2 * Copyright (c) 2015, Sony Mobile Communications AB.
3 * Copyright (c) 2012-2013, The Linux Foundation. All rights reserved.
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License version 2 and
7 * only version 2 as published by the Free Software Foundation.
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
15 #include <linux/hwspinlock.h>
17 #include <linux/module.h>
19 #include <linux/of_address.h>
20 #include <linux/platform_device.h>
21 #include <linux/slab.h>
22 #include <linux/soc/qcom/smem.h>
23 #include <linux/debugfs.h>
26 * The Qualcomm shared memory system is a allocate only heap structure that
27 * consists of one of more memory areas that can be accessed by the processors
30 * All systems contains a global heap, accessible by all processors in the SoC,
31 * with a table of contents data structure (@smem_header) at the beginning of
32 * the main shared memory block.
34 * The global header contains meta data for allocations as well as a fixed list
35 * of 512 entries (@smem_global_entry) that can be initialized to reference
36 * parts of the shared memory space.
39 * In addition to this global heap a set of "private" heaps can be set up at
40 * boot time with access restrictions so that only certain processor pairs can
43 * These partitions are referenced from an optional partition table
44 * (@smem_ptable), that is found 4kB from the end of the main smem region. The
45 * partition table entries (@smem_ptable_entry) lists the involved processors
46 * (or hosts) and their location in the main shared memory region.
48 * Each partition starts with a header (@smem_partition_header) that identifies
49 * the partition and holds properties for the two internal memory regions. The
50 * two regions are cached and non-cached memory respectively. Each region
51 * contain a link list of allocation headers (@smem_private_entry) followed by
54 * Items in the non-cached region are allocated from the start of the partition
55 * while items in the cached region are allocated from the end. The free area
56 * is hence the region between the cached and non-cached offsets.
59 * To synchronize allocations in the shared memory heaps a remote spinlock must
60 * be held - currently lock number 3 of the sfpb or tcsr is used for this on all
66 * Item 3 of the global heap contains an array of versions for the various
67 * software components in the SoC. We verify that the boot loader version is
68 * what the expected version (SMEM_EXPECTED_VERSION) as a sanity check.
70 #define SMEM_ITEM_VERSION 3
71 #define SMEM_MASTER_SBL_VERSION_INDEX 7
72 #define SMEM_EXPECTED_VERSION 11
75 * The first 8 items are only to be allocated by the boot loader while
76 * initializing the heap.
78 #define SMEM_ITEM_LAST_FIXED 8
80 /* Highest accepted item number, for both global and private heaps */
81 #define SMEM_ITEM_COUNT 512
83 /* Processor/host identifier for the application processor */
84 #define SMEM_HOST_APPS 0
86 /* Max number of processors/hosts in a system */
87 #define SMEM_HOST_COUNT 9
89 #define SMEM_HEAP_INFO 1
92 * struct smem_proc_comm - proc_comm communication struct (legacy)
93 * @command: current command to be executed
94 * @status: status of the currently requested command
95 * @params: parameters to the command
97 struct smem_proc_comm {
104 * struct smem_global_entry - entry to reference smem items on the heap
105 * @allocated: boolean to indicate if this entry is used
