEL_1, CONFIG_BBRAM_INIT_PRIORITY,                            \
+			      &bbram_it8xxx2_driver_api);
+
+DT_INST_FOREACH_STATUS_OKAY(BBRAM_INIT);

dts/bindings/memory-controllers/ite,it8xxx2-bbram.yaml

@@ -0,0 +1,15 @@
+# Copyright (c) 2021 Google Inc.
+# SPDX-License-Identifier: Apache-2.0
+
+description: ITE, IT8XXX2 Battery Backed RAM node
+
+compatible: "ite,it8xxx2-bbram"
+
+include: base.yaml
+
+properties:
+    reg:
+        required: true
+
+    label:
+        required: true

dts/riscv/it8xxx2.dtsi

@@ -32,6 +32,14 @@
 		#size-cells = <1>;
 		ranges;
 
+		bbram: bb-ram@f02200 {
+			#address-cells = <1>;
+			#size-cells = <1>;
+			compatible = "ite,it8xxx2-bbram";
+			status = "okay";
+			reg = <0x00f02200 0xc0>;
+			label = "BBRAM";
+		};
 		flashctrl: flash-controller@f01000 {
 			compatible = "ite,it8xxx2-flash-controller";
 			reg = <0x00f01000 0x100>;

tests/drivers/bbram/boards/qemu_riscv32.overlay

@@ -0,0 +1,14 @@
+/*
+ * Copyright 2021 Google LLC
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+/ {
+	bbram: bbram@80 {
+		compatible = "ite,it8xxx2-bbram";
+		status = "okay";
+		reg = <0x80 0xff>;
+		label = "BBRAM";
+	};
+};

tests/drivers/bbram/emul/CMakeLists.txt

@@ -0,0 +1,10 @@
+# Copyright 2021 Google LLC
+# SPDX-License-Identifier: Apache-2.0
+
+cmake_minimum_required(VERSION 3.20.0)
+
+find_package(Zephyr REQUIRED HINTS $ENV{ZEPHYR_BASE})
+project(bbram)
+
+FILE(GLOB app_sources src/*.c)
+target_sources(app PRIVATE ${app_sources})

