From 417463341e3e35c9be80f54b0d6ae8cfdb4b0d84 Mon Sep 17 00:00:00 2001 From: Gerd Hoffmann Date: Fri, 28 Sep 2018 08:44:19 +0200 Subject: pci-testdev: add optional memory bar MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 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 Reviewed-by: Laszlo Ersek Tested-by: Laszlo Ersek Signed-off-by: Gerd Hoffmann Reviewed-by: Michael S. Tsirkin Signed-off-by: Michael S. Tsirkin --- docs/specs/pci-testdev.txt | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-) (limited to 'docs/specs') diff --git a/docs/specs/pci-testdev.txt b/docs/specs/pci-testdev.txt index 128ae222ef..4280a1e73c 100644 --- a/docs/specs/pci-testdev.txt +++ b/docs/specs/pci-testdev.txt @@ -1,11 +1,11 @@ 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. +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. -Each BAR size is up to 4K bytes. -Each BAR starts with the following header: +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 @@ -24,3 +24,8 @@ 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= property. This +can be used to test whether guests handle pci bars of a specific +(possibly quite large) size correctly. -- cgit v1.2.3