tegra/platform: Add driver for firmware class and inventory

Add driver for common utility API for firmware class and
dumping the inventory for all firmware.

Bug 3583607

Change-Id: I259bc7f80b8842cea090f67b067f63e5f85cb79c
Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Reviewed-on: https://git-master.nvidia.com/r/c/linux-nv-oot/+/2708890
GVS: Gerrit_Virtual_Submit

drivers/platform/tegra/Makefile

@@ -3,6 +3,9 @@
 
 obj-m += bad.o
 
+obj-m += firmwares-class.o
+obj-m += firmwares-inventory.o
+
 tegra-bootloader-debug-objs := tegra_bootloader_debug.o
 tegra-bootloader-debug-objs += tegra_bootloader_debug_init.o
 obj-m += tegra-bootloader-debug.o

drivers/platform/tegra/firmwares-class.c

@@ -0,0 +1,309 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (c) 2022, NVIDIA CORPORATION, All rights reserved.
+
+#include <linux/module.h>
+#include <linux/version.h>
+#include <linux/device.h>
+#include <linux/slab.h>
+#include <linux/of.h>
+#include <linux/tegra-firmwares.h>
+
+struct tegrafw_data {
+	u32	flags;
+	ssize_t	(*reader)(struct device *dev, char *data, size_t size);
+	char	*saved_string;
+	struct mutex lock;
+};
+
+void tegrafw_invalidate(struct device *fwdev)
+{
+	struct tegrafw_data *tfw = fwdev->platform_data;
+
+	if (!tfw->reader) {
+		dev_warn(fwdev, "attempt to invalidate when reader is NULL\n");
+		return;
+	}
+	mutex_lock(&tfw->lock);
+	if (tfw->saved_string)
+		devm_kfree(fwdev, tfw->saved_string);
+	tfw->saved_string = NULL;
+	mutex_unlock(&tfw->lock);
+}
+
+static ssize_t version_show(struct device *fwdev,
+			struct device_attribute *attr, char *buf)
+{
+	struct tegrafw_data *tfw = fwdev->platform_data;
+	char *version_string;
+	char reader_string[TFW_VERSION_MAX_SIZE];
+	ssize_t r;
+
+	mutex_lock(&tfw->lock);
+	if (tfw->saved_string) {
+		version_string = tfw->saved_string;
+	} else {
+		tfw->reader(fwdev->parent,
+			reader_string, sizeof(reader_string));
+		version_string = reader_string;
+		if ((tfw->flags & TFW_DONT_CACHE) == 0) {
+			if (tfw->saved_string)
+				devm_kfree(fwdev, tfw->saved_string);
+			tfw->saved_string = devm_kstrdup(fwdev,
+				version_string, GFP_KERNEL);
+		}
+	}
+	r = snprintf(buf, PAGE_SIZE, "%s: %s\n",
+		dev_name(fwdev), version_string);
+	mutex_unlock(&tfw->lock);
+	return r;
+}
+
+static int versions_show_one(struct device *fwdev, void *buf)
+{
+	if (version_show(fwdev, NULL, buf + strlen(buf)) > 0)
+		return 0;
+	else
+		return -ENOMEM;
+}
+
+static ssize_t versions_show(struct class *cls,
+	struct class_attribute *attr, char *buf)
+{
+	buf[0] = '\0';
+	class_for_each_device(cls, NULL, buf, versions_show_one);
+	return strlen(buf);
+}
+
+static DEVICE_ATTR_RO(version);
+
+static struct attribute *tegrafw_attrs[] = {
+	&dev_attr_version.attr,
+	NULL,
+};
+
+ATTRIBUTE_GROUPS(tegrafw);
+
+#if LINUX_VERSION_CODE < KERNEL_VERSION(4, 14, 0)
+/*
+ * old kernels, deprecated
+ */
