@@ -15,6 +15,7 @@
#include "paravirt.h" // RamSize
#include "dev-q35.h" // Q35_HOST_BRIDGE_PCIEXBAR_ADDR
#include "list.h" // struct hlist_node
+#include "byteorder.h" // le64_to_cpu
/* PM Timer ticks per second (HZ) */
#define PM_TIMER_FREQUENCY 3579545
@@ -762,6 +763,15 @@ static void pci_bios_map_devices(struct pci_bus *busses)
{
if (pci_bios_init_root_regions(busses)) {
struct pci_region r64_mem, r64_pref;
+ u64 ram64_end = 0x100000000ULL + RamSizeOver4G;
+ u64 base64 = le64_to_cpu(romfile_loadint("etc/reserved-memory-end",
+ ram64_end));
+ if (base64 < ram64_end) {
+ dprintf(1, "ignorig etc/reserved-memory-end [0x%llx] below present"
+ " RAM, placing 64-bit PCI window behind RAM end: %llx",
+ base64, ram64_end);
+ base64 = ram64_end;
+ }
r64_mem.list.first = NULL;
r64_pref.list.first = NULL;
pci_region_migrate_64bit_entries(&busses[0].r[PCI_REGION_TYPE_MEM],
@@ -777,7 +787,7 @@ static void pci_bios_map_devices(struct pci_bus *busses)
u64 align_mem = pci_region_align(&r64_mem);
u64 align_pref = pci_region_align(&r64_pref);
- r64_mem.base = ALIGN(0x100000000LL + RamSizeOver4G, align_mem);
+ r64_mem.base = ALIGN(base64, align_mem);
r64_pref.base = ALIGN(r64_mem.base + sum_mem, align_pref);
pcimem64_start = r64_mem.base;
pcimem64_end = r64_pref.base + sum_pref;
Currently 64-bit PCI BARs are unconditionally mapped by BIOS right over 4G + RamSizeOver4G location, which doesn't allow to reserve extra space before 64-bit PCI window. For memory hotplug an extra RAM space might be reserved after present 64-bit RAM end and BIOS should map 64-bit PCI BARs after it. Introduce "etc/reserved-memory-end" romfile to provide BIOS a hint where it should start mapping of 64-bit PCI BARs. If romfile is missing, BIOS reverts to legacy behavior and starts mapping after high memory. Signed-off-by: Igor Mammedov <imammedo@redhat.com> --- Corresponding QEMU patch is here: http://patchwork.ozlabs.org/patch/291417/ v4,5: * rebasing on top of current master v3: * s/pcimem64-start/reserved-memory-end/ v2: * place 64-bit window behind high RAM end if "etc/pcimem64-start" point below it. --- src/pciinit.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-)