regions: add memory region device support

Provide common code for using memory-backed region devices.
This allows in-memory buffers to act as a region device.

Change-Id: I266cd07bbfa16a427c2b31c512e7c87b77f47718
Signed-off-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-on: http://review.coreboot.org/9131
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
This commit is contained in:
Aaron Durbin 2015-03-27 01:03:45 -05:00
parent 127525c772
commit b419c1a87c
2 changed files with 61 additions and 0 deletions

View File

@ -97,4 +97,23 @@ static inline size_t region_sz(const struct region *r)
return r->size;
}
struct mem_region_device {
char *base;
struct region_device rdev;
};
/* Iniitalize at runtime a mem_region_device. This would be used when
* the base and size are dynamic or can't be known during linking. */
void mem_region_device_init(struct mem_region_device *mdev, void *base,
size_t size);
extern const struct region_device_ops mem_rdev_ops;
/* Statically initialize mem_region_device. */
#define MEM_REGION_DEV_INIT(base_, size_) \
{ \
.base = (void *)(base_), \
.rdev = REGION_DEV_INIT(&mem_rdev_ops, 0, (size_)), \
}
#endif /* _REGION_H_ */

View File

@ -119,3 +119,45 @@ int rdev_chain(struct region_device *child, const struct region_device *parent,
return 0;
}
void mem_region_device_init(struct mem_region_device *mdev, void *base,
size_t size)
{
memset(mdev, 0, sizeof(*mdev));
mdev->base = base;
mdev->rdev.ops = &mem_rdev_ops;
mdev->rdev.region.size = size;
}
static void *mdev_mmap(const struct region_device *rd, size_t offset,
size_t size)
{
const struct mem_region_device *mdev;
mdev = container_of(rd, typeof(*mdev), rdev);
return &mdev->base[offset];
}
static int mdev_munmap(const struct region_device *rd, void *mapping)
{
return 0;
}
static ssize_t mdev_readat(const struct region_device *rd, void *b,
size_t offset, size_t size)
{
const struct mem_region_device *mdev;
mdev = container_of(rd, typeof(*mdev), rdev);
memcpy(b, &mdev->base[offset], size);
return size;
}
const struct region_device_ops mem_rdev_ops = {
.mmap = mdev_mmap,
.munmap = mdev_munmap,
.readat = mdev_readat,
};