soc: qcom: smem: Support dynamic item limit

In V12 SMEM, SBL writes SMEM parameter information after the TOC. Use
the SBL provided item count as the max item number.

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>

1 files changed, 45 insertions, 6 deletions

diff --git a/drivers/soc/qcom/smem.c b/drivers/soc/qcom/smem.c
index 6a3134e9c591..19704baa65f4 100644
--- a/drivers/soc/qcom/smem.c
+++ b/drivers/soc/qcom/smem.c
@@ -223,6 +223,24 @@ struct smem_private_entry {
 #define SMEM_PRIVATE_CANARY     0xa5a5
 
 /**
+ * struct smem_info - smem region info located after the table of contents
+ * @magic:      magic number, must be SMEM_INFO_MAGIC
+ * @size:       size of the smem region
+ * @base_addr:  base address of the smem region
+ * @reserved:   for now reserved entry
+ * @num_items:  highest accepted item number
+ */
+struct smem_info {
+        u8 magic[4];
+        __le32 size;
+        __le32 base_addr;
+        __le32 reserved;
+        __le16 num_items;
+};
+
+static const u8 SMEM_INFO_MAGIC[] = { 0x53, 0x49, 0x49, 0x49 }; /* SIII */
+
+/**
  * struct smem_region - representation of a chunk of memory used for smem
  * @aux_base:   identifier of aux_mem base
  * @virt_base:  virtual base address of memory with this aux_mem identifier
@@ -243,6 +261,7 @@ struct smem_region {
  * @partitions: list of pointers to partitions affecting the current
  *              processor/host
  * @cacheline:  list of cacheline sizes for each host
+ * @item_count: max accepted item number
  * @num_regions: number of @regions
  * @regions:    list of the memory regions defining the shared memory
  */
@@ -255,6 +274,7 @@ struct qcom_smem {
         size_t global_cacheline;
         struct smem_partition_header *partitions[SMEM_HOST_COUNT];
         size_t cacheline[SMEM_HOST_COUNT];
+        u32 item_count;
 
         unsigned num_regions;
         struct smem_region regions[0];
@@ -386,9 +406,6 @@ static int qcom_smem_alloc_global(struct qcom_smem *smem,
         struct smem_global_entry *entry;
         struct smem_header *header;
 
-        if (WARN_ON(item >= SMEM_ITEM_COUNT))
-                return -EINVAL;
-
         header = smem->regions[0].virt_base;
         entry = &header->toc[item];
         if (entry->allocated)
@@ -439,6 +456,9 @@ int qcom_smem_alloc(unsigned host, unsigned item, size_t size)
                 return -EINVAL;
         }
 
+        if (WARN_ON(item >= __smem->item_count))
+                return -EINVAL;
+
         ret = hwspin_lock_timeout_irqsave(__smem->hwlock,
                                           HWSPINLOCK_TIMEOUT,
                                           &flags);
@@ -471,9 +491,6 @@ static void *qcom_smem_get_global(struct qcom_smem *smem,
         u32 aux_base;
         unsigned i;
 
-        if (WARN_ON(item >= SMEM_ITEM_COUNT))
-                return ERR_PTR(-EINVAL);
-
         header = smem->regions[0].virt_base;
         entry = &header->toc[item];
         if (!entry->allocated)
@@ -569,6 +586,9 @@ void *qcom_smem_get(unsigned host, unsigned item, size_t *size)
         if (!__smem)
                 return ptr;
 
+        if (WARN_ON(item >= __smem->item_count))
+                return ERR_PTR(-EINVAL);
+
         ret = hwspin_lock_timeout_irqsave(__smem->hwlock,
                                           HWSPINLOCK_TIMEOUT,
                                           &flags);
@@ -656,6 +676,22 @@ static struct smem_ptable *qcom_smem_get_ptable(struct qcom_smem *smem)
         return ptable;
 }
 
+static u32 qcom_smem_get_item_count(struct qcom_smem *smem)
+{
+        struct smem_ptable *ptable;
+        struct smem_info *info;
+
+        ptable = qcom_smem_get_ptable(smem);
+        if (IS_ERR_OR_NULL(ptable))
+                return SMEM_ITEM_COUNT;
+
+        info = (struct smem_info *)&ptable->entry[ptable->num_entries];
+        if (memcmp(info->magic, SMEM_INFO_MAGIC, sizeof(info->magic)))
+                return SMEM_ITEM_COUNT;
+
+        return le16_to_cpu(info->num_items);
+}
+
 static int qcom_smem_set_global_partition(struct qcom_smem *smem)
 {
         struct smem_partition_header *header;
@@ -883,7 +919,10 @@ static int qcom_smem_probe(struct platform_device *pdev)
                 ret = qcom_smem_set_global_partition(smem);
                 if (ret < 0)
                         return ret;
+                smem->item_count = qcom_smem_get_item_count(smem);
+                break;
         case SMEM_GLOBAL_HEAP_VERSION:
+                smem->item_count = SMEM_ITEM_COUNT;
                 break;
         default:
                 dev_err(&pdev->dev, "Unsupported SMEM version 0x%x\n", version);