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/*
* This file is part of the coreboot project.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; version 2 of the License.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#ifndef _REGION_H_
#define _REGION_H_
#include <sys/types.h>
#include <stdint.h>
#include <stddef.h>
#include <commonlib/mem_pool.h>
/*
* Region support.
*
* Regions are intended to abstract away the access mechanisms for blocks of
* data. This could be SPI, eMMC, or a memory region as the backing store.
* They are accessed through a region_device. Subregions can be made by
* chaining together multiple region_devices.
*/
struct region_device;
/*
* Returns NULL on error otherwise a buffer is returned with the contents of
* the requested data at offset of size.
*/
void *rdev_mmap(const struct region_device *rd, size_t offset, size_t size);
/* Unmap a previously mapped area. Returns 0 on success, < 0 on error. */
int rdev_munmap(const struct region_device *rd, void *mapping);
/*
* Returns < 0 on error otherwise returns size of data read at provided
* offset filling in the buffer passed.
*/
ssize_t rdev_readat(const struct region_device *rd, void *b, size_t offset,
size_t size);
/*
* Returns < 0 on error otherwise returns size of data wrote at provided
* offset from the buffer passed.
*/
ssize_t rdev_writeat(const struct region_device *rd, const void *b,
size_t offset, size_t size);
/*
* Returns < 0 on error otherwise returns size of data erased.
* If eraseat ops is not defined it returns size which indicates
* that operation was successful.
*/
ssize_t rdev_eraseat(const struct region_device *rd, size_t offset,
size_t size);
/****************************************
* Implementation of a region device *
****************************************/
/*
* Create a child region of the parent provided the sub-region is within
* the parent's region. Returns < 0 on error otherwise 0 on success. Note
* that the child device only calls through the parent's operations.
*/
int rdev_chain(struct region_device *child, const struct region_device *parent,
size_t offset, size_t size);
/* A region_device operations. */
struct region_device_ops {
void *(*mmap)(const struct region_device *, size_t, size_t);
int (*munmap)(const struct region_device *, void *);
ssize_t (*readat)(const struct region_device *, void *, size_t, size_t);
ssize_t (*writeat)(const struct region_device *, const void *, size_t,
size_t);
ssize_t (*eraseat)(const struct region_device *, size_t, size_t);
};
struct region {
size_t offset;
size_t size;
};
struct region_device {
const struct region_device *root;
const struct region_device_ops *ops;
struct region region;
};
#define REGION_DEV_INIT(ops_, offset_, size_) \
{ \
.root = NULL, \
.ops = (ops_), \
.region = { \
.offset = (offset_), \
.size = (size_), \
}, \
}
/* Helper to dynamically initialize region device. */
void region_device_init(struct region_device *rdev,
const struct region_device_ops *ops, size_t offset,
size_t size);
/* Return 1 if child is subregion of parent, else 0. */
int region_is_subregion(const struct region *p, const struct region *c);
static inline size_t region_offset(const struct region *r)
{
return r->offset;
}
static inline size_t region_sz(const struct region *r)
{
return r->size;
}
static inline size_t region_end(const struct region *r)
{
return region_offset(r) + region_sz(r);
}
static inline const struct region *region_device_region(
const struct region_device *rdev)
{
return &rdev->region;
}
static inline size_t region_device_sz(const struct region_device *rdev)
{
return region_sz(region_device_region(rdev));
}
static inline size_t region_device_offset(const struct region_device *rdev)
{
return region_offset(region_device_region(rdev));
}
static inline size_t region_device_end(const struct region_device *rdev)
{
return region_end(region_device_region(rdev));
}
/* Memory map entire region device. Same semantics as rdev_mmap() above. */
static inline void *rdev_mmap_full(const struct region_device *rd)
{
return rdev_mmap(rd, 0, region_device_sz(rd));
}
static inline int rdev_chain_full(struct region_device *child,
const struct region_device *parent)
{
/* Chain full size of parent. */
return rdev_chain(child, parent, 0, region_device_sz(parent));
}
/*
* Compute relative offset of the child (c) w.r.t. the parent (p). Returns < 0
* when child is not within the parent's region.
*/
ssize_t rdev_relative_offset(const struct region_device *p,
const struct region_device *c);
struct mem_region_device {
char *base;
struct region_device rdev;
};
/* Initialize at runtime a mem_region_device. This would be used when
* the base and size are dynamic or can't be known during linking.
