soc: qcom: smem: Support global partition

SMEM V12 creates a global partition to allocate global smem items from
instead of a global heap. The global partition has the same structure as
a private partition.

Signed-off-by: Chris Lew <clew@codeaurora.org>
Acked-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Andy Gross <andy.gross@linaro.org>

Author: Chris Lew

drivers/soc/qcom/smem.c

@@ -55,6 +55,10 @@
  * is hence the region between the cached and non-cached offsets. The header of
  * cached items comes after the data.
  *
+ * Version 12 (SMEM_GLOBAL_PART_VERSION) changes the item alloc/get procedure
+ * for the global heap. A new global partition is created from the global heap
+ * region with partition type (SMEM_GLOBAL_HOST) and the max smem item count is
+ * set by the bootloader.
  *
  * To synchronize allocations in the shared memory heaps a remote spinlock must
  * be held - currently lock number 3 of the sfpb or tcsr is used for this on all
@@ -68,7 +72,8 @@
  * version is a valid version as a sanity check.
  */
 #define SMEM_MASTER_SBL_VERSION_INDEX	7
-#define SMEM_EXPECTED_VERSION		11
+#define SMEM_GLOBAL_HEAP_VERSION	11
+#define SMEM_GLOBAL_PART_VERSION	12
 
 /*
  * The first 8 items are only to be allocated by the boot loader while
@@ -82,6 +87,9 @@
 /* Processor/host identifier for the application processor */
 #define SMEM_HOST_APPS		0
 
+/* Processor/host identifier for the global partition */
+#define SMEM_GLOBAL_HOST	0xfffe
+
 /* Max number of processors/hosts in a system */
 #define SMEM_HOST_COUNT		9
 
@@ -230,6 +238,8 @@ struct smem_region {
  * struct qcom_smem - device data for the smem device
  * @dev:	device pointer
  * @hwlock:	reference to a hwspinlock
+ * @global_partition:	pointer to global partition when in use
+ * @global_cacheline:	cacheline size for global partition
  * @partitions:	list of pointers to partitions affecting the current
  *		processor/host
  * @cacheline:	list of cacheline sizes for each host
@@ -241,6 +251,8 @@ struct qcom_smem {
 
 	struct hwspinlock *hwlock;
 
+	struct smem_partition_header *global_partition;
+	size_t global_cacheline;
 	struct smem_partition_header *partitions[SMEM_HOST_COUNT];
 	size_t cacheline[SMEM_HOST_COUNT];
 
@@ -317,25 +329,23 @@ static struct qcom_smem *__smem;
 #define HWSPINLOCK_TIMEOUT	1000
 
 static int qcom_smem_alloc_private(struct qcom_smem *smem,
-				   unsigned host,
+				   struct smem_partition_header *phdr,
 				   unsigned item,
 				   size_t size)
 {
-	struct smem_partition_header *phdr;
 	struct smem_private_entry *hdr, *end;
 	size_t alloc_size;
 	void *cached;
 
-	phdr = smem->partitions[host];
 	hdr = phdr_to_first_uncached_entry(phdr);
 	end = phdr_to_last_uncached_entry(phdr);
 	cached = phdr_to_last_cached_entry(phdr);
 
 	while (hdr < end) {
 		if (hdr->canary != SMEM_PRIVATE_CANARY) {
 			dev_err(smem->dev,
-				"Found invalid canary in host %d partition\n",
-				host);
+				"Found invalid canary in hosts %d:%d partition\n",
+				phdr->host0, phdr->host1);
 			return -EINVAL;
 		}
 
@@ -373,8 +383,8 @@ static int qcom_smem_alloc_global(struct qcom_smem *smem,
 				  unsigned item,
 				  size_t size)
 {
-	struct smem_header *header;
 	struct smem_global_entry *entry;
+	struct smem_header *header;
 
 	if (WARN_ON(item >= SMEM_ITEM_COUNT))
 		return -EINVAL;
@@ -416,6 +426,7 @@ static int qcom_smem_alloc_global(struct qcom_smem *smem,
  */
 int qcom_smem_alloc(unsigned host, unsigned item, size_t size)
 {
+	struct smem_partition_header *phdr;
 	unsigned long flags;
 	int ret;
 
@@ -434,10 +445,15 @@ int qcom_smem_alloc(unsigned host, unsigned item, size_t size)
 	if (ret)
 		return ret;
 
