[PATCH 1/4] regmap: Add support for discarding parts of the register cache

[PATCH 1/4] regmap: Add support for discarding parts of the register cache

[Mark Brown]

Allow drivers to discard parts of the register cache, for example if part
of the hardware has been reset.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
---
 drivers/base/regmap/internal.h |    1 +
 drivers/base/regmap/regcache.c |   37 +++++++++++++++++++++++++++++++++++++
 include/linux/regmap.h         |    9 +++++++++
 include/trace/events/regmap.h  |   23 +++++++++++++++++++++++
 4 files changed, 70 insertions(+)

diff --git a/drivers/base/regmap/internal.h b/drivers/base/regmap/internal.h
index c130536..b33a4ff 100644
--- a/drivers/base/regmap/internal.h
+++ b/drivers/base/regmap/internal.h
@@ -148,6 +148,7 @@ struct regcache_ops {
 	int (*read)(struct regmap *map, unsigned int reg, unsigned int *value);
 	int (*write)(struct regmap *map, unsigned int reg, unsigned int value);
 	int (*sync)(struct regmap *map, unsigned int min, unsigned int max);
+	int (*drop)(struct regmap *map, unsigned int min, unsigned int max);
 };
 
 bool regmap_writeable(struct regmap *map, unsigned int reg);
diff --git a/drivers/base/regmap/regcache.c b/drivers/base/regmap/regcache.c
index 1196c21..14c6eef 100644
--- a/drivers/base/regmap/regcache.c
+++ b/drivers/base/regmap/regcache.c
@@ -359,6 +359,43 @@ out:
 EXPORT_SYMBOL_GPL(regcache_sync_region);
 
 /**
+ * regcache_drop_region: Discard part of the register cache
+ *
+ * @map: map to operate on
+ * @min: first register to discard
+ * @max: last register to discard
+ *
+ * Discard part of the register cache.
+ *
+ * Return a negative value on failure, 0 on success.
+ */
+int regcache_drop_region(struct regmap *map, unsigned int min,
+			 unsigned int max)
+{
+	unsigned int reg;
+	int ret = 0;
+
+	if (!map->cache_present && !(map->cache_ops && map->cache_ops->drop))
+		return -EINVAL;
+
+	map->lock(map);
+
+	trace_regcache_drop_region(map->dev, min, max);
+
+	if (map->cache_present)
+		for (reg = min; reg < max + 1; reg++)
+			clear_bit(reg, map->cache_present);
+
+	if (map->cache_ops && map->cache_ops->drop)
+		ret = map->cache_ops->drop(map, min, max);
+
+	map->unlock(map);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(regcache_drop_region);
+
+/**
  * regcache_cache_only: Put a register map into cache only mode
  *
  * @map: map to configure
diff --git a/include/linux/regmap.h b/include/linux/regmap.h
index 02d84e2..5067ee9 100644
--- a/include/linux/regmap.h
+++ b/include/linux/regmap.h
@@ -394,6 +394,8 @@ bool regmap_can_raw_write(struct regmap *map);
 int regcache_sync(struct regmap *map);
 int regcache_sync_region(struct regmap *map, unsigned int min,
 			 unsigned int max);
+int regcache_drop_region(struct regmap *map, unsigned int min,
+			 unsigned int max);
 void regcache_cache_only(struct regmap *map, bool enable);
 void regcache_cache_bypass(struct regmap *map, bool enable);
 void regcache_mark_dirty(struct regmap *map);
@@ -562,6 +564,13 @@ static inline int regcache_sync_region(struct regmap *map, unsigned int min,
 	return -EINVAL;
 }
 
+static inline int regcache_drop_region(struct regmap *map, unsigned int min,
+				       unsigned int max)
+{
+	WARN_ONCE(1, "regmap API is disabled");
+	return -EINVAL;
+}
+
 static inline void regcache_cache_only(struct regmap *map, bool enable)
 {
 	WARN_ONCE(1, "regmap API is disabled");
diff --git a/include/trace/events/regmap.h b/include/trace/events/regmap.h
index a43a2f6..23d5615 100644
--- a/include/trace/events/regmap.h
+++ b/include/trace/events/regmap.h
@@ -223,6 +223,29 @@ DEFINE_EVENT(regmap_async, regmap_async_complete_done,
 
 );
 
