// SPDX-License-Identifier: GPL-2.0+
/*
 * Copyright 2021 Google LLC
 * Written by Simon Glass <sjg@chromium.org>
 */

#define LOG_CATEGORY UCLASS_BOOTSTD

#include <common.h>
#include <blk.h>
#include <bootflow.h>
#include <bootmeth.h>
#include <bootstd.h>
#include <dm.h>
#include <env_internal.h>
#include <fs.h>
#include <malloc.h>
#include <mapmem.h>
#include <dm/uclass-internal.h>

DECLARE_GLOBAL_DATA_PTR;

int bootmeth_get_state_desc(struct udevice *dev, char *buf, int maxsize)
{
        const struct bootmeth_ops *ops = bootmeth_get_ops(dev);

        if (!ops->get_state_desc)
                return -ENOSYS;

        return ops->get_state_desc(dev, buf, maxsize);
}

int bootmeth_check(struct udevice *dev, struct bootflow_iter *iter)
{
        const struct bootmeth_ops *ops = bootmeth_get_ops(dev);

        if (!ops->check)
                return 0;

        return ops->check(dev, iter);
}

int bootmeth_read_bootflow(struct udevice *dev, struct bootflow *bflow)
{
        const struct bootmeth_ops *ops = bootmeth_get_ops(dev);

        if (!ops->read_bootflow)
                return -ENOSYS;

        return ops->read_bootflow(dev, bflow);
}

int bootmeth_set_bootflow(struct udevice *dev, struct bootflow *bflow,
                          char *buf, int size)
{
        const struct bootmeth_ops *ops = bootmeth_get_ops(dev);

        if (!ops->set_bootflow)
                return -ENOSYS;

        return ops->set_bootflow(dev, bflow, buf, size);
}

int bootmeth_boot(struct udevice *dev, struct bootflow *bflow)
{
        const struct bootmeth_ops *ops = bootmeth_get_ops(dev);

        if (!ops->boot)
                return -ENOSYS;

        return ops->boot(dev, bflow);
}

int bootmeth_read_file(struct udevice *dev, struct bootflow *bflow,
                       const char *file_path, ulong addr, ulong *sizep)
{
        const struct bootmeth_ops *ops = bootmeth_get_ops(dev);

        if (!ops->read_file)
                return -ENOSYS;

        return ops->read_file(dev, bflow, file_path, addr, sizep);
}

int bootmeth_get_bootflow(struct udevice *dev, struct bootflow *bflow)
{
        const struct bootmeth_ops *ops = bootmeth_get_ops(dev);

        if (!ops->read_bootflow)
                return -ENOSYS;
        bootflow_init(bflow, NULL, dev);

        return ops->read_bootflow(dev, bflow);
}

int bootmeth_setup_iter_order(struct bootflow_iter *iter, bool include_global)
{
        struct bootstd_priv *std;
        struct udevice **order;
        int count;
        int ret;

        ret = bootstd_get_priv(&std);
        if (ret)
                return ret;

        /* Create an array large enough */
        count = std->bootmeth_count ? std->bootmeth_count :
                uclass_id_count(UCLASS_BOOTMETH);
        if (!count)
                return log_msg_ret("count", -ENOENT);

        order = calloc(count, sizeof(struct udevice *));
        if (!order)
                return log_msg_ret("order", -ENOMEM);

        /* If we have an ordering, copy it */
        if (IS_ENABLED(CONFIG_BOOTSTD_FULL) && std->bootmeth_count) {
                int i;

                /*
                 * We don't support skipping global bootmeths. Instead, the user
                 * should omit them from the ordering
                 */
                if (!include_global)
                        return log_msg_ret("glob", -EPERM);
                memcpy(order, std->bootmeth_order,
                       count * sizeof(struct bootmeth *));

                if (IS_ENABLED(CONFIG_BOOTMETH_GLOBAL)) {
                        for (i = 0; i < count; i++) {
                                struct udevice *dev = order[i];
                                struct bootmeth_uc_plat *ucp;
                                bool is_global;

                                ucp = dev_get_uclass_plat(dev);
                                is_global = ucp->flags &
                                        BOOTMETHF_GLOBAL;
                                if (is_global) {
                                        iter->first_glob_method = i;
                                        break;
                                }
                        }
                }
        } else {
                struct udevice *dev;
                int i, upto, pass;

