drivers/soc/qcom/cmd-db.c - third_party/linux - Git at Google

 /* SPDX-License-Identifier: GPL-2.0 */
 /* Copyright (c) 2016-2018, The Linux Foundation. All rights reserved. */

 #include <linux/kernel.h>
 #include <linux/of.h>
 #include <linux/of_address.h>
 #include <linux/of_platform.h>
 #include <linux/of_reserved_mem.h>
 #include <linux/platform_device.h>
 #include <linux/types.h>

 #include <soc/qcom/cmd-db.h>

 #define NUM_PRIORITY		2
 #define MAX_SLV_ID		8
 #define SLAVE_ID_MASK		0x7
 #define SLAVE_ID_SHIFT		16

 /**
  * struct entry_header: header for each entry in cmddb
  *
  * @id: resource's identifier
  * @priority: unused
  * @addr: the address of the resource
  * @len: length of the data
  * @offset: offset from :@data_offset, start of the data
  */
 struct entry_header {
 	u8 id[8];
 	__le32 priority[NUM_PRIORITY];
 	__le32 addr;
 	__le16 len;
 	__le16 offset;
 };

 /**
  * struct rsc_hdr: resource header information
  *
  * @slv_id: id for the resource
  * @header_offset: entry's header at offset from the end of the cmd_db_header
  * @data_offset: entry's data at offset from the end of the cmd_db_header
  * @cnt: number of entries for HW type
  * @version: MSB is major, LSB is minor
  * @reserved: reserved for future use.
  */
 struct rsc_hdr {
 	__le16 slv_id;
 	__le16 header_offset;
 	__le16 data_offset;
 	__le16 cnt;
 	__le16 version;
 	__le16 reserved[3];
 };

 /**
  * struct cmd_db_header: The DB header information
  *
  * @version: The cmd db version
  * @magic: constant expected in the database
  * @header: array of resources
  * @checksum: checksum for the header. Unused.
  * @reserved: reserved memory
  * @data: driver specific data
  */
 struct cmd_db_header {
 	__le32 version;
 	u8 magic[4];
 	struct rsc_hdr header[MAX_SLV_ID];
 	__le32 checksum;
 	__le32 reserved;
 	u8 data[];
 };

 /**
  * DOC: Description of the Command DB database.
  *
  * At the start of the command DB memory is the cmd_db_header structure.
  * The cmd_db_header holds the version, checksum, magic key as well as an
  * array for header for each slave (depicted by the rsc_header). Each h/w
  * based accelerator is a 'slave' (shared resource) and has slave id indicating
  * the type of accelerator. The rsc_header is the header for such individual
  * slaves of a given type. The entries for each of these slaves begin at the
  * rsc_hdr.header_offset. In addition each slave could have auxiliary data
  * that may be needed by the driver. The data for the slave starts at the
  * entry_header.offset to the location pointed to by the rsc_hdr.data_offset.
  *
  * Drivers have a stringified key to a slave/resource. They can query the slave
  * information and get the slave id and the auxiliary data and the length of the
  * data. Using this information, they can format the request to be sent to the
  * h/w accelerator and request a resource state.
  */

 static const u8 CMD_DB_MAGIC[] = { 0xdb, 0x30, 0x03, 0x0c };

 static bool cmd_db_magic_matches(const struct cmd_db_header *header)
 {
 	const u8 *magic = header->magic;

 	return memcmp(magic, CMD_DB_MAGIC, ARRAY_SIZE(CMD_DB_MAGIC)) == 0;
 }

 static struct cmd_db_header *cmd_db_header;


 static inline void *rsc_to_entry_header(struct rsc_hdr *hdr)
 {
 	u16 offset = le16_to_cpu(hdr->header_offset);

 	return cmd_db_header->data + offset;
 }

 static inline void *
 rsc_offset(struct rsc_hdr *hdr, struct entry_header *ent)
 {
 	u16 offset = le16_to_cpu(hdr->data_offset);
 	u16 loffset = le16_to_cpu(ent->offset);

