On Thu, 2014-06-19 at 17:21 +0300, Michael S. Tsirkin wrote:
On Thu, Jun 19, 2014 at 04:52:17PM +0300, Marcel Apfelbaum wrote:
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 marcel.a@redhat.com
src/fw/pciinit.c | 23 +++++++++++++++++++++-- src/hw/pci_regs.h | 2 ++ 2 files changed, 23 insertions(+), 2 deletions(-)
diff --git a/src/fw/pciinit.c b/src/fw/pciinit.c index 0ad548f..edb3fe9 100644 --- a/src/fw/pciinit.c +++ b/src/fw/pciinit.c @@ -636,6 +636,25 @@ 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 shpc_cap = pci_find_capability(bus->bus_dev, PCI_CAP_ID_SHPC);
- u8 pcie_cap = pci_find_capability(bus->bus_dev, PCI_CAP_ID_EXP);
- int downstream_port = 0;
- int slot_implemented = 0;
- if (pcie_cap) {
u16 pcie_flags = pci_config_readw(bus->bus_dev->bdf,pcie_cap + PCI_EXP_FLAGS);u16 port_type = ((pcie_flags & PCI_EXP_FLAGS_TYPE) >>PCI_EXP_FLAGS_TYPE_SHIFT) & 0xf;0xf is not needed here: PCI_EXP_FLAGS_TYPE is enough. Also should be u8.
OK, thanks
downstream_port = (port_type == PCI_EXP_TYPE_DOWNSTREAM) ||(port_type == PCI_EXP_TYPE_ROOT_PORT);This is correct, the spec says: Configuration Space, and other capabilities. 8 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.
Maybe add a comment in case people will wonder.
Sure
slot_implemented = !!(pcie_flags & PCI_EXP_FLAGS_SLOT);I would do return downstream_port && slot_implemented; here, avoid testing shpc for express devices.
Also allows moving downstream_port && slot_implemented here.
Makes sense
- }
- return shpc_cap || (downstream_port && slot_implemented);
+}
static int pci_bios_check_devices(struct pci_bus *busses) { dprintf(1, "PCI: check devices\n"); @@ -678,7 +697,7 @@ 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 +706,7 @@ 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],diff --git a/src/hw/pci_regs.h b/src/hw/pci_regs.h index e5effd4..6a71569 100644 --- a/src/hw/pci_regs.h +++ b/src/hw/pci_regs.h @@ -426,6 +426,8 @@ #define PCI_EXP_DEVCTL2 40 /* Device Control 2 */ #define PCI_EXP_DEVCTL2_ARI 0x20 /* Alternative Routing-ID */
+#define PCI_EXP_FLAGS_TYPE_SHIFT 4
It's generally not a good idea to randomly add macros in random places. In this case this is not needed. Just call __ffs on PCI_EXP_FLAGS_TYPE.
I didn't see any usage of __ffs method on seabios code, so I wondered if adding an include to string.h would be ok. Would it?
Thanks, Marcel
/* Extended Capabilities (PCI-X 2.0 and Express) */ #define PCI_EXT_CAP_ID(header) (header & 0x0000ffff)
#define PCI_EXT_CAP_VER(header) ((header >> 16) & 0xf)
1.8.3.1