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-rw-r--r--drivers/base/regmap/internal.h1
-rw-r--r--drivers/base/regmap/regcache-flat.c102
-rw-r--r--drivers/base/regmap/regcache.c1
-rw-r--r--drivers/base/regmap/regmap-kunit.c22
-rw-r--r--include/linux/regmap.h17
5 files changed, 126 insertions, 17 deletions
diff --git a/drivers/base/regmap/internal.h b/drivers/base/regmap/internal.h
index 6f31240ee4a9..8d19a1414d5b 100644
--- a/drivers/base/regmap/internal.h
+++ b/drivers/base/regmap/internal.h
@@ -288,6 +288,7 @@ enum regmap_endian regmap_get_val_endian(struct device *dev,
const struct regmap_bus *bus,
const struct regmap_config *config);
+extern struct regcache_ops regcache_flat_sparse_ops;
extern struct regcache_ops regcache_rbtree_ops;
extern struct regcache_ops regcache_maple_ops;
extern struct regcache_ops regcache_flat_ops;
diff --git a/drivers/base/regmap/regcache-flat.c b/drivers/base/regmap/regcache-flat.c
index f36d3618b67c..86f7679175b1 100644
--- a/drivers/base/regmap/regcache-flat.c
+++ b/drivers/base/regmap/regcache-flat.c
@@ -6,7 +6,11 @@
//
// Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
+#include <linux/bitmap.h>
+#include <linux/bitops.h>
#include <linux/device.h>
+#include <linux/limits.h>
+#include <linux/overflow.h>
#include <linux/seq_file.h>
#include <linux/slab.h>
@@ -18,34 +22,62 @@ static inline unsigned int regcache_flat_get_index(const struct regmap *map,
return regcache_get_index_by_order(map, reg);
}
+struct regcache_flat_data {
+ unsigned long *valid;
+ unsigned int data[];
+};
+
static int regcache_flat_init(struct regmap *map)
{
int i;
- unsigned int *cache;
+ size_t cache_data_size;
+ unsigned int cache_size;
+ struct regcache_flat_data *cache;
if (!map || map->reg_stride_order < 0 || !map->max_register_is_set)
return -EINVAL;
- map->cache = kcalloc(regcache_flat_get_index(map, map->max_register)
- + 1, sizeof(unsigned int), map->alloc_flags);
- if (!map->cache)
+ cache_size = regcache_flat_get_index(map, map->max_register) + 1;
+ cache_data_size = struct_size(cache, data, cache_size);
+
+ if (cache_data_size == SIZE_MAX) {
+ dev_err(map->dev, "cannot allocate regmap cache");
return -ENOMEM;
+ }
- cache = map->cache;
+ cache = kzalloc(cache_data_size, map->alloc_flags);
+ if (!cache)
+ return -ENOMEM;
+
+ cache->valid = bitmap_zalloc(cache_size, map->alloc_flags);
+ if (!cache->valid)
+ goto err_free;
+
+ map->cache = cache;
for (i = 0; i < map->num_reg_defaults; i++) {
unsigned int reg = map->reg_defaults[i].reg;
unsigned int index = regcache_flat_get_index(map, reg);
- cache[index] = map->reg_defaults[i].def;
+ cache->data[index] = map->reg_defaults[i].def;
+ __set_bit(index, cache->valid);
}
return 0;
+
+err_free:
+ kfree(cache);
+ return -ENOMEM;
}
static int regcache_flat_exit(struct regmap *map)
{
- kfree(map->cache);
+ struct regcache_flat_data *cache = map->cache;
+
+ if (cache)
+ bitmap_free(cache->valid);
+
+ kfree(cache);
map->cache = NULL;
return 0;
@@ -54,10 +86,24 @@ static int regcache_flat_exit(struct regmap *map)
static int regcache_flat_read(struct regmap *map,
unsigned int reg, unsigned int *value)
{
- unsigned int *cache = map->cache;
+ struct regcache_flat_data *cache = map->cache;
unsigned int index = regcache_flat_get_index(map, reg);
- *value = cache[index];
+ *value = cache->data[index];
+
+ return 0;
+}
+
+static int regcache_flat_sparse_read(struct regmap *map,
+ unsigned int reg, unsigned int *value)
+{
+ struct regcache_flat_data *cache = map->cache;
+ unsigned int index = regcache_flat_get_index(map, reg);
+
+ if (unlikely(!test_bit(index, cache->valid)))