 	return cmd_db_header->data + offset + loffset;
 }

 /**
  * cmd_db_ready - Indicates if command DB is available
  *
  * Return: 0 on success, errno otherwise
  */
 int cmd_db_ready(void)
 {
 	if (cmd_db_header == NULL)
 		return -EPROBE_DEFER;
 	else if (!cmd_db_magic_matches(cmd_db_header))
 		return -EINVAL;

 	return 0;
 }
 EXPORT_SYMBOL(cmd_db_ready);

 static int cmd_db_get_header(const char *id, struct entry_header *eh,
 			     struct rsc_hdr *rh)
 {
 	struct rsc_hdr *rsc_hdr;
 	struct entry_header *ent;
 	int ret, i, j;
 	u8 query[8];

 	ret = cmd_db_ready();
 	if (ret)
 		return ret;

 	if (!eh || !rh)
 		return -EINVAL;

 	/* Pad out query string to same length as in DB */
 	strncpy(query, id, sizeof(query));

 	for (i = 0; i < MAX_SLV_ID; i++) {
 		rsc_hdr = &cmd_db_header->header[i];
 		if (!rsc_hdr->slv_id)
 			break;

 		ent = rsc_to_entry_header(rsc_hdr);
 		for (j = 0; j < le16_to_cpu(rsc_hdr->cnt); j++, ent++) {
 			if (memcmp(ent->id, query, sizeof(ent->id)) == 0)
 				break;
 		}

 		if (j < le16_to_cpu(rsc_hdr->cnt)) {
 			memcpy(eh, ent, sizeof(*ent));
 			memcpy(rh, rsc_hdr, sizeof(*rh));
 			return 0;
 		}
 	}

 	return -ENODEV;
 }

 /**
  * cmd_db_read_addr() - Query command db for resource id address.
  *
  * @id: resource id to query for address
  *
  * Return: resource address on success, 0 on error
  *
  * This is used to retrieve resource address based on resource
  * id.
  */
 u32 cmd_db_read_addr(const char *id)
 {
 	int ret;
 	struct entry_header ent;
 	struct rsc_hdr rsc_hdr;

 	ret = cmd_db_get_header(id, &ent, &rsc_hdr);

 	return ret < 0 ? 0 : le32_to_cpu(ent.addr);
 }
 EXPORT_SYMBOL(cmd_db_read_addr);

 /**
  * cmd_db_read_aux_data() - Query command db for aux data.
  *
  *  @id: Resource to retrieve AUX Data on.
  *  @data: Data buffer to copy returned aux data to. Returns size on NULL
  *  @len: Caller provides size of data buffer passed in.
  *
  *  Return: size of data on success, errno otherwise
  */
 int cmd_db_read_aux_data(const char *id, u8 *data, size_t len)
 {
 	int ret;
 	struct entry_header ent;
 	struct rsc_hdr rsc_hdr;
 	u16 ent_len;

 	if (!data)
 		return -EINVAL;

 	ret = cmd_db_get_header(id, &ent, &rsc_hdr);
 	if (ret)
 		return ret;

 	ent_len = le16_to_cpu(ent.len);
 	if (len < ent_len)
 		return -EINVAL;

 	len = min_t(u16, ent_len, len);
 	memcpy(data, rsc_offset(&rsc_hdr, &ent), len);

 	return len;
 }
 EXPORT_SYMBOL(cmd_db_read_aux_data);

 /**
  * cmd_db_read_aux_data_len - Get the length of the auxiliary data stored in DB.
  *
  * @id: Resource to retrieve AUX Data.
  *
  * Return: size on success, 0 on error
  */
 size_t cmd_db_read_aux_data_len(const char *id)
 {
 	int ret;
 	struct entry_header ent;
 	struct rsc_hdr rsc_hdr;

 	ret = cmd_db_get_header(id, &ent, &rsc_hdr);

 	return ret < 0 ? 0 : le16_to_cpu(ent.len);
 }
 EXPORT_SYMBOL(cmd_db_read_aux_data_len);

