1/* SPDX-License-Identifier: GPL-2.0 */
  2/*
  3 * Copyright (c) 2016-2018, 2020, The Linux Foundation. All rights reserved.
  4 * Copyright (c) 2024, Qualcomm Innovation Center, Inc. All rights reserved.
  5 */
  6
  7#include <linux/bitfield.h>
  8#include <linux/debugfs.h>
  9#include <linux/kernel.h>
 10#include <linux/module.h>
 11#include <linux/of.h>
 12#include <linux/of_address.h>
 13#include <linux/of_reserved_mem.h>
 14#include <linux/platform_device.h>
 15#include <linux/seq_file.h>
 16#include <linux/types.h>
 17
 18#include <soc/qcom/cmd-db.h>
 19
 20#define NUM_PRIORITY		2
 21#define MAX_SLV_ID		8
 22#define SLAVE_ID_MASK		0x7
 23#define SLAVE_ID_SHIFT		16
 24#define SLAVE_ID(addr)		FIELD_GET(GENMASK(19, 16), addr)
 25#define VRM_ADDR(addr)		FIELD_GET(GENMASK(19, 4), addr)
 26
 27/**
 28 * struct entry_header: header for each entry in cmddb
 29 *
 30 * @id: resource's identifier
 31 * @priority: unused
 32 * @addr: the address of the resource
 33 * @len: length of the data
 34 * @offset: offset from :@data_offset, start of the data
 35 */
 36struct entry_header {
 37	u8 id[8];
 38	__le32 priority[NUM_PRIORITY];
 39	__le32 addr;
 40	__le16 len;
 41	__le16 offset;
 42};
 43
 44/**
 45 * struct rsc_hdr: resource header information
 46 *
 47 * @slv_id: id for the resource
 48 * @header_offset: entry's header at offset from the end of the cmd_db_header
 49 * @data_offset: entry's data at offset from the end of the cmd_db_header
 50 * @cnt: number of entries for HW type
 51 * @version: MSB is major, LSB is minor
 52 * @reserved: reserved for future use.
 53 */
 54struct rsc_hdr {
 55	__le16 slv_id;
 56	__le16 header_offset;
 57	__le16 data_offset;
 58	__le16 cnt;
 59	__le16 version;
 60	__le16 reserved[3];
 61};
 62
 63/**
 64 * struct cmd_db_header: The DB header information
 65 *
 66 * @version: The cmd db version
 67 * @magic: constant expected in the database
 68 * @header: array of resources
 69 * @checksum: checksum for the header. Unused.
 70 * @reserved: reserved memory
 71 * @data: driver specific data
 72 */
 73struct cmd_db_header {
 74	__le32 version;
 75	u8 magic[4];
 76	struct rsc_hdr header[MAX_SLV_ID];
 77	__le32 checksum;
 78	__le32 reserved;
 79	u8 data[];
 80};
 81
 82/**
 83 * DOC: Description of the Command DB database.
 84 *
 85 * At the start of the command DB memory is the cmd_db_header structure.
 86 * The cmd_db_header holds the version, checksum, magic key as well as an
 87 * array for header for each slave (depicted by the rsc_header). Each h/w
 88 * based accelerator is a 'slave' (shared resource) and has slave id indicating
 89 * the type of accelerator. The rsc_header is the header for such individual
 90 * slaves of a given type. The entries for each of these slaves begin at the
 91 * rsc_hdr.header_offset. In addition each slave could have auxiliary data
 92 * that may be needed by the driver. The data for the slave starts at the
 93 * entry_header.offset to the location pointed to by the rsc_hdr.data_offset.
 94 *
 95 * Drivers have a stringified key to a slave/resource. They can query the slave
 96 * information and get the slave id and the auxiliary data and the length of the
 97 * data. Using this information, they can format the request to be sent to the
 98 * h/w accelerator and request a resource state.
