[PATCH 6/8] efi: efi: load state from devicetree

[Lucas Stach]

Am Mittwoch, den 05.07.2017, 12:56 +0200 schrieb Steffen Trumtrar:
> Signed-off-by: Steffen Trumtrar <s.trumtrar at pengutronix.de>
> ---
>  common/efi/efi.c | 56 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 56 insertions(+)
> 
> diff --git a/common/efi/efi.c b/common/efi/efi.c
> index f924385958e1..cc3051dedae9 100644
> --- a/common/efi/efi.c
> +++ b/common/efi/efi.c
> @@ -40,6 +40,8 @@
>  #include <efi.h>
>  #include <efi/efi.h>
>  #include <efi/efi-device.h>
> +#include <libfile.h>
> +#include <state.h>
>  
>  efi_runtime_services_t *RT;
>  efi_boot_services_t *BS;
> @@ -384,6 +386,60 @@ static int efi_postcore_init(void)
>  }
>  postcore_initcall(efi_postcore_init);
>  
> +static int efi_late_init(void)
> +{
> +	char *state_desc;
> +	int ret;
> +
> +	state_desc = xasprintf("/boot/EFI/barebox/state.dtb");

This might deserve a few sentences in the documentation, instead of
being buried in the code.

> +	if (state_desc) {
> +		void *fdt;
> +		size_t size;
> +		struct device_node *root = NULL;
> +		struct device_node *np = NULL;
> +		struct state *state;
> +
> +		fdt = read_file(state_desc, &size);
> +		if (!fdt) {
> +			pr_err("unable to read %s: %s\n", state_desc,
> +			       strerror(errno));
> +			return -errno;
> +		}
> +
> +		if (file_detect_type(fdt, size) != filetype_oftree) {
> +			pr_err("%s is not an oftree file.\n", state_desc);
> +			free(fdt);
> +			return -EINVAL;
> +		}
> +
> +		root = of_unflatten_dtb(fdt);
> +
> +		free(fdt);
> +
> +		if (IS_ERR(root))
> +			return PTR_ERR(root);
> +
> +		of_set_root_node(root);
> +
> +		np = of_find_node_by_alias(root, "state");
> +
> +		state = state_new_from_node(np, NULL, 0, 0, false);
> +		if (IS_ERR(state))
> +			return PTR_ERR(state);
> +
> +		ret = state_load(state);
> +		if (ret)
> +			pr_warn("Failed to load persistent state, continuing with defaults, %d\n",
> +				ret);
> +
> +		return 0;
> +	}
> +
> +	return 0;
> +}
> +late_initcall(efi_late_init);
> +
>  static int do_efiexit(int argc, char *argv[])
>  {
>  	return BS->exit(efi_parent_image, EFI_SUCCESS, 0, NULL);