                /*
                 * Do two passes, one to find the normal bootmeths and another
                 * to find the global ones, if required, The global ones go at
                 * the end.
                 */
                for (pass = 0, upto = 0; pass < 1 + include_global; pass++) {
                        if (pass)
                                iter->first_glob_method = upto;
                        /*
                         * Get a list of bootmethods, in seq order (i.e. using
                         * aliases). There may be gaps so try to count up high
                         * enough to find them all.
                         */
                        for (i = 0; upto < count && i < 20 + count * 2; i++) {
                                struct bootmeth_uc_plat *ucp;
                                bool is_global;

                                ret = uclass_get_device_by_seq(UCLASS_BOOTMETH,
                                                               i, &dev);
                                if (ret)
                                        continue;
                                ucp = dev_get_uclass_plat(dev);
                                is_global =
                                        IS_ENABLED(CONFIG_BOOTMETH_GLOBAL) &&
                                        (ucp->flags & BOOTMETHF_GLOBAL);
                                if (pass ? is_global : !is_global)
                                        order[upto++] = dev;
                        }
                }
                count = upto;
        }
        if (!count)
                return log_msg_ret("count2", -ENOENT);

        if (IS_ENABLED(CONFIG_BOOTMETH_GLOBAL) && include_global &&
            iter->first_glob_method != -1 && iter->first_glob_method != count) {
                iter->cur_method = iter->first_glob_method;
                iter->doing_global = true;
        }
        iter->method_order = order;
        iter->num_methods = count;

        return 0;
}

int bootmeth_set_order(const char *order_str)
{
        struct bootstd_priv *std;
        struct udevice **order;
        int count, ret, i, len;
        const char *s, *p;

        ret = bootstd_get_priv(&std);
        if (ret)
                return ret;

        if (!order_str) {
                free(std->bootmeth_order);
                std->bootmeth_order = NULL;
                std->bootmeth_count = 0;
                return 0;
        }

        /* Create an array large enough */
        count = uclass_id_count(UCLASS_BOOTMETH);
        if (!count)
                return log_msg_ret("count", -ENOENT);

        order = calloc(count + 1, sizeof(struct udevice *));
        if (!order)
                return log_msg_ret("order", -ENOMEM);

        for (i = 0, s = order_str; *s && i < count; s = p + (*p == ' '), i++) {
                struct udevice *dev;

                p = strchrnul(s, ' ');
                len = p - s;
                ret = uclass_find_device_by_namelen(UCLASS_BOOTMETH, s, len,
                                                    &dev);
                if (ret) {
                        printf("Unknown bootmeth '%.*s'\n", len, s);
                        free(order);
                        return ret;
                }
                order[i] = dev;
        }
        order[i] = NULL;
        free(std->bootmeth_order);
        std->bootmeth_order = order;
        std->bootmeth_count = i;

        return 0;
}

/**
 * setup_fs() - Set up read to read a file
 *
 * We must redo the setup before each filesystem operation. This function
 * handles that, including setting the filesystem type if a block device is not
 * being used
 *
 * @bflow: Information about file to try
 * @desc: Block descriptor to read from (NULL if not a block device)
 * Return: 0 if OK, -ve on error
 */
static int setup_fs(struct bootflow *bflow, struct blk_desc *desc)
{
        int ret;

        if (desc) {
                ret = fs_set_blk_dev_with_part(desc, bflow->part);
                if (ret)
                        return log_msg_ret("set", ret);
        } else if (IS_ENABLED(CONFIG_BOOTSTD_FULL) && bflow->fs_type) {
                fs_set_type(bflow->fs_type);
        }

        return 0;
}

int bootmeth_try_file(struct bootflow *bflow, struct blk_desc *desc,
                      const char *prefix, const char *fname)
{
        char path[200];
        loff_t size;
        int ret, ret2;

        snprintf(path, sizeof(path), "%s%s", prefix ? prefix : "", fname);
        log_debug("trying: %s\n", path);

        free(bflow->fname);
        bflow->fname = strdup(path);
        if (!bflow->fname)
                return log_msg_ret("name", -ENOMEM);

        if (IS_ENABLED(CONFIG_BOOTSTD_FULL) && bflow->fs_type)
                fs_set_type(bflow->fs_type);

        ret = fs_size(path, &size);
        log_debug("   %s - err=%d\n", path, ret);

