On 06/03/18 09:16, Shawn Guo wrote: > On Mon, Mar 05, 2018 at 06:38:48PM +0530, Kishon Vijay Abraham I wrote: >> Hi Lorenzo, >> >> On Monday 05 March 2018 05:54 PM, Lorenzo Pieralisi wrote: >>> On Mon, Mar 05, 2018 at 08:55:43AM -0300, Fabio Estevam wrote: >>>> Hi Lorenzo, >>>> >>>> On Mon, Mar 5, 2018 at 6:49 AM, Lorenzo Pieralisi >>>> <lorenzo.pieralisi@xxxxxxx> wrote: >>>> >>>>> It is a balance of urgency and making sure it is extensively tested - >>>>> I'd prefer it to go via usual release cycle (and -next) and then it will >>>>> trickle into stable kernels, let me know if that's not OK. >>>>> >>>>> I would understand your point if dwc maintainers were more proactive >>>>> in testing their respective controllers - all of them should be affected >>>>> by this fix but I have just heard from a few of them. >>>> >>>> We got this patch tested by: Koen, myself, Sebastian and the folks at >>>> Pengutronix. >>>> >>>> Looks like a decent amount of testing IMHO. >>> >>> IIUC you all tested the same dwc host bridge variant (ie imx6) - I want >>> to understand if it works across dwc variants because this patch affects >>> them all. >>> >>>> In this case I would prefer that we could fix the regression into >>>> 4.16-rc cycle rather than waiting until 4.17. >>> >>> I will decide what to do shortly - I would really appreciate if other >>> dwc host bridge maintainers (that are CC'ed) can share the testing effort. >> >> For some reason I don't see the issues mentioned in this patch in dra7xx. The >> root bus has a subordinate bus number as 01 but I'm able to read the >> configuration space of the devices behind the bridge with bus number 2. I'll >> have to take a closer look at what exactly happens. > > Just for record, I do not seem to see this issue on pcie-histb driver > as well. Or did I miss anything? Shawn: You don't seem to have a PCIe switch, so your setup isn't affected by the bug. Kishon: Please add an endpoint device behind your switch, and retest. You will probably not see your endpoint device without this fix. On ARTPEC-6, 03:00.0 is only shown with this fix. On ARTPEC-6 without this fix: # lspci -v 00:00.0 Class 0604: Device 1912:0024 Flags: bus master, fast devsel, latency 0, IRQ 44 Memory at c0100000 (32-bit, prefetchable) [size=1M] Memory at c0200000 (32-bit, prefetchable) [size=1M] Bus: primary=00, secondary=01, subordinate=01, sec-latency=0 I/O behind bridge: None Memory behind bridge: None Prefetchable memory behind bridge: None Capabilities: [40] Power Management version 3 Capabilities: [50] MSI: Enable+ Count=1/1 Maskable+ 64bit+ Capabilities: [70] Express Root Port (Slot-), MSI 00 Capabilities: [b0] MSI-X: Enable- Count=1 Masked- Capabilities: [100] Advanced Error Reporting Kernel driver in use: pcieport 01:00.0 Class 0604: Device 12d8:2304 (rev 05) Flags: bus master, fast devsel, latency 0 Bus: primary=01, secondary=02, subordinate=04, sec-latency=0 I/O behind bridge: None Memory behind bridge: None Prefetchable memory behind bridge: None Capabilities: [40] Power Management version 3 Capabilities: [5c] Vital Product Data Capabilities: [64] Vendor Specific Information: Len=34 <?> Capabilities: [b0] Subsystem: Device 0000:0000 Capabilities: [c0] Express Upstream Port, MSI 00 Capabilities: [100] Advanced Error Reporting Capabilities: [140] Virtual Channel Capabilities: [20c] Power Budgeting <?> Capabilities: [230] Latency Tolerance Reporting Kernel driver in use: pcieport 02:01.0 Class 0604: Device 12d8:2304 (rev 05) Flags: bus master, fast devsel, latency 0, IRQ 45 Bus: primary=02, secondary=03, subordinate=03, sec-latency=0 I/O behind bridge: None Memory behind bridge: None Prefetchable memory behind bridge: None Capabilities: [40] Power Management version 3 Capabilities: [4c] MSI: Enable+ Count=1/1 Maskable- 64bit+ Capabilities: [64] Vendor Specific Information: Len=34 <?> Capabilities: [b0] Subsystem: Device 0000:0000 Capabilities: [c0] Express Downstream Port (Slot+), MSI 00 Capabilities: [100] Advanced Error Reporting Capabilities: [140] Virtual Channel Capabilities: [20c] Power Budgeting <?