From a06c488da0b0c1eebf710017675f00b9d5f9cf42 Mon Sep 17 00:00:00 2001 From: Mark Brown Date: Tue, 26 Jan 2016 17:59:30 +0000 Subject: regmap: Add explict native endian flag to DT bindings Currently the binding document says that if no endianness is configured we use native endian but this is not in fact true for all binding types and we do have some devices that really want native endianness such as Broadcom MIPS SoCs where switching the endianness of the CPU also switches the endianness of external IPs. Provide an explicit option for this. Signed-off-by: Mark Brown --- drivers/base/regmap/regmap.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'drivers/base') diff --git a/drivers/base/regmap/regmap.c b/drivers/base/regmap/regmap.c index ee54e841de4a..343263449aff 100644 --- a/drivers/base/regmap/regmap.c +++ b/drivers/base/regmap/regmap.c @@ -557,6 +557,8 @@ enum regmap_endian regmap_get_val_endian(struct device *dev, endian = REGMAP_ENDIAN_BIG; else if (of_property_read_bool(np, "little-endian")) endian = REGMAP_ENDIAN_LITTLE; + else if (of_property_read_bool(np, "native-endian")) + endian = REGMAP_ENDIAN_NATIVE; /* If the endianness was specified in DT, use that */ if (endian != REGMAP_ENDIAN_DEFAULT) -- cgit v1.2.3 From 922a9f936e40001f9b921379aab90047d5990923 Mon Sep 17 00:00:00 2001 From: Mark Brown Date: Wed, 27 Jan 2016 04:50:07 +0000 Subject: regmap: mmio: Convert to regmap_bus and fix accessor usage Currently regmap-mmio uses the __raw accessors to read and write from memory. This is not safe as these interact poorly with spinlocks and are not guaranteed to generate emulated instructions on at least ARM where regmap is commonly used. The APIs that are provided all provide some byte swapping so this is difficult to do with the current regmap-mmio implementation which attempts to use the regmap core byte swapping. We can fix this by modernising the MMIO implementation to use reg_read() and reg_write() operations which were added after the API was implemented and pass simple unsigned integers through to the bus, making use of the formatting provided by the I/O accessors using a similar pattern to that used by the core. This will be less efficient for block I/O operations since we now enable and disable any required clocks per register but it is not clear that any users of regmap-mmio actually use block I/O and there is room to optimise later. This removes support for big endian I/O on 64 bit registers since no I/O accessors are provided, no current users were found and support can be added easily once they are available. In addition make the default endianness little endian. This was the behaviour prior to 29bb45f25ff305 (regmap-mmio: Use native endianness for read/write) and is the behaviour desired by most existing users, the users have been audited and those that need native endianness converted to request it explicitly. Previously native was documented as the default but due to the byte swapping in the accessors this was not correctly implemented. Fixes: 29bb45f25ff305 (regmap-mmio: Use native endianness for read/write) Reported-by: Johannes Berg Tested-by: Johannes Berg Signed-off-by: Mark Brown --- drivers/base/regmap/regmap-mmio.c | 259 ++++++++++++++++++++------------------ 1 file changed, 139 insertions(+), 120 deletions(-) (limited to 'drivers/base') diff --git a/drivers/base/regmap/regmap-mmio.c b/drivers/base/regmap/regmap-mmio.c index 8812bfb9e3b8..7526906ca080 100644 --- a/drivers/base/regmap/regmap-mmio.c +++ b/drivers/base/regmap/regmap-mmio.c @@ -25,26 +25,14 @@ struct regmap_mmio_context { void __iomem *regs; - unsigned reg_bytes; unsigned