On Wed, Aug 02, 2017 at 02:17:42PM +0200, Paul Menzel wrote: > Dear Linux folks, > > > Trying to improve the start-up time of a (slow) ASRock E350M1 which already > uses coreboot, when instrumenting the time of the Linux Kernel, execution of > `ohci_pci_init()` takes almost 200 ms. > > ``` > […] > > [ 0.000000] Kernel command line: BOOT_IMAGE=/boot/vmlinuz-4.13.0-rc3+ root=UUID=128529e0-b8bb-4c7d-956d-ddf699036c8c ro noisapnp initcall_debug log_buf_len=32M trace_buf_size=128M trace_clock=global trace_options=nooverwrite,funcgraph-abstime,funcgraph-cpu,funcgraph-duration,funcgraph-proc,funcgraph-tail,nofuncgraph-overhead,context-info,graph-time ftrace=function_graph ftrace_graph_max_depth=2 ftrace_graph_filter=do_one_initcall > […] > [ 2.181189] calling ohci_pci_init+0x0/0x1000 [ohci_pci] @ 168 > [ 2.181268] ohci-pci: OHCI PCI platform driver > [ 2.182058] ohci-pci 0000:00:12.0: OHCI PCI host controller > [ 2.182135] ohci-pci 0000:00:12.0: new USB bus registered, assigned bus > number 3 > [ 2.182290] ohci-pci 0000:00:12.0: irq 18, io mem 0xf0148000 > [ 2.244664] usb usb3: New USB device found, idVendor=1d6b, idProduct=0001 > [ 2.244809] usb usb3: New USB device strings: Mfr=3, Product=2, > SerialNumber=1 > [ 2.244879] usb usb3: Product: OHCI PCI host controller > [ 2.244939] usb usb3: Manufacturer: Linux 4.13.0-rc3+ ohci_hcd > [ 2.244999] usb usb3: SerialNumber: 0000:00:12.0 > [ 2.245486] hub 3-0:1.0: USB hub found > [ 2.245637] hub 3-0:1.0: 5 ports detected > [ 2.252384] ohci-pci 0000:00:13.0: OHCI PCI host controller > [ 2.252484] ohci-pci 0000:00:13.0: new USB bus registered, assigned bus > number 4 > [ 2.252634] ohci-pci 0000:00:13.0: irq 18, io mem 0xf0149000 > [ 2.316458] usb usb4: New USB device found, idVendor=1d6b, idProduct=0001 > [ 2.316604] usb usb4: New USB device strings: Mfr=3, Product=2, > SerialNumber=1 > [ 2.316675] usb usb4: Product: OHCI PCI host controller > [ 2.316733] usb usb4: Manufacturer: Linux 4.13.0-rc3+ ohci_hcd > [ 2.316793] usb usb4: SerialNumber: 0000:00:13.0 > [ 2.317666] hub 4-0:1.0: USB hub found > [ 2.317830] hub 4-0:1.0: 5 ports detected > [ 2.319124] ohci-pci 0000:00:14.5: OHCI PCI host controller > [ 2.319199] ohci-pci 0000:00:14.5: new USB bus registered, assigned bus > number 5 > [ 2.319341] ohci-pci 0000:00:14.5: irq 18, io mem 0xf014a000 > [ 2.380239] usb usb5: New USB device found, idVendor=1d6b, idProduct=0001 > [ 2.380383] usb usb5: New USB device strings: Mfr=3, Product=2, > SerialNumber=1 > [ 2.380453] usb usb5: Product: OHCI PCI host controller > [ 2.380512] usb usb5: Manufacturer: Linux 4.13.0-rc3+ ohci_hcd > [ 2.380571] usb usb5: SerialNumber: 0000:00:14.5 > [ 2.381189] hub 5-0:1.0: USB hub found > [ 2.382135] hub 5-0:1.0: 2 ports detected > [ 2.382766] initcall ohci_pci_init+0x0/0x1000 [ohci_pci] returned 0 after > 196766 usecs > […] > ``` > > It looks like this is not done in parallel, so all the next “tasks” have to > wait until `ohci_pci_init()` is done. > > Do you know of a way to redcuce that time? Please find all the Linux > messages attached. As USB is async for device discovery, this shouldn't be keeping your boot process from continuing on, right? If you have this as a kernel module and load it later, it should be fine. That being said, look in the driver itself to see what is taking a while, some devices are just slow to initialize themselves for various reasons that all are due to the hardware design :( good luck! greg k-h -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