106 * @offset: offset to the allocated space
107 * @size: size of the allocated space, 8 byte aligned
108 * @aux_base: base address for the memory region used by this unit, or 0 for
109 * the default region. bits 0,1 are reserved
111 struct smem_global_entry {
115 __le32 aux_base; /* bits 1:0 reserved */
117 #define AUX_BASE_MASK 0xfffffffc
120 * struct smem_header - header found in beginning of primary smem region
121 * @proc_comm: proc_comm communication interface (legacy)
122 * @version: array of versions for the various subsystems
123 * @initialized: boolean to indicate that smem is initialized
124 * @free_offset: index of the first unallocated byte in smem
125 * @available: number of bytes available for allocation
126 * @reserved: reserved field, must be 0
127 * toc: array of references to items
130 struct smem_proc_comm proc_comm[4];
136 struct smem_global_entry toc[SMEM_ITEM_COUNT];
140 * struct smem_ptable_entry - one entry in the @smem_ptable list
141 * @offset: offset, within the main shared memory region, of the partition
142 * @size: size of the partition
143 * @flags: flags for the partition (currently unused)
144 * @host0: first processor/host with access to this partition
145 * @host1: second processor/host with access to this partition
146 * @reserved: reserved entries for later use
148 struct smem_ptable_entry {
158 * struct smem_ptable - partition table for the private partitions
159 * @magic: magic number, must be SMEM_PTABLE_MAGIC
160 * @version: version of the partition table
161 * @num_entries: number of partitions in the table
162 * @reserved: for now reserved entries
163 * @entry: list of @smem_ptable_entry for the @num_entries partitions
170 struct smem_ptable_entry entry[];
173 static const u8 SMEM_PTABLE_MAGIC[] = { 0x24, 0x54, 0x4f, 0x43 }; /* "$TOC" */
176 * struct smem_partition_header - header of the partitions
177 * @magic: magic number, must be SMEM_PART_MAGIC
178 * @host0: first processor/host with access to this partition
179 * @host1: second processor/host with access to this partition
180 * @size: size of the partition
181 * @offset_free_uncached: offset to the first free byte of uncached memory in
183 * @offset_free_cached: offset to the first free byte of cached memory in this
185 * @reserved: for now reserved entries
187 struct smem_partition_header {
192 __le32 offset_free_uncached;
193 __le32 offset_free_cached;
197 static const u8 SMEM_PART_MAGIC[] = { 0x24, 0x50, 0x52, 0x54 };
200 * struct smem_private_entry - header of each item in the private partition
201 * @canary: magic number, must be SMEM_PRIVATE_CANARY
202 * @item: identifying number of the smem item
203 * @size: size of the data, including padding bytes
204 * @padding_data: number of bytes of padding of data
205 * @padding_hdr: number of bytes of padding between the header and the data
206 * @reserved: for now reserved entry
208 struct smem_private_entry {
209 u16 canary; /* bytes are the same so no swapping needed */
211 __le32 size; /* includes padding bytes */
216 #define SMEM_PRIVATE_CANARY 0xa5a5
219 * struct smem_region - representation of a chunk of memory used for smem
220 * @aux_base: identifier of aux_mem base
221 * @virt_base: virtual base address of memory with this aux_mem identifier
222 * @size: size of the memory region
226 void __iomem *virt_base;
231 * struct qcom_smem - device data for the smem device
232 * @dev: device pointer
233 * @hwlock: reference to a hwspinlock
