@@ -314,6 +314,8 @@ void pci_register_vga(PCIDevice *pci_dev, MemoryRegion *mem,
MemoryRegion *io_lo, MemoryRegion *io_hi);
void pci_unregister_vga(PCIDevice *pci_dev);
pcibus_t pci_get_bar_addr(PCIDevice *pci_dev, int region_num);
+pcibus_t pci_bar_address(PCIDevice *d, int reg, uint8_t type, pcibus_t size,
+ bool respect_command);
int pci_add_capability(PCIDevice *pdev, uint8_t cap_id,
uint8_t offset, uint8_t size);
@@ -1054,15 +1054,19 @@ pcibus_t pci_get_bar_addr(PCIDevice *pci_dev, int region_num)
return pci_dev->io_regions[region_num].addr;
}
-static pcibus_t pci_bar_address(PCIDevice *d,
- int reg, uint8_t type, pcibus_t size)
+pcibus_t pci_bar_address(PCIDevice *d, int reg, uint8_t type, pcibus_t size,
+ bool respect_command)
{
pcibus_t new_addr, last_addr;
int bar = pci_bar(d, reg);
- uint16_t cmd = pci_get_word(d->config + PCI_COMMAND);
+ uint16_t cmd;
+
+ if (respect_command) {
+ cmd = pci_get_word(d->config + PCI_COMMAND);
+ }
if (type & PCI_BASE_ADDRESS_SPACE_IO) {
- if (!(cmd & PCI_COMMAND_IO)) {
+ if (respect_command && !(cmd & PCI_COMMAND_IO)) {
return PCI_BAR_UNMAPPED;
}
new_addr = pci_get_long(d->config + bar) & ~(size - 1);
@@ -1076,7 +1080,7 @@ static pcibus_t pci_bar_address(PCIDevice *d,
return new_addr;
}
- if (!(cmd & PCI_COMMAND_MEMORY)) {
+ if (respect_command && !(cmd & PCI_COMMAND_MEMORY)) {
return PCI_BAR_UNMAPPED;
}
if (type & PCI_BASE_ADDRESS_MEM_TYPE_64) {
@@ -1134,7 +1138,7 @@ static void pci_update_mappings(PCIDevice *d)
if (!r->size)
continue;
- new_addr = pci_bar_address(d, i, r->type, r->size);
+ new_addr = pci_bar_address(d, i, r->type, r->size, true);
/* This bar isn't changed */
if (new_addr == r->addr)
@@ -2427,7 +2431,7 @@ static void pci_dev_get_w64(PCIBus *b, PCIDevice *dev, void *opaque)
!(r->type & PCI_BASE_ADDRESS_MEM_TYPE_64)) {
continue;
}
- region_range.begin = pci_bar_address(dev, i, r->type, r->size);
+ region_range.begin = pci_bar_address(dev, i, r->type, r->size, true);
region_range.end = region_range.begin + r->size;
if (region_range.begin == PCI_BAR_UNMAPPED) {
The pci_bar_address() function calculates the start address of a given PCI BAR. Its main purpose is supporting MemoryRegion mapping / unmapping in pci_update_mappings(), which is guest-observable. For that reason it contains heavy logic to enforce the validity of the BAR, and this logic includes checks for the PCI command register: - If the PCI_COMMAND_IO bit is clear in the command register, then all IO space BARs will be reported unmapped (all bits one), - If the PCI_COMMAND_MEMORY bit is clear in the command register, then all MMIO space BARs will be reported unmapped (all bits one). For an upcoming use case, we'd like pci_bar_address() to calculate the BAR address from the config space *regardless* of the command register. Add a new parameter that allows the caller to cut out the command register verification. All current callers preserve their behaviors. Cc: Marcel Apfelbaum <marcel@redhat.com> Cc: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Laszlo Ersek <lersek@redhat.com> --- include/hw/pci/pci.h | 2 ++ hw/pci/pci.c | 18 +++++++++++------- 2 files changed, 13 insertions(+), 7 deletions(-)