blob: 99d7fd85ca7da98a812792e1818883fb4feda9bf [file] [log] [blame]
// 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, &regmap_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, &regmap_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, &regmap_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");