qemu-e2k/docs/specs/pci-testdev.txt
Michael S. Tsirkin 22773d6066 pci: add pci test device
This device is used for kvm unit tests,
currently it supports testing performance of ioeventfd.
Using updated kvm unittest, here's an example output:
        mmio-no-eventfd:pci-mem 8796
        mmio-wildcard-eventfd:pci-mem 3609
        mmio-datamatch-eventfd:pci-mem 3685
        portio-no-eventfd:pci-io 5287
        portio-wildcard-eventfd:pci-io 1762
        portio-datamatch-eventfd:pci-io 1777

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2013-04-16 01:41:53 +03:00

27 lines
1.1 KiB
Plaintext

pci-test is a device used for testing low level IO
device implements up to two BARs: BAR0 and BAR1.
Each BAR can be memory or IO. Guests must detect
BAR type and act accordingly.
Each BAR size is up to 4K bytes.
Each BAR 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.