        /* Sadly FS closes the file after fs_size() so we must redo this */
        ret2 = setup_fs(bflow, desc);
        if (ret2)
                return log_msg_ret("fs", ret2);

        if (ret)
                return log_msg_ret("size", ret);

        bflow->size = size;
        bflow->state = BOOTFLOWST_FILE;

        return 0;
}

static int alloc_file(const char *fname, uint size, void **bufp)
{
        loff_t bytes_read;
        ulong addr;
        char *buf;
        int ret;

        buf = malloc(size + 1);
        if (!buf)
                return log_msg_ret("buf", -ENOMEM);
        addr = map_to_sysmem(buf);

        ret = fs_read(fname, addr, 0, size, &bytes_read);
        if (ret) {
                free(buf);
                return log_msg_ret("read", ret);
        }
        if (size != bytes_read)
                return log_msg_ret("bread", -EIO);
        buf[size] = '\0';

        *bufp = buf;

        return 0;
}

int bootmeth_alloc_file(struct bootflow *bflow, uint size_limit, uint align)
{
        void *buf;
        uint size;
        int ret;

        size = bflow->size;
        log_debug("   - script file size %x\n", size);
        if (size > size_limit)
                return log_msg_ret("chk", -E2BIG);

        ret = alloc_file(bflow->fname, bflow->size, &buf);
        if (ret)
                return log_msg_ret("all", ret);

        bflow->state = BOOTFLOWST_READY;
        bflow->buf = buf;

        return 0;
}

int bootmeth_alloc_other(struct bootflow *bflow, const char *fname,
                         void **bufp, uint *sizep)
{
        struct blk_desc *desc = NULL;
        char path[200];
        loff_t size;
        void *buf;
        int ret;

        snprintf(path, sizeof(path), "%s%s", bflow->subdir, fname);
        log_debug("trying: %s\n", path);

        if (bflow->blk)
                desc = dev_get_uclass_plat(bflow->blk);

        ret = setup_fs(bflow, desc);
        if (ret)
                return log_msg_ret("fs", ret);

        ret = fs_size(path, &size);
        log_debug("   %s - err=%d\n", path, ret);

        ret = setup_fs(bflow, desc);
        if (ret)
                return log_msg_ret("fs", ret);

        ret = alloc_file(path, size, &buf);
        if (ret)
                return log_msg_ret("all", ret);

        *bufp = buf;
        *sizep = size;

        return 0;
}

int bootmeth_common_read_file(struct udevice *dev, struct bootflow *bflow,
                              const char *file_path, ulong addr, ulong *sizep)
{
        struct blk_desc *desc = NULL;
        loff_t len_read;
        loff_t size;
        int ret;

        if (bflow->blk)
                desc = dev_get_uclass_plat(bflow->blk);

        ret = setup_fs(bflow, desc);
        if (ret)
                return log_msg_ret("fs", ret);

        ret = fs_size(file_path, &size);
        if (ret)
                return log_msg_ret("size", ret);
        if (size > *sizep)
                return log_msg_ret("spc", -ENOSPC);

        ret = setup_fs(bflow, desc);
        if (ret)
                return log_msg_ret("fs", ret);

        ret = fs_read(file_path, addr, 0, 0, &len_read);
        if (ret)
                return ret;
        *sizep = len_read;

        return 0;
}

#ifdef CONFIG_BOOTSTD_FULL
/**
 * on_bootmeths() - Update the bootmeth order
 *
 * This will check for a valid baudrate and only apply it if valid.
 */
static int on_bootmeths(const char *name, const char *value, enum env_op op,
                        int flags)
{
        int ret;

        switch (op) {
        case env_op_create:
        case env_op_overwrite:
                ret = bootmeth_set_order(value);
                if (ret)
                        return 1;
                return 0;
        case env_op_delete:
                bootmeth_set_order(NULL);
                fallthrough;
        default:
                return 0;
        }
}
U_BOOT_ENV_CALLBACK(bootmeths, on_bootmeths);
#endif /* CONFIG_BOOTSTD_FULL */

UCLASS_DRIVER(bootmeth) = {
        .id             = UCLASS_BOOTMETH,
        .name           = "bootmeth",
        .flags          = DM_UC_FLAG_SEQ_ALIAS,
        .per_device_plat_auto   = sizeof(struct bootmeth_uc_plat),
};