-	if (host < SMEM_HOST_COUNT && __smem->partitions[host])
-		ret = qcom_smem_alloc_private(__smem, host, item, size);
-	else
+	if (host < SMEM_HOST_COUNT && __smem->partitions[host]) {
+		phdr = __smem->partitions[host];
+		ret = qcom_smem_alloc_private(__smem, phdr, item, size);
+	} else if (__smem->global_partition) {
+		phdr = __smem->global_partition;
+		ret = qcom_smem_alloc_private(__smem, phdr, item, size);
+	} else {
 		ret = qcom_smem_alloc_global(__smem, item, size);
+	}
 
 	hwspin_unlock_irqrestore(__smem->hwlock, &flags);
 
@@ -479,16 +495,12 @@ static void *qcom_smem_get_global(struct qcom_smem *smem,
 }
 
 static void *qcom_smem_get_private(struct qcom_smem *smem,
-				   unsigned host,
+				   struct smem_partition_header *phdr,
+				   size_t cacheline,
 				   unsigned item,
 				   size_t *size)
 {
-	struct smem_partition_header *phdr;
 	struct smem_private_entry *e, *end;
-	size_t cacheline;
-
-	phdr = smem->partitions[host];
-	cacheline = smem->cacheline[host];
 
 	e = phdr_to_first_uncached_entry(phdr);
 	end = phdr_to_last_uncached_entry(phdr);
@@ -531,7 +543,8 @@ static void *qcom_smem_get_private(struct qcom_smem *smem,
 	return ERR_PTR(-ENOENT);
 
 invalid_canary:
-	dev_err(smem->dev, "Found invalid canary in host %d partition\n", host);
+	dev_err(smem->dev, "Found invalid canary in hosts %d:%d partition\n",
+			phdr->host0, phdr->host1);
 
 	return ERR_PTR(-EINVAL);
 }
@@ -547,7 +560,9 @@ static void *qcom_smem_get_private(struct qcom_smem *smem,
  */
 void *qcom_smem_get(unsigned host, unsigned item, size_t *size)
 {
+	struct smem_partition_header *phdr;
 	unsigned long flags;
+	size_t cacheln;
 	int ret;
 	void *ptr = ERR_PTR(-EPROBE_DEFER);
 
@@ -560,10 +575,17 @@ void *qcom_smem_get(unsigned host, unsigned item, size_t *size)
 	if (ret)
 		return ERR_PTR(ret);
 
-	if (host < SMEM_HOST_COUNT && __smem->partitions[host])
-		ptr = qcom_smem_get_private(__smem, host, item, size);
-	else
+	if (host < SMEM_HOST_COUNT && __smem->partitions[host]) {
+		phdr = __smem->partitions[host];
+		cacheln = __smem->cacheline[host];
+		ptr = qcom_smem_get_private(__smem, phdr, cacheln, item, size);
+	} else if (__smem->global_partition) {
+		phdr = __smem->global_partition;
+		cacheln = __smem->global_cacheline;
+		ptr = qcom_smem_get_private(__smem, phdr, cacheln, item, size);
+	} else {
 		ptr = qcom_smem_get_global(__smem, item, size);
+	}
 
 	hwspin_unlock_irqrestore(__smem->hwlock, &flags);
 
@@ -592,6 +614,10 @@ int qcom_smem_get_free_space(unsigned host)
 		phdr = __smem->partitions[host];
 		ret = le32_to_cpu(phdr->offset_free_cached) -
 		      le32_to_cpu(phdr->offset_free_uncached);
+	} else if (__smem->global_partition) {
+		phdr = __smem->global_partition;
+		ret = le32_to_cpu(phdr->offset_free_cached) -
+		      le32_to_cpu(phdr->offset_free_uncached);
 	} else {
 		header = __smem->regions[0].virt_base;
 		ret = le32_to_cpu(header->available);
@@ -612,27 +638,106 @@ static int qcom_smem_get_sbl_version(struct qcom_smem *smem)
 	return le32_to_cpu(versions[SMEM_MASTER_SBL_VERSION_INDEX]);
 }
 
