/* SPDX-License-Identifier: GPL-2.0 */ /* * Copyright (c) 2016-2018, 2020, The Linux Foundation. All rights reserved. * Copyright (c) 2024, Qualcomm Innovation Center, Inc. All rights reserved. */ #define pr_fmt(fmt) "cmd-db: " fmt #include #include #include #include #include #include #include #include #define NUM_PRIORITY 2 #define MAX_SLV_ID 8 #define SLAVE_ID_MASK 0x7 #define SLAVE_ID_SHIFT 16 #define SLAVE_ID(addr) FIELD_GET(GENMASK(19, 16), addr) #define VRM_ADDR(addr) FIELD_GET(GENMASK(19, 4), addr) /** * 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 const void *rsc_to_entry_header(const struct rsc_hdr *hdr) { u16 offset = le16_to_cpu(hdr->header_offset); return cmd_db_header->data + offset; } static inline void * rsc_offset(const struct rsc_hdr *hdr, const 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_GPL(cmd_db_ready); static int cmd_db_get_header(const char *id, const struct entry_header **eh, const struct rsc_hdr **rh) { const struct rsc_hdr *rsc_hdr; const struct entry_header *ent; int ret, i, j; u8 query[sizeof(ent->id)] __nonstring; ret = cmd_db_ready(); if (ret) return ret; strtomem_pad(query, id, 0); 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) { if (eh) *eh = ent; if (rh) *rh = rsc_hdr; 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; const struct entry_header *ent; ret = cmd_db_get_header(id, &ent, NULL); return ret < 0 ? 0 : le32_to_cpu(ent->addr); } EXPORT_SYMBOL_GPL(cmd_db_read_addr); 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; } device_set_pm_not_required(&pdev->dev); return 0; } static const struct of_device_id cmd_db_match_table[] = { { .compatible = "qcom,cmd-db" }, { } }; MODULE_DEVICE_TABLE(of, cmd_db_match_table); static struct platform_driver cmd_db_dev_driver = { .probe = cmd_db_dev_probe, .driver = { .name = "cmd-db", .of_match_table = cmd_db_match_table, .suppress_bind_attrs = true, }, }; static int __init cmd_db_device_init(void) { return platform_driver_register(&cmd_db_dev_driver); } core_initcall(cmd_db_device_init); MODULE_DESCRIPTION("Qualcomm Technologies, Inc. Command DB Driver"); MODULE_LICENSE("GPL v2");