| Message ID | 1443681187-29505-1-git-send-email-jon@ringle.org |
|---|---|
| State | Superseded, archived |
| Delegated to: | David Miller |
| Headers | show |
On Thu, Oct 01, 2015 at 02:33:06AM -0400, jon@ringle.org wrote: > @@ -2509,6 +2510,10 @@ static int _regmap_update_bits(struct regmap *map, unsigned int reg, > int ret; > unsigned int tmp, orig; > > + if (map->reg_update_bits) > + return map->reg_update_bits(map->bus_context, reg, mask, val, > + change, force_write); > + > ret = _regmap_read(map, reg, &orig); > if (ret != 0) > return ret; This completely bypasses and therefore breaks the cache infrastructure.
On Thu, 1 Oct 2015, Mark Brown wrote: > On Thu, Oct 01, 2015 at 02:33:06AM -0400, jon@ringle.org wrote: > > > @@ -2509,6 +2510,10 @@ static int _regmap_update_bits(struct regmap *map, unsigned int reg, > > int ret; > > unsigned int tmp, orig; > > > > + if (map->reg_update_bits) > > + return map->reg_update_bits(map->bus_context, reg, mask, val, > > + change, force_write); > > + > > ret = _regmap_read(map, reg, &orig); > > if (ret != 0) > > return ret; > > This completely bypasses and therefore breaks the cache infrastructure. > Hi Mark, Right after sending the v2 patch, I realized that calling the custom reg_update_bits would only be applicable for registers that are marked as volatile. Would the following solution be acceptable (it would also simplify the regmap_update_bits in the encx24j600 driver): if (regmap_volatile(map, reg) && map->reg_update_bits) { return map->reg_update_bits(map->bus_context, reg, mask, val, change, force_write); The cache state should not matter for volatile registers, right? -Jon -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Thu, Oct 01, 2015 at 08:29:19AM -0400, Jon Ringle wrote: > On Thu, 1 Oct 2015, Mark Brown wrote: > > This completely bypasses and therefore breaks the cache infrastructure. > Right after sending the v2 patch, I realized that calling the > custom reg_update_bits would only be applicable for registers that are > marked as volatile. Would the following solution be acceptable (it would Well, it should still *work* with a cache, though it's certainly true that it's unlikely to have any performance benefit with cached register since the read part of the read/modify/write cycle is essentially free with the cache. > also simplify the regmap_update_bits in the encx24j600 driver): > if (regmap_volatile(map, reg) && map->reg_update_bits) { > return map->reg_update_bits(map->bus_context, reg, mask, > val, change, force_write); > The cache state should not matter for volatile registers, right? Right. I see you've sent a new patch already, I'll reply to that after I've thought about it a little.
diff --git a/drivers/base/regmap/internal.h b/drivers/base/regmap/internal.h index cc55788..4036d7a 100644 --- a/drivers/base/regmap/internal.h +++ b/drivers/base/regmap/internal.h @@ -98,6 +98,9 @@ struct regmap { int (*reg_read)(void *context, unsigned int reg, unsigned int *val); int (*reg_write)(void *context, unsigned int reg, unsigned int val); + int (*reg_update_bits)(void *context, unsigned int reg, + unsigned int mask, unsigned int val, + bool *change, bool force_write); bool defer_caching; diff --git a/drivers/base/regmap/regmap.c b/drivers/base/regmap/regmap.c index afaf562..ba00d62 100644 --- a/drivers/base/regmap/regmap.c +++ b/drivers/base/regmap/regmap.c @@ -619,6 +619,7 @@ struct regmap *__regmap_init(struct device *dev, goto skip_format_initialization; } else { map->reg_read = _regmap_bus_read; + map->reg_update_bits = bus->reg_update_bits; } reg_endian = regmap_get_reg_endian(bus, config); @@ -2509,6 +2510,10 @@ static int _regmap_update_bits(struct regmap *map, unsigned int reg, int ret; unsigned int tmp, orig; + if (map->reg_update_bits) + return map->reg_update_bits(map->bus_context, reg, mask, val, + change, force_write); + ret = _regmap_read(map, reg, &orig); if (ret != 0) return ret; diff --git a/include/linux/regmap.h b/include/linux/regmap.h index 8fc0bfd..4d3a3b1 100644 --- a/include/linux/regmap.h +++ b/include/linux/regmap.h @@ -296,6 +296,9 @@ typedef int (*regmap_hw_reg_read)(void *context, unsigned int reg, unsigned int *val); typedef int (*regmap_hw_reg_write)(void *context, unsigned int reg, unsigned int val); +typedef int (*regmap_hw_reg_update_bits)(void *context, unsigned int reg, + unsigned int mask, unsigned int val, + bool *change, bool force_write); typedef struct regmap_async *(*regmap_hw_async_alloc)(void); typedef void (*regmap_hw_free_context)(void *context); @@ -335,6 +338,7 @@ struct regmap_bus { regmap_hw_gather_write gather_write; regmap_hw_async_write async_write; regmap_hw_reg_write reg_write; + regmap_hw_reg_update_bits reg_update_bits; regmap_hw_read read; regmap_hw_reg_read reg_read; regmap_hw_free_context free_context;