/* Public domain. */

#ifndef _LINUX_IOSYS_MAP_H
#define _LINUX_IOSYS_MAP_H

#include <linux/io.h>
#include <linux/string.h>

struct iosys_map {
        union {
                void *vaddr_iomem;
                void *vaddr;
        };
        bool is_iomem;
        bus_space_handle_t bsh;
        bus_size_t size;
};

static inline void
iosys_map_incr(struct iosys_map *ism, size_t n)
{
        if (ism->is_iomem)
                ism->vaddr_iomem += n;
        else
                ism->vaddr += n;
}

static inline void
iosys_map_memcpy_to(struct iosys_map *ism, size_t off, const void *src,
    size_t len)
{
        if (ism->is_iomem)
                memcpy_toio(ism->vaddr_iomem + off, src, len);
        else
                memcpy(ism->vaddr + off, src, len);
}

static inline void
iosys_map_memset(struct iosys_map *ism, size_t off, int c, size_t len)
{
        if (ism->is_iomem)
                memset_io(ism->vaddr_iomem + off, c, len);
        else
                memset(ism->vaddr + off, c, len);
}

static inline bool
iosys_map_is_null(const struct iosys_map *ism)
{
        if (ism->is_iomem)
                return (ism->vaddr_iomem == NULL);
        else
                return (ism->vaddr == NULL);
}

static inline bool
iosys_map_is_set(const struct iosys_map *ism)
{
        if (ism->is_iomem)
                return (ism->vaddr_iomem != NULL);
        else
                return (ism->vaddr != NULL);
}

static inline void
iosys_map_clear(struct iosys_map *ism)
{
        if (ism->is_iomem) {
                ism->vaddr_iomem = NULL;
                ism->is_iomem = false;
        } else {
                ism->vaddr = NULL;
        }
}

static inline void
iosys_map_set_vaddr_iomem(struct iosys_map *ism, void *addr)
{
        ism->vaddr_iomem = addr;
        ism->is_iomem = true;
}

static inline void
iosys_map_set_vaddr(struct iosys_map *ism, void *addr)
{
        ism->vaddr = addr;
        ism->is_iomem = false;
}

static inline struct iosys_map
IOSYS_MAP_INIT_OFFSET(struct iosys_map *ism, size_t off)
{
        struct iosys_map nism = *ism;
        iosys_map_incr(&nism, off);
        return nism;
}

#if defined(__STDC_VERSION__) && __STDC_VERSION__ >= 201112

#define iosys_map_rd(_ism, _o, _t) ({                                   \
        _t v;                                                           \
        if ((_ism)->is_iomem) {                                         \
                void *addr = (_ism)->vaddr_iomem + (_o);                \
                v = _Generic(v,                                         \
                    uint8_t : ioread8(addr),                            \
                    uint16_t: ioread16(addr),                           \
                    uint32_t: ioread32(addr),                           \
                    uint64_t: ioread64(addr));                          \
        } else                                                          \
                v = READ_ONCE(*(_t *)((_ism)->vaddr + (_o)));           \
        v;                                                              \
})

#define iosys_map_wr(_ism, _o, _t, _v) ({                               \
        _t v = (_v);                                                    \
        if ((_ism)->is_iomem) {                                         \
                void *addr = (_ism)->vaddr_iomem + (_o);                \
                _Generic(v,                                             \
                    uint8_t : iowrite8(v, addr),                        \
                    uint16_t: iowrite16(v, addr),                       \
                    uint32_t: iowrite32(v, addr),                       \
                    uint64_t: iowrite64(v, addr));                      \
        } else                                                          \
                WRITE_ONCE(*(_t *)((_ism)->vaddr + (_o)), v);           \
})

#define iosys_map_rd_field(_ism, _o, _t, _f) ({                         \
        _t *t;                                                          \
        iosys_map_rd(_ism, _o + offsetof(_t, _f), __typeof(t->_f));     \
})

#define iosys_map_wr_field(_ism, _o, _t, _f, _v) ({                     \
        _t *t;                                                          \
        iosys_map_wr(_ism, _o + offsetof(_t, _f), __typeof(t->_f), _v); \
})

#endif /* C11 */

#endif