234 * @partitions: list of pointers to partitions affecting the current
236 * @num_regions: number of @regions
237 * @regions: list of the memory regions defining the shared memory
242 struct hwspinlock *hwlock;
244 struct smem_partition_header *partitions[SMEM_HOST_COUNT];
249 unsigned num_regions;
250 struct smem_region regions[0];
253 static struct smem_private_entry *
254 phdr_to_last_private_entry(struct smem_partition_header *phdr)
258 return p + le32_to_cpu(phdr->offset_free_uncached);
261 static void *phdr_to_first_cached_entry(struct smem_partition_header *phdr)
265 return p + le32_to_cpu(phdr->offset_free_cached);
268 static struct smem_private_entry *
269 phdr_to_first_private_entry(struct smem_partition_header *phdr)
273 return p + sizeof(*phdr);
276 static struct smem_private_entry *
277 private_entry_next(struct smem_private_entry *e)
281 return p + sizeof(*e) + le16_to_cpu(e->padding_hdr) +
282 le32_to_cpu(e->size);
285 static void *entry_to_item(struct smem_private_entry *e)
289 return p + sizeof(*e) + le16_to_cpu(e->padding_hdr);
292 /* Pointer to the one and only smem handle */
293 static struct qcom_smem *__smem;
295 /* Timeout (ms) for the trylock of remote spinlocks */
296 #define HWSPINLOCK_TIMEOUT 1000
298 static int qcom_smem_alloc_private(struct qcom_smem *smem,
303 struct smem_partition_header *phdr;
304 struct smem_private_entry *hdr, *end;
308 phdr = smem->partitions[host];
309 hdr = phdr_to_first_private_entry(phdr);
310 end = phdr_to_last_private_entry(phdr);
311 cached = phdr_to_first_cached_entry(phdr);
314 if (hdr->canary != SMEM_PRIVATE_CANARY) {
316 "Found invalid canary in host %d partition\n",
321 if (le16_to_cpu(hdr->item) == item)
324 hdr = private_entry_next(hdr);
327 /* Check that we don't grow into the cached region */
328 alloc_size = sizeof(*hdr) + ALIGN(size, 8);
329 if ((void *)hdr + alloc_size >= cached) {
330 dev_err(smem->dev, "Out of memory\n");
334 hdr->canary = SMEM_PRIVATE_CANARY;
335 hdr->item = cpu_to_le16(item);
336 hdr->size = cpu_to_le32(ALIGN(size, 8));
337 hdr->padding_data = cpu_to_le16(le32_to_cpu(hdr->size) - size);
338 hdr->padding_hdr = 0;
341 * Ensure the header is written before we advance the free offset, so
342 * that remote processors that does not take the remote spinlock still
343 * gets a consistent view of the linked list.
346 le32_add_cpu(&phdr->offset_free_uncached, alloc_size);
351 static int qcom_smem_alloc_global(struct qcom_smem *smem,
355 struct smem_header *header;
356 struct smem_global_entry *entry;
358 if (WARN_ON(item >= SMEM_ITEM_COUNT))
361 header = smem->regions[0].virt_base;
362 entry = &header->toc[item];
363 if (entry->allocated)
366 size = ALIGN(size, 8);
367 if (WARN_ON(size > le32_to_cpu(header->available)))
370 entry->offset = header->free_offset;
371 entry->size = cpu_to_le32(size);
374 * Ensure the header is consistent before we mark the item allocated,
375 * so that remote processors will get a consistent view of the item
376 * even though they do not take the spinlock on read.
379 entry->allocated = cpu_to_le32(1);
381 le32_add_cpu(&header->free_offset, size);
382 le32_add_cpu(&header->available, -size);
388 * qcom_smem_alloc() - allocate space for a smem item
389 * @host: remote processor id, or -1
390 * @item: smem item handle
391 * @size: number of bytes to be allocated
393 * Allocate space for a given smem item of size @size, given that the item is
396 int qcom_smem_alloc(unsigned host, unsigned item, size_t size)