tests/drivers/bbram/emul/src/main.c

@@ -0,0 +1,125 @@
+/*
+ * Copyright 2021 Google LLC
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include <device.h>
+#include <drivers/bbram.h>
+#include <string.h>
+#include <ztest.h>
+
+#define BBRAM_NODELABEL DT_NODELABEL(bbram)
+#define BBRAM_LABEL DT_LABEL(BBRAM_NODELABEL)
+#define BBRAM_SIZE DT_PROP(BBRAM_NODELABEL, size)
+
+static void test_get_size(void)
+{
+	const struct device *dev = device_get_binding(BBRAM_LABEL);
+	size_t size;
+
+	zassert_ok(bbram_get_size(dev, &size), NULL);
+	zassert_equal(size, BBRAM_SIZE, NULL);
+}
+
+static void test_bbram_out_of_bounds(void)
+{
+	const struct device *dev = device_get_binding(BBRAM_LABEL);
+	uint8_t buffer[BBRAM_SIZE];
+
+	zassert_not_null(dev, NULL);
+	zassert_equal(bbram_read(dev, 0, 0, buffer), -EFAULT, NULL);
+	zassert_equal(bbram_read(dev, 0, BBRAM_SIZE + 1, buffer), -EFAULT, NULL);
+	zassert_equal(bbram_read(dev, BBRAM_SIZE - 1, 2, buffer), -EFAULT, NULL);
+	zassert_equal(bbram_write(dev, 0, 0, buffer), -EFAULT, NULL);
+	zassert_equal(bbram_write(dev, 0, BBRAM_SIZE + 1, buffer), -EFAULT, NULL);
+	zassert_equal(bbram_write(dev, BBRAM_SIZE - 1, 2, buffer), -EFAULT, NULL);
+}
+
+static void test_read_write(void)
+{
+	const struct device *dev = device_get_binding(BBRAM_LABEL);
+	uint8_t buffer[BBRAM_SIZE];
+	uint8_t expected[BBRAM_SIZE];
+
+	for (int i = 0; i < BBRAM_SIZE; ++i) {
+		expected[i] = i;
+	}
+	/* Set and verify content. */
+	zassert_ok(bbram_write(dev, 0, BBRAM_SIZE, expected), NULL);
+	zassert_ok(bbram_read(dev, 0, BBRAM_SIZE, buffer), NULL);
+	zassert_mem_equal(buffer, expected, BBRAM_SIZE, NULL);
+}
+
+static void test_set_invalid(void)
+{
+	const struct device *dev = device_get_binding(BBRAM_LABEL);
+
+	zassert_equal(bbram_check_invalid(dev), 0, NULL);
+	zassert_ok(bbram_emul_set_invalid(dev, true), NULL);
+	zassert_equal(bbram_check_invalid(dev), 1, NULL);
+	zassert_equal(bbram_check_invalid(dev), 0, NULL);
+}
+
+static void test_set_standby(void)
+{
+	const struct device *dev = device_get_binding(BBRAM_LABEL);
+
+	zassert_equal(bbram_check_standby_power(dev), 0, NULL);
+	zassert_ok(bbram_emul_set_standby_power_state(dev, true), NULL);
+	zassert_equal(bbram_check_standby_power(dev), 1, NULL);
+	zassert_equal(bbram_check_standby_power(dev), 0, NULL);
+}
+
+static void test_set_power(void)
+{
+	const struct device *dev = device_get_binding(BBRAM_LABEL);
+
+	zassert_equal(bbram_check_power(dev), 0, NULL);
+	zassert_ok(bbram_emul_set_power_state(dev, true), NULL);
+	zassert_equal(bbram_check_power(dev), 1, NULL);
+	zassert_equal(bbram_check_power(dev), 0, NULL);
+}
+
+static void test_reset_invalid_on_read(void)
+{
+	const struct device *dev = device_get_binding(BBRAM_LABEL);
+	uint8_t buffer[BBRAM_SIZE];
+
+	zassert_ok(bbram_emul_set_invalid(dev, true), NULL);
+	zassert_equal(bbram_read(dev, 0, BBRAM_SIZE, buffer), -EFAULT, NULL);
+	zassert_equal(bbram_check_invalid(dev), 0, NULL);
+}
+
+static void test_reset_invalid_on_write(void)
+{
+	const struct device *dev = device_get_binding(BBRAM_LABEL);
+	uint8_t buffer[BBRAM_SIZE];
+
+	zassert_ok(bbram_emul_set_invalid(dev, true), NULL);
+	zassert_equal(bbram_write(dev, 0, BBRAM_SIZE, buffer), -EFAULT, NULL);
+	zassert_equal(bbram_check_invalid(dev), 0, NULL);
+}
+
+static void setup(void)
+{
+	const struct device *dev = device_get_binding(BBRAM_LABEL);
+
+	bbram_emul_set_invalid(dev, false);
+	bbram_emul_set_standby_power_state(dev, false);
+	bbram_emul_set_power_state(dev, false);
+}
+
+void test_main(void)
+{
+	ztest_test_suite(
+		bbram,
+		ztest_unit_test_setup_teardown(test_get_size, setup, unit_test_noop),
+		ztest_unit_test_setup_teardown(test_bbram_out_of_bounds, setup, unit_test_noop),
+		ztest_unit_test_setup_teardown(test_read_write, setup, unit_test_noop),
+		ztest_unit_test_setup_teardown(test_set_invalid, setup, unit_test_noop),
+		ztest_unit_test_setup_teardown(test_set_standby, setup, unit_test_noop),
+		ztest_unit_test_setup_teardown(test_set_power, setup, unit_test_noop),
+		ztest_unit_test_setup_teardown(test_reset_invalid_on_read, setup, unit_test_noop),
+		ztest_unit_test_setup_teardown(test_reset_invalid_on_write, setup, unit_test_noop));
+	ztest_run_test_suite(bbram);
+}

