[U-Boot] [PATCH v3 3/8] cmd: efishell: add drivers command

[AKASHI Takahiro <takahiro.akashi@linaro.org>]

On Thu, Dec 20, 2018 at 08:51:34AM +0100, Heinrich Schuchardt wrote:
> On 12/18/18 6:05 AM, AKASHI Takahiro wrote:
> > "drivers" command prints all the uefi drivers on the system.
> > => efi drivers
> > Driver Name     Image Path
> > ============================================
> > (unknown)       <NULL>+(not found)
> >     guid: 18a031ab-b443-4d1a-a5c0-0c09261e9f71
> > 
> > Currently, no useful information can be printed.
> 
> Why? We have lib/efi_driver/efi_block_device.c. So you should be able to
> test the output.

There are a couple of reasons that I think there are no useful
information:
1. EFI driver doesn't have any printable name.
   A corresponding u-boot driver, efi_block in efi_block_device.c,
   has a name, but there is not direct link between efi driver
   and this u-boot driver. So it's not easy to find a name for efi driver.
2. I will fix this by adding a "name" field to
   efi_driver_binding_extended_protocol, but if even so, we can only
   say "EFI block driver." We have no chance to know about controller
   -specific, say USB, SCSI or anything, information.

3. More importantly, efi block devices can be defined in two ways,
   via efi_uclass/efi_block_device and efi_disk. The latter supports
   BLOCK_IO_PROTOCOL binding having any associated driver/controller.
   It seems to me that it's quite confusion.

Thanks,
-Takahiro Akashi



> Best regards
> 
> Heirnich
> 
> > 
> > Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
> > ---
> >  cmd/efishell.c | 95 +++++++++++++++++++++++++++++++++++++++++++++++++-
> >  1 file changed, 94 insertions(+), 1 deletion(-)
> > 
> > diff --git a/cmd/efishell.c b/cmd/efishell.c
> > index 929b6343b1b2..ed8de9e0355d 100644
> > --- a/cmd/efishell.c
> > +++ b/cmd/efishell.c
> > @@ -343,6 +343,95 @@ static int do_efi_show_devices(int argc, char * const argv[])
> >  	return CMD_RET_SUCCESS;
> >  }
> >  
> > +static int efi_get_driver_handle_info(efi_handle_t handle, u16 **name,
> > +				      u16 **devname, u16 **filename)
> > +{
> > +	struct efi_driver_binding_protocol *binding;
> > +	struct efi_loaded_image *image;
> > +	efi_status_t ret;
> > +
> > +	ret = bs->open_protocol(handle, &efi_guid_driver_binding_protocol,
> > +				(void **)&binding, NULL, NULL,
> > +				EFI_OPEN_PROTOCOL_GET_PROTOCOL);
> > +	if (ret != EFI_SUCCESS)
> > +		return -1;
> > +
> > +	ret = bs->open_protocol(binding->image_handle, &efi_guid_loaded_image,
> > +				(void **)&image, NULL /* FIXME */, NULL,
> > +				EFI_OPEN_PROTOCOL_GET_PROTOCOL);
> > +	if (ret != EFI_SUCCESS)
> > +		goto e_out;
> > +
> > +	/*
> > +	 * TODO:
> > +	 * handle image->device_handle,
> > +	 * use append_device_path()
> > +	 */
> > +	*devname = NULL;
> > +	*filename = efi_dp_str(image->file_path);
> > +
> > +	return 0;
> > +
> > +e_out:
> > +	*devname = NULL;
> > +	*filename = NULL;
> > +
> > +	return 0;
> > +}
> > +
> > +static int do_efi_show_drivers(int argc, char * const argv[])
> > +{
> > +	efi_handle_t *handles = NULL, *handle;
> > +	efi_uintn_t size = 0;
> > +	u16 *drvname, *devname, *filename;
> > +	efi_status_t ret;
> > +	int i;
> > +
> > +	ret = bs->locate_handle(BY_PROTOCOL, &efi_guid_driver_binding_protocol,
> > +				NULL, &size, NULL);
> > +	if (ret == EFI_BUFFER_TOO_SMALL) {
> > +		handles = calloc(1, size);
> > +		if (!handles)
> > +			return CMD_RET_FAILURE;
> > +
> > +		ret = bs->locate_handle(BY_PROTOCOL,
> > +					&efi_guid_driver_binding_protocol,
> > +					NULL, &size, handles);
> > +	}
> > +	if (ret != EFI_SUCCESS) {
> > +		free(handles);
> > +		return CMD_RET_FAILURE;
> > +	}
> > +
> > +	printf("Driver Name     Image Path\n");
> > +	printf("============================================\n");
> > +	handle = handles;
> > +	for (i = 0; i < size / sizeof(*handle); i++) {
> > +		if (!efi_get_driver_handle_info(*handle, &drvname, &devname,
> > +						&filename)) {
> > +			printf("%-16s%ls+%ls\n",
> > +			       "(unknown)", devname, filename);
> > +			efi_free_pool(devname);
> > +			efi_free_pool(filename);
> > +
> > +			/* TODO: no other info */
> > +			struct efi_object *efiobj;
> > +			struct list_head *lhandle;
> > +			struct efi_handler *protocol;
> > +
> > +			efiobj = efi_search_obj(*handle);
> > +			list_for_each(lhandle, &efiobj->protocols) {
> > +				protocol = list_entry(lhandle,
> > +						      struct efi_handler, link);
> > +				printf("    guid: %pUl\n", protocol->guid);
> > +			}
> > +		}
> > +		handle++;
> > +	}
> > +
> > +	return CMD_RET_SUCCESS;
> > +}
> > +
> >  static int do_efi_boot_add(int argc, char * const argv[])
> >  {
> >  	int id;
> > @@ -726,6 +815,8 @@ static int do_efishell(cmd_tbl_t *cmdtp, int flag,
> >  		return do_efi_set_var(argc, argv);
> >  	else if (!strcmp(command, "devices"))
> >  		return do_efi_show_devices(argc, argv);
> > +	else if (!strcmp(command, "drivers"))
> > +		return do_efi_show_drivers(argc, argv);
> >  	else
> >  		return CMD_RET_USAGE;
> >  }
> > @@ -749,7 +840,9 @@ static char efishell_help_text[] =
> >  	"  - set/delete uefi variable's value\n"
> >  	"    <value> may be \"=\"...\"\", \"=0x...\" (set) or \"=\" (delete)\n"
> >  	"efishell devices\n"
> > -	"  - show uefi devices\n";
> > +	"  - show uefi devices\n"
> > +	"efishell drivers\n"
> > +	"  - show uefi drivers\n";
> >  #endif
> >  
> >  U_BOOT_CMD(
> > 
>