On 11/18/21 1:12 PM, Rob Herring wrote:
> Use of the of_scan_flat_dt() function predates libfdt and is discouraged
> as libfdt provides a nicer set of APIs. Rework early_init_dt_scan_root()
> to be called directly and use libfdt.
>
> Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
> Cc: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx>
> Cc: Paul Mackerras <paulus@xxxxxxxxx>
> Cc: Frank Rowand <frowand.list@xxxxxxxxx>
> Cc: linuxppc-dev@xxxxxxxxxxxxxxxx
> Signed-off-by: Rob Herring <robh@xxxxxxxxxx>
> ---
> arch/powerpc/kernel/prom.c | 4 ++--
> drivers/of/fdt.c | 14 +++++++-------
> include/linux/of_fdt.h | 3 +--
> 3 files changed, 10 insertions(+), 11 deletions(-)
>
> diff --git a/arch/powerpc/kernel/prom.c b/arch/powerpc/kernel/prom.c
> index c6c398ccd98a..6e1a106f02eb 100644
> --- a/arch/powerpc/kernel/prom.c
> +++ b/arch/powerpc/kernel/prom.c
> @@ -748,7 +748,7 @@ void __init early_init_devtree(void *params)
> of_scan_flat_dt(early_init_dt_scan_chosen_ppc, boot_command_line);
>
> /* Scan memory nodes and rebuild MEMBLOCKs */
> - of_scan_flat_dt(early_init_dt_scan_root, NULL);
> + early_init_dt_scan_root();
> of_scan_flat_dt(early_init_dt_scan_memory_ppc, NULL);
>
> parse_early_param();
> @@ -857,7 +857,7 @@ void __init early_get_first_memblock_info(void *params, phys_addr_t *size)
> * mess the memblock.
> */
> add_mem_to_memblock = 0;
> - of_scan_flat_dt(early_init_dt_scan_root, NULL);
> + early_init_dt_scan_root();
> of_scan_flat_dt(early_init_dt_scan_memory_ppc, NULL);
> add_mem_to_memblock = 1;
>
> diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c
> index 1f1705f76263..5e216555fe4f 100644
> --- a/drivers/of/fdt.c
> +++ b/drivers/of/fdt.c
> @@ -1042,13 +1042,14 @@ int __init early_init_dt_scan_chosen_stdout(void)
> /*
> * early_init_dt_scan_root - fetch the top level address and size cells
> */
> -int __init early_init_dt_scan_root(unsigned long node, const char *uname,
> - int depth, void *data)
> +int __init early_init_dt_scan_root(void)
> {
> const __be32 *prop;
> + const void *fdt = initial_boot_params;
> + int node = fdt_path_offset(fdt, "/");
>
> - if (depth != 0)
> - return 0;
> + if (node < 0)
> + return -ENODEV;
>
> dt_root_size_cells = OF_ROOT_NODE_SIZE_CELLS_DEFAULT;
> dt_root_addr_cells = OF_ROOT_NODE_ADDR_CELLS_DEFAULT;
> @@ -1063,8 +1064,7 @@ int __init early_init_dt_scan_root(unsigned long node, const char *uname,
> dt_root_addr_cells = be32_to_cpup(prop);
> pr_debug("dt_root_addr_cells = %x\n", dt_root_addr_cells);
>
> - /* break now */
> - return 1;
> + return 0;
> }
>
> u64 __init dt_mem_next_cell(int s, const __be32 **cellp)
> @@ -1263,7 +1263,7 @@ void __init early_init_dt_scan_nodes(void)
> int rc;
>
> /* Initialize {size,address}-cells info */
> - of_scan_flat_dt(early_init_dt_scan_root, NULL);
> + early_init_dt_scan_root();
>
> /* Retrieve various information from the /chosen node */
> rc = early_init_dt_scan_chosen(boot_command_line);
> diff --git a/include/linux/of_fdt.h b/include/linux/of_fdt.h
> index 654722235df6..df3d31926c3c 100644
> --- a/include/linux/of_fdt.h
> +++ b/include/linux/of_fdt.h
> @@ -68,8 +68,7 @@ extern void early_init_dt_add_memory_arch(u64 base, u64 size);
> extern u64 dt_mem_next_cell(int s, const __be32 **cellp);
>
> /* Early flat tree scan hooks */
> -extern int early_init_dt_scan_root(unsigned long node, const char *uname,
> - int depth, void *data);
> +extern int early_init_dt_scan_root(void);
>
> extern bool early_init_dt_scan(void *params);
> extern bool early_init_dt_verify(void *params);
>
Reviewed-by: Frank Rowand <frank.rowand@xxxxxxxx>
