diff options
Diffstat (limited to 'drivers/soc/qcom/cmd-db.c')
-rw-r--r-- | drivers/soc/qcom/cmd-db.c | 317 |
1 files changed, 317 insertions, 0 deletions
diff --git a/drivers/soc/qcom/cmd-db.c b/drivers/soc/qcom/cmd-db.c new file mode 100644 index 000000000..78d73ec58 --- /dev/null +++ b/drivers/soc/qcom/cmd-db.c @@ -0,0 +1,317 @@ +/* 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 (!cmd_db_header) { + ret = -ENOMEM; + 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); |