tests/drivers/bbram/emul/testcase.yaml

@@ -0,0 +1,10 @@
+# Copyright 2021 Google LLC
+# SPDX-License-Identifier: Apache-2.0
+
+tests:
+  drivers.bbram.emul:
+    tags: drivers bbram
+    harness: ztest
+    platform_allow: native_posix
+    integration_platforms:
+      - native_posix

tests/drivers/bbram/it8xxx2.conf

@@ -0,0 +1,6 @@
+# Copyright 2021 Google LLC
+# SPDX-License-Identifier: Apache-2.0
+
+CONFIG_ZTEST=y
+CONFIG_BBRAM=y
+CONFIG_BBRAM_IT8XXX2=y

tests/drivers/bbram/npcx.conf

@@ -0,0 +1,6 @@
+# Copyright 2021 Google LLC
+# SPDX-License-Identifier: Apache-2.0
+
+CONFIG_ZTEST=y
+CONFIG_BBRAM=y
+CONFIG_BBRAM_NPCX=y

tests/drivers/bbram/src/main.c

@@ -3,123 +3,9 @@
  * SPDX-License-Identifier: Apache-2.0
  */
 
-#include <device.h>
-#include <drivers/bbram.h>
-#include <string.h>
 #include <ztest.h>
 
-#define BBRAM_NODELABEL DT_NODELABEL(bbram)
-#define BBRAM_LABEL DT_LABEL(BBRAM_NODELABEL)
-#define BBRAM_SIZE DT_PROP(BBRAM_NODELABEL, size)
-
-static void test_get_size(void)
-{
-	const struct device *dev = device_get_binding(BBRAM_LABEL);
-	size_t size;
-
-	zassert_ok(bbram_get_size(dev, &size), NULL);
-	zassert_equal(size, BBRAM_SIZE, NULL);
-}
-
-static void test_bbram_out_of_bounds(void)
-{
-	const struct device *dev = device_get_binding(BBRAM_LABEL);
-	uint8_t buffer[BBRAM_SIZE];
-
-	zassert_not_null(dev, NULL);
-	zassert_equal(bbram_read(dev, 0, 0, buffer), -EFAULT, NULL);
-	zassert_equal(bbram_read(dev, 0, BBRAM_SIZE + 1, buffer), -EFAULT, NULL);
-	zassert_equal(bbram_read(dev, BBRAM_SIZE - 1, 2, buffer), -EFAULT, NULL);
-	zassert_equal(bbram_write(dev, 0, 0, buffer), -EFAULT, NULL);
-	zassert_equal(bbram_write(dev, 0, BBRAM_SIZE + 1, buffer), -EFAULT, NULL);
-	zassert_equal(bbram_write(dev, BBRAM_SIZE - 1, 2, buffer), -EFAULT, NULL);
-}
-
-static void test_read_write(void)
-{
-	const struct device *dev = device_get_binding(BBRAM_LABEL);
-	uint8_t buffer[BBRAM_SIZE];
-	uint8_t expected[BBRAM_SIZE];
-
-	for (int i = 0; i < BBRAM_SIZE; ++i) {
-		expected[i] = i;
-	}
-	/* Set and verify content. */
-	zassert_ok(bbram_write(dev, 0, BBRAM_SIZE, expected), NULL);
-	zassert_ok(bbram_read(dev, 0, BBRAM_SIZE, buffer), NULL);
-	zassert_mem_equal(buffer, expected, BBRAM_SIZE, NULL);
-}
-
-static void test_set_invalid(void)
-{
-	const struct device *dev = device_get_binding(BBRAM_LABEL);
-
-	zassert_equal(bbram_check_invalid(dev), 0, NULL);
-	zassert_ok(bbram_emul_set_invalid(dev, true), NULL);
-	zassert_equal(bbram_check_invalid(dev), 1, NULL);
-	zassert_equal(bbram_check_invalid(dev), 0, NULL);
-}
-
-static void test_set_standby(void)
-{
-	const struct device *dev = device_get_binding(BBRAM_LABEL);
-
-	zassert_equal(bbram_check_standby_power(dev), 0, NULL);