+TRACE_EVENT(regcache_drop_region,
+
+	TP_PROTO(struct device *dev, unsigned int from,
+		 unsigned int to),
+
+	TP_ARGS(dev, from, to),
+
+	TP_STRUCT__entry(
+		__string(       name,           dev_name(dev)   )
+		__field(	unsigned int,	from		)
+		__field(	unsigned int,	to		)
+	),
+
+	TP_fast_assign(
+		__assign_str(name, dev_name(dev));
+		__entry->from = from;
+		__entry->to = to;
+	),
+
+	TP_printk("%s %u-%u", __get_str(name), (unsigned int)__entry->from,
+		  (unsigned int)__entry->to)
+);
+
 #endif /* _TRACE_REGMAP_H */
 
 /* This part must be outside protection */
-- 
1.7.10.4

[PATCH 2/4] regmap: Make regmap_check_range_table() a public API

[Mark Brown]

Allow drivers to use an access table as part of their implementation.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
---
 drivers/base/regmap/regmap.c |   14 +++++++-------
 include/linux/regmap.h       |    3 +++
 2 files changed, 10 insertions(+), 7 deletions(-)

diff --git a/drivers/base/regmap/regmap.c b/drivers/base/regmap/regmap.c
index a941dcf..307f5a1 100644
--- a/drivers/base/regmap/regmap.c
+++ b/drivers/base/regmap/regmap.c
@@ -65,9 +65,8 @@ bool regmap_reg_in_ranges(unsigned int reg,
 }
 EXPORT_SYMBOL_GPL(regmap_reg_in_ranges);
 
-static bool _regmap_check_range_table(struct regmap *map,
-				      unsigned int reg,
-				      const struct regmap_access_table *table)
+bool regmap_check_range_table(struct regmap *map, unsigned int reg,
+			      const struct regmap_access_table *table)
 {
 	/* Check "no ranges" first */
 	if (regmap_reg_in_ranges(reg, table->no_ranges, table->n_no_ranges))
@@ -80,6 +79,7 @@ static bool _regmap_check_range_table(struct regmap *map,
 	return regmap_reg_in_ranges(reg, table->yes_ranges,
 				    table->n_yes_ranges);
 }
+EXPORT_SYMBOL_GPL(regmap_check_range_table);
 
 bool regmap_writeable(struct regmap *map, unsigned int reg)
 {
@@ -90,7 +90,7 @@ bool regmap_writeable(struct regmap *map, unsigned int reg)
 		return map->writeable_reg(map->dev, reg);
 
 	if (map->wr_table)
-		return _regmap_check_range_table(map, reg, map->wr_table);
+		return regmap_check_range_table(map, reg, map->wr_table);
 
 	return true;
 }
@@ -107,7 +107,7 @@ bool regmap_readable(struct regmap *map, unsigned int reg)
 		return map->readable_reg(map->dev, reg);
 
 	if (map->rd_table)
-		return _regmap_check_range_table(map, reg, map->rd_table);
+		return regmap_check_range_table(map, reg, map->rd_table);
 
 	return true;
 }
@@ -121,7 +121,7 @@ bool regmap_volatile(struct regmap *map, unsigned int reg)
 		return map->volatile_reg(map->dev, reg);
 
 	if (map->volatile_table)
-		return _regmap_check_range_table(map, reg, map->volatile_table);
+		return regmap_check_range_table(map, reg, map->volatile_table);
 
 	return true;
 }
@@ -135,7 +135,7 @@ bool regmap_precious(struct regmap *map, unsigned int reg)
 		return map->precious_reg(map->dev, reg);
 
 	if (map->precious_table)
-		return _regmap_check_range_table(map, reg, map->precious_table);
+		return regmap_check_range_table(map, reg, map->precious_table);
 
 	return false;
 }
diff --git a/include/linux/regmap.h b/include/linux/regmap.h
index 5067ee9..d6f3221 100644
--- a/include/linux/regmap.h
+++ b/include/linux/regmap.h
@@ -400,6 +400,9 @@ void regcache_cache_only(struct regmap *map, bool enable);
 void regcache_cache_bypass(struct regmap *map, bool enable);
 void regcache_mark_dirty(struct regmap *map);
 
+bool regmap_check_range_table(struct regmap *map, unsigned int reg,
+			      const struct regmap_access_table *table);
+
 int regmap_register_patch(struct regmap *map, const struct reg_default *regs,
 			  int num_regs);
 
-- 
1.7.10.4

[PATCH 3/4] regmap: rbtree: Factor out node allocation

[Mark Brown]

In preparation for being slightly smarter about how we allocate memory
factor out the node allocation.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
---
 drivers/base/regmap/regcache-rbtree.c |   41 ++++++++++++++++++++++-----------
 1 file changed, 27 insertions(+), 14 deletions(-)

diff --git a/drivers/base/regmap/regcache-rbtree.c b/drivers/base/regmap/regcache-rbtree.c
index e9316b3..47f8047 100644
--- a/drivers/base/regmap/regcache-rbtree.c
+++ b/drivers/base/regmap/regcache-rbtree.c
@@ -304,6 +304,27 @@ static int regcache_rbtree_insert_to_block(struct regmap *map,
 	return 0;
 }
 
