[U-Boot] [RFC v2 00/15] dm, efi: integrate efi objects into DM
Simon Glass
sjg at chromium.org
Sat Feb 9 23:00:33 UTC 2019
Hi Heinrich,
On Fri, 8 Feb 2019 at 03:36, Heinrich Schuchardt <xypron.glpk at gmx.de> wrote:
>
>
>
> On 2/8/19 9:15 AM, AKASHI Takahiro wrote:
> > # bootefi doesn't work with this patch set yet
> >
> > This patch set came from the past discussion[1] on my "removable device
> > support" patch and is intended to be an attempt to integrate efi objects
> > into u-boot's Driver Model as much seamlessly as possible.
> >
> > [1] https://lists.denx.de/pipermail/u-boot/2019-January/354010.html
> >
> > Since this patch is a prototype (or POC, Proof-Of-Concept), the aim here
> > is to discuss further about how in a better shape we will be able to
> > merge the two worlds.
> >
> > After RFC, Simon suggested that efi protocols could be also presented
> > as DM devices. This is a major change in RFC v2.
> >
> Hello Takahiro,
>
> thanks a lot for laying out your thoughts about a possible integration of
> the EFI subsystem and the driver model. Thanks also for providing a first
> implementation.
Yes indeed. It is very clever what you have been able to do Takahiro.
>
> > Basic idea is
> > * efi_root is a DM device
> > * Any efi object, refered to by efi_handle_t in UEFI world,
> > has a corresponding DM device.
>
> EFI applications and drivers will create handles having no relation to
> the U-Boot world.
I suggest that we change that, i.e. that all devices in existence have
a struct udevice. That way DM knows about everything and we don't have
the strange parallel 'EFI' world. I don't see any need for it.
>
> > - define efi_handle_t as "struct udevice *"
>
> An EFI handle does not necessarily relate to any U-Boot device. Why
> should a handle which has not backing device carry the extra fields of
> struct udevice?
Because this is the U-Boot driver model. We should not have an EFI
parallel to DM and certainly not just to save a few dozen bytes of
data space. If you were trying to save data space, you would not use
EFI :-)
>
> > - for efi_disk,
> > * add "struct efi_disk_obj" to blk_desc
>
> struct efi_disk_obj * is currently the handle of the block device. So
> you only some fields may be moved to blk_desc. But I guess I will find
> that in one of the patches.
>
> > - for the objects below, there is only one instance for each and so
> > they are currently global data:
> > efi_gop_obj,
> > efi_net_obj,
>
> efi_net_obj * is the handle of the network device. In future we should
> support multiple network devices.
>
> > simple_text_output_mode
> > - for loaded_image,
> > * link efi_loaded_image_obj to device's platdata
>
> An EFI application can create an image out of "nothing". Just create a
> handle with InstallProtocolInterface() and then call LoadImage() with a
> pointer to some place in memory.
>
> Many images loaded from the same device may be present at the same time,
> e.g. iPXE, GRUB, and Linux.
>
> >
> > * Any efi protocol has a corresponding DM device.
>
> Protocol implementations are not only provided by U-Boot but also by EFI
> applications and driver binaries. And of cause the EFI binaries will
> implement a lot of protocols completely unknown to U-Boot. So what
> should be the meaning of the above sentence in this context?
Can we instead add a uclass for each EFI protocol? Then U-Boot does
know about them.
>
> Above you suggested that struct udevice * would be used as a handle.
> So on which handle is the protocol now installed in your model?
>
> For a protocol like the device path protocol which is only a data
> structure with no related function modules I do not understand the
> benefit of creating a separate sub-device.
I think it is only a matter of convenience and to keep things regular.
>
> > - link "struct efi_handler" to device's uclass_platdata
>
> struct efi_handler is an item in the list of protocols installed on a
> handle. For some of the protocols installed by an EFI application there
> will not be any corresponding uclass.
As above, perhaps we should fix that?
>
> > - be a child of a efi object (hence DM device) in DM device hierarchy
> > so that enumerating protocols belonging to efi object is done by
> > traversing the tree.
> >
>
> Above you said a struct udevice * would be a handle. So here you imply
> that for each protocol interface you will create an extra handle. That
> does not fit the EFI model.
>
> > * Any efi object which has a backing DM device should be created
> > when that DM device is detected (and probed).
>
> Detected or probed? This is not the same.
>
> > * For efi_disk (or any object with EFI_BLOCK_IO_PROTOCOL),
> > - add UCLASS_PARTITION
> > - put partitions under a raw block device
> > - partitions as well as raw devices can be efi_disk
>
> Agreed.
>
> >
> > With those extensive changes, there still exists plenty of
> > "wrapper" code. Do you have any idea to reduce it?
