From 96a8d130a8c2e908e357ce62cd713f2cc0b0a2eb Mon Sep 17 00:00:00 2001 From: Gerd Hoffmann Date: Fri, 9 Sep 2022 10:17:15 +0200 Subject: [PATCH] be less conservative with the 64bit pci io window Current seabios code will only enable and use the 64bit pci io window in case it runs out of space in the 32bit pci mmio window below 4G. This patch will also enable the 64bit pci io window when (a) RAM above 4G is present, and (b) the physical address space size is known, and (c) seabios is running on a 64bit capable processor. This operates with the assumption that guests which are ok with memory above 4G most likely can handle mmio above 4G too. In case the 64bit pci io window is enabled also assign more memory to prefetchable pci bridge windows and the complete 64bit pci io window. The total mmio window size is 1/8 of the physical address space. Minimum bridge windows size is 1/256 of the total mmio window size. Signed-off-by: Gerd Hoffmann --- src/fw/pciinit.c | 16 ++++++++++++---- 1 file changed, 12 insertions(+), 4 deletions(-) diff --git a/src/fw/pciinit.c b/src/fw/pciinit.c index 0fcd2be5..b52bd1d5 100644 --- a/src/fw/pciinit.c +++ b/src/fw/pciinit.c @@ -51,6 +51,7 @@ u64 pcimem_end = BUILD_PCIMEM_END; u64 pcimem64_start = BUILD_PCIMEM64_START; u64 pcimem64_end = BUILD_PCIMEM64_END; u64 pci_io_low_end = 0xa000; +u32 pci_use_64bit = 0; struct pci_region_entry { struct pci_device *dev; @@ -960,10 +961,14 @@ static int pci_bios_check_devices(struct pci_bus *busses) if (pci_region_align(&s->r[type]) > align) align = pci_region_align(&s->r[type]); u64 sum = pci_region_sum(&s->r[type]); + int is64 = pci_bios_bridge_region_is64(&s->r[type], + s->bus_dev, type); int resource_optional = 0; if (hotplug_support == HOTPLUG_PCIE) resource_optional = pcie_cap && (type == PCI_REGION_TYPE_IO); - if (!sum && hotplug_support && !resource_optional) + if (hotplug_support && pci_use_64bit && is64 && (type == PCI_REGION_TYPE_PREFMEM)) + align = (u64)1 << (CPUPhysBits - 11); + if (align > sum && hotplug_support && !resource_optional) sum = align; /* reserve min size for hot-plug */ if (size > sum) { dprintf(1, "PCI: QEMU resource reserve cap: " @@ -975,8 +980,6 @@ static int pci_bios_check_devices(struct pci_bus *busses) } else { size = ALIGN(sum, align); } - int is64 = pci_bios_bridge_region_is64(&s->r[type], - s->bus_dev, type); // entry->bar is -1 if the entry represents a bridge region struct pci_region_entry *entry = pci_region_create_entry( parent, s->bus_dev, -1, size, align, type, is64); @@ -1108,7 +1111,7 @@ static void pci_bios_map_devices(struct pci_bus *busses) panic("PCI: out of I/O address space\n"); dprintf(1, "PCI: 32: %016llx - %016llx\n", pcimem_start, pcimem_end); - if (pci_bios_init_root_regions_mem(busses)) { + if (pci_use_64bit || pci_bios_init_root_regions_mem(busses)) { struct pci_region r64_mem, r64_pref; r64_mem.list.first = NULL; r64_pref.list.first = NULL; @@ -1132,6 +1135,8 @@ static void pci_bios_map_devices(struct pci_bus *busses) u64 top = 1LL << CPUPhysBits; u64 size = (ALIGN(sum_mem, (1LL<<30)) + ALIGN(sum_pref, (1LL<<30))); + if (pci_use_64bit) + size = ALIGN(size, (1LL<<(CPUPhysBits-3))); if (r64_mem.base < top - size) { r64_mem.base = top - size; } @@ -1174,6 +1179,9 @@ pci_setup(void) dprintf(3, "pci setup\n"); + if (CPUPhysBits >= 36 && CPULongMode && RamSizeOver4G) + pci_use_64bit = 1; + dprintf(1, "=== PCI bus & bridge init ===\n"); if (pci_probe_host() != 0) { return;