* There are two variants: read-only and read-write. */
void mem_region_device_ro_init(struct mem_region_device *mdev, void *base,
size_t size);
void mem_region_device_rw_init(struct mem_region_device *mdev, void *base,
size_t size);
extern const struct region_device_ops mem_rdev_ro_ops;
extern const struct region_device_ops mem_rdev_rw_ops;
/* Statically initialize mem_region_device. */
#define MEM_REGION_DEV_INIT(base_, size_, ops_) \
{ \
.base = (void *)(base_), \
.rdev = REGION_DEV_INIT((ops_), 0, (size_)), \
}
#define MEM_REGION_DEV_RO_INIT(base_, size_) \
MEM_REGION_DEV_INIT(base_, size_, &mem_rdev_ro_ops) \
#define MEM_REGION_DEV_RW_INIT(base_, size_) \
MEM_REGION_DEV_INIT(base_, size_, &mem_rdev_rw_ops) \
struct mmap_helper_region_device {
struct mem_pool pool;
struct region_device rdev;
};
#define MMAP_HELPER_REGION_INIT(ops_, offset_, size_) \
{ \
.rdev = REGION_DEV_INIT((ops_), (offset_), (size_)), \
}
void mmap_helper_device_init(struct mmap_helper_region_device *mdev,
void *cache, size_t cache_size);
void *mmap_helper_rdev_mmap(const struct region_device *, size_t, size_t);
int mmap_helper_rdev_munmap(const struct region_device *, void *);
/* A translated region device provides the ability to publish a region device
* in one address space and use an access mechanism within another address
* space. The sub region is the window within the 1st address space and
* the request is modified prior to accessing the second address space
* provided by access_dev. */
struct xlate_region_device {
const struct region_device *access_dev;
struct region sub_region;
struct region_device rdev;
};
extern const struct region_device_ops xlate_rdev_ro_ops;
extern const struct region_device_ops xlate_rdev_rw_ops;
#define XLATE_REGION_DEV_INIT(access_dev_, sub_offset_, sub_size_, \
parent_sz_, ops_) \
{ \
.access_dev = access_dev_, \
.sub_region = { \
.offset = (sub_offset_), \
.size = (sub_size_), \
}, \
.rdev = REGION_DEV_INIT((ops_), 0, (parent_sz_)), \
}
#define XLATE_REGION_DEV_RO_INIT(access_dev_, sub_offset_, sub_size_, \
parent_sz_) \
XLATE_REGION_DEV_INIT(access_dev_, sub_offset_, \
sub_size_, parent_sz_, &xlate_rdev_ro_ops), \
#define XLATE_REGION_DEV_RW_INIT(access_dev_, sub_offset_, sub_size_, \
parent_sz_) \
XLATE_REGION_DEV_INIT(access_dev_, sub_offset_, \
sub_size_, parent_sz_, &xlate_rdev_rw_ops), \
/* Helper to dynamically initialize xlate region device. */
void xlate_region_device_ro_init(struct xlate_region_device *xdev,
const struct region_device *access_dev,
size_t sub_offset, size_t sub_size,
size_t parent_size);
void xlate_region_device_rw_init(struct xlate_region_device *xdev,
const struct region_device *access_dev,
size_t sub_offset, size_t sub_size,
size_t parent_size);
/* This type can be used for incoherent access where the read and write
* operations are backed by separate drivers. An example is x86 systems
* with memory mapped media for reading but use a spi flash driver for
* writing. One needs to ensure using this object is appropriate in context. */
struct incoherent_rdev {
struct region_device rdev;
const struct region_device *read;
const struct region_device *write;
};
/* Initialize an incoherent_rdev based on the region as well as the read and
* write rdevs. The read and write rdevs should match in size to the passed
* in region. If not the initialization will fail returning NULL. Otherwise
* the function will return a pointer to the containing region_device to
* be used for region operations. Therefore, the lifetime of the returned
* pointer matches the lifetime of the incoherent_rdev object. Likewise,
* the lifetime of the read and write rdev need to match the lifetime of
* the incoherent_rdev object. */
const struct region_device *incoherent_rdev_init(struct incoherent_rdev *irdev,
const struct region *r,
const struct region_device *read,
const struct region_device *write);
#endif /* _REGION_H_ */