+static struct class_attribute tegrafw_class_attrs[] = {
+	__ATTR(versions, S_IRUGO, versions_show, NULL),
+	__ATTR_NULL,
+};
+#else
+static CLASS_ATTR_RO(versions);
+
+static struct attribute *tegrafw_class_attrs[] = {
+	&class_attr_versions.attr,
+	NULL,
+};
+
+ATTRIBUTE_GROUPS(tegrafw_class);
+#endif
+
+static void tegrafw_release(struct device *dev)
+{
+	kfree(dev);
+}
+
+static bool tegrafw_class_registered;
+
+static struct class tegrafw_class = {
+	.name = "tegra-firmware",
+	.owner = THIS_MODULE,
+#if LINUX_VERSION_CODE < KERNEL_VERSION(4, 14, 0)
+	/* old kernels... */
+	.class_attrs = tegrafw_class_attrs,
+#else
+	.class_groups = tegrafw_class_groups,
+#endif
+};
+
+
+/**
+ * tegrafw_register - register the firmware object
+ *
+ * @name: the firmware symbolic name, will be created under tegra-firmwares
+ * @flags: only %TFW_DONT_CACHE is supported for now - always call @reader
+ * @reader: function to print version info
+ * @string: predefined string to return as a version
+ *
+ * Return value: error code if IS_ERR(), otherwise valid firmware object.
+ *               Needs to be deallocated with call to tegrafw_unregister()
+ */
+struct device *tegrafw_register(const char *name,
+			const u32 flags,
+			ssize_t (*reader)(struct device *, char *, size_t),
+			const char *string)
+{
+	struct device *fwdev = NULL;
+	int err;
+	struct tegrafw_data *tfw;
+
+	if (!name) {
+		pr_err("%s: attempt to register unnamed firmware",
+			__func__);
+		err = -EINVAL;
+		goto out;
+	}
+	if ((flags & TFW_DONT_CACHE) && !reader) {
+		pr_err("%s: don't cache and no reader?\n",
+			name);
+		err = -EINVAL;
+		goto out;
+	}
+	if (reader && string)
+		pr_info("%s: string will be used instead of calls to reader",
+			name);
+
+	fwdev = kzalloc(sizeof(*fwdev) + sizeof(*tfw), GFP_KERNEL);
+	if (!fwdev) {
+		err = -ENOMEM;
+		goto out;
+	}
+
+	if (!tegrafw_class_registered) {
+		class_register(&tegrafw_class);
+		tegrafw_class_registered = true;
+	}
+
+	device_initialize(fwdev);
+	dev_set_name(fwdev, "%s", name);
+	tfw = (struct tegrafw_data *)(fwdev + 1);
+	mutex_init(&tfw->lock);
+	tfw->flags = flags;
+	tfw->reader = reader;
+	tfw->saved_string = string ?
+		devm_kstrdup(fwdev, string, GFP_KERNEL) : NULL;
+	fwdev->platform_data = tfw;
+	fwdev->release = tegrafw_release;
+	fwdev->class = &tegrafw_class;
+	fwdev->groups = tegrafw_groups;
+
+	err = device_add(fwdev);
+	if (err < 0)
+		goto out;
+
+	return fwdev;
+out:
+	put_device(fwdev);
+	return ERR_PTR(err);
+}
+EXPORT_SYMBOL(tegrafw_register);
+
+/**
+ * tegrafw_unregister - release the firmware object
+ *
+ * @dev: device object returned by previous call to tegrafw_register()
+ */
+void tegrafw_unregister(struct device *fwdev)
+{
+	if (!IS_ERR_OR_NULL(fwdev))
+		device_unregister(fwdev);
+}
+EXPORT_SYMBOL(tegrafw_unregister);
+
+/*
+ * devm_tegrafw_match - used by the devres framework to search devres
+ *                      that matches the data
