[PATCH 4/4] efi: add helper functions to insert pmem node for DT fixup

[Heinrich Schuchardt]

On 10/25/24 13:14, Sughosh Ganu wrote:
> The EFI HTTP boot puts the iso installer image at some location in
> memory which needs to be reserved in the devicetree as persistent
> memory (pmem). Add helper functions which add this pmem node when the
> EFI_DT_FIXUP protocol's fixup callback is invoked.
>
> Signed-off-by: Sughosh Ganu <sughosh.ganu at linaro.org>
> ---
>   boot/image-fdt.c             |  9 +++++++++
>   include/efi_loader.h         | 17 +++++++++++++++++
>   lib/efi_loader/efi_bootmgr.c | 21 +++++++++++++++++++++
>   lib/efi_loader/efi_helper.c  | 12 ++++++++++++
>   4 files changed, 59 insertions(+)
>
> diff --git a/boot/image-fdt.c b/boot/image-fdt.c
> index 8eda521693..b39e81ad30 100644
> --- a/boot/image-fdt.c
> +++ b/boot/image-fdt.c
> @@ -11,6 +11,7 @@
>   #include <command.h>
>   #include <fdt_support.h>
>   #include <fdtdec.h>
> +#include <efi_loader.h>
>   #include <env.h>
>   #include <errno.h>
>   #include <image.h>
> @@ -648,6 +649,14 @@ int image_setup_libfdt(struct bootm_headers *images, void *blob, bool lmb)
>   	if (!ft_verify_fdt(blob))
>   		goto err;
>
> +	if (CONFIG_IS_ENABLED(EFI_HTTP_BOOT)) {
> +		fdt_ret = fdt_efi_pmem_setup(blob);

Having EFI_HTTP_BOOT is not the only way to load an image to memory. You
could have downloaded it via TFTP or taken it from a block device. So
this config check looks wrong. Why don't you check for the presence of
memory block devices here?

You need to check if the board is using ACPI, if yes, provide the ACPI
table.

Best regards

Heinrich

> +		if (fdt_ret) {
> +			printf("ERROR: HTTP boot pmem fixup failed\n");
> +			goto err;
> +		}
> +	}
> +
>   	/* after here we are using a livetree */
>   	if (!of_live_active() && CONFIG_IS_ENABLED(EVENT)) {
>   		struct event_ft_fixup fixup;
> diff --git a/include/efi_loader.h b/include/efi_loader.h
> index d450e304c6..031de18746 100644
> --- a/include/efi_loader.h
> +++ b/include/efi_loader.h
> @@ -748,6 +748,15 @@ bool efi_varname_is_load_option(u16 *var_name16, int *index);
>   efi_status_t efi_next_variable_name(efi_uintn_t *size, u16 **buf,
>   				    efi_guid_t *guid);
>
> +/**
> + * fdt_efi_pmem_setup() - Setup the pmem node in the devicetree
> + *
> + * @fdt:	Pointer to the devicetree
> + *
> + * Return:	0 on success, negative on failure
> + */
> +int fdt_efi_pmem_setup(void *fdt);
> +
>   /**
>    * efi_size_in_pages() - convert size in bytes to size in pages
>    *
> @@ -964,6 +973,14 @@ efi_status_t efi_set_load_options(efi_handle_t handle,
>   				  void *load_options);
>   efi_status_t efi_bootmgr_load(efi_handle_t *handle, void **load_options);
>
> +/**
> + * efi_bootmgr_pmem_setup() - Put a pmem node for UEFI HTTP installers
> + *
> + * @fdt:	Pointer to the DT blob
> + * Return:	status code
> + */
> +efi_status_t efi_bootmgr_pmem_setup(void *fdt);
> +
>   /**
>    * struct efi_image_regions - A list of memory regions
>    *
> diff --git a/lib/efi_loader/efi_bootmgr.c b/lib/efi_loader/efi_bootmgr.c
> index 16f75555f6..1d9246be61 100644
> --- a/lib/efi_loader/efi_bootmgr.c
> +++ b/lib/efi_loader/efi_bootmgr.c
> @@ -41,6 +41,8 @@ struct uridp_context {
>   	efi_handle_t mem_handle;
>   };
>
> +static struct uridp_context *uctx;
> +
>   const efi_guid_t efi_guid_bootmenu_auto_generated =
>   		EFICONFIG_AUTO_GENERATED_ENTRY_GUID;
>
> @@ -423,6 +425,7 @@ efi_status_t efi_bootmgr_release_uridp(struct uridp_context *ctx)
>
>   	efi_free_pool(ctx->loaded_dp);
>   	free(ctx);
> +	uctx = NULL;
>
>   	return ret == EFI_SUCCESS ? ret2 : ret;
>   }
> @@ -443,6 +446,23 @@ static void EFIAPI efi_bootmgr_http_return(struct efi_event *event,
>   	EFI_EXIT(ret);
>   }
>
> +/**
> + * efi_bootmgr_pmem_setup() - Put a pmem node for UEFI HTTP installers
> + *
> + * @fdt:	Pointer to the DT blob
> + * Return:	status code
> + */
> +efi_status_t efi_bootmgr_pmem_setup(void *fdt)
> +{
> +	if (!uctx) {
> +		log_warning("No EFI HTTP boot context found\n");
> +		return EFI_SUCCESS;
> +	}
> +
> +	return !fdt_fixup_pmem_region(fdt, uctx->image_addr, uctx->image_size) ?
> +		EFI_SUCCESS : EFI_INVALID_PARAMETER;
> +}
> +
>   /**
>    * try_load_from_uri_path() - Handle the URI device path
>    *
> @@ -472,6 +492,7 @@ static efi_status_t try_load_from_uri_path(struct efi_device_path_uri *uridp,
>   	if (!ctx)
>   		return EFI_OUT_OF_RESOURCES;
>
> +	uctx = ctx;
>   	s = env_get("loadaddr");
>   	if (!s) {
>   		log_err("Error: loadaddr is not set\n");
> diff --git a/lib/efi_loader/efi_helper.c b/lib/efi_loader/efi_helper.c
> index 00167bd2a1..33cd8b9a50 100644
> --- a/lib/efi_loader/efi_helper.c
> +++ b/lib/efi_loader/efi_helper.c
> @@ -242,6 +242,18 @@ int efi_unlink_dev(efi_handle_t handle)
>   	return 0;
>   }
>
> +/**
> + * fdt_efi_pmem_setup() - Setup the pmem node in the devicetree
> + *
> + * @fdt:	Pointer to the devicetree
> + *
> + * Return:	0 on success, negative on failure
> + */
> +int fdt_efi_pmem_setup(void *fdt)
> +{
> +	return efi_bootmgr_pmem_setup(fdt) == EFI_SUCCESS ? 0 : -1;
> +}
> +
>   static int u16_tohex(u16 c)
>   {
>   	if (c >= '0' && c <= '9')