Function pci_ofw_parse_ranges

components/drivers/pci/ofw.c:161–246

}

static rt_err_t pci_ofw_parse_ranges(struct rt_ofw_node *dev_np, const char *propname,
        int phy_addr_cells, int phy_size_cells, int cpu_addr_cells,
        struct rt_pci_bus_region **out_regions, rt_size_t *out_regions_nr)
{
    const fdt32_t *cell;
    rt_ssize_t total_cells;
    int groups, space_code;
    rt_uint32_t phy_addr[3];
    rt_uint64_t cpu_addr, phy_addr_size;

    *out_regions = RT_NULL;
    *out_regions_nr = 0;
    cell = rt_ofw_prop_read_raw(dev_np, propname, &total_cells);

    if (!cell)
    {
        return -RT_EEMPTY;
    }

    groups = total_cells / sizeof(*cell) / (phy_addr_cells + phy_size_cells + cpu_addr_cells);
    *out_regions = rt_malloc(groups * sizeof(struct rt_pci_bus_region));

    if (!*out_regions)
    {
        return -RT_ENOMEM;
    }

    for (int i = 0; i < groups; ++i)
    {
        /*
         * ranges:
         *  phys.hi  cell: npt000ss bbbbbbbb dddddfff rrrrrrrr
         *  phys.low cell: llllllll llllllll llllllll llllllll
         *  phys.mid cell: hhhhhhhh hhhhhhhh hhhhhhhh hhhhhhhh
         *
         *  n: relocatable region flag (doesn't play a role here)
         *  p: prefetchable (cacheable) region flag
         *  t: aliased address flag (doesn't play a role here)
         *  ss: space code
         *      00: configuration space
         *      01: I/O space
         *      10: 32 bit memory space
         *      11: 64 bit memory space
         *  bbbbbbbb: The PCI bus number
         *  ddddd: The device number
         *  fff: The function number. Used for multifunction PCI devices.
         *  rrrrrrrr: Register number; used for configuration cycles.
         */

        for (int j = 0; j < phy_addr_cells; ++j)
        {
            phy_addr[j] = rt_fdt_read_number(cell++, 1);
        }

        space_code = (phy_addr[0] >> 24) & 0x3;

        cpu_addr = rt_fdt_read_number(cell, cpu_addr_cells);
        cell += cpu_addr_cells;