+ * For tegrafw devres, resource holds the pointer to the data, so
+ * simple *res = data will work.
+ * Neither res nor *res should be NULL, in this case we return 0 to indicate
+ * mismatch
+ */
+static int devm_tegrafw_match(struct device *dev, void *res, void *data)
+{
+	struct device **p = res;
+
+	if (WARN_ON(!p || !*p))
+		return 0;
+	return *p == data;
+}
+
+static void devm_tegrafw_release(struct device *dev, void *res)
+{
+	tegrafw_unregister(*(struct device **)res);
+}
+
+/**
+ * devm_tegrafw_regsiter - register "managed" firmware
+ *
+ * @dev: owner of the firmware
+ * @name: symbolic name. If %NULL, device name will be used
+ * @flags: only %TFW_DONT_CACHE is supported right now - always call @reader
+ * @reader: function to print version info
+ * @string: predefined string to return as a version
+ *
+ * Return: struct device or appropriate error code wrapped in ERR_PTR()
+ */
+struct device *devm_tegrafw_register(struct device *dev, const char *name,
+			const u32 flags,
+			ssize_t (*reader)(struct device *, char *, size_t),
+			const char *string)
+{
+	struct device **ptr, *fwdev;
+
+	if (dev == NULL)
+		return tegrafw_register(name, flags, reader, string);
+
+	ptr = devres_alloc(devm_tegrafw_release, sizeof(*ptr), GFP_KERNEL);
+	if (!ptr)
+		return ERR_PTR(-ENOMEM);
+
+	fwdev = tegrafw_register(name ?: dev_name(dev), flags, reader, string);
+	if (!IS_ERR(fwdev)) {
+		*ptr = fwdev;
+		devres_add(dev, ptr);
+		/* set device parent */
+		device_move(fwdev, dev, DPM_ORDER_NONE);
+	} else {
+		devres_free(ptr);
+	}
+	return fwdev;
+}
+EXPORT_SYMBOL(devm_tegrafw_register);
+
+/**
+ * devm_tegrafw_unregister - unregister "managed" firmware
+ * @dev: owner of the firmware
+ * @fwdev: object returned by devm_tegrafw_register()
+ *
+ * One usually does not need it, as unregistering will take place automatically
+ */
+void devm_tegrafw_unregister(struct device *dev, struct device *fwdev)
+{
+	WARN_ON(devres_release(dev, devm_tegrafw_release,
+				devm_tegrafw_match, fwdev));
+}
+EXPORT_SYMBOL(devm_tegrafw_unregister);
+
+struct device *devm_tegrafw_register_dt_string(struct device *dev,
+						const char *name,
+						const char *path,
+						const char *property)
+{
+	struct device_node *dn;
+	const char *data;
+
+	dn = of_find_node_by_path(path);
+	if (!dn)
+		return ERR_PTR(-ENODEV);
+	if (of_property_read_string(dn, property, &data))
+		return ERR_PTR(-ENOENT);
+	of_node_put(dn);
+	return devm_tegrafw_register(dev, name, TFW_NORMAL, NULL, data);
+}
+EXPORT_SYMBOL(devm_tegrafw_register_dt_string);
+
+static void tegrafw_exit(void)
+{
+	if (tegrafw_class_registered)
+		class_unregister(&tegrafw_class);
+}
+
+module_exit(tegrafw_exit);
+MODULE_AUTHOR("dmitry pervushin <dpervushin@nvidia.com>");
+MODULE_DESCRIPTION("Tegra firmwares inventory");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:tegra-firmwares");

