On 6/16/25 10:03 AM, Alice Ryhl wrote:
On Wed, May 14, 2025 at 12:58 PM Andrew Ballance
<andrewjballa...@gmail.com> wrote:
currently the rust `Io` type maps to the c read{b, w, l, q}/write{b, w, l, q}
functions and have no support for port io. this can be a problem for pci::Bar
because the pointer returned by pci_iomap can be either PIO or MMIO [0].
this patch series splits the `Io` type into `Io`, and `MMIo`. `Io` can be
used to access PIO or MMIO. `MMIo` can only access memory mapped IO but
might, depending on the arch, be faster than `Io`. and updates pci::Bar,
so that it is generic over Io and, a user can optionally give a compile
time hint about the type of io.
Link: https://docs.kernel.org/6.11/driver-api/pci/pci.html#c.pci_iomap [0]
This series seems to try and solve parts of the same problems as
Daniel's patchset:
https://lore.kernel.org/rust-for-linux/20250603-topics-tyr-platform_iomem-v9-0-a27e04157...@collabora.com/#r
We should probably align these two patchsets so that they do not add
incompatible abstractions for the same thing.
AFAICS, they solve different problems, i.e.
1) Add Port I/O support to the generic I/O abstractions.
2) Add an abstraction for generic ioremap() used to map a struct resource
obtained from a platform device.
The patch series will conflict though, I think it would be best to rebase this
one onto Daniel's patch series, since it is close to land.