402 return -EPROBE_DEFER;
404 if (item < SMEM_ITEM_LAST_FIXED) {
406 "Rejecting allocation of static entry %d\n", item);
410 ret = hwspin_lock_timeout_irqsave(__smem->hwlock,
416 if (host < SMEM_HOST_COUNT && __smem->partitions[host])
417 ret = qcom_smem_alloc_private(__smem, host, item, size);
419 ret = qcom_smem_alloc_global(__smem, item, size);
421 hwspin_unlock_irqrestore(__smem->hwlock, &flags);
425 EXPORT_SYMBOL(qcom_smem_alloc);
427 static void *qcom_smem_get_global(struct qcom_smem *smem,
431 struct smem_header *header;
432 struct smem_region *area;
433 struct smem_global_entry *entry;
437 if (WARN_ON(item >= SMEM_ITEM_COUNT))
438 return ERR_PTR(-EINVAL);
440 header = smem->regions[0].virt_base;
441 entry = &header->toc[item];
442 if (!entry->allocated)
443 return ERR_PTR(-ENXIO);
445 aux_base = le32_to_cpu(entry->aux_base) & AUX_BASE_MASK;
447 for (i = 0; i < smem->num_regions; i++) {
448 area = &smem->regions[i];
450 if (area->aux_base == aux_base || !aux_base) {
452 *size = le32_to_cpu(entry->size);
453 return area->virt_base + le32_to_cpu(entry->offset);
457 return ERR_PTR(-ENOENT);
460 static void *qcom_smem_get_private(struct qcom_smem *smem,
465 struct smem_partition_header *phdr;
466 struct smem_private_entry *e, *end;
468 phdr = smem->partitions[host];
469 e = phdr_to_first_private_entry(phdr);
470 end = phdr_to_last_private_entry(phdr);
473 if (e->canary != SMEM_PRIVATE_CANARY) {
475 "Found invalid canary in host %d partition\n",
477 return ERR_PTR(-EINVAL);
480 if (le16_to_cpu(e->item) == item) {
482 *size = le32_to_cpu(e->size) -
483 le16_to_cpu(e->padding_data);
485 return entry_to_item(e);
488 e = private_entry_next(e);
491 return ERR_PTR(-ENOENT);
495 * qcom_smem_get() - resolve ptr of size of a smem item
496 * @host: the remote processor, or -1
497 * @item: smem item handle
498 * @size: pointer to be filled out with size of the item
500 * Looks up smem item and returns pointer to it. Size of smem
501 * item is returned in @size.
503 void *qcom_smem_get(unsigned host, unsigned item, size_t *size)
507 void *ptr = ERR_PTR(-EPROBE_DEFER);
512 ret = hwspin_lock_timeout_irqsave(__smem->hwlock,
518 if (host < SMEM_HOST_COUNT && __smem->partitions[host])
519 ptr = qcom_smem_get_private(__smem, host, item, size);
521 ptr = qcom_smem_get_global(__smem, item, size);
523 hwspin_unlock_irqrestore(__smem->hwlock, &flags);
528 EXPORT_SYMBOL(qcom_smem_get);
531 * qcom_smem_get_free_space() - retrieve amount of free space in a partition
532 * @host: the remote processor identifying a partition, or -1
534 * To be used by smem clients as a quick way to determine if any new
535 * allocations has been made.
537 int qcom_smem_get_free_space(unsigned host)
539 struct smem_partition_header *phdr;
540 struct smem_header *header;
544 return -EPROBE_DEFER;
546 if (host < SMEM_HOST_COUNT && __smem->partitions[host]) {
547 phdr = __smem->partitions[host];
548 ret = le32_to_cpu(phdr->offset_free_cached) -
549 le32_to_cpu(phdr->offset_free_uncached);
551 header = __smem->regions[0].virt_base;
552 ret = le32_to_cpu(header->available);
557 EXPORT_SYMBOL(qcom_smem_get_free_space);
559 static int qcom_smem_get_sbl_version(struct qcom_smem *smem)
564 versions = qcom_smem_get_global(smem, SMEM_ITEM_VERSION, &size);
565 if (IS_ERR(versions)) {
566 dev_err(smem->dev, "Unable to read the version item\n");
570 if (size < sizeof(unsigned) * SMEM_MASTER_SBL_VERSION_INDEX) {
571 dev_err(smem->dev, "Version item is too small\n");
