/*
 * Copyright 2017, Data61
 * Commonwealth Scientific and Industrial Research Organisation (CSIRO)
 * ABN 41 687 119 230.
 *
 * This software may be distributed and modified according to the terms of
 * the BSD 2-Clause license. Note that NO WARRANTY is provided.
 * See "LICENSE_BSD2.txt" for details.
 *
 * @TAG(DATA61_BSD)
 */

#pragma pack(push,1)

/* eXtended System Descriptor Table "XSDT" */
typedef struct acpi_xsdt {
    acpi_header_t  header;
    /* access via inline functions */
//    uint64_t        entry[];
} acpi_xsdt_t;

#pragma pack(pop)

/* retrieve the number of entries in an xsdt table */
static inline int
acpi_xsdt_entry_count(acpi_xsdt_t* t)
{
    return (t->header.length - sizeof(*t)) / sizeof(uint64_t);
}

/* Retrieve the location of the first item in the list */
static inline uint64_t*
acpi_xsdt_first(acpi_xsdt_t* hdr)
{
    return (uint64_t*)(hdr + 1);
}

/* Retrieve the location of the next item in the list */
static inline uint64_t*
acpi_xsdt_next(acpi_xsdt_t* hdr, uint64_t* cur)
{
    char* next = (char*)(cur + 1);
    char* end = (char*)hdr + hdr->header.length;
    if (next < end) {
        return (uint64_t*)next;
    } else {
        return NULL;
    }
}