+ return -ENOENT;
+
+ *value = cache->data[index];
return 0;
}
@@ -65,10 +111,34 @@ static int regcache_flat_read(struct regmap *map,
static int regcache_flat_write(struct regmap *map, unsigned int reg,
unsigned int value)
{
- unsigned int *cache = map->cache;
+ struct regcache_flat_data *cache = map->cache;
unsigned int index = regcache_flat_get_index(map, reg);
- cache[index] = value;
+ cache->data[index] = value;
+
+ return 0;
+}
+
+static int regcache_flat_sparse_write(struct regmap *map, unsigned int reg,
+ unsigned int value)
+{
+ struct regcache_flat_data *cache = map->cache;
+ unsigned int index = regcache_flat_get_index(map, reg);
+
+ cache->data[index] = value;
+ __set_bit(index, cache->valid);
+
+ return 0;
+}
+
+static int regcache_flat_drop(struct regmap *map, unsigned int min,
+ unsigned int max)
+{
+ struct regcache_flat_data *cache = map->cache;
+ unsigned int bitmap_min = regcache_flat_get_index(map, min);
+ unsigned int bitmap_max = regcache_flat_get_index(map, max);
+
+ bitmap_clear(cache->valid, bitmap_min, bitmap_max + 1 - bitmap_min);
return 0;
}
@@ -81,3 +151,13 @@ struct regcache_ops regcache_flat_ops = {
.read = regcache_flat_read,
.write = regcache_flat_write,
};
+
+struct regcache_ops regcache_flat_sparse_ops = {
+ .type = REGCACHE_FLAT_S,
+ .name = "flat-sparse",
+ .init = regcache_flat_init,
+ .exit = regcache_flat_exit,
+ .read = regcache_flat_sparse_read,
+ .write = regcache_flat_sparse_write,
+ .drop = regcache_flat_drop,
+};
diff --git a/drivers/base/regmap/regcache.c b/drivers/base/regmap/regcache.c
index c7650fa434ad..0392f5525cf3 100644
--- a/drivers/base/regmap/regcache.c
+++ b/drivers/base/regmap/regcache.c
@@ -16,6 +16,7 @@
#include "internal.h"
static const struct regcache_ops *cache_types[] = {
+ &regcache_flat_sparse_ops,
&regcache_rbtree_ops,
&regcache_maple_ops,
&regcache_flat_ops,
diff --git a/drivers/base/regmap/regmap-kunit.c b/drivers/base/regmap/regmap-kunit.c
index 95c5bf2a78ee..f6fc5ed016da 100644
--- a/drivers/base/regmap/regmap-kunit.c
+++ b/drivers/base/regmap/regmap-kunit.c
@@ -54,6 +54,8 @@ static const char *regcache_type_name(enum regcache_type type)
return "none";
case REGCACHE_FLAT:
return "flat";
+ case REGCACHE_FLAT_S:
+ return "flat-sparse";
case REGCACHE_RBTREE:
return "rbtree";
case REGCACHE_MAPLE:
@@ -93,6 +95,8 @@ static const struct regmap_test_param regcache_types_list[] = {
{ .cache = REGCACHE_NONE, .fast_io = true },
{ .cache = REGCACHE_FLAT },
{ .cache = REGCACHE_FLAT, .fast_io = true },
+ { .cache = REGCACHE_FLAT_S },
+ { .cache = REGCACHE_FLAT_S, .fast_io = true },
{ .cache = REGCACHE_RBTREE },
{ .cache = REGCACHE_RBTREE, .fast_io = true },
{ .cache = REGCACHE_MAPLE },
@@ -104,6 +108,8 @@ KUNIT_ARRAY_PARAM(regcache_types, regcache_types_list, param_to_desc);
static const struct regmap_test_param real_cache_types_only_list[] = {
{ .cache = REGCACHE_FLAT },
{ .cache = REGCACHE_FLAT, .fast_io = true },
+ { .cache = REGCACHE_FLAT_S },
+ { .cache = REGCACHE_FLAT_S, .fast_io = true },
{ .cache = REGCACHE_RBTREE },
{ .cache = REGCACHE_RBTREE, .fast_io = true },
{ .cache = REGCACHE_MAPLE },
@@ -119,6 +125,12 @@ static const struct regmap_test_param real_cache_types_list[] = {
{ .cache = REGCACHE_FLAT, .from_reg = 0x2002 },
{ .cache = REGCACHE_FLAT, .from_reg = 0x2003 },
{ .cache = REGCACHE_FLAT, .from_reg = 0x2004 },
+ { .cache = REGCACHE_FLAT_S, .from_reg = 0 },
+ { .cache = REGCACHE_FLAT_S, .from_reg = 0, .fast_io = true },
+ { .cache = REGCACHE_FLAT_S, .from_reg = 0x2001 },
+ { .cache = REGCACHE_FLAT_S, .from_reg = 0x2002 },
+ { .cache = REGCACHE_FLAT_S, .from_reg = 0x2003 },
