From 3aa31d7d6375303fc88438021aad485f50bb1e39 Mon Sep 17 00:00:00 2001 Message-Id: <3aa31d7d6375303fc88438021aad485f50bb1e39.1404919343.git.crobinso@redhat.com> From: Marcel Apfelbaum Date: Mon, 23 Jun 2014 18:29:51 +0300 Subject: [PATCH] hw/pci: reserve IO and mem for pci express downstream ports with no devices attached Commit c6e298e1f12e0f4ca02b6da5e42919ae055f6830 hw/pci: reserve IO and mem for pci-2-pci bridges with no devices attached introduced support for hot-plugging devices behind pci-2-pci bridges. Extend hotplug support also for pci express downstream ports. Signed-off-by: Marcel Apfelbaum Signed-off-by: Gerd Hoffmann --- src/fw/pciinit.c | 34 ++++++++++++++++++++++++++++++++-- 1 file changed, 32 insertions(+), 2 deletions(-) diff --git a/src/fw/pciinit.c b/src/fw/pciinit.c index 0ad548f..fd5dfb9 100644 --- a/src/fw/pciinit.c +++ b/src/fw/pciinit.c @@ -636,6 +636,36 @@ pci_region_create_entry(struct pci_bus *bus, struct pci_device *dev, return entry; } +static int pci_bus_hotplug_support(struct pci_bus *bus) +{ + u8 pcie_cap = pci_find_capability(bus->bus_dev, PCI_CAP_ID_EXP); + u8 shpc_cap; + + if (pcie_cap) { + u16 pcie_flags = pci_config_readw(bus->bus_dev->bdf, + pcie_cap + PCI_EXP_FLAGS); + u8 port_type = ((pcie_flags & PCI_EXP_FLAGS_TYPE) >> + (__builtin_ffs(PCI_EXP_FLAGS_TYPE) - 1)); + u8 downstream_port = (port_type == PCI_EXP_TYPE_DOWNSTREAM) || + (port_type == PCI_EXP_TYPE_ROOT_PORT); + /* + * PCI Express SPEC, 7.8.2: + * Slot Implemented – When Set, this bit indicates that the Link + * HwInit associated with this Port is connected to a slot (as + * compared to being connected to a system-integrated device or + * being disabled). + * This bit is valid for Downstream Ports. This bit is undefined + * for Upstream Ports. + */ + u16 slot_implemented = pcie_flags & PCI_EXP_FLAGS_SLOT; + + return downstream_port && slot_implemented; + } + + shpc_cap = pci_find_capability(bus->bus_dev, PCI_CAP_ID_SHPC); + return !!shpc_cap; +} + static int pci_bios_check_devices(struct pci_bus *busses) { dprintf(1, "PCI: check devices\n"); @@ -678,7 +708,7 @@ static int pci_bios_check_devices(struct pci_bus *busses) continue; struct pci_bus *parent = &busses[pci_bdf_to_bus(s->bus_dev->bdf)]; int type; - u8 shpc_cap = pci_find_capability(s->bus_dev, PCI_CAP_ID_SHPC); + int hotplug_support = pci_bus_hotplug_support(s); for (type = 0; type < PCI_REGION_TYPE_COUNT; type++) { u64 align = (type == PCI_REGION_TYPE_IO) ? PCI_BRIDGE_IO_MIN : PCI_BRIDGE_MEM_MIN; @@ -687,7 +717,7 @@ 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]); - if (!sum && shpc_cap) + if (!sum && hotplug_support) sum = align; /* reserve min size for hot-plug */ u64 size = ALIGN(sum, align); int is64 = pci_bios_bridge_region_is64(&s->r[type], -- 1.9.3