/*
 * Copyright (C) 2016 Google, Inc
 * Written by Simon Glass <sjg@chromium.org>
 *
 * SPDX-License-Identifier:     GPL-2.0+
 */

#include <common.h>
#include <errno.h>
#include <image.h>
#include <libfdt.h>
#include <spl.h>

static ulong fdt_getprop_u32(const void *fdt, int node, const char *prop)
{
        const u32 *cell;
        int len;

        cell = fdt_getprop(fdt, node, prop, &len);
        if (len != sizeof(*cell))
                return -1U;
        return fdt32_to_cpu(*cell);
}

static int spl_fit_select_fdt(const void *fdt, int images, int *fdt_offsetp)
{
        const char *name, *fdt_name;
        int conf, node, fdt_node;
        int len;

        *fdt_offsetp = 0;
        conf = fdt_path_offset(fdt, FIT_CONFS_PATH);
        if (conf < 0) {
                debug("%s: Cannot find /configurations node: %d\n", __func__,
                      conf);
                return -EINVAL;
        }
        for (node = fdt_first_subnode(fdt, conf);
             node >= 0;
             node = fdt_next_subnode(fdt, node)) {
                name = fdt_getprop(fdt, node, "description", &len);
                if (!name) {
#ifdef CONFIG_SPL_LIBCOMMON_SUPPORT
                        printf("%s: Missing FDT description in DTB\n",
                               __func__);
#endif
                        return -EINVAL;
                }
                if (board_fit_config_name_match(name))
                        continue;

                debug("Selecting config '%s'", name);
                fdt_name = fdt_getprop(fdt, node, FIT_FDT_PROP, &len);
                if (!fdt_name) {
                        debug("%s: Cannot find fdt name property: %d\n",
                              __func__, len);
                        return -EINVAL;
                }

                debug(", fdt '%s'\n", fdt_name);
                fdt_node = fdt_subnode_offset(fdt, images, fdt_name);
                if (fdt_node < 0) {
                        debug("%s: Cannot find fdt node '%s': %d\n",
                              __func__, fdt_name, fdt_node);
                        return -EINVAL;
                }

                *fdt_offsetp = fdt_getprop_u32(fdt, fdt_node, "data-offset");
                len = fdt_getprop_u32(fdt, fdt_node, "data-size");
                debug("FIT: Selected '%s'\n", name);

                return len;
        }

#ifdef CONFIG_SPL_LIBCOMMON_SUPPORT
        printf("No matching DT out of these options:\n");
        for (node = fdt_first_subnode(fdt, conf);
             node >= 0;
             node = fdt_next_subnode(fdt, node)) {
                name = fdt_getprop(fdt, node, "description", &len);
                printf("   %s\n", name);
        }
#endif

        return -ENOENT;
}

static int get_aligned_image_offset(struct spl_load_info *info, int offset)
{
        /*
         * If it is a FS read, get the first address before offset which is
         * aligned to ARCH_DMA_MINALIGN. If it is raw read return the
         * block number to which offset belongs.
         */
        if (info->filename)
                return offset & ~(ARCH_DMA_MINALIGN - 1);

        return offset / info->bl_len;
}

static int get_aligned_image_overhead(struct spl_load_info *info, int offset)
{
        /*
         * If it is a FS read, get the difference between the offset and
         * the first address before offset which is aligned to
         * ARCH_DMA_MINALIGN. If it is raw read return the offset within the
         * block.
         */
        if (info->filename)
                return offset & (ARCH_DMA_MINALIGN - 1);

        return offset % info->bl_len;
}

static int get_aligned_image_size(struct spl_load_info *info, int data_size,
                                  int offset)
{
        data_size = data_size + get_aligned_image_overhead(info, offset);

        if (info->filename)
                return data_size;

        return (data_size + info->bl_len - 1) / info->bl_len;
}

int spl_load_simple_fit(struct spl_image_info *spl_image,
                        struct spl_load_info *info, ulong sector, void *fit)
{
        int sectors;
        ulong size, load;
        unsigned long count;
        int node, images;
        void *load_ptr;
        int fdt_offset, fdt_len;
        int data_offset, data_size;
        int base_offset, align_len = ARCH_DMA_MINALIGN - 1;
        int src_sector;
        void *dst, *src;

        /*
         * Figure out where the external images start. This is the base for the
         * data-offset properties in each image.
         */
        size = fdt_totalsize(fit);
        size = (size + 3) & ~3;
        base_offset = (size + 3) & ~3;