 /**
  * cmd_db_read_slave_id - Get the slave ID for a given resource address
  *
  * @id: Resource id to query the DB for version
  *
  * Return: cmd_db_hw_type enum on success, CMD_DB_HW_INVALID on error
  */
 enum cmd_db_hw_type cmd_db_read_slave_id(const char *id)
 {
 	int ret;
 	struct entry_header ent;
 	struct rsc_hdr rsc_hdr;
 	u32 addr;

 	ret = cmd_db_get_header(id, &ent, &rsc_hdr);
 	if (ret < 0)
 		return CMD_DB_HW_INVALID;

 	addr = le32_to_cpu(ent.addr);
 	return (addr >> SLAVE_ID_SHIFT) & SLAVE_ID_MASK;
 }
 EXPORT_SYMBOL(cmd_db_read_slave_id);

 static int cmd_db_dev_probe(struct platform_device *pdev)
 {
 	struct reserved_mem *rmem;
 	int ret = 0;

 	rmem = of_reserved_mem_lookup(pdev->dev.of_node);
 	if (!rmem) {
 		dev_err(&pdev->dev, "failed to acquire memory region\n");
 		return -EINVAL;
 	}

 	cmd_db_header = memremap(rmem->base, rmem->size, MEMREMAP_WB);
 	if (IS_ERR_OR_NULL(cmd_db_header)) {
 		ret = PTR_ERR(cmd_db_header);
 		cmd_db_header = NULL;
 		return ret;
 	}

 	if (!cmd_db_magic_matches(cmd_db_header)) {
 		dev_err(&pdev->dev, "Invalid Command DB Magic\n");
 		return -EINVAL;
 	}

 	return 0;
 }

 static const struct of_device_id cmd_db_match_table[] = {
 	{ .compatible = "qcom,cmd-db" },
 	{ },
 };

 static struct platform_driver cmd_db_dev_driver = {
 	.probe  = cmd_db_dev_probe,
 	.driver = {
 		   .name = "cmd-db",
 		   .of_match_table = cmd_db_match_table,
 	},
 };

 static int __init cmd_db_device_init(void)
 {
 	return platform_driver_register(&cmd_db_dev_driver);
 }
 arch_initcall(cmd_db_device_init);
	/* SPDX-License-Identifier: GPL-2.0 */
	/* Copyright (c) 2016-2018, The Linux Foundation. All rights reserved. */

	#include <linux/kernel.h>
	#include <linux/of.h>
	#include <linux/of_address.h>
	#include <linux/of_platform.h>
	#include <linux/of_reserved_mem.h>
	#include <linux/platform_device.h>
	#include <linux/types.h>

	#include <soc/qcom/cmd-db.h>

	#define NUM_PRIORITY 2
	#define MAX_SLV_ID 8
	#define SLAVE_ID_MASK 0x7
	#define SLAVE_ID_SHIFT 16

	/**
	* struct entry_header: header for each entry in cmddb
	*
	* @id: resource's identifier
	* @priority: unused
	* @addr: the address of the resource
	* @len: length of the data
	* @offset: offset from :@data_offset, start of the data
	*/
	struct entry_header {
	u8 id[8];
	__le32 priority[NUM_PRIORITY];
	__le32 addr;
	__le16 len;
	__le16 offset;
	};

	/**
	* struct rsc_hdr: resource header information
	*
	* @slv_id: id for the resource
	* @header_offset: entry's header at offset from the end of the cmd_db_header
	* @data_offset: entry's data at offset from the end of the cmd_db_header
	* @cnt: number of entries for HW type
	* @version: MSB is major, LSB is minor
	* @reserved: reserved for future use.
	*/
	struct rsc_hdr {
	__le16 slv_id;
	__le16 header_offset;
	__le16 data_offset;
	__le16 cnt;
	__le16 version;
	__le16 reserved[3];
	};

