On 2018-12-17 11:19 a.m., Bjorn Helgaas wrote: > I *think* drivers/pci/switch/switchtec.c is for a type 0 endpoint that > happens to be built into the switch, e.g., the type 1 bridge is > function 0 and the type 0 management endpoint is function 1. Logan, > can you confirm/deny? Yes, that's correct. The upstream port has multiple functions: one for the bridge and one for the management/NTB endpoint. In the driver, we have absolutely no reason to touch, or even know about, the bridge endpoint. This is all very configurable and you can disable either of the endpoints in the switch's configuration. And the NTB endpoint can have all the BARS configured with any reasonable amount of BAR space for memory windows. In the NTB world, there are never enough BARs or address space within them. The upstream device, with both functions, looks like this on my system: 02:00.0 PCI bridge: PMC-Sierra Inc. Device 8543 (prog-if 00 [Normal decode]) Flags: bus master, fast devsel, latency 0, NUMA node 0 Bus: primary=02, secondary=03, subordinate=0c, sec-latency=0 I/O behind bridge: 00002000-00006fff Memory behind bridge: f7100000-f78fffff Prefetchable memory behind bridge: 0000381f80000000-0000381fc3ffffff Capabilities: [40] Express Upstream Port, MSI 00 Capabilities: [7c] MSI: Enable- Count=1/8 Maskable- 64bit+ Capabilities: [8c] Power Management version 3 Capabilities: [94] Subsystem: PMC-Sierra Inc. Device beef Capabilities: [100] Advanced Error Reporting Capabilities: [138] Power Budgeting <?> Capabilities: [148] #12 Capabilities: [178] #19 Capabilities: [1a4] Device Serial Number 50-0e-00-4a-00-00-00-01 Capabilities: [1b0] Latency Tolerance Reporting Capabilities: [1b8] Access Control Services Capabilities: [7f8] Vendor Specific Information: ID=ffff Rev=1 Len=808 <?> Kernel driver in use: pcieport 02:00.1 Memory controller: PMC-Sierra Inc. Device 8543 Subsystem: PMC-Sierra Inc. Device 8543 Flags: bus master, fast devsel, latency 0, NUMA node 0 Memory at 381fc4000000 (64-bit, prefetchable) [size=4M] Capabilities: [40] MSI: Enable- Count=1/4 Maskable- 64bit+ Capabilities: [50] MSI-X: Enable+ Count=4 Masked- Capabilities: [5c] Power Management version 3 Capabilities: [64] Express Endpoint, MSI 00 Capabilities: [100] Advanced Error Reporting Capabilities: [138] Device Serial Number 50-0e-00-4a-00-00-00-01 Capabilities: [144] Access Control Services Kernel driver in use: switchtec Kernel modules: switchtec Logan