drivers/platform/tegra/firmwares-inventory.c

@@ -0,0 +1,112 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (c) 2022, NVIDIA CORPORATION, All rights reserved.
+
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/slab.h>
+#include <linux/of_platform.h>
+#include <linux/tegra-firmwares.h>
+#include <linux/cpu.h>
+#include <asm/cpu.h>
+
+#if IS_ENABLED(CONFIG_TRUSTY)
+#include <linux/trusty/trusty.h>
+
+static ssize_t tegrafw_read_trusty(struct device *dev,
+				char *data, size_t size)
+{
+	const struct of_device_id trusty_of_match[] = {
+		{.compatible = "android,trusty-smc-v1", },
+		{},
+	};
+	struct device_node *dn;
+	struct platform_device *pdev;
+
+	for_each_matching_node(dn, trusty_of_match) {
+		pdev = of_find_device_by_node(dn);
+		if (pdev == NULL)
+			continue;
+		return snprintf(data, size, "%s",
+			trusty_version_str_get(&pdev->dev));
+	}
+	snprintf(data, size, "NULL");
+	return 0;
+}
+#endif
+
+/* TBD: cpu_data is define in arch/arm64/kernel/cpuinfo.c
+ * It is not exported and hence defining locally for the
+ * build success.
+ * Denver FW need to be deprecated.
+ */
+DEFINE_PER_CPU(struct cpuinfo_arm64, cpu_data);
+static ssize_t tegrafw_read_denver(struct device *dev,
+				char *version, size_t size)
+{
+	char *v = version;
+	int i;
+	size_t printed = 0;
+
+	for_each_online_cpu(i) {
+		struct cpuinfo_arm64 *cpuinfo = &per_cpu(cpu_data, i);
+		u32 midr = cpuinfo->reg_midr;
+		u32 aidr;
+
+		if (MIDR_IMPLEMENTOR(midr) == ARM_CPU_IMP_NVIDIA) {
+			asm volatile("mrs %0, AIDR_EL1" : "=r" (aidr) : );
+			printed = snprintf(v, size, "CPU%d: %u(0x%x) ",
+				i, aidr, aidr);
+			size -= printed;
+			v += printed;
+		}
+	}
+
+	return v - version;
+}
+
+#define FIRMWARES_SIZE  10
+static struct device *firmwares[FIRMWARES_SIZE];
+#define check_out_of_bounds(dev, err) \
+	if ((dev) - firmwares >= ARRAY_SIZE(firmwares)) { \
+		pr_err("Cannot register 'legacy' firmware info: increase " \
+			"firmwares array size"); \
+		return (err); \
+	}
+
+static int __init tegra_firmwares_init(void)
+{
+	struct device **dev = firmwares;
+	char *versions[] = { "mb1", "mb2", "mb1-bct", "qb", "osl" };
+	int v;
+
+	check_out_of_bounds(dev, 0);
+	*dev++ = tegrafw_register("MTS", TFW_NORMAL, tegrafw_read_denver, NULL);
+
+#if IS_ENABLED(CONFIG_TRUSTY)
+	check_out_of_bounds(dev, 0);
+	*dev++ = tegrafw_register("trusty", TFW_DONT_CACHE,
+				tegrafw_read_trusty, NULL);
+#endif
+
+	for (v = 0; v < ARRAY_SIZE(versions); v++) {
+		check_out_of_bounds(dev, 0);
+		*dev++ = tegrafw_register_dt_string(versions[v],
+			"/tegra-firmwares", versions[v]);
+	}
+	return 0;
+}
+
+static void __exit tegra_firmwares_exit(void)
+{
+	struct device **dev = firmwares;
+
+	while (dev - firmwares < ARRAY_SIZE(firmwares))
+		tegrafw_unregister(*dev++);
+}
+module_init(tegra_firmwares_init);
+module_exit(tegra_firmwares_exit);
+
+MODULE_DESCRIPTION("Firmware info drivers");
+MODULE_AUTHOR("dmitry pervushin <dpervushin@nvidia.com>");
+MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>");
+MODULE_LICENSE("GPL v2");

include/linux/tegra-firmwares.h

@@ -0,0 +1,54 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (c) 2022, NVIDIA CORPORATION, All rights reserved.
+
+#ifndef __TEGRA_FIRMWARES_H
+#define __TEGRA_FIRMWARES_H
+
+/*
+ * max size of version string
+ */
+#define TFW_VERSION_MAX_SIZE 256
+
+struct device *tegrafw_register(const char *name,
+			const u32 flags,
+			ssize_t (*reader)(struct device *dev, char *, size_t),
+			const char *string);
+void tegrafw_unregister(struct device *fwdev);
+struct device *devm_tegrafw_register(struct device *dev,
+			const char *name,
+			const u32 flags,
+			ssize_t (*reader)(struct device *dev, char *, size_t),
+			const char *string);
+void devm_tegrafw_unregister(struct device *dev, struct device *fwdev);
+void tegrafw_invalidate(struct device *fwdev);
+struct device *devm_tegrafw_register_dt_string(struct device *dev,
+						const char *name,
+						const char *path,
+						const char *property);
+enum {
+	TFW_NORMAL	= 0x0000,
+	TFW_DONT_CACHE	= 0x0001,
+	TFW_MAX		= 0xFFFF,
+};
+
+static inline struct device *tegrafw_register_string(const char *name,
+						     const char *string)
+{
+	return tegrafw_register(name, TFW_NORMAL, NULL, string);
+}
+
+static inline struct device *devm_tegrafw_register_string(struct device *dev,
+						     const char *name,
+						     const char *string)
+{
+	return devm_tegrafw_register(dev, name, TFW_NORMAL, NULL, string);
+}
+
+static inline struct device *tegrafw_register_dt_string(const char *name,
+							const char *path,
+							const char *property)
+{
+	return devm_tegrafw_register_dt_string(NULL, name, path, property);
+}
+
+#endif /* __TEGRA_FIRMWARES_CLASS */