mirror of
https://github.com/xemu-project/xemu.git
synced 2024-12-11 21:44:04 +00:00
417463341e
Add memory bar to pci-testdev. Size is configurable using the membar property. Setting the size to zero (default) turns it off. Can be used to check whether guests handle large pci bars correctly. Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com> Reviewed-by: Laszlo Ersek <lersek@redhat.com> Tested-by: Laszlo Ersek <lersek@redhat.com> Signed-off-by: Gerd Hoffmann <kraxel@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
32 lines
1.4 KiB
Plaintext
32 lines
1.4 KiB
Plaintext
pci-test is a device used for testing low level IO
|
|
|
|
device implements up to three BARs: BAR0, BAR1 and BAR2.
|
|
Each of BAR 0+1 can be memory or IO. Guests must detect
|
|
BAR types and act accordingly.
|
|
|
|
BAR 0+1 size is up to 4K bytes each.
|
|
BAR 0+1 starts with the following header:
|
|
|
|
typedef struct PCITestDevHdr {
|
|
uint8_t test; <- write-only, starts a given test number
|
|
uint8_t width_type; <- read-only, type and width of access for a given test.
|
|
1,2,4 for byte,word or long write.
|
|
any other value if test not supported on this BAR
|
|
uint8_t pad0[2];
|
|
uint32_t offset; <- read-only, offset in this BAR for a given test
|
|
uint32_t data; <- read-only, data to use for a given test
|
|
uint32_t count; <- for debugging. number of writes detected.
|
|
uint8_t name[]; <- for debugging. 0-terminated ASCII string.
|
|
} PCITestDevHdr;
|
|
|
|
All registers are little endian.
|
|
|
|
device is expected to always implement tests 0 to N on each BAR, and to add new
|
|
tests with higher numbers. In this way a guest can scan test numbers until it
|
|
detects an access type that it does not support on this BAR, then stop.
|
|
|
|
BAR2 is a 64bit memory bar, without backing storage. It is disabled
|
|
by default and can be enabled using the membar=<size> property. This
|
|
can be used to test whether guests handle pci bars of a specific
|
|
(possibly quite large) size correctly.
|