-static int qcom_smem_enumerate_partitions(struct qcom_smem *smem,
-					  unsigned local_host)
+static struct smem_ptable *qcom_smem_get_ptable(struct qcom_smem *smem)
 {
-	struct smem_partition_header *header;
-	struct smem_ptable_entry *entry;
 	struct smem_ptable *ptable;
-	unsigned remote_host;
-	u32 version, host0, host1;
-	int i;
+	u32 version;
 
 	ptable = smem->regions[0].virt_base + smem->regions[0].size - SZ_4K;
 	if (memcmp(ptable->magic, SMEM_PTABLE_MAGIC, sizeof(ptable->magic)))
-		return 0;
+		return ERR_PTR(-ENOENT);
 
 	version = le32_to_cpu(ptable->version);
 	if (version != 1) {
 		dev_err(smem->dev,
 			"Unsupported partition header version %d\n", version);
+		return ERR_PTR(-EINVAL);
+	}
+	return ptable;
+}
+
+static int qcom_smem_set_global_partition(struct qcom_smem *smem)
+{
+	struct smem_partition_header *header;
+	struct smem_ptable_entry *entry = NULL;
+	struct smem_ptable *ptable;
+	u32 host0, host1, size;
+	int i;
+
+	ptable = qcom_smem_get_ptable(smem);
+	if (IS_ERR(ptable))
+		return PTR_ERR(ptable);
+
+	for (i = 0; i < le32_to_cpu(ptable->num_entries); i++) {
+		entry = &ptable->entry[i];
+		host0 = le16_to_cpu(entry->host0);
+		host1 = le16_to_cpu(entry->host1);
+
+		if (host0 == SMEM_GLOBAL_HOST && host0 == host1)
+			break;
+	}
+
+	if (!entry) {
+		dev_err(smem->dev, "Missing entry for global partition\n");
+		return -EINVAL;
+	}
+
+	if (!le32_to_cpu(entry->offset) || !le32_to_cpu(entry->size)) {
+		dev_err(smem->dev, "Invalid entry for global partition\n");
+		return -EINVAL;
+	}
+
+	if (smem->global_partition) {
+		dev_err(smem->dev, "Already found the global partition\n");
+		return -EINVAL;
+	}
+
+	header = smem->regions[0].virt_base + le32_to_cpu(entry->offset);
+	host0 = le16_to_cpu(header->host0);
+	host1 = le16_to_cpu(header->host1);
+
+	if (memcmp(header->magic, SMEM_PART_MAGIC, sizeof(header->magic))) {
+		dev_err(smem->dev, "Global partition has invalid magic\n");
+		return -EINVAL;
+	}
+
+	if (host0 != SMEM_GLOBAL_HOST && host1 != SMEM_GLOBAL_HOST) {
+		dev_err(smem->dev, "Global partition hosts are invalid\n");
+		return -EINVAL;
+	}
+
+	if (le32_to_cpu(header->size) != le32_to_cpu(entry->size)) {
+		dev_err(smem->dev, "Global partition has invalid size\n");
 		return -EINVAL;
 	}
 
+	size = le32_to_cpu(header->offset_free_uncached);
+	if (size > le32_to_cpu(header->size)) {
+		dev_err(smem->dev,
+			"Global partition has invalid free pointer\n");
+		return -EINVAL;
+	}
+
+	smem->global_partition = header;
+	smem->global_cacheline = le32_to_cpu(entry->cacheline);
+
+	return 0;
+}
+
+static int qcom_smem_enumerate_partitions(struct qcom_smem *smem,
+					  unsigned int local_host)
+{
+	struct smem_partition_header *header;
+	struct smem_ptable_entry *entry;
+	struct smem_ptable *ptable;
+	unsigned int remote_host;
+	u32 host0, host1;
+	int i;
+
+	ptable = qcom_smem_get_ptable(smem);
+	if (IS_ERR(ptable))
+		return PTR_ERR(ptable);
+
 	for (i = 0; i < le32_to_cpu(ptable->num_entries); i++) {
 		entry = &ptable->entry[i];
 		host0 = le16_to_cpu(entry->host0);
@@ -773,13 +878,20 @@ static int qcom_smem_probe(struct platform_device *pdev)
 	}
 
 	version = qcom_smem_get_sbl_version(smem);
-	if (version >> 16 != SMEM_EXPECTED_VERSION) {
+	switch (version >> 16) {
+	case SMEM_GLOBAL_PART_VERSION:
+		ret = qcom_smem_set_global_partition(smem);
+		if (ret < 0)
+			return ret;
+	case SMEM_GLOBAL_HEAP_VERSION:
+		break;
+	default:
 		dev_err(&pdev->dev, "Unsupported SMEM version 0x%x\n", version);
 		return -EINVAL;
 	}
 
 	ret = qcom_smem_enumerate_partitions(smem, SMEM_HOST_APPS);
-	if (ret < 0)
+	if (ret < 0 && ret != -ENOENT)
 		return ret;
 
 	hwlock_id = of_hwspin_lock_get_id(pdev->dev.of_node, 0);