u-boot.git/drivers/virtio, branch v2024.01

virtio: rng: gracefully handle 0 byte returns

2023-11-17T16:58:26+00:00

According to the virtio v1.x "entropy device" specification, a virtio-rng
device is supposed to always return at least one byte of entropy.
However the virtio v0.9 spec does not mention such a requirement.

The Arm Fixed Virtual Platform (FVP) implementation of virtio-rng always
returns 8 bytes less of entropy than requested. If 8 bytes or less are
requested, it will return 0 bytes.
This behaviour makes U-Boot's virtio_rng_read() implementation go into an
endless loop, hanging the system.

Work around this problem by always requesting 8 bytes more than needed,
but only if a previous call to virtqueue_get_buf() returned 0 bytes.

This should never trigger on a v1.x spec compliant implementation, but
fixes the hang on the Arm FVP.

Signed-off-by: Andre Przywara 
Reported-by: Peter Hoyes

bootstd: Rename bootdev_setup_sibling_blk()

2023-08-09T15:31:11+00:00

This name is a little confusing since it suggests that it sets up the
sibling block device. In fact it sets up a bootdev for it. Rename the
function to make this clearer.

Signed-off-by: Simon Glass 
Reviewed-by: Bin Meng 
Reviewed-by: Mattijs Korpershoek

virtio: provide driver name in debug message

2023-08-03T19:30:53+00:00

If a driver cannot be bound, provide the driver name in the debug
message. Now the debug message may look like this:

    (virtio-pci.l#0): virtio-rng driver not configured

Signed-off-by: Heinrich Schuchardt 
Reviewed-by: Simon Glass

virtio: Ensure PCI is set up first

2023-04-26T12:43:04+00:00

Sometimes virtio may rely on PCI, or at least that is what the
distro_bootcmd script suggests. Add this in.

Signed-off-by: Simon Glass

virtio: Use bounce buffers when VIRTIO_F_IOMMU_PLATFORM is set

2023-04-25T15:53:15+00:00

Devices advertising the VIRTIO_F_IOMMU_PLATFORM feature require
platform-specific handling to configure their DMA transactions.

When handling virtio descriptors for such a device, use bounce
buffers to ensure that the underlying buffers are always aligned
to and padded to PAGE_SIZE in preparation for platform specific
handling at page granularity.

Signed-off-by: Will Deacon 
[ Paul: pick from the Android tree. Rebase to the upstream ]
Signed-off-by: Ying-Chun Liu (PaulLiu) 
Cc: Bin Meng 
Link: https://android.googlesource.com/platform/external/u-boot/+/1eff171e613ee67dca71dbe97be7282e2db17011
Reviewed-by: Simon Glass

virtio: Allocate bounce buffers for devices with VIRTIO_F_IOMMU_PLATFORM

2023-04-25T15:53:15+00:00

In preparation for bouncing virtio data for devices advertising the
VIRTIO_F_IOMMU_PLATFORM feature, allocate an array of bounce buffer
structures in the vring, one per descriptor.

Signed-off-by: Will Deacon 
[ Paul: pick from the Android tree. Rebase to the upstream ]
Signed-off-by: Ying-Chun Liu (PaulLiu) 
Cc: Bin Meng 
Link: https://android.googlesource.com/platform/external/u-boot/+/3e052749e7c50c4c1a6014e645ae3b9be3710c07
Reviewed-by: Simon Glass

virtio: Add helper functions to attach/detach vring descriptors

2023-04-25T15:53:15+00:00

Move the attach and detach logic for manipulating vring descriptors
out into their own functions so that we can later extend these to
bounce the data for devices with VIRTIO_F_IOMMU_PLATFORM set.

Signed-off-by: Will Deacon 
[ Paul: pick from the Android tree. Rebase to the upstream ]
Signed-off-by: Ying-Chun Liu (PaulLiu) 
Cc: Bin Meng 
Link: https://android.googlesource.com/platform/external/u-boot/+/f73258a4bfe968c5f935db45f2ec5cc0104ee796
Reviewed-by: Simon Glass

virtio: Allocate virtqueue in page-size units

2023-04-25T15:53:15+00:00

In preparation for explicit bouncing of virtqueue pages for devices
advertising the VIRTIO_F_IOMMU_PLATFORM feature, introduce a couple
of wrappers around virtqueue allocation and freeing operations,
ensuring that buffers are handled in terms of page-size units.

Signed-off-by: Will Deacon 
[ Paul: pick from the Android tree. Rebase to the upstream ]
Signed-off-by: Ying-Chun Liu (PaulLiu) 
Cc: Bin Meng 
Link: https://android.googlesource.com/platform/external/u-boot/+/b4bb5227d4cf4fdfcd8b4e1ff2692d3a54d1482a
Reviewed-by: Simon Glass

virtio: pci: Tear down VQs in virtio_pci_reset()

2023-04-25T15:53:15+00:00

The pages backing the virtqueues for virtio PCI devices are not freed
on reset, despite the virtqueue structure being freed as part of the
driver '->priv_auto' destruction at ->remove() time.

Call virtio_pci_del_vqs() from virtio_pci_reset() to free the virtqueue
pages before freeing the virtqueue structure itself.

Signed-off-by: Will Deacon 
[ Paul: pick from the Android tree. Rebase to the upstream ]
Signed-off-by: Ying-Chun Liu (PaulLiu) 
Cc: Bin Meng 
Link: https://android.googlesource.com/platform/external/u-boot/+/5ed54ccd83cbffd0d8719ce650604b4e44b5b0d8
Reviewed-by: Simon Glass

virtio: Expose VIRTIO_F_IOMMU_PLATFORM in device features

2023-04-25T15:53:15+00:00

If we detect the VIRTIO_F_IOMMU_PLATFORM transport feature for a device,
then expose it in the device features.

Signed-off-by: Will Deacon 
[ Paul: pick from the Android tree. Rebase to the upstream ]
Signed-off-by: Ying-Chun Liu (PaulLiu) 
Cc: Bin Meng 
Link: https://android.googlesource.com/platform/external/u-boot/+/9693bd26bfcfe77d6a1295a561420e08c5daf019
Reviewed-by: Simon Glass