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/
v3: * s/pcimem64-start/reserved-memory-end/ v2: * place 64-bit window behind high RAM end if "etc/pcimem64-start" point below it. --- src/fw/pciinit.c | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-)
diff --git a/src/fw/pciinit.c b/src/fw/pciinit.c index b29db99..a714a5b 100644 --- a/src/fw/pciinit.c +++ b/src/fw/pciinit.c @@ -18,6 +18,8 @@ #include "paravirt.h" // RamSize #include "string.h" // memset #include "util.h" // pci_setup +#include "byteorder.h" // le64_to_cpu +#include "romfile.h" // romfile_loadint
#define PCI_DEVICE_MEM_MIN 0x1000 #define PCI_BRIDGE_IO_MIN 0x1000 @@ -764,6 +766,15 @@ 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], @@ -779,7 +790,7 @@ 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;
On Wed, 20 Nov 2013 01:08:33 +0100 Igor Mammedov imammedo@redhat.com wrote:
Sorry for noise, patch doesn't apply on top of current master. I'll resubmit rebased v5.
-
Igor Mammedov