val_bytes; - unsigned pad_bytes; struct clk *clk; -}; -static inline void regmap_mmio_regsize_check(size_t reg_size) -{ - switch (reg_size) { - case 1: - case 2: - case 4: -#ifdef CONFIG_64BIT - case 8: -#endif - break; - default: - BUG(); - } -} + void (*reg_write)(struct regmap_mmio_context *ctx, + unsigned int reg, unsigned int val); + unsigned int (*reg_read)(struct regmap_mmio_context *ctx, + unsigned int reg); +}; static int regmap_mmio_regbits_check(size_t reg_bits) { @@ -88,72 +76,62 @@ static int regmap_mmio_get_min_stride(size_t val_bits) return min_stride; } -static inline void regmap_mmio_count_check(size_t count, u32 offset) +static void regmap_mmio_write8(struct regmap_mmio_context *ctx, + unsigned int reg, + unsigned int val) +{ + writeb(val, ctx->regs + reg); +} + +static void regmap_mmio_write16le(struct regmap_mmio_context *ctx, + unsigned int reg, + unsigned int val) { - BUG_ON(count <= offset); + writew(val, ctx->regs + reg); } -static inline unsigned int -regmap_mmio_get_offset(const void *reg, size_t reg_size) +static void regmap_mmio_write16be(struct regmap_mmio_context *ctx, + unsigned int reg, + unsigned int val) { - switch (reg_size) { - case 1: - return *(u8 *)reg; - case 2: - return *(u16 *)reg; - case 4: - return *(u32 *)reg; + iowrite16be(val, ctx->regs + reg); +} + +static void regmap_mmio_write32le(struct regmap_mmio_context *ctx, + unsigned int reg, + unsigned int val) +{ + writel(val, ctx->regs + reg); +} + +static void regmap_mmio_write32be(struct regmap_mmio_context *ctx, + unsigned int reg, + unsigned int val) +{ + iowrite32be(val, ctx->regs + reg); +} + #ifdef CONFIG_64BIT - case 8: - return *(u64 *)reg; -#endif - default: - BUG(); - } +static void regmap_mmio_write64le(struct regmap_mmio_context *ctx, + unsigned int reg, + unsigned int val) +{ + writeq(val, ctx->regs + reg); } +#endif -static int regmap_mmio_gather_write(void *context, - const void *reg, size_t reg_size, - const void *val, size_t val_size) +static int regmap_mmio_write(void *context, unsigned int reg, unsigned int val) { struct regmap_mmio_context *ctx = context; - unsigned int offset; int ret; - regmap_mmio_regsize_check(reg_size); - if (!IS_ERR(ctx->clk)) { ret = clk_enable(ctx->clk); if (ret < 0) return ret; } - offset = regmap_mmio_get_offset(reg, reg_size); - - while (val_size) { - switch (ctx->val_bytes) { - case 1: - __raw_writeb(*(u8 *)val, ctx->regs + offset); - break; - case 2: - __raw_writew(*(u16 *)val, ctx->regs + offset); - break; - case 4: - __raw_writel(*(u32 *)val, ctx->regs + offset); - break; -#ifdef CONFIG_64BIT - case 8: - __raw_writeq(*(u64 *)val, ctx->regs + offset); - break; -#endif - default: - /* Should be caught by regmap_mmio_check_config */ - BUG(); - } - val_size -= ctx->val_bytes; - val += ctx->val_bytes; - offset += ctx->val_bytes; - } + ctx->reg_write(ctx, reg, val); if (!IS_ERR(ctx->clk)) clk_disable(ctx->clk); @@ -161,59 +139,56 @@ static int regmap_mmio_gather_write(void *context, return 0; } -static int regmap_mmio_write(void *context, const void *data, size_t count) +static unsigned int regmap_mmio_read8(struct regmap_mmio_context *ctx, + unsigned int reg) { - struct regmap_mmio_context *ctx = context; - unsigned int offset = ctx->reg_bytes + ctx->pad_bytes; + return readb(ctx->regs + reg); +} + +static unsigned int regmap_mmio_read16le(struct regmap_mmio_context *ctx, + unsigned int reg) +{ + return readw(ctx->regs + reg); +} + +static unsigned int regmap_mmio_read16be(struct regmap_mmio_context *ctx, + unsigned int reg) +{ + return ioread16be(ctx->regs + reg); +} + +static unsigned int regmap_mmio_read32le(struct regmap_mmio_context *ctx, + unsigned