On Fri, Mar 12, 2021 at 07:28:49PM +0100, Philippe Mathieu-Daudé wrote:
> The pci_io_non_contiguous region is mapped on top of pci_io
> with higher priority, but simply dispatch into this region
> address space. Simplify by directly registering the former
> region in place, and adapt the address space dispatch offsets.
>
> Signed-off-by: Philippe Mathieu-Daudé <f4...@amsat.org>
> ---
> hw/pci-host/prep.c | 11 ++++-------
> 1 file changed, 4 insertions(+), 7 deletions(-)
>
> diff --git a/hw/pci-host/prep.c b/hw/pci-host/prep.c
> index 0a9162fba97..00a28c2d18c 100644
> --- a/hw/pci-host/prep.c
> +++ b/hw/pci-host/prep.c
> @@ -159,8 +159,7 @@ static uint64_t raven_io_read(void *opaque, hwaddr addr,
> uint8_t buf[4];
>
> addr = raven_io_address(s, addr);
> - address_space_read(&s->pci_io_as, addr + 0x80000000,
> - MEMTXATTRS_UNSPECIFIED, buf, size);
> + address_space_read(&s->pci_io_as, addr, MEMTXATTRS_UNSPECIFIED, buf,
> size);
>
> if (size == 1) {
> return buf[0];
> @@ -191,8 +190,7 @@ static void raven_io_write(void *opaque, hwaddr addr,
> g_assert_not_reached();
> }
>
> - address_space_write(&s->pci_io_as, addr + 0x80000000,
> - MEMTXATTRS_UNSPECIFIED, buf, size);
> + address_space_write(&s->pci_io_as, addr, MEMTXATTRS_UNSPECIFIED, buf,
> size);
This changes access to s->pci_io_as, but below didn't change s->pci_io_as
layout at all (below is about address_space_mem). Is this intended?
> }
>
> static const MemoryRegionOps raven_io_ops = {
> @@ -294,9 +292,8 @@ static void raven_pcihost_initfn(Object *obj)
> address_space_init(&s->pci_io_as, &s->pci_io, "raven-io");
>
> /* CPU address space */
> - memory_region_add_subregion(address_space_mem, 0x80000000, &s->pci_io);
> - memory_region_add_subregion_overlap(address_space_mem, 0x80000000,
> - &s->pci_io_non_contiguous, 1);
> + memory_region_add_subregion(address_space_mem, 0x80000000,
> + &s->pci_io_non_contiguous);
I don't know any of this code at all... but it seems the two memory regions are
not identical in size:
memory_region_init(&s->pci_io, obj, "pci-io", 0x3f800000);
memory_region_init_io(&s->pci_io_non_contiguous, obj, &raven_io_ops, s,
"pci-io-non-contiguous", 0x00800000);
Then it seems the memory access dispatching to (0x00800000, 0x3f800000) would
change too, from s->pci_io to nothing. Raise this up too since I don't know
either whether it's intended..
> memory_region_add_subregion(address_space_mem, 0xc0000000,
> &s->pci_memory);
> pci_root_bus_new_inplace(&s->pci_bus, sizeof(s->pci_bus), DEVICE(obj),
> NULL,
> &s->pci_memory, &s->pci_io, 0, TYPE_PCI_BUS);
> --
> 2.26.2
>
--
Peter Xu