+ { .cache = REGCACHE_FLAT_S, .from_reg = 0x2004 },
{ .cache = REGCACHE_RBTREE, .from_reg = 0 },
{ .cache = REGCACHE_RBTREE, .from_reg = 0, .fast_io = true },
{ .cache = REGCACHE_RBTREE, .from_reg = 0x2001 },
@@ -136,6 +148,12 @@ static const struct regmap_test_param real_cache_types_list[] = {
KUNIT_ARRAY_PARAM(real_cache_types, real_cache_types_list, param_to_desc);
static const struct regmap_test_param sparse_cache_types_list[] = {
+ { .cache = REGCACHE_FLAT_S, .from_reg = 0 },
+ { .cache = REGCACHE_FLAT_S, .from_reg = 0, .fast_io = true },
+ { .cache = REGCACHE_FLAT_S, .from_reg = 0x2001 },
+ { .cache = REGCACHE_FLAT_S, .from_reg = 0x2002 },
+ { .cache = REGCACHE_FLAT_S, .from_reg = 0x2003 },
+ { .cache = REGCACHE_FLAT_S, .from_reg = 0x2004 },
{ .cache = REGCACHE_RBTREE, .from_reg = 0 },
{ .cache = REGCACHE_RBTREE, .from_reg = 0, .fast_io = true },
{ .cache = REGCACHE_RBTREE, .from_reg = 0x2001 },
@@ -1597,6 +1615,8 @@ static const struct regmap_test_param raw_types_list[] = {
{ .cache = REGCACHE_NONE, .val_endian = REGMAP_ENDIAN_BIG },
{ .cache = REGCACHE_FLAT, .val_endian = REGMAP_ENDIAN_LITTLE },
{ .cache = REGCACHE_FLAT, .val_endian = REGMAP_ENDIAN_BIG },
+ { .cache = REGCACHE_FLAT_S, .val_endian = REGMAP_ENDIAN_LITTLE },
+ { .cache = REGCACHE_FLAT_S, .val_endian = REGMAP_ENDIAN_BIG },
{ .cache = REGCACHE_RBTREE, .val_endian = REGMAP_ENDIAN_LITTLE },
{ .cache = REGCACHE_RBTREE, .val_endian = REGMAP_ENDIAN_BIG },
{ .cache = REGCACHE_MAPLE, .val_endian = REGMAP_ENDIAN_LITTLE },
@@ -1608,6 +1628,8 @@ KUNIT_ARRAY_PARAM(raw_test_types, raw_types_list, param_to_desc);
static const struct regmap_test_param raw_cache_types_list[] = {
{ .cache = REGCACHE_FLAT, .val_endian = REGMAP_ENDIAN_LITTLE },
{ .cache = REGCACHE_FLAT, .val_endian = REGMAP_ENDIAN_BIG },
+ { .cache = REGCACHE_FLAT_S, .val_endian = REGMAP_ENDIAN_LITTLE },
+ { .cache = REGCACHE_FLAT_S, .val_endian = REGMAP_ENDIAN_BIG },
{ .cache = REGCACHE_RBTREE, .val_endian = REGMAP_ENDIAN_LITTLE },
{ .cache = REGCACHE_RBTREE, .val_endian = REGMAP_ENDIAN_BIG },
{ .cache = REGCACHE_MAPLE, .val_endian = REGMAP_ENDIAN_LITTLE },
diff --git a/include/linux/regmap.h b/include/linux/regmap.h
index 4e1ac1fbcec4..17bed25dc4e3 100644
--- a/include/linux/regmap.h
+++ b/include/linux/regmap.h
@@ -55,18 +55,23 @@ struct sdw_slave;
#define REGMAP_DOWNSHIFT(s) (s)
/*
- * The supported cache types, the default is no cache. Any new caches
- * should usually use the maple tree cache unless they specifically
- * require that there are never any allocations at runtime and can't
- * provide defaults in which case they should use the flat cache. The
- * rbtree cache *may* have some performance advantage for very low end
- * systems that make heavy use of cache syncs but is mainly legacy.
+ * The supported cache types, the default is no cache. Any new caches should
+ * usually use the maple tree cache unless they specifically require that there
+ * are never any allocations at runtime in which case they should use the sparse
+ * flat cache. The rbtree cache *may* have some performance advantage for very
+ * low end systems that make heavy use of cache syncs but is mainly legacy.
+ * These caches are sparse and entries will be initialized from hardware if no
+ * default has been provided.
+ * The non-sparse flat cache is provided for compatibility with existing users
+ * and will zero-initialize cache entries for which no defaults are provided.
+ * New users should use the sparse flat cache.
*/
enum regcache_type {
REGCACHE_NONE,
REGCACHE_RBTREE,
REGCACHE_FLAT,
REGCACHE_MAPLE,
+ REGCACHE_FLAT_S,
};
/**