575 return le32_to_cpu(versions[SMEM_MASTER_SBL_VERSION_INDEX]);
578 static int qcom_smem_enumerate_partitions(struct qcom_smem *smem,
581 struct smem_partition_header *header;
582 struct smem_ptable_entry *entry;
583 struct smem_ptable *ptable;
584 unsigned remote_host;
585 u32 version, host0, host1;
588 ptable = smem->regions[0].virt_base + smem->regions[0].size - SZ_4K;
589 if (memcmp(ptable->magic, SMEM_PTABLE_MAGIC, sizeof(ptable->magic)))
592 version = le32_to_cpu(ptable->version);
595 "Unsupported partition header version %d\n", version);
599 for (i = 0; i < le32_to_cpu(ptable->num_entries); i++) {
600 entry = &ptable->entry[i];
601 host0 = le16_to_cpu(entry->host0);
602 host1 = le16_to_cpu(entry->host1);
604 if (host0 != local_host && host1 != local_host)
607 if (!le32_to_cpu(entry->offset))
610 if (!le32_to_cpu(entry->size))
613 if (host0 == local_host)
618 if (remote_host >= SMEM_HOST_COUNT) {
620 "Invalid remote host %d\n",
625 if (smem->partitions[remote_host]) {
627 "Already found a partition for host %d\n",
632 header = smem->regions[0].virt_base + le32_to_cpu(entry->offset);
633 host0 = le16_to_cpu(header->host0);
634 host1 = le16_to_cpu(header->host1);
636 if (memcmp(header->magic, SMEM_PART_MAGIC,
637 sizeof(header->magic))) {
639 "Partition %d has invalid magic\n", i);
643 if (host0 != local_host && host1 != local_host) {
645 "Partition %d hosts are invalid\n", i);
649 if (host0 != remote_host && host1 != remote_host) {
651 "Partition %d hosts are invalid\n", i);
655 if (header->size != entry->size) {
657 "Partition %d has invalid size\n", i);
661 if (le32_to_cpu(header->offset_free_uncached) > le32_to_cpu(header->size)) {
663 "Partition %d has invalid free pointer\n", i);
667 smem->partitions[remote_host] = header;
673 static int qcom_smem_map_memory(struct qcom_smem *smem, struct device *dev,
674 const char *name, int i)
676 struct device_node *np;
680 np = of_parse_phandle(dev->of_node, name, 0);
682 dev_err(dev, "No %s specified\n", name);
686 ret = of_address_to_resource(np, 0, &r);
691 smem->regions[i].aux_base = (u32)r.start;
692 smem->regions[i].size = resource_size(&r);
693 smem->regions[i].virt_base = devm_ioremap_nocache(dev, r.start,
695 if (!smem->regions[i].virt_base)
701 static void smem_debug_read_mem(struct seq_file *s)
708 info = qcom_smem_get(QCOM_SMEM_HOST_ANY, SMEM_HEAP_INFO, &size);
711 seq_printf(s, "Can't get global heap information pool\n");
713 seq_printf(s, "global heap\n");
714 seq_printf(s, " initialized: %d offset: %08x avail: %08x\n",
715 info[0], info[1], info[2]);
717 for (i = 0; i < 512; i++) {
718 info = qcom_smem_get(QCOM_SMEM_HOST_ANY, i, &size);
722 seq_printf(s, " [%d]: p: %p s: %li\n", i, info,
727 seq_printf(s, "\nSecure partitions accessible from APPS:\n");
729 ret = hwspin_lock_timeout_irqsave(__smem->hwlock,
733 for (i = 0; i < SMEM_HOST_COUNT; i++) {
734 struct smem_partition_header *part_hdr = __smem->partitions[i];
740 if (part_hdr->magic != SMEM_PART_MAGIC) {
741 seq_printf(s, " part[%d]: incorrect magic\n", i);
745 seq_printf(s, " part[%d]: (%d <-> %d) size: %d off: %08x\n",
746 i, part_hdr->host0, part_hdr->host1, part_hdr->size,
747 part_hdr->offset_free_uncached);
749 p = (void *)part_hdr + sizeof(*part_hdr);
750 while (p < (void *)part_hdr + part_hdr->offset_free_uncached) {
751 struct smem_private_entry *entry = p;
754 " [%d]: %s size: %d pd: %d\n",
756 (entry->canary == SMEM_PRIVATE_CANARY) ?