int reg) +{ + return readl(ctx->regs + reg); +} - regmap_mmio_count_check(count, offset); +static unsigned int regmap_mmio_read32be(struct regmap_mmio_context *ctx, + unsigned int reg) +{ + return ioread32be(ctx->regs + reg); +} - return regmap_mmio_gather_write(context, data, ctx->reg_bytes, - data + offset, count - offset); +#ifdef CONFIG_64BIT +static unsigned int regmap_mmio_read64le(struct regmap_mmio_context *ctx, + unsigned int reg) +{ + return readq(ctx->regs + reg); } +#endif -static int regmap_mmio_read(void *context, - const void *reg, size_t reg_size, - void *val, size_t val_size) +static int regmap_mmio_read(void *context, unsigned int reg, unsigned int *val) { struct regmap_mmio_context *ctx = context; - unsigned int offset; int ret; - regmap_mmio_regsize_check(reg_size); - if (!IS_ERR(ctx->clk)) { ret = clk_enable(ctx->clk); if (ret < 0) return ret; } - offset = regmap_mmio_get_offset(reg, reg_size); - - while (val_size) { - switch (ctx->val_bytes) { - case 1: - *(u8 *)val = __raw_readb(ctx->regs + offset); - break; - case 2: - *(u16 *)val = __raw_readw(ctx->regs + offset); - break; - case 4: - *(u32 *)val = __raw_readl(ctx->regs + offset); - break; -#ifdef CONFIG_64BIT - case 8: - *(u64 *)val = __raw_readq(ctx->regs + offset); - break; -#endif - default: - /* Should be caught by regmap_mmio_check_config */ - BUG(); - } - val_size -= ctx->val_bytes; - val += ctx->val_bytes; - offset += ctx->val_bytes; - } + *val = ctx->reg_read(ctx, reg); if (!IS_ERR(ctx->clk)) clk_disable(ctx->clk); @@ -232,14 +207,11 @@ static void regmap_mmio_free_context(void *context) kfree(context); } -static struct regmap_bus regmap_mmio = { +static const struct regmap_bus regmap_mmio = { .fast_io = true, - .write = regmap_mmio_write, - .gather_write = regmap_mmio_gather_write, - .read = regmap_mmio_read, + .reg_write = regmap_mmio_write, + .reg_read = regmap_mmio_read, .free_context = regmap_mmio_free_context, - .reg_format_endian_default = REGMAP_ENDIAN_NATIVE, - .val_format_endian_default = REGMAP_ENDIAN_NATIVE, }; static struct regmap_mmio_context *regmap_mmio_gen_context(struct device *dev, @@ -265,24 +237,71 @@ static struct regmap_mmio_context *regmap_mmio_gen_context(struct device *dev, if (config->reg_stride < min_stride) return ERR_PTR(-EINVAL); - switch (config->reg_format_endian) { - case REGMAP_ENDIAN_DEFAULT: - case REGMAP_ENDIAN_NATIVE: - break; - default: - return ERR_PTR(-EINVAL); - } - ctx = kzalloc(sizeof(*ctx), GFP_KERNEL); if (!ctx) return ERR_PTR(-ENOMEM); ctx->regs = regs; ctx->val_bytes = config->val_bits / 8; - ctx->reg_bytes = config->reg_bits / 8; - ctx->pad_bytes = config->pad_bits / 8; ctx->clk = ERR_PTR(-ENODEV); + switch (config->reg_format_endian) { + case REGMAP_ENDIAN_DEFAULT: + case REGMAP_ENDIAN_LITTLE: +#ifdef __LITTLE_ENDIAN + case REGMAP_ENDIAN_NATIVE: +#endif + switch (config->val_bits) { + case 8: + ctx->reg_read = regmap_mmio_read8; + ctx->reg_write = regmap_mmio_write8; + break; + case 16: + ctx->reg_read = regmap_mmio_read16le; + ctx->reg_write = regmap_mmio_write16le; + break; + case 32: + ctx->reg_read = regmap_mmio_read32le; + ctx->reg_write = regmap_mmio_write32le; + break; +#ifdef CONFIG_64BIT + case 64: + ctx->reg_read = regmap_mmio_read64le; + ctx->reg_write = regmap_mmio_write64le; + break; +#endif + default: + ret = -EINVAL; + goto err_free; + } + break; + case REGMAP_ENDIAN_BIG: +#ifdef __BIG_ENDIAN + case REGMAP_ENDIAN_NATIVE: +#endif + switch (config->val_bits) { + case 8: + ctx->reg_read = regmap_mmio_read8; + ctx->reg_write = regmap_mmio_write8; + break; + case 16: + ctx->reg_read = regmap_mmio_read16be; + ctx->reg_write = regmap_mmio_write16be; + break; + case 32: + ctx->reg_read = regmap_mmio_read32be; + ctx->reg_write = regmap_mmio_write32be; + break; + default: + ret = -EINVAL; + goto err_free; + } + break; + default: + ret = -EINVAL; + goto err_free; + } + if (clk_id == NULL) return ctx; -- cgit v1.2.3 From bb2bb45d1be28987e6cb50f50e4819795537ab83 Mon Sep 17 00:00:00 2001 From: Mark Brown Date: Mon, 1 Feb 2016 21:09:14 +0000 Subject: regmap: Return an error if a caller attempts to do an unsupported raw read regmaps without raw I/O access can't implement raw I/O operations, return an error if someone tries to do that rather than crashing. Signed-off-by: Mark Brown --- drivers/base/regmap/regmap.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'drivers/base') diff --git a/drivers/base/regmap/regmap.c b/drivers/base/regmap/regmap.c index 343263449aff..e2f68807d970 100644 --- a/drivers/base/regmap/regmap.c +++ b/drivers/base/regmap/regmap.c @@ -2255,6 +2255,9 @@ static int _regmap_raw_read(struct regmap *map, unsigned int reg, void *val, WARN_ON(!map->bus); + if (!map->bus || !map->bus->read) + return -EINVAL; + range = _regmap_range_lookup(map, reg); if (range) { ret = _regmap_select_page(map, ®, range, -- cgit v1.2.3 From 3245d460a1eb55b5c3ca31dde7b5c5ac71546edf Mon Sep 17 00:00:00 2001 From: Mark Brown Date: Tue, 2 Feb 2016 10:16:51 -0200 Subject: regmap: cache: Fall back to register by register read for cache defaults If we are unable to read the cache defaults for a regmap then fall back on attempting to read them word by word. This is going to be painfully slow for large regmaps but might be adequate for smaller ones. Signed-off-by: Mark Brown [maciej: Use cache_bypass around read and skipping of unreadable regs] Signed-off-by: Maciej S. Szmigiero Signed-off-by: Fabio Estevam Tested-by: Fabio Estevam Signed-off-by: Mark Brown --- drivers/base/regmap/regcache.c | 41 ++++++++++++++++++++++++++++++----------- 1 file changed, 30 insertions(+), 11 deletions(-) (limited to 'drivers/base') diff --git a/drivers/base/regmap/regcache.c b/drivers/base/regmap/regcache.c index 348be3a35410..cccceb599b02 100644 --- a/drivers/base/regmap/regcache.c +++ b/drivers/base/regmap/regcache.c @@ -30,7 +30,7 @@ static int regcache_hw_init(struct regmap *map) int i, j; int ret; int count; - unsigned int val; + unsigned int reg, val; void *tmp_buf; if (!map->num_reg_defaults_raw) @@ -67,27 +67,46 @@ static int regcache_hw_init(struct regmap *map) ret = regmap_raw_read(map, 0, tmp_buf, map->num_reg_defaults_raw); map->cache_bypass = cache_bypass; - if (ret < 0) - goto err_cache_free; - - map->reg_defaults_raw = tmp_buf; - map->cache_free = 1; + if (ret == 0) { + map->reg_defaults_raw = tmp_buf; + map->cache_free = 1; + } else { + kfree(tmp_buf); + } } /* fill the reg_defaults */ for (i = 0, j = 0; i < map->num_reg_defaults_raw; i++) { - if (regmap_volatile(map, i * map->reg_stride)) + reg = i * map->reg_stride; + + if (!regmap_readable(map, reg)) continue; - val = regcache_get_val(map, map->reg_defaults_raw, i); - map->reg_defaults[j].reg = i * map->reg_stride; + + if (regmap_volatile(map, reg)) + continue; + + if (map->reg_defaults_raw) { + val = regcache_get_val(map, map->reg_defaults_raw, i); + } else { + bool cache_bypass = map->cache_bypass; + + map->cache_bypass = true; + ret = regmap_read(map, reg, &val); + map->cache_bypass = cache_bypass; + if (ret != 0) { + dev_err(map->dev, "Failed to read %d: %d\n", + reg, ret); + goto err_free; + } + } + + map->reg_defaults[j].reg = reg; map->reg_defaults[j].def = val; j++; } return 0; -err_cache_free: - kfree(tmp_buf); err_free: kfree(map->reg_defaults); -- cgit v1.2.3