	/**
	* struct cmd_db_header: The DB header information
	*
	* @version: The cmd db version
	* @magic: constant expected in the database
	* @header: array of resources
	* @checksum: checksum for the header. Unused.
	* @reserved: reserved memory
	* @data: driver specific data
	*/
	struct cmd_db_header {
	__le32 version;
	u8 magic[4];
	struct rsc_hdr header[MAX_SLV_ID];
	__le32 checksum;
	__le32 reserved;
	u8 data[];
	};

	/**
	* DOC: Description of the Command DB database.
	*
	* At the start of the command DB memory is the cmd_db_header structure.
	* The cmd_db_header holds the version, checksum, magic key as well as an
	* array for header for each slave (depicted by the rsc_header). Each h/w
	* based accelerator is a 'slave' (shared resource) and has slave id indicating
	* the type of accelerator. The rsc_header is the header for such individual
	* slaves of a given type. The entries for each of these slaves begin at the
	* rsc_hdr.header_offset. In addition each slave could have auxiliary data
	* that may be needed by the driver. The data for the slave starts at the
	* entry_header.offset to the location pointed to by the rsc_hdr.data_offset.
	*
	* Drivers have a stringified key to a slave/resource. They can query the slave
	* information and get the slave id and the auxiliary data and the length of the
	* data. Using this information, they can format the request to be sent to the
	* h/w accelerator and request a resource state.
	*/

	static const u8 CMD_DB_MAGIC[] = { 0xdb, 0x30, 0x03, 0x0c };

	static bool cmd_db_magic_matches(const struct cmd_db_header *header)
	{
	const u8 *magic = header->magic;

	return memcmp(magic, CMD_DB_MAGIC, ARRAY_SIZE(CMD_DB_MAGIC)) == 0;
	}

	static struct cmd_db_header *cmd_db_header;


	static inline void rsc_to_entry_header(struct rsc_hdr hdr)
	{
	u16 offset = le16_to_cpu(hdr->header_offset);

	return cmd_db_header->data + offset;
	}

	static inline void *
	rsc_offset(struct rsc_hdr hdr, struct entry_header ent)
	{
	u16 offset = le16_to_cpu(hdr->data_offset);
	u16 loffset = le16_to_cpu(ent->offset);

	return cmd_db_header->data + offset + loffset;
	}

	/**
	* cmd_db_ready - Indicates if command DB is available
	*
	* Return: 0 on success, errno otherwise
	*/
	int cmd_db_ready(void)
	{
	if (cmd_db_header == NULL)
	return -EPROBE_DEFER;
	else if (!cmd_db_magic_matches(cmd_db_header))
	return -EINVAL;

	return 0;
	}
	EXPORT_SYMBOL(cmd_db_ready);

	static int cmd_db_get_header(const char id, struct entry_header eh,
	struct rsc_hdr *rh)
	{
	struct rsc_hdr *rsc_hdr;
	struct entry_header *ent;
	int ret, i, j;
	u8 query[8];

	ret = cmd_db_ready();
	if (ret)
	return ret;

	if (!eh \|\| !rh)
	return -EINVAL;

	/* Pad out query string to same length as in DB */
	strncpy(query, id, sizeof(query));

	for (i = 0; i < MAX_SLV_ID; i++) {
	rsc_hdr = &cmd_db_header->header[i];
	if (!rsc_hdr->slv_id)
	break;

	ent = rsc_to_entry_header(rsc_hdr);
	for (j = 0; j < le16_to_cpu(rsc_hdr->cnt); j++, ent++) {
	if (memcmp(ent->id, query, sizeof(ent->id)) == 0)
	break;
	}

	if (j < le16_to_cpu(rsc_hdr->cnt)) {
	memcpy(eh, ent, sizeof(*ent));
	memcpy(rh, rsc_hdr, sizeof(*rh));
	return 0;
	}
	}

	return -ENODEV;
	}

	/**
	* cmd_db_read_addr() - Query command db for resource id address.
	*
	* @id: resource id to query for address
	*
	* Return: resource address on success, 0 on error
	*
	* This is used to retrieve resource address based on resource
	* id.
	*/
	u32 cmd_db_read_addr(const char *id)
	{
	int ret;
	struct entry_header ent;
	struct rsc_hdr rsc_hdr;

	ret = cmd_db_get_header(id, &ent, &rsc_hdr);

	return ret < 0 ? 0 : le32_to_cpu(ent.addr);
	}
	EXPORT_SYMBOL(cmd_db_read_addr);