+static struct regcache_rbtree_node *
+regcache_rbtree_node_alloc(struct regmap *map, unsigned int reg)
+{
+	struct regcache_rbtree_node *rbnode;
+
+	rbnode = kzalloc(sizeof(*rbnode), GFP_KERNEL);
+	if (!rbnode)
+		return NULL;
+
+	rbnode->blklen = sizeof(*rbnode);
+	rbnode->base_reg = reg;
+	rbnode->block = kmalloc(rbnode->blklen * map->cache_word_size,
+				GFP_KERNEL);
+	if (!rbnode->block) {
+		kfree(rbnode);
+		return NULL;
+	}
+
+	return rbnode;
+}
+
 static int regcache_rbtree_write(struct regmap *map, unsigned int reg,
 				 unsigned int value)
 {
@@ -354,23 +375,15 @@ static int regcache_rbtree_write(struct regmap *map, unsigned int reg,
 				return 0;
 			}
 		}
-		/* we did not manage to find a place to insert it in an existing
-		 * block so create a new rbnode with a single register in its block.
-		 * This block will get populated further if any other adjacent
-		 * registers get modified in the future.
+
+		/* We did not manage to find a place to insert it in
+		 * an existing block so create a new rbnode.
 		 */
-		rbnode = kzalloc(sizeof *rbnode, GFP_KERNEL);
+		rbnode = regcache_rbtree_node_alloc(map, reg);
 		if (!rbnode)
 			return -ENOMEM;
-		rbnode->blklen = sizeof(*rbnode);
-		rbnode->base_reg = reg;
-		rbnode->block = kmalloc(rbnode->blklen * map->cache_word_size,
-					GFP_KERNEL);
-		if (!rbnode->block) {
-			kfree(rbnode);
-			return -ENOMEM;
-		}
-		regcache_rbtree_set_register(map, rbnode, 0, value);
+		regcache_rbtree_set_register(map, rbnode,
+					     reg - rbnode->base_reg, value);
 		regcache_rbtree_insert(map, &rbtree_ctx->root, rbnode);
 		rbtree_ctx->cached_rbnode = rbnode;
 	}
-- 
1.7.10.4

[PATCH 4/4] regmap: rbtree: Use range information to allocate nodes

[Mark Brown]

If range information has been provided then when we allocate a rbnode
within a range allocate the entire range. The goal is to minimise the
number of reallocations done when combining or extending blocks. At
present only readability and yes_ranges are taken into account, this is
expected to cover most cases efficiently.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
---
 drivers/base/regmap/regcache-rbtree.c |   25 +++++++++++++++++++++++--
 1 file changed, 23 insertions(+), 2 deletions(-)

diff --git a/drivers/base/regmap/regcache-rbtree.c b/drivers/base/regmap/regcache-rbtree.c
index 47f8047..24b06a4 100644
--- a/drivers/base/regmap/regcache-rbtree.c
+++ b/drivers/base/regmap/regcache-rbtree.c
@@ -308,13 +308,34 @@ static struct regcache_rbtree_node *
 regcache_rbtree_node_alloc(struct regmap *map, unsigned int reg)
 {
 	struct regcache_rbtree_node *rbnode;
+	const struct regmap_range *range;
+	int i;
 
 	rbnode = kzalloc(sizeof(*rbnode), GFP_KERNEL);
 	if (!rbnode)
 		return NULL;
 
-	rbnode->blklen = sizeof(*rbnode);
-	rbnode->base_reg = reg;
+	/* If there is a read table then use it to guess at an allocation */
+	if (map->rd_table) {
+		for (i = 0; i < map->rd_table->n_yes_ranges; i++) {
+			if (regmap_reg_in_range(reg,
+						&map->rd_table->yes_ranges[i]))
+				break;
+		}
+
+		if (i != map->rd_table->n_yes_ranges) {
+			range = &map->rd_table->yes_ranges[i];
+			rbnode->blklen = range->range_max - range->range_min
+				+ 1;
+			rbnode->base_reg = range->range_min;
+		}
+	}
+
+	if (!rbnode->blklen) {
+		rbnode->blklen = sizeof(*rbnode);
+		rbnode->base_reg = reg;
+	}
+
 	rbnode->block = kmalloc(rbnode->blklen * map->cache_word_size,
 				GFP_KERNEL);
 	if (!rbnode->block) {
-- 
1.7.10.4