ACPI / PPTT: Add acpi_pptt_cache_v1_full to use pptt cache as one structure

In actbl2.h, acpi_pptt_cache describes the fields in the original
Cache Type Structure. In PPTT table version 3 a new field was added at the
end, cache_id. This is described in acpi_pptt_cache_v1 but rather than
including all v1 fields it just includes this one.

In lieu of this being fixed in acpica, introduce acpi_pptt_cache_v1_full to
contain all the fields of the Cache Type Structure . Update the existing
code to use this new struct. This simplifies the code and removes a
non-standard use of ACPI_ADD_PTR.

Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Reviewed-by: Gavin Shan <gshan@redhat.com>
Reviewed-by: Hanjun Guo <guohanjun@huawei.com>
Reviewed-by: Jeremy Linton <jeremy.linton@arm.com>
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Hanjun Guo <guohanjun@huawei.com>
Signed-off-by: Ben Horgan <ben.horgan@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

diff --git a/drivers/acpi/pptt.c b/drivers/acpi/pptt.c
index 2856254e29d73b35fb9d4d5dbf5abe75938d46e2..ef39b176dc00cced88226c853ed166a27fa5c326 100644 (file)
--- a/drivers/acpi/pptt.c
+++ b/drivers/acpi/pptt.c
@@ -21,6 +21,25 @@
 #include <linux/cacheinfo.h>
 #include <acpi/processor.h>
 
+/*
+ * The acpi_pptt_cache_v1 in actbl2.h, which is imported from acpica,
+ * only contains the cache_id field rather than all the fields of the
+ * Cache Type Structure. Use this alternative structure until it is
+ * resolved in acpica.
+ */
+struct acpi_pptt_cache_v1_full {
+       struct acpi_subtable_header header;
+       u16 reserved;
+       u32 flags;
+       u32 next_level_of_cache;
+       u32 size;
+       u32 number_of_sets;
+       u8 associativity;
+       u8 attributes;
+       u16 line_size;
+       u32 cache_id;
+} __packed;
+
 static struct acpi_subtable_header *fetch_pptt_subtable(struct acpi_table_header *table_hdr,
                                                        u32 pptt_ref)
 {
@@ -56,6 +75,18 @@ static struct acpi_pptt_cache *fetch_pptt_cache(struct acpi_table_header *table_
        return (struct acpi_pptt_cache *)fetch_pptt_subtable(table_hdr, pptt_ref);
 }
 
+static struct acpi_pptt_cache_v1_full *upgrade_pptt_cache(struct acpi_pptt_cache *cache)
+{
+       if (cache->header.length < sizeof(struct acpi_pptt_cache_v1_full))
+               return NULL;
+
+       /* No use for v1 if the only additional field is invalid */
+       if (!(cache->flags & ACPI_PPTT_CACHE_ID_VALID))
+               return NULL;
+
+       return (struct acpi_pptt_cache_v1_full *)cache;
+}
+
 static struct acpi_subtable_header *acpi_get_pptt_resource(struct acpi_table_header *table_hdr,
                                                           struct acpi_pptt_processor *node,
                                                           int resource)
@@ -355,7 +386,6 @@ static struct acpi_pptt_cache *acpi_find_cache_node(struct acpi_table_header *ta
  * @this_leaf: Kernel cache info structure being updated
  * @found_cache: The PPTT node describing this cache instance
  * @cpu_node: A unique reference to describe this cache instance
- * @revision: The revision of the PPTT table
  *
  * The ACPI spec implies that the fields in the cache structures are used to
  * extend and correct the information probed from the hardware. Lets only
@@ -365,10 +395,9 @@ static struct acpi_pptt_cache *acpi_find_cache_node(struct acpi_table_header *ta
  */
 static void update_cache_properties(struct cacheinfo *this_leaf,
                                    struct acpi_pptt_cache *found_cache,
-                                   struct acpi_pptt_processor *cpu_node,
-                                   u8 revision)
+                                   struct acpi_pptt_processor *cpu_node)
 {
-       struct acpi_pptt_cache_v1* found_cache_v1;
+       struct acpi_pptt_cache_v1_full *found_cache_v1;
 
        this_leaf->fw_token = cpu_node;
        if (found_cache->flags & ACPI_PPTT_SIZE_PROPERTY_VALID)
@@ -418,9 +447,8 @@ static void update_cache_properties(struct cacheinfo *this_leaf,
            found_cache->flags & ACPI_PPTT_CACHE_TYPE_VALID)
                this_leaf->type = CACHE_TYPE_UNIFIED;
 
-       if (revision >= 3 && (found_cache->flags & ACPI_PPTT_CACHE_ID_VALID)) {
-               found_cache_v1 = ACPI_ADD_PTR(struct acpi_pptt_cache_v1,
-                                             found_cache, sizeof(struct acpi_pptt_cache));
+       found_cache_v1 = upgrade_pptt_cache(found_cache);
+       if (found_cache_v1) {
                this_leaf->id = found_cache_v1->cache_id;
                this_leaf->attributes |= CACHE_ID;
        }
@@ -445,8 +473,7 @@ static void cache_setup_acpi_cpu(struct acpi_table_header *table,
                pr_debug("found = %p %p\n", found_cache, cpu_node);
                if (found_cache)
                        update_cache_properties(this_leaf, found_cache,
-                                               ACPI_TO_POINTER(ACPI_PTR_DIFF(cpu_node, table)),
-                                               table->revision);
+                                               ACPI_TO_POINTER(ACPI_PTR_DIFF(cpu_node, table)));
 
                index++;
        }