diff options
Diffstat (limited to 'drivers/base/regmap/regmap-mmio.c')
| -rw-r--r-- | drivers/base/regmap/regmap-mmio.c | 612 |
1 files changed, 612 insertions, 0 deletions
diff --git a/drivers/base/regmap/regmap-mmio.c b/drivers/base/regmap/regmap-mmio.c new file mode 100644 index 0000000000..99d7fd85ca --- /dev/null +++ b/drivers/base/regmap/regmap-mmio.c @@ -0,0 +1,612 @@ +// SPDX-License-Identifier: GPL-2.0 +// +// Register map access API - MMIO support +// +// Copyright (c) 2012, NVIDIA CORPORATION. All rights reserved. + +#include <linux/clk.h> +#include <linux/err.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/regmap.h> +#include <linux/slab.h> +#include <linux/swab.h> + +#include "internal.h" + +struct regmap_mmio_context { + void __iomem *regs; + unsigned int val_bytes; + bool big_endian; + + bool attached_clk; + struct clk *clk; + + 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) +{ + switch (reg_bits) { + case 8: + case 16: + case 32: + return 0; + default: + return -EINVAL; + } +} + +static int regmap_mmio_get_min_stride(size_t val_bits) +{ + int min_stride; + + switch (val_bits) { + case 8: + /* The core treats 0 as 1 */ + min_stride = 0; + break; + case 16: + min_stride = 2; + break; + case 32: + min_stride = 4; + break; + default: + return -EINVAL; + } + + return min_stride; +} + +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_write8_relaxed(struct regmap_mmio_context *ctx, + unsigned int reg, + unsigned int val) +{ + writeb_relaxed(val, ctx->regs + reg); +} + +static void regmap_mmio_iowrite8(struct regmap_mmio_context *ctx, + unsigned int reg, unsigned int val) +{ + iowrite8(val, ctx->regs + reg); +} + +static void regmap_mmio_write16le(struct regmap_mmio_context *ctx, + unsigned int reg, + unsigned int val) +{ + writew(val, ctx->regs + reg); +} + +static void regmap_mmio_write16le_relaxed(struct regmap_mmio_context *ctx, + unsigned int reg, + unsigned int val) +{ + writew_relaxed(val, ctx->regs + reg); +} + +static void regmap_mmio_iowrite16le(struct regmap_mmio_context *ctx, + unsigned int reg, unsigned int val) +{ + iowrite16(val, ctx->regs + reg); +} + +static void regmap_mmio_write16be(struct regmap_mmio_context *ctx, + unsigned int reg, + unsigned int val) +{ + writew(swab16(val), ctx->regs + reg); +} + +static void regmap_mmio_iowrite16be(struct regmap_mmio_context *ctx, + unsigned int reg, unsigned int val) +{ + 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_write32le_relaxed(struct regmap_mmio_context *ctx, + unsigned int reg, + unsigned int val) +{ + writel_relaxed(val, ctx->regs + reg); +} + +static void regmap_mmio_iowrite32le(struct regmap_mmio_context *ctx, + unsigned int reg, unsigned int val) +{ + iowrite32(val, ctx->regs + reg); +} + +static void regmap_mmio_write32be(struct regmap_mmio_context *ctx, + unsigned int reg, + unsigned int val) +{ + writel(swab32(val), ctx->regs + reg); +} + +static void regmap_mmio_iowrite32be(struct regmap_mmio_context *ctx, + unsigned int reg, unsigned int val) +{ + iowrite32be(val, ctx->regs + reg); +} + +static int regmap_mmio_write(void *context, unsigned int reg, unsigned int val) +{ + struct regmap_mmio_context *ctx = context; + int ret; + + if (!IS_ERR(ctx->clk)) { + ret = clk_enable(ctx->clk); + if (ret < 0) + return ret; + } + + ctx->reg_write(ctx, reg, val); + + if (!IS_ERR(ctx->clk)) + clk_disable(ctx->clk); + + return 0; +} + +static int regmap_mmio_noinc_write(void *context, unsigned int reg, + const void *val, size_t val_count) +{ + struct regmap_mmio_context *ctx = context; + int ret = 0; + int i; + + if (!IS_ERR(ctx->clk)) { + ret = clk_enable(ctx->clk); + if (ret < 0) + return ret; + } + + /* + * There are no native, assembly-optimized write single register + * operations for big endian, so fall back to emulation if this + * is needed. (Single bytes are fine, they are not affected by + * endianness.) + */ + if (ctx->big_endian && (ctx->val_bytes > 1)) { + switch (ctx->val_bytes) { + case 2: + { + const u16 *valp = (const u16 *)val; + for (i = 0; i < val_count; i++) + writew(swab16(valp[i]), ctx->regs + reg); + goto out_clk; + } + case 4: + { + const u32 *valp = (const u32 *)val; + for (i = 0; i < val_count; i++) + writel(swab32(valp[i]), ctx->regs + reg); + goto out_clk; + } + default: + ret = -EINVAL; + goto out_clk; + } + } + + switch (ctx->val_bytes) { + case 1: + writesb(ctx->regs + reg, (const u8 *)val, val_count); + break; + case 2: + writesw(ctx->regs + reg, (const u16 *)val, val_count); + break; + case 4: + writesl(ctx->regs + reg, (const u32 *)val, val_count); + break; + default: + ret = -EINVAL; + break; + } + +out_clk: + if (!IS_ERR(ctx->clk)) + clk_disable(ctx->clk); + + return ret; +} + +static unsigned int regmap_mmio_read8(struct regmap_mmio_context *ctx, + unsigned int reg) +{ + return readb(ctx->regs + reg); +} + +static unsigned int regmap_mmio_read8_relaxed(struct regmap_mmio_context *ctx, + unsigned int reg) +{ + return readb_relaxed(ctx->regs + reg); +} + +static unsigned int regmap_mmio_ioread8(struct regmap_mmio_context *ctx, + unsigned int reg) +{ + return ioread8(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_read16le_relaxed(struct regmap_mmio_context *ctx, + unsigned int reg) +{ + return readw_relaxed(ctx->regs + reg); +} + +static unsigned int regmap_mmio_ioread16le(struct regmap_mmio_context *ctx, + unsigned int reg) +{ + return ioread16(ctx->regs + reg); +} + +static unsigned int regmap_mmio_read16be(struct regmap_mmio_context *ctx, + unsigned int reg) +{ + return swab16(readw(ctx->regs + reg)); +} + +static unsigned int regmap_mmio_ioread16be(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); +} + +static unsigned int regmap_mmio_read32le_relaxed(struct regmap_mmio_context *ctx, + unsigned int reg) +{ + return readl_relaxed(ctx->regs + reg); +} + +static unsigned int regmap_mmio_ioread32le(struct regmap_mmio_context *ctx, + unsigned int reg) +{ + return ioread32(ctx->regs + reg); +} + +static unsigned int regmap_mmio_read32be(struct regmap_mmio_context *ctx, + unsigned int reg) +{ + return swab32(readl(ctx->regs + reg)); +} + +static unsigned int regmap_mmio_ioread32be(struct regmap_mmio_context *ctx, + unsigned int reg) +{ + return ioread32be(ctx->regs + reg); +} + +static int regmap_mmio_read(void *context, unsigned int reg, unsigned int *val) +{ + struct regmap_mmio_context *ctx = context; + int ret; + + if (!IS_ERR(ctx->clk)) { + ret = clk_enable(ctx->clk); + if (ret < 0) + return ret; + } + + *val = ctx->reg_read(ctx, reg); + + if (!IS_ERR(ctx->clk)) + clk_disable(ctx->clk); + + return 0; +} + +static int regmap_mmio_noinc_read(void *context, unsigned int reg, + void *val, size_t val_count) +{ + struct regmap_mmio_context *ctx = context; + int ret = 0; + + if (!IS_ERR(ctx->clk)) { + ret = clk_enable(ctx->clk); + if (ret < 0) + return ret; + } + + switch (ctx->val_bytes) { + case 1: + readsb(ctx->regs + reg, (u8 *)val, val_count); + break; + case 2: + readsw(ctx->regs + reg, (u16 *)val, val_count); + break; + case 4: + readsl(ctx->regs + reg, (u32 *)val, val_count); + break; + default: + ret = -EINVAL; + goto out_clk; + } + + /* + * There are no native, assembly-optimized write single register + * operations for big endian, so fall back to emulation if this + * is needed. (Single bytes are fine, they are not affected by + * endianness.) + */ + if (ctx->big_endian && (ctx->val_bytes > 1)) { + switch (ctx->val_bytes) { + case 2: + swab16_array(val, val_count); + break; + case 4: + swab32_array(val, val_count); + break; + default: + ret = -EINVAL; + break; + } + } + +out_clk: + if (!IS_ERR(ctx->clk)) + clk_disable(ctx->clk); + + return ret; +} + + +static void regmap_mmio_free_context(void *context) +{ + struct regmap_mmio_context *ctx = context; + + if (!IS_ERR(ctx->clk)) { + clk_unprepare(ctx->clk); + if (!ctx->attached_clk) + clk_put(ctx->clk); + } + kfree(context); +} + +static const struct regmap_bus regmap_mmio = { + .fast_io = true, + .reg_write = regmap_mmio_write, + .reg_read = regmap_mmio_read, + .reg_noinc_write = regmap_mmio_noinc_write, + .reg_noinc_read = regmap_mmio_noinc_read, + .free_context = regmap_mmio_free_context, + .val_format_endian_default = REGMAP_ENDIAN_LITTLE, +}; + +static struct regmap_mmio_context *regmap_mmio_gen_context(struct device *dev, + const char *clk_id, + void __iomem *regs, + const struct regmap_config *config) +{ + struct regmap_mmio_context *ctx; + int min_stride; + int ret; + + ret = regmap_mmio_regbits_check(config->reg_bits); + if (ret) + return ERR_PTR(ret); + + if (config->pad_bits) + return ERR_PTR(-EINVAL); + + min_stride = regmap_mmio_get_min_stride(config->val_bits); + if (min_stride < 0) + return ERR_PTR(min_stride); + + if (config->reg_stride && config->reg_stride < min_stride) + return ERR_PTR(-EINVAL); + + if (config->use_relaxed_mmio && config->io_port) + 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->clk = ERR_PTR(-ENODEV); + + switch (regmap_get_val_endian(dev, ®map_mmio, config)) { + case REGMAP_ENDIAN_DEFAULT: + case REGMAP_ENDIAN_LITTLE: +#ifdef __LITTLE_ENDIAN + case REGMAP_ENDIAN_NATIVE: +#endif + switch (config->val_bits) { + case 8: + if (config->io_port) { + ctx->reg_read = regmap_mmio_ioread8; + ctx->reg_write = regmap_mmio_iowrite8; + } else if (config->use_relaxed_mmio) { + ctx->reg_read = regmap_mmio_read8_relaxed; + ctx->reg_write = regmap_mmio_write8_relaxed; + } else { + ctx->reg_read = regmap_mmio_read8; + ctx->reg_write = regmap_mmio_write8; + } + break; + case 16: + if (config->io_port) { + ctx->reg_read = regmap_mmio_ioread16le; + ctx->reg_write = regmap_mmio_iowrite16le; + } else