> >
>
> The concept presented does not cover:
>
> - device, drivers, protocols created by EFI applications and
> driver binaries
Can we create uclasses for each 'protocol'? Is there any reason why we cannot?
> - non-DM drivers and devices in U-Boot
This doesn't really matter as they will be gone soon. At the risk of
repeating myself, EFI support should never have supported non-DM in
the first place. It was not the right decision, in my view.
>
> It creates extra handles per installed protocol interface which should
> not exist in the EFI world.
>
> So some rework of the concept is needed.
>
> I suggest to start smaller:
>
> - convert partitions to the DM model.
This is in later patches from what I can tell.
> - provide a pointer serving as EFI handle in struct udevice
I actually feel that the approach here, while admittedly bold, seems
to be a good step forward.
Regards,
Simon
>
> Best regards
>
> Heinrich
>
> >
> > ***** Example operation ******
> > (Two scsi disks, one with no partition, one with two partitions)
> >
> > => efi dev
> > EFI: Initializing UCLASS_EFI_DRIVER
> > Device Device Path
> > ================ ====================
> > 000000007eef9470 /VenHw(e61d73b9-a384-4acc-aeab-82e828f3628b)
> > => scsi rescan
> >
> > Reset SCSI
> > scanning bus for devices...
> > Target spinup took 0 ms.
> > Target spinup took 0 ms.
> > SATA link 2 timeout.
> > SATA link 3 timeout.
> > SATA link 4 timeout.
> > SATA link 5 timeout.
> > AHCI 0001.0000 32 slots 6 ports 1.5 Gbps 0x3f impl SATA mode
> > flags: 64bit ncq only
> > Device 0: (0:0) Vendor: ATA Prod.: QEMU HARDDISK Rev: 2.5+
> > Type: Hard Disk
> > Capacity: 16.0 MB = 0.0 GB (32768 x 512)
> > Device 0: (1:0) Vendor: ATA Prod.: QEMU HARDDISK Rev: 2.5+
> > Type: Hard Disk
> > Capacity: 256.0 MB = 0.2 GB (524288 x 512)
> > => efi dev
> > Device Device Path
> > ================ ====================
> > 000000007eef9470 /VenHw(e61d73b9-a384-4acc-aeab-82e828f3628b)
> > 000000007ef01c90 /VenHw(e61d73b9-a384-4acc-aeab-82e828f3628b)/Scsi(0,0)
> > 000000007ef04910 /VenHw(e61d73b9-a384-4acc-aeab-82e828f3628b)/Scsi(1,0)
> > 000000007ef04ee0 /VenHw(e61d73b9-a384-4acc-aeab-82e828f3628b)/Scsi(1,0)/HD(335544330,MBR,0x086246ba,0x17ff4f1a0,0x7eee3770)
> > 000000007ef055a0 /VenHw(e61d73b9-a384-4acc-aeab-82e828f3628b)/Scsi(1,0)/HD(335544330,MBR,0x086246ba,0x17ff4f1a0,0x7eee3770)
> > => dm tree
> > Class index Probed Driver Name
> > -----------------------------------------------------------
> > root 0 [ + ] root_driver root_driver
> > simple_bus 0 [ ] generic_simple_bus |-- platform at c000000
> > virtio 0 [ + ] virtio-mmio |-- virtio_mmio at a000000
> >
> > [snip]
> >
> > pci 0 [ + ] pci_generic_ecam |-- pcie at 10000000
> > pci_generi 0 [ ] pci_generic_drv | |-- pci_0:0.0
> > virtio 32 [ ] virtio-pci.l | |-- virtio-pci.l#0
> > ahci 0 [ + ] ahci_pci | `-- ahci_pci
> > scsi 0 [ + ] ahci_scsi | `-- ahci_scsi
> > blk 0 [ + ] scsi_blk | |-- ahci_scsi.id0lun0
> > efi_protoc 8 [ + ] efi_disk | | |-- BLOCK_IO
> > efi_protoc 9 [ + ] efi_device_path | | `-- Scsi(0,0)
> > blk 1 [ + ] scsi_blk | `-- ahci_scsi.id1lun0
> > efi_protoc 10 [ + ] efi_disk | |-- BLOCK_IO
> > efi_protoc 11 [ + ] efi_device_path | |-- Scsi(1,0)
> > partition 0 [ + ] blk_partition | |-- ahci_scsi.id1lun0:1
> > efi_protoc 12 [ + ] efi_disk | | |-- BLOCK_IO
> > efi_protoc 13 [ + ] efi_device_path | | |-- HD(335544330,MBR,0x086246ba,0x17ff4f1a0,0x7eee3770)
