From 75a5f89f635c2b7cd1f94fcaef5f764d480c8481 Mon Sep 17 00:00:00 2001 From: Mark Brown Date: Fri, 29 Mar 2013 20:50:07 +0000 Subject: regmap: cache: Write consecutive registers in a single block write When syncing blocks of data using raw writes combine the writes into a single block write, saving us bus overhead for setup, addressing and teardown. Currently the block write is done unconditionally as it is expected that hardware which has a register format which can support raw writes will support auto incrementing writes, this decision may need to be revised in future. Signed-off-by: Mark Brown Reviewed-by: Dimitris Papastamos --- drivers/base/regmap/regcache.c | 64 +++++++++++++++++++++++++++++++----------- 1 file changed, 47 insertions(+), 17 deletions(-) (limited to 'drivers/base/regmap') diff --git a/drivers/base/regmap/regcache.c b/drivers/base/regmap/regcache.c index da4d984..d81f605 100644 --- a/drivers/base/regmap/regcache.c +++ b/drivers/base/regmap/regcache.c @@ -579,42 +579,72 @@ static int regcache_sync_block_single(struct regmap *map, void *block, return 0; } +static int regcache_sync_block_raw_flush(struct regmap *map, const void **data, + unsigned int base, unsigned int cur) +{ + size_t val_bytes = map->format.val_bytes; + int ret, count; + + if (*data == NULL) + return 0; + + count = cur - base; + + dev_dbg(map->dev, "Writing %d bytes for %d registers from 0x%x-0x%x\n", + count * val_bytes, count, base, cur - 1); + + map->cache_bypass = 1; + + ret = _regmap_raw_write(map, base, *data, count * val_bytes, + false); + + map->cache_bypass = 0; + + *data = NULL; + + return ret; +} + int regcache_sync_block_raw(struct regmap *map, void *block, unsigned int block_base, unsigned int start, unsigned int end) { - unsigned int i, regtmp, val; - const void *addr; + unsigned int i, val; + unsigned int regtmp = 0; + unsigned int base = 0; + const void *data = NULL; int ret; for (i = start; i < end; i++) { regtmp = block_base + (i * map->reg_stride); - if (!regcache_reg_present(map, regtmp)) + if (!regcache_reg_present(map, regtmp)) { + ret = regcache_sync_block_raw_flush(map, &data, + base, regtmp); + if (ret != 0) + return ret; continue; + } val = regcache_get_val(map, block, i); /* Is this the hardware default? If so skip. */ ret = regcache_lookup_reg(map, regtmp); - if (ret >= 0 && val == map->reg_defaults[ret].def) + if (ret >= 0 && val == map->reg_defaults[ret].def) { + ret = regcache_sync_block_raw_flush(map, &data, + base, regtmp); + if (ret != 0) + return ret; continue; + } - map->cache_bypass = 1; - - addr = regcache_get_val_addr(map, block, i); - ret = _regmap_raw_write(map, regtmp, addr, - map->format.val_bytes, - false); - - map->cache_bypass = 0; - if (ret != 0) - return ret; - dev_dbg(map->dev, "Synced register %#x, value %#x\n", - regtmp, val); + if (!data) { + data = regcache_get_val_addr(map, block, i); + base = regtmp; + } } - return 0; + return regcache_sync_block_raw_flush(map, &data, base, regtmp); } int regcache_sync_block(struct regmap *map, void *block, -- cgit v1.1