[PATCH 02/12] fdt_support: add fdt_copy_fixed_partitions function

[Simon Glass]

Hi Patrick,

On Thu, 8 Jun 2023 at 16:16, Patrick Delaunay
<patrick.delaunay at foss.st.com> wrote:
>
> Add a new function fdt_copy_fixed_partitions to copy the fixed
> partition nodes from U-Boot device tree to Linux kernel
> device tree and to dynamically configure the MTD partitions.
>
> This function fdt_copy_fixed_partitions is only based on device tree
> with livetree compatible function and replace the function
> fdt_fixup_mtdparts based on mtdparts variable.
>
> Signed-off-by: Patrick Delaunay <patrick.delaunay at foss.st.com>
> ---
>
>  common/fdt_support.c  | 73 +++++++++++++++++++++++++++++++++++++++++++
>  include/fdt_support.h |  8 +++++
>  2 files changed, 81 insertions(+)
>
> diff --git a/common/fdt_support.c b/common/fdt_support.c
> index ffc59fd8b36a..5e49078f8c35 100644
> --- a/common/fdt_support.c
> +++ b/common/fdt_support.c
> @@ -1051,6 +1051,79 @@ void fdt_fixup_mtdparts(void *blob, const struct node_info *node_info,
>  }
>  #endif
>
> +int fdt_copy_fixed_partitions(void *blob)
> +{
> +       ofnode node, subnode;
> +       int off, suboff, res;
> +       char path[256];
> +       int address_cells, size_cells;
> +       u8 i, j, child_count;
> +
> +       node = ofnode_by_compatible(ofnode_null(), "fixed-partitions");
> +       while (ofnode_valid(node)) {
> +               /* copy the U-Boot fixed partition */
> +               address_cells = ofnode_read_simple_addr_cells(node);
> +               size_cells = ofnode_read_simple_size_cells(node);
> +
> +               res = ofnode_get_path(ofnode_get_parent(node), path, sizeof(path));
> +               if (res)
> +                       return res;
> +
> +               off = fdt_path_offset(blob, path);
> +               if (off < 0)
> +                       return -ENODEV;

It should be possible to use livetree to write to the blob. E.g.:

oftree tree = oftree_from_fdt(blob);
ofnode node = oftree_path(tree, "/...");

That would be more future-proof than using this API. I'd like to move
DT fixup to the ofnode API eventually.

> +
> +               off = fdt_find_or_add_subnode(blob, off, "partitions");
> +               res = fdt_setprop_string(blob, off, "compatible", "fixed-partitions");
> +               if (res)
> +                       return res;
> +
> +               res = fdt_setprop_u32(blob, off, "#address-cells", address_cells);
> +               if (res)
> +                       return res;
> +
> +               res = fdt_setprop_u32(blob, off, "#size-cells", size_cells);
> +               if (res)
> +                       return res;
> +
> +               /*
> +                * parse partition in reverse order as fdt_find_or_add_subnode() only
> +                * insert the new node after the parent's properties
> +                */
> +               child_count = ofnode_get_child_count(node);
> +               for (i = child_count; i > 0 ; i--) {
> +                       subnode = ofnode_first_subnode(node);
> +                       if (!ofnode_valid(subnode))
> +                               break;
> +
> +                       for (j = 0; (j < i - 1); j++)
> +                               subnode = ofnode_next_subnode(subnode);
> +
> +                       if (!ofnode_valid(subnode))
> +                               break;
> +
> +                       const u32 *reg;
> +                       int len;
> +
> +                       suboff = fdt_find_or_add_subnode(blob, off, ofnode_get_name(subnode));
> +                       res = fdt_setprop_string(blob, suboff, "label",
> +                                                ofnode_read_string(subnode, "label"));
> +                       if (res)
> +                               return res;
> +
> +                       reg = ofnode_get_property(subnode, "reg", &len);
> +                       res = fdt_setprop(blob, suboff, "reg", reg, len);
> +                       if (res)
> +                               return res;
> +               }
> +
> +               /* go to next fixed-partitions node */
> +               node = ofnode_by_compatible(node, "fixed-partitions");
> +       }
> +
> +       return 0;
> +}
> +
>  void fdt_del_node_and_alias(void *blob, const char *alias)
>  {
>         int off = fdt_path_offset(blob, alias);
> diff --git a/include/fdt_support.h b/include/fdt_support.h
> index eeb83e6251d3..2cd836689821 100644
> --- a/include/fdt_support.h
> +++ b/include/fdt_support.h
> @@ -256,6 +256,14 @@ static inline void fdt_fixup_mtdparts(void *fdt,
>  }
>  #endif
>
> +/**
> + * copy the fixed-partition nodes from U-Boot device tree to external blob
> + *
> + * @param blob         FDT blob to update
> + * Return: 0 if ok, or non-zero on error
> + */
> +int fdt_copy_fixed_partitions(void *blob);
> +
>  void fdt_del_node_and_alias(void *blob, const char *alias);
>
>  /**
> --
> 2.25.1
>

Regards,
Simon