> Capabilities: [220] Access Control Services Kernel driver in use: pcieport 02:02.0 Class 0604: Device 12d8:2304 (rev 05) Flags: bus master, fast devsel, latency 0, IRQ 46 Bus: primary=02, secondary=04, subordinate=04, sec-latency=0 I/O behind bridge: None Memory behind bridge: None Prefetchable memory behind bridge: None Capabilities: [40] Power Management version 3 Capabilities: [4c] MSI: Enable+ Count=1/1 Maskable- 64bit+ Capabilities: [64] Vendor Specific Information: Len=34 <?> Capabilities: [b0] Subsystem: Device 0000:0000 Capabilities: [c0] Express Downstream Port (Slot+), MSI 00 Capabilities: [100] Advanced Error Reporting Capabilities: [140] Virtual Channel Capabilities: [20c] Power Budgeting <?> Capabilities: [220] Access Control Services Kernel driver in use: pcieport On ARTPEC-6 with this fix: # lspci -v 00:00.0 Class 0604: Device 1912:0024 Flags: bus master, fast devsel, latency 0, IRQ 44 Memory at c0100000 (32-bit, prefetchable) [size=1M] Memory at c0200000 (32-bit, prefetchable) [size=1M] Bus: primary=00, secondary=01, subordinate=ff, sec-latency=0 I/O behind bridge: None Memory behind bridge: c0300000-c03fffff [size=1M] Prefetchable memory behind bridge: None Capabilities: [40] Power Management version 3 Capabilities: [50] MSI: Enable+ Count=1/1 Maskable+ 64bit+ Capabilities: [70] Express Root Port (Slot-), MSI 00 Capabilities: [b0] MSI-X: Enable- Count=1 Masked- Capabilities: [100] Advanced Error Reporting Kernel driver in use: pcieport 01:00.0 Class 0604: Device 12d8:2304 (rev 05) Flags: bus master, fast devsel, latency 0 Bus: primary=01, secondary=02, subordinate=04, sec-latency=0 I/O behind bridge: None Memory behind bridge: c0300000-c03fffff [size=1M] Prefetchable memory behind bridge: None Capabilities: [40] Power Management version 3 Capabilities: [5c] Vital Product Data Capabilities: [64] Vendor Specific Information: Len=34 <?> Capabilities: [b0] Subsystem: Device 0000:0000 Capabilities: [c0] Express Upstream Port, MSI 00 Capabilities: [100] Advanced Error Reporting Capabilities: [140] Virtual Channel Capabilities: [20c] Power Budgeting <?> Capabilities: [230] Latency Tolerance Reporting Kernel driver in use: pcieport 02:01.0 Class 0604: Device 12d8:2304 (rev 05) Flags: bus master, fast devsel, latency 0, IRQ 45 Bus: primary=02, secondary=03, subordinate=03, sec-latency=0 I/O behind bridge: None Memory behind bridge: c0300000-c03fffff [size=1M] Prefetchable memory behind bridge: None Capabilities: [40] Power Management version 3 Capabilities: [4c] MSI: Enable+ Count=1/1 Maskable- 64bit+ Capabilities: [64] Vendor Specific Information: Len=34 <?> Capabilities: [b0] Subsystem: Device 0000:0000 Capabilities: [c0] Express Downstream Port (Slot+), MSI 00 Capabilities: [100] Advanced Error Reporting Capabilities: [140] Virtual Channel Capabilities: [20c] Power Budgeting <?> Capabilities: [220] Access Control Services Kernel driver in use: pcieport 02:02.0 Class 0604: Device 12d8:2304 (rev 05) Flags: bus master, fast devsel, latency 0, IRQ 46 Bus: primary=02, secondary=04, subordinate=04, sec-latency=0 I/O behind bridge: None Memory behind bridge: None Prefetchable memory behind bridge: None Capabilities: [40] Power Management version 3 Capabilities: [4c] MSI: Enable+ Count=1/1 Maskable- 64bit+ Capabilities: [64] Vendor Specific Information: Len=34 <?> Capabilities: [b0] Subsystem: Device 0000:0000 Capabilities: [c0] Express Downstream Port (Slot+), MSI 00 Capabilities: [100] Advanced Error Reporting Capabilities: [140] Virtual Channel Capabilities: [20c] Power Budgeting <?> Capabilities: [220] Access Control Services Kernel driver in use: pcieport 03:00.0 Class 0c03: Device 1912:0015 (rev 02) (prog-if 30) Flags: fast devsel Memory at c0300000 (64-bit, non-prefetchable) [size=8K] Capabilities: [50] Power Management version 3 Capabilities: [70] MSI: Enable- Count=1/8 Maskable- 64bit+ Capabilities: [90] MSI-X: Enable- Count=8 Masked- Capabilities: [a0] Express Endpoint, MSI 00 Capabilities: [100] Advanced Error Reporting Capabilities: [150] Latency Tolerance Reporting Best regards, Niklas