 99 */
100
101static const u8 CMD_DB_MAGIC[] = { 0xdb, 0x30, 0x03, 0x0c };
102
103static bool cmd_db_magic_matches(const struct cmd_db_header *header)
104{
105	const u8 *magic = header->magic;
106
107	return memcmp(magic, CMD_DB_MAGIC, ARRAY_SIZE(CMD_DB_MAGIC)) == 0;
108}
109
110static struct cmd_db_header *cmd_db_header;
111
112static inline const void *rsc_to_entry_header(const struct rsc_hdr *hdr)
113{
114	u16 offset = le16_to_cpu(hdr->header_offset);
115
116	return cmd_db_header->data + offset;
117}
118
119static inline void *
120rsc_offset(const struct rsc_hdr *hdr, const struct entry_header *ent)
121{
122	u16 offset = le16_to_cpu(hdr->data_offset);
123	u16 loffset = le16_to_cpu(ent->offset);
124
125	return cmd_db_header->data + offset + loffset;
126}
127
128/**
129 * cmd_db_ready - Indicates if command DB is available
130 *
131 * Return: 0 on success, errno otherwise
132 */
133int cmd_db_ready(void)
134{
135	if (cmd_db_header == NULL)
136		return -EPROBE_DEFER;
137	else if (!cmd_db_magic_matches(cmd_db_header))
138		return -EINVAL;
139
140	return 0;
141}
142EXPORT_SYMBOL_GPL(cmd_db_ready);
143
144static int cmd_db_get_header(const char *id, const struct entry_header **eh,
145			     const struct rsc_hdr **rh)
146{
147	const struct rsc_hdr *rsc_hdr;
148	const struct entry_header *ent;
149	int ret, i, j;
150	u8 query[sizeof(ent->id)] __nonstring;
151
152	ret = cmd_db_ready();
153	if (ret)
154		return ret;
155
156	strtomem_pad(query, id, 0);
157
158	for (i = 0; i < MAX_SLV_ID; i++) {
159		rsc_hdr = &cmd_db_header->header[i];
160		if (!rsc_hdr->slv_id)
161			break;
162
163		ent = rsc_to_entry_header(rsc_hdr);
164		for (j = 0; j < le16_to_cpu(rsc_hdr->cnt); j++, ent++) {
165			if (memcmp(ent->id, query, sizeof(ent->id)) == 0) {
166				if (eh)
167					*eh = ent;
168				if (rh)
169					*rh = rsc_hdr;
170				return 0;
171			}
172		}
173	}
174
175	return -ENODEV;
176}
177
178/**
179 * cmd_db_read_addr() - Query command db for resource id address.
180 *
181 * @id: resource id to query for address
182 *
183 * Return: resource address on success, 0 on error
184 *
185 * This is used to retrieve resource address based on resource
186 * id.
187 */
188u32 cmd_db_read_addr(const char *id)
189{
190	int ret;
191	const struct entry_header *ent;
192
193	ret = cmd_db_get_header(id, &ent, NULL);
194
195	return ret < 0 ? 0 : le32_to_cpu(ent->addr);
196}
197EXPORT_SYMBOL_GPL(cmd_db_read_addr);
198
199/**
200 * cmd_db_read_aux_data() - Query command db for aux data.
201 *
202 *  @id: Resource to retrieve AUX Data on
203 *  @len: size of data buffer returned
204 *
205 *  Return: pointer to data on success, error pointer otherwise
206 */
207const void *cmd_db_read_aux_data(const char *id, size_t *len)
208{
209	int ret;
210	const struct entry_header *ent;
211	const struct rsc_hdr *rsc_hdr;
212
213	ret = cmd_db_get_header(id, &ent, &rsc_hdr);
214	if (ret)
215		return ERR_PTR(ret);
216
217	if (len)
218		*len = le16_to_cpu(ent->len);
219
220	return rsc_offset(rsc_hdr, ent);
221}
222EXPORT_SYMBOL_GPL(cmd_db_read_aux_data);
223
224/**
225 * cmd_db_match_resource_addr() - Compare if both Resource addresses are same
226 *
227 * @addr1: Resource address to compare
228 * @addr2: Resource address to compare
229 *
230 * Return: true if two addresses refer to the same resource, false otherwise
231 */
232bool cmd_db_match_resource_addr(u32 addr1, u32 addr2)
233{
234	/*
235	 * Each RPMh VRM accelerator resource has 3 or 4 contiguous 4-byte
236	 * aligned addresses associated with it. Ignore the offset to check
237	 * for VRM requests.
