/*      $NetBSD: fdt_ddb.c,v 1.2 2021/03/06 13:21:26 skrll Exp $        */

/*-
 * Copyright (c) 2020 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by Nick Hudson
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */


#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: fdt_ddb.c,v 1.2 2021/03/06 13:21:26 skrll Exp $");

#include <sys/param.h>

#include <libfdt.h>
#include <dev/fdt/fdt_ddb.h>
#include <dev/fdt/fdtvar.h>

#define FDT_MAX_DEPTH   16

static bool
fdt_isprint(const void *data, int len)
{
        const uint8_t *c = (const uint8_t *)data;

        if (len == 0)
                return false;

        /* Count consecutive zeroes */
        int cz = 0;
        for (size_t j = 0; j < len; j++) {
                if (c[j] == '\0')
                        cz++;
                else if (isprint(c[j]))
                        cz = 0;
                else
                        return false;
                if (cz > 1)
                        return false;
        }
        return true;
}

static void
fdt_print_properties(const void *fdt, int node,
    void (*pr)(const char *, ...) __printflike(1, 2))
{
        int property;

        fdt_for_each_property_offset(property, fdt, node) {
                int len;
                const struct fdt_property *prop =
                    fdt_get_property_by_offset(fdt, property, &len);
                const char *name = fdt_string(fdt, fdt32_to_cpu(prop->nameoff));

                pr("    %s", name);
                if (len == 0) {
                        pr("\n");
                        continue;
                }
                if (fdt_isprint(prop->data, len)) {
                        const uint8_t *c = (const uint8_t *)prop->data;

                        pr(" = \"");
                        for (size_t j = 0; j < len; j++) {
                                if (c[j] == '\0') {
                                        if (j + 1 != len)
                                                pr("\", \"");
                                } else
                                        pr("%c", c[j]);
                        }
                        pr("\"\n");
                        continue;
                }
                if ((len % 4) == 0) {
                        const uint32_t *cell = (const uint32_t *)prop->data;
                        size_t count = len / sizeof(uint32_t);

                        pr(" = <");
                        for (size_t j = 0; j < count; j++) {
                                pr("%#" PRIx32 "%s", fdt32_to_cpu(cell[j]),
                                    (j != count - 1) ? " " : "");
                        }
                        pr(">\n");
                } else {
                        const uint8_t *byte = (const uint8_t *)prop->data;

                        pr(" = [");
                        for (size_t j = 0; j < len; j++) {
                                pr("%02x%s", byte[j],
                                   (j != len - 1) ? " " : "");
                        }
                        pr("]\n");
                }
        }
}


void
fdt_print(const void *addr, bool full,
    void (*pr)(const char *, ...) __printflike(1, 2))
{
        const void *fdt = addr;
        const char *pname[FDT_MAX_DEPTH] = { NULL };

        int error = fdt_check_header(fdt);
        if (error) {
                pr("Invalid FDT at %p\n", fdt);
                return;
        }

        int depth = 0;
        for (int node = fdt_path_offset(fdt, "/");
             node >= 0 && depth >= 0;
             node = fdt_next_node(fdt, node, &depth)) {
                const char *name = fdt_get_name(fdt, node, NULL);

                if (depth > FDT_MAX_DEPTH) {
                        pr("max depth exceeded: %d\n", depth);
                        continue;
                }
                pname[depth] = name;
                /*
                 * change conditional for when alternative root nodes
                 * can be specified
                 */
                if (depth == 0)
                        pr("/");
                for (size_t i = 1; i <= depth; i++) {
                        if (pname[i] == NULL)
                                break;
                        pr("/%s", pname[i]);
                }
                pr("\n");
                if (!full)
                        continue;
                fdt_print_properties(fdt, node, pr);
        }
}