> > efi_protoc 14 [ + ] efi_simple_file_syst | | `-- SIMPLE_FILE_SYSTEM
> > partition 1 [ + ] blk_partition | `-- ahci_scsi.id1lun0:2
> > efi_protoc 15 [ + ] efi_disk | |-- BLOCK_IO
> > efi_protoc 16 [ + ] efi_device_path | |-- HD(335544330,MBR,0x086246ba,0x17ff4f1a0,0x7eee3770)
> > efi_protoc 17 [ + ] efi_simple_file_syst | `-- SIMPLE_FILE_SYSTEM
> > rtc 0 [ ] rtc-pl031 |-- pl031 at 9010000
> > serial 0 [ ] serial_pl01x |-- pl011 at 9050000
> > serial 1 [ + ] serial_pl01x |-- pl011 at 9000000
> > efi_protoc 0 [ + ] efi_simple_text_outp | |-- SIMPLE_TEXT_OUTPUT
> > efi_protoc 1 [ + ] efi_simple_text_inpu | |-- SIMPLE_TEXT_INPUT
> > efi_protoc 2 [ + ] efi_simple_text_inpu | `-- SIMPLE_TEXT_INPUT_EX
> > mtd 0 [ + ] cfi_flash |-- flash at 0
> > firmware 0 [ + ] psci |-- psci
> > sysreset 0 [ ] psci-sysreset | `-- psci-sysreset
> > efi 0 [ + ] efi_root `-- UEFI sub system
> > efi_protoc 3 [ + ] efi_device_path |-- VenHw(e61d73b9-a384-4acc-aeab-82e828f3628b)
> > efi_protoc 4 [ + ] efi_device_path_to_t |-- DEVICE_PATH_TO_TEXT
> > efi_protoc 5 [ + ] efi_device_path_util |-- DEVICE_PATH_UTILITIES
> > efi_protoc 6 [ + ] efi_unicode_collatio |-- en
> > efi_driver 0 [ + ] EFI block driver `-- EFI block driver
> > efi_protoc 7 [ + ] efi_driver_binding `-- DRIVER_BINDING
> >
> >
> >
> > Thanks,
> > -Takahiro Akashi
> >
> > AKASHI Takahiro (15):
> > efi_loader: efi objects and protocols as DM devices
> > efi_loader: boottime: convert efi_loaded_image_obj to DM
> > efi_loader: image_loader: aligned with DM
> > efi_driver: rename UCLASS_EFI to UCLASS_EFI_DRIVER
> > efi_loader: convert efi_root_node to DM
> > efi_loader: device path: convert efi_device_path to DM
> > efi_loader: unicode_collation: converted to DM
> > efi_loader: console: convert efi console input/output to DM
> > efi_loader: net: convert efi_net_obj to DM
> > efi_loader: gop: convert efi_gop_obj to DM
> > dm: blk: add UCLASS_PARTITION
> > efi_loader: disk: convert efi_disk_obj to DM
> > drivers: align block device drivers with DM-efi integration
> > efi_driver: converted to DM
> > cmd: efidebug: aligned with DM-efi integration
> >
> > cmd/bootefi.c | 61 +--
> > cmd/efidebug.c | 5 +-
> > common/usb_storage.c | 27 +-
> > drivers/block/blk-uclass.c | 61 +++
> > drivers/scsi/scsi.c | 22 +
> > drivers/serial/serial-uclass.c | 6 +
> > drivers/video/video-uclass.c | 9 +
> > include/blk.h | 24 +
> > include/dm/device.h | 3 +
> > include/dm/uclass-id.h | 6 +-
> > include/efi.h | 4 +-
> > include/efi_loader.h | 50 +-
> > lib/efi_driver/efi_block_device.c | 36 +-
> > lib/efi_driver/efi_uclass.c | 37 +-
> > lib/efi_loader/efi_boottime.c | 605 ++++++++++++++-------
> > lib/efi_loader/efi_console.c | 64 ++-
> > lib/efi_loader/efi_device_path.c | 136 +++--
> > lib/efi_loader/efi_device_path_to_text.c | 55 ++
> > lib/efi_loader/efi_device_path_utilities.c | 14 +
> > lib/efi_loader/efi_disk.c | 216 +++++---
> > lib/efi_loader/efi_file.c | 14 +
> > lib/efi_loader/efi_gop.c | 28 +-
> > lib/efi_loader/efi_image_loader.c | 61 ++-
> > lib/efi_loader/efi_net.c | 50 +-
> > lib/efi_loader/efi_root_node.c | 14 +-
> > lib/efi_loader/efi_setup.c | 60 +-
> > lib/efi_loader/efi_unicode_collation.c | 19 +
> > net/eth-uclass.c | 5 +
> > 28 files changed, 1226 insertions(+), 466 deletions(-)
> >
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