	/**
	* cmd_db_read_aux_data() - Query command db for aux data.
	*
	* @id: Resource to retrieve AUX Data on.
	* @data: Data buffer to copy returned aux data to. Returns size on NULL
	* @len: Caller provides size of data buffer passed in.
	*
	* Return: size of data on success, errno otherwise
	*/
	int cmd_db_read_aux_data(const char id, u8 data, size_t len)
	{
	int ret;
	struct entry_header ent;
	struct rsc_hdr rsc_hdr;
	u16 ent_len;

	if (!data)
	return -EINVAL;

	ret = cmd_db_get_header(id, &ent, &rsc_hdr);
	if (ret)
	return ret;

	ent_len = le16_to_cpu(ent.len);
	if (len < ent_len)
	return -EINVAL;

	len = min_t(u16, ent_len, len);
	memcpy(data, rsc_offset(&rsc_hdr, &ent), len);

	return len;
	}
	EXPORT_SYMBOL(cmd_db_read_aux_data);

	/**
	* cmd_db_read_aux_data_len - Get the length of the auxiliary data stored in DB.
	*
	* @id: Resource to retrieve AUX Data.
	*
	* Return: size on success, 0 on error
	*/
	size_t cmd_db_read_aux_data_len(const char *id)
	{
	int ret;
	struct entry_header ent;
	struct rsc_hdr rsc_hdr;

	ret = cmd_db_get_header(id, &ent, &rsc_hdr);

	return ret < 0 ? 0 : le16_to_cpu(ent.len);
	}
	EXPORT_SYMBOL(cmd_db_read_aux_data_len);

	/**
	* cmd_db_read_slave_id - Get the slave ID for a given resource address
	*
	* @id: Resource id to query the DB for version
	*
	* Return: cmd_db_hw_type enum on success, CMD_DB_HW_INVALID on error
	*/
	enum cmd_db_hw_type cmd_db_read_slave_id(const char *id)
	{
	int ret;
	struct entry_header ent;
	struct rsc_hdr rsc_hdr;
	u32 addr;

	ret = cmd_db_get_header(id, &ent, &rsc_hdr);
	if (ret < 0)
	return CMD_DB_HW_INVALID;

	addr = le32_to_cpu(ent.addr);
	return (addr >> SLAVE_ID_SHIFT) & SLAVE_ID_MASK;
	}
	EXPORT_SYMBOL(cmd_db_read_slave_id);

	static int cmd_db_dev_probe(struct platform_device *pdev)
	{
	struct reserved_mem *rmem;
	int ret = 0;

	rmem = of_reserved_mem_lookup(pdev->dev.of_node);
	if (!rmem) {
	dev_err(&pdev->dev, "failed to acquire memory region\n");
	return -EINVAL;
	}

	cmd_db_header = memremap(rmem->base, rmem->size, MEMREMAP_WB);
	if (IS_ERR_OR_NULL(cmd_db_header)) {
	ret = PTR_ERR(cmd_db_header);
	cmd_db_header = NULL;
	return ret;
	}

	if (!cmd_db_magic_matches(cmd_db_header)) {
	dev_err(&pdev->dev, "Invalid Command DB Magic\n");
	return -EINVAL;
	}

	return 0;
	}

	static const struct of_device_id cmd_db_match_table[] = {
	{ .compatible = "qcom,cmd-db" },
	{ },
	};

	static struct platform_driver cmd_db_dev_driver = {
	.probe = cmd_db_dev_probe,
	.driver = {
	.name = "cmd-db",
	.of_match_table = cmd_db_match_table,
	},
	};

	static int __init cmd_db_device_init(void)
	{
	return platform_driver_register(&cmd_db_dev_driver);
	}
	arch_initcall(cmd_db_device_init);