if (config->use_relaxed_mmio) { + ctx->reg_read = regmap_mmio_read16le_relaxed; + ctx->reg_write = regmap_mmio_write16le_relaxed; + } else { + ctx->reg_read = regmap_mmio_read16le; + ctx->reg_write = regmap_mmio_write16le; + } + break; + case 32: + if (config->io_port) { + ctx->reg_read = regmap_mmio_ioread32le; + ctx->reg_write = regmap_mmio_iowrite32le; + } else if (config->use_relaxed_mmio) { + ctx->reg_read = regmap_mmio_read32le_relaxed; + ctx->reg_write = regmap_mmio_write32le_relaxed; + } else { + ctx->reg_read = regmap_mmio_read32le; + ctx->reg_write = regmap_mmio_write32le; + } + break; + default: + ret = -EINVAL; + goto err_free; + } + break; + case REGMAP_ENDIAN_BIG: +#ifdef __BIG_ENDIAN + case REGMAP_ENDIAN_NATIVE: +#endif + ctx->big_endian = true; + switch (config->val_bits) { + case 8: + if (config->io_port) { + ctx->reg_read = regmap_mmio_ioread8; + ctx->reg_write = regmap_mmio_iowrite8; + } else { + ctx->reg_read = regmap_mmio_read8; + ctx->reg_write = regmap_mmio_write8; + } + break; + case 16: + if (config->io_port) { + ctx->reg_read = regmap_mmio_ioread16be; + ctx->reg_write = regmap_mmio_iowrite16be; + } else { + ctx->reg_read = regmap_mmio_read16be; + ctx->reg_write = regmap_mmio_write16be; + } + break; + case 32: + if (config->io_port) { + ctx->reg_read = regmap_mmio_ioread32be; + ctx->reg_write = regmap_mmio_iowrite32be; + } else { + 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; + + ctx->clk = clk_get(dev, clk_id); + if (IS_ERR(ctx->clk)) { + ret = PTR_ERR(ctx->clk); + goto err_free; + } + + ret = clk_prepare(ctx->clk); + if (ret < 0) { + clk_put(ctx->clk); + goto err_free; + } + + return ctx; + +err_free: + kfree(ctx); + + return ERR_PTR(ret); +} + +struct regmap *__regmap_init_mmio_clk(struct device *dev, const char *clk_id, + void __iomem *regs, + const struct regmap_config *config, + struct lock_class_key *lock_key, + const char *lock_name) +{ + struct regmap_mmio_context *ctx; + + ctx = regmap_mmio_gen_context(dev, clk_id, regs, config); + if (IS_ERR(ctx)) + return ERR_CAST(ctx); + + return __regmap_init(dev, ®map_mmio, ctx, config, + lock_key, lock_name); +} +EXPORT_SYMBOL_GPL(__regmap_init_mmio_clk); + +struct regmap *__devm_regmap_init_mmio_clk(struct device *dev, + const char *clk_id, + void __iomem *regs, + const struct regmap_config *config, + struct lock_class_key *lock_key, + const char *lock_name) +{ + struct regmap_mmio_context *ctx; + + ctx = regmap_mmio_gen_context(dev, clk_id, regs, config); + if (IS_ERR(ctx)) + return ERR_CAST(ctx); + + return __devm_regmap_init(dev, ®map_mmio, ctx, config, + lock_key, lock_name); +} +EXPORT_SYMBOL_GPL(__devm_regmap_init_mmio_clk); + +int regmap_mmio_attach_clk(struct regmap *map, struct clk *clk) +{ + struct regmap_mmio_context *ctx = map->bus_context; + + ctx->clk = clk; + ctx->attached_clk = true; + + return clk_prepare(ctx->clk); +} +EXPORT_SYMBOL_GPL(regmap_mmio_attach_clk); + +void regmap_mmio_detach_clk(struct regmap *map) +{ + struct regmap_mmio_context *ctx = map->bus_context; + + clk_unprepare(ctx->clk); + + ctx->attached_clk = false; + ctx->clk = NULL; +} +EXPORT_SYMBOL_GPL(regmap_mmio_detach_clk); + +MODULE_LICENSE("GPL v2"); |