-	zassert_ok(bbram_emul_set_standby_power_state(dev, true), NULL);
-	zassert_equal(bbram_check_standby_power(dev), 1, NULL);
-	zassert_equal(bbram_check_standby_power(dev), 0, NULL);
-}
-
-static void test_set_power(void)
-{
-	const struct device *dev = device_get_binding(BBRAM_LABEL);
-
-	zassert_equal(bbram_check_power(dev), 0, NULL);
-	zassert_ok(bbram_emul_set_power_state(dev, true), NULL);
-	zassert_equal(bbram_check_power(dev), 1, NULL);
-	zassert_equal(bbram_check_power(dev), 0, NULL);
-}
-
-static void test_reset_invalid_on_read(void)
-{
-	const struct device *dev = device_get_binding(BBRAM_LABEL);
-	uint8_t buffer[BBRAM_SIZE];
-
-	zassert_ok(bbram_emul_set_invalid(dev, true), NULL);
-	zassert_equal(bbram_read(dev, 0, BBRAM_SIZE, buffer), -EFAULT, NULL);
-	zassert_equal(bbram_check_invalid(dev), 0, NULL);
-}
-
-static void test_reset_invalid_on_write(void)
-{
-	const struct device *dev = device_get_binding(BBRAM_LABEL);
-	uint8_t buffer[BBRAM_SIZE];
-
-	zassert_ok(bbram_emul_set_invalid(dev, true), NULL);
-	zassert_equal(bbram_write(dev, 0, BBRAM_SIZE, buffer), -EFAULT, NULL);
-	zassert_equal(bbram_check_invalid(dev), 0, NULL);
-}
-
-static void setup(void)
-{
-	const struct device *dev = device_get_binding(BBRAM_LABEL);
-
-	bbram_emul_set_invalid(dev, false);
-	bbram_emul_set_standby_power_state(dev, false);
-	bbram_emul_set_power_state(dev, false);
-}
-
 void test_main(void)
 {
-	ztest_test_suite(
+	/* Build only test, this is a stub. */
-		bbram,
-		ztest_unit_test_setup_teardown(test_get_size, setup, unit_test_noop),
-		ztest_unit_test_setup_teardown(test_bbram_out_of_bounds, setup, unit_test_noop),
-		ztest_unit_test_setup_teardown(test_read_write, setup, unit_test_noop),
-		ztest_unit_test_setup_teardown(test_set_invalid, setup, unit_test_noop),
-		ztest_unit_test_setup_teardown(test_set_standby, setup, unit_test_noop),
-		ztest_unit_test_setup_teardown(test_set_power, setup, unit_test_noop),
-		ztest_unit_test_setup_teardown(test_reset_invalid_on_read, setup, unit_test_noop),
-		ztest_unit_test_setup_teardown(test_reset_invalid_on_write, setup, unit_test_noop));
-	ztest_run_test_suite(bbram);
 }

tests/drivers/bbram/testcase.yaml

@@ -1,10 +1,13 @@
 # Copyright 2021 Google LLC
 # SPDX-License-Identifier: Apache-2.0
 
+common:
+  tags: drivers bbram
+  build_only: true
+  harness: ztest
+  platform_exclude: native_posix
 tests:
-  drivers.bbram:
+  drivers.bbram.it8xxx2:
-    tags: drivers bbram
+    extra_args: CONF_FILE="it8xxx2.conf"
-    harness: ztest
+  drivers.bbram.npcx:
-    platform_allow: native_posix
+    extra_args: CONF_FILE="npcx.conf"
-    integration_platforms:
-      - native_posix