        /*
         * So far we only have one block of data from the FIT. Read the entire
         * thing, including that first block, placing it so it finishes before
         * where we will load the image.
         *
         * Note that we will load the image such that its first byte will be
         * at the load address. Since that byte may be part-way through a
         * block, we may load the image up to one block before the load
         * address. So take account of that here by subtracting an addition
         * block length from the FIT start position.
         *
         * In fact the FIT has its own load address, but we assume it cannot
         * be before CONFIG_SYS_TEXT_BASE.
         */
        fit = (void *)((CONFIG_SYS_TEXT_BASE - size - info->bl_len -
                        align_len) & ~align_len);
        sectors = get_aligned_image_size(info, size, 0);
        count = info->read(info, sector, sectors, fit);
        debug("fit read sector %lx, sectors=%d, dst=%p, count=%lu\n",
              sector, sectors, fit, count);
        if (count == 0)
                return -EIO;

        /* find the firmware image to load */
        images = fdt_path_offset(fit, FIT_IMAGES_PATH);
        if (images < 0) {
                debug("%s: Cannot find /images node: %d\n", __func__, images);
                return -1;
        }
        node = fdt_first_subnode(fit, images);
        if (node < 0) {
                debug("%s: Cannot find first image node: %d\n", __func__, node);
                return -1;
        }

        /* Get its information and set up the spl_image structure */
        data_offset = fdt_getprop_u32(fit, node, "data-offset");
        data_size = fdt_getprop_u32(fit, node, "data-size");
        load = fdt_getprop_u32(fit, node, "load");
        debug("data_offset=%x, data_size=%x\n", data_offset, data_size);
        spl_image->load_addr = load;
        spl_image->entry_point = load;
        spl_image->os = IH_OS_U_BOOT;

        /*
         * Work out where to place the image. We read it so that the first
         * byte will be at 'load'. This may mean we need to load it starting
         * before then, since we can only read whole blocks.
         */
        data_offset += base_offset;
        sectors = get_aligned_image_size(info, data_size, data_offset);
        load_ptr = (void *)load;
        debug("U-Boot size %x, data %p\n", data_size, load_ptr);
        dst = load_ptr;

        /* Read the image */
        src_sector = sector + get_aligned_image_offset(info, data_offset);
        debug("Aligned image read: dst=%p, src_sector=%x, sectors=%x\n",
              dst, src_sector, sectors);
        count = info->read(info, src_sector, sectors, dst);
        if (count != sectors)
                return -EIO;
        debug("image: dst=%p, data_offset=%x, size=%x\n", dst, data_offset,
              data_size);
        src = dst + get_aligned_image_overhead(info, data_offset);

#ifdef CONFIG_SPL_FIT_IMAGE_POST_PROCESS
        board_fit_image_post_process((void **)&src, (size_t *)&data_size);
#endif

        memcpy(dst, src, data_size);

        /* Figure out which device tree the board wants to use */
        fdt_len = spl_fit_select_fdt(fit, images, &fdt_offset);
        if (fdt_len < 0)
                return fdt_len;

        /*
         * Read the device tree and place it after the image. There may be
         * some extra data before it since we can only read entire blocks.
         * And also align the destination address to ARCH_DMA_MINALIGN.
         */
        dst = (void *)((load + data_size + align_len) & ~align_len);
        fdt_offset += base_offset;
        sectors = get_aligned_image_size(info, fdt_len, fdt_offset);
        src_sector = sector + get_aligned_image_offset(info, fdt_offset);
        count = info->read(info, src_sector, sectors, dst);
        debug("Aligned fdt read: dst %p, src_sector = %x, sectors %x\n",
              dst, src_sector, sectors);
        if (count != sectors)
                return -EIO;

        /*
         * Copy the device tree so that it starts immediately after the image.
         * After this we will have the U-Boot image and its device tree ready
         * for us to start.
         */
        debug("fdt: dst=%p, data_offset=%x, size=%x\n", dst, fdt_offset,
              fdt_len);
        src = dst + get_aligned_image_overhead(info, fdt_offset);
        dst = load_ptr + data_size;

#ifdef CONFIG_SPL_FIT_IMAGE_POST_PROCESS
        board_fit_image_post_process((void **)&src, (size_t *)&fdt_len);
#endif

        memcpy(dst, src, fdt_len);

        return 0;
}