238	 */
239	if (addr1 == addr2)
240		return true;
241	else if (SLAVE_ID(addr1) == CMD_DB_HW_VRM && VRM_ADDR(addr1) == VRM_ADDR(addr2))
242		return true;
243
244	return false;
245}
246EXPORT_SYMBOL_GPL(cmd_db_match_resource_addr);
247
248/**
249 * cmd_db_read_slave_id - Get the slave ID for a given resource address
250 *
251 * @id: Resource id to query the DB for version
252 *
253 * Return: cmd_db_hw_type enum on success, CMD_DB_HW_INVALID on error
254 */
255enum cmd_db_hw_type cmd_db_read_slave_id(const char *id)
256{
257	int ret;
258	const struct entry_header *ent;
259	u32 addr;
260
261	ret = cmd_db_get_header(id, &ent, NULL);
262	if (ret < 0)
263		return CMD_DB_HW_INVALID;
264
265	addr = le32_to_cpu(ent->addr);
266	return (addr >> SLAVE_ID_SHIFT) & SLAVE_ID_MASK;
267}
268EXPORT_SYMBOL_GPL(cmd_db_read_slave_id);
269
270#ifdef CONFIG_DEBUG_FS
271static int cmd_db_debugfs_dump(struct seq_file *seq, void *p)
272{
273	int i, j;
274	const struct rsc_hdr *rsc;
275	const struct entry_header *ent;
276	const char *name;
277	u16 len, version;
278	u8 major, minor;
279
280	seq_puts(seq, "Command DB DUMP\n");
281
282	for (i = 0; i < MAX_SLV_ID; i++) {
283		rsc = &cmd_db_header->header[i];
284		if (!rsc->slv_id)
285			break;
286
287		switch (le16_to_cpu(rsc->slv_id)) {
288		case CMD_DB_HW_ARC:
289			name = "ARC";
290			break;
291		case CMD_DB_HW_VRM:
292			name = "VRM";
293			break;
294		case CMD_DB_HW_BCM:
295			name = "BCM";
296			break;
297		default:
298			name = "Unknown";
299			break;
300		}
301
302		version = le16_to_cpu(rsc->version);
303		major = version >> 8;
304		minor = version;
305
306		seq_printf(seq, "Slave %s (v%u.%u)\n", name, major, minor);
307		seq_puts(seq, "-------------------------\n");
308
309		ent = rsc_to_entry_header(rsc);
310		for (j = 0; j < le16_to_cpu(rsc->cnt); j++, ent++) {
311			seq_printf(seq, "0x%05x: %*pEp", le32_to_cpu(ent->addr),
312				   (int)strnlen(ent->id, sizeof(ent->id)), ent->id);
313
314			len = le16_to_cpu(ent->len);
315			if (len) {
316				seq_printf(seq, " [%*ph]",
317					   len, rsc_offset(rsc, ent));
318			}
319			seq_putc(seq, '\n');
320		}
321	}
322
323	return 0;
324}
325
326static int open_cmd_db_debugfs(struct inode *inode, struct file *file)
327{
328	return single_open(file, cmd_db_debugfs_dump, inode->i_private);
329}
330#endif
331
332static const struct file_operations cmd_db_debugfs_ops = {
333#ifdef CONFIG_DEBUG_FS
334	.open = open_cmd_db_debugfs,
335#endif
336	.read = seq_read,
337	.llseek = seq_lseek,
338	.release = single_release,
339};
340
341static int cmd_db_dev_probe(struct platform_device *pdev)
342{
343	struct reserved_mem *rmem;
344	int ret = 0;
345
346	rmem = of_reserved_mem_lookup(pdev->dev.of_node);
347	if (!rmem) {
348		dev_err(&pdev->dev, "failed to acquire memory region\n");
349		return -EINVAL;
350	}
351
352	cmd_db_header = memremap(rmem->base, rmem->size, MEMREMAP_WC);
353	if (!cmd_db_header) {
354		ret = -ENOMEM;
355		cmd_db_header = NULL;
356		return ret;
357	}
358
359	if (!cmd_db_magic_matches(cmd_db_header)) {
360		dev_err(&pdev->dev, "Invalid Command DB Magic\n");
361		return -EINVAL;
362	}
363
364	debugfs_create_file("cmd-db", 0400, NULL, NULL, &cmd_db_debugfs_ops);
365
366	device_set_pm_not_required(&pdev->dev);
367
368	return 0;
369}
370
371static const struct of_device_id cmd_db_match_table[] = {
372	{ .compatible = "qcom,cmd-db" },
373	{ }
374};
375MODULE_DEVICE_TABLE(of, cmd_db_match_table);
376
377static struct platform_driver cmd_db_dev_driver = {
378	.probe  = cmd_db_dev_probe,
379	.driver = {
380		   .name = "cmd-db",
381		   .of_match_table = cmd_db_match_table,
382		   .suppress_bind_attrs = true,
383	},
384};
385
386static int __init cmd_db_device_init(void)
387{
388	return platform_driver_register(&cmd_db_dev_driver);
389}
390core_initcall(cmd_db_device_init);
391
392MODULE_DESCRIPTION("Qualcomm Technologies, Inc. Command DB Driver");
393MODULE_LICENSE("GPL v2");