759 entry->padding_data);
761 p += sizeof(*entry) + entry->padding_hdr + entry->size;
765 hwspin_unlock_irqrestore(__smem->hwlock, &flags);
768 static void smem_debug_read_version(struct seq_file *s)
770 seq_printf(s, "SBL version: %08x\n", __smem->version >> 16);
773 static int debugfs_show(struct seq_file *s, void *data)
775 void (*show)(struct seq_file *) = s->private;
782 static int smem_debug_open(struct inode *inode, struct file *file)
784 return single_open(file, debugfs_show, inode->i_private);
788 static const struct file_operations smem_debug_ops = {
789 .open = smem_debug_open,
790 .release = single_release,
797 static int qcom_smem_probe(struct platform_device *pdev)
799 struct smem_header *header;
800 struct qcom_smem *smem;
807 if (of_find_property(pdev->dev.of_node, "qcom,rpm-msg-ram", NULL))
810 array_size = num_regions * sizeof(struct smem_region);
811 smem = devm_kzalloc(&pdev->dev, sizeof(*smem) + array_size, GFP_KERNEL);
815 smem->dev = &pdev->dev;
816 smem->num_regions = num_regions;
818 ret = qcom_smem_map_memory(smem, &pdev->dev, "memory-region", 0);
822 if (num_regions > 1 && (ret = qcom_smem_map_memory(smem, &pdev->dev,
823 "qcom,rpm-msg-ram", 1)))
826 header = smem->regions[0].virt_base;
827 if (le32_to_cpu(header->initialized) != 1 ||
828 le32_to_cpu(header->reserved)) {
829 dev_err(&pdev->dev, "SMEM is not initialized by SBL\n");
833 smem->version = qcom_smem_get_sbl_version(smem);
834 if (smem->version >> 16 != SMEM_EXPECTED_VERSION) {
835 dev_err(&pdev->dev, "Unsupported SMEM version 0x%x\n", smem->version);
839 ret = qcom_smem_enumerate_partitions(smem, SMEM_HOST_APPS);
843 hwlock_id = of_hwspin_lock_get_id(pdev->dev.of_node, 0);
845 dev_err(&pdev->dev, "failed to retrieve hwlock\n");
849 smem->hwlock = hwspin_lock_request_specific(hwlock_id);
855 /* setup debugfs information */
856 __smem->dent = debugfs_create_dir("smem", 0);
857 if (IS_ERR(__smem->dent))
858 dev_info(smem->dev, "unable to create debugfs\n");
860 if (!debugfs_create_file("mem", 0444, __smem->dent, smem_debug_read_mem, &smem_debug_ops))
861 dev_err(smem->dev, "couldnt create mem file\n");
862 if (!debugfs_create_file("version", 0444, __smem->dent, smem_debug_read_version,
864 dev_err(smem->dev, "couldnt create mem file\n");
869 static int qcom_smem_remove(struct platform_device *pdev)
871 hwspin_lock_free(__smem->hwlock);
877 static const struct of_device_id qcom_smem_of_match[] = {
878 { .compatible = "qcom,smem" },
881 MODULE_DEVICE_TABLE(of, qcom_smem_of_match);
883 static struct platform_driver qcom_smem_driver = {
884 .probe = qcom_smem_probe,
885 .remove = qcom_smem_remove,
888 .of_match_table = qcom_smem_of_match,
889 .suppress_bind_attrs = true,
893 static int __init qcom_smem_init(void)
895 return platform_driver_register(&qcom_smem_driver);
897 arch_initcall(qcom_smem_init);
899 static void __exit qcom_smem_exit(void)
901 platform_driver_unregister(&qcom_smem_driver);
903 module_exit(qcom_smem_exit)
905 MODULE_AUTHOR("Bjorn Andersson <bjorn.andersson@sonymobile.com>");
906 MODULE_DESCRIPTION("Qualcomm Shared Memory Manager");
907 MODULE_LICENSE("GPL v2");