@@ -19,6 +19,7 @@
*/
#include "hw/pci/pci.h"
+#include "hw/pci/pci_bridge.h"
#include "hw/pci/pci_host.h"
#include "trace.h"
@@ -48,9 +49,29 @@ static inline PCIDevice *pci_dev_find_by_addr(PCIBus *bus, uint32_t addr)
return pci_find_device(bus, bus_num, devfn);
}
+static void pci_adjust_config_limit(PCIBus *bus, uint32_t *limit)
+{
+ if (*limit > PCI_CONFIG_SPACE_SIZE) {
+ if (!pci_bus_is_express(bus)) {
+ *limit = PCI_CONFIG_SPACE_SIZE;
+ return;
+ }
+
+ if (!pci_bus_is_root(bus)) {
+ PCIDevice *bridge = pci_bridge_get_device(bus);
+ pci_adjust_config_limit(bridge->bus, limit);
+ }
+ }
+}
+
void pci_host_config_write_common(PCIDevice *pci_dev, uint32_t addr,
uint32_t limit, uint32_t val, uint32_t len)
{
+ pci_adjust_config_limit(pci_dev->bus, &limit);
+ if (limit <= addr) {
+ return;
+ }
+
assert(len <= 4);
trace_pci_cfg_write(pci_dev->name, PCI_SLOT(pci_dev->devfn),
PCI_FUNC(pci_dev->devfn), addr, val);
@@ -62,6 +83,11 @@ uint32_t pci_host_config_read_common(PCIDevice *pci_dev, uint32_t addr,
{
uint32_t ret;
+ pci_adjust_config_limit(pci_dev->bus, &limit);
+ if (limit <= addr) {
+ return ~0x0;
+ }
+
assert(len <= 4);
ret = pci_dev->config_read(pci_dev, addr, MIN(len, limit - addr));
trace_pci_cfg_read(pci_dev->name, PCI_SLOT(pci_dev->devfn),
A conventional PCI bus does not support config space accesses above the standard 256 byte configuration space. PCIe-to-PCI bridges are not permitted to forward transactions if the extended register address field is non-zero and must handle it as an unsupported request (PCIe bridge spec rev 1.0, 4.1.3, 4.1.4). Therefore, we should not support extended config space if there is a conventional bus anywhere on the path to a device. Signed-off-by: Alex Williamson <alex.williamson@redhat.com> --- hw/pci/pci_host.c | 26 ++++++++++++++++++++++++++ 1 file changed, 26 insertions(+)