On Mon, 9 Mar 2020, Michael S. Tsirkin wrote:
On Mon, Mar 09, 2020 at 08:18:13PM +0100, BALATON Zoltan wrote:
The pci_do_device_reset() function (called from pci_device_reset)
clears the PCI_INTERRUPT_LINE config reg of devices on the bus but did
this without taking wmask into account. We'll have a device model now
that needs to set a constant value for this reg and this patch allows
to do that without additional workaround in device emulation to
reverse the effect of this PCI bus reset function.
Suggested-by: Mark Cave-Ayland <mark.cave-ayl...@ilande.co.uk>
Signed-off-by: BALATON Zoltan <bala...@eik.bme.hu>
---
hw/pci/pci.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/hw/pci/pci.c b/hw/pci/pci.c
index e1ed6677e1..d07e4ed9de 100644
--- a/hw/pci/pci.c
+++ b/hw/pci/pci.c
@@ -302,8 +302,10 @@ static void pci_do_device_reset(PCIDevice *dev)
pci_word_test_and_clear_mask(dev->config + PCI_STATUS,
pci_get_word(dev->wmask + PCI_STATUS) |
pci_get_word(dev->w1cmask + PCI_STATUS));
+ pci_word_test_and_clear_mask(dev->config + PCI_INTERRUPT_LINE,
+ pci_get_word(dev->wmask + PCI_INTERRUPT_LINE) |
+ pci_get_word(dev->w1cmask + PCI_INTERRUPT_LINE));
PCI spec says:
Interrupt Line
The Interrupt Line register is an eight-bit register used to communicate
interrupt line routing
information.
I don't see how it makes sense to access it as a word.
Patch actually comes from Mark, I don't know. Should we change it to
pci_byte_test_and_clear_mask or what's the appropriate way here?
dev->config[PCI_CACHE_LINE_SIZE] = 0x0;
- dev->config[PCI_INTERRUPT_LINE] = 0x0;
for (r = 0; r < PCI_NUM_REGIONS; ++r) {
PCIIORegion *region = &dev->io_regions[r];
if (!region->size) {
Please add comments here explaining that some devices
make PCI_INTERRUPT_LINE read-only.
Something like the commit message would be appropriate?
Regards,
BALATON Zoltan
