* Randy Dunlap <randy.dunlap@xxxxxxxxxx> wrote: > Yinghai Lu wrote: > > On Tue, Mar 3, 2009 at 3:53 PM, Sarah Sharp <sarah.a.sharp@xxxxxxxxx> wrote: > >> Greetings, > >> > >> You wrote the EHCI debug port patch for early printk back in July 2008 > >> (commit 5c05917e7fe313a187ad6ebb94c1c6cf42862a0b). Can you add some > >> documentation to the Documentation directory about how a Linux user > >> would set up a system (cables, files to open to get the printks, etc.)? > > > > please check > > > > ========================================================================================== > > USB Debug port using Howto > > > > 1. HW: > > > > a. target system need to have debug port > > > > 00:1d.7 USB Controller: Intel Corporation 82801H (ICH8 Family) USB2 > > EHCI Controller #1 (rev 03) (prog-if 20 [EHCI]) > > Subsystem: Lenovo ThinkPad T61 > > Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- > > ParErr- Stepping- SERR+ FastB2B- DisINTx- > > Status: Cap+ 66MHz- UDF- FastB2B+ ParErr- DEVSEL=medium > >> TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx- > > Latency: 0 > > Interrupt: pin D routed to IRQ 19 > > Region 0: Memory at fe227000 (32-bit, non-prefetchable) [size=1K] > > Capabilities: [50] Power Management version 2 > > Flags: PMEClk- DSI- D1- D2- AuxCurrent=375mA > > PME(D0+,D1-,D2-,D3hot+,D3cold+) > > Status: D0 PME-Enable- DSel=0 DScale=0 PME+ > > Capabilities: [58] Debug port: BAR=1 offset=00a0 > > Kernel driver in use: ehci_hcd > > Kernel modules: ehci-hcd > > 00: 86 80 36 28 06 01 90 02 03 20 03 0c 00 00 00 00 > > 10: 00 70 22 fe 00 00 00 00 00 00 00 00 00 00 00 00 > > 20: 00 00 00 00 00 00 00 00 00 00 00 00 aa 17 ab 20 > > 30: 00 00 00 00 50 00 00 00 00 00 00 00 0b 04 00 00 > > 40: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 > > 50: 01 58 c2 c9 00 80 00 00 0a 00 a0 20 00 00 00 00 > > 60: 20 20 9f 01 00 00 00 00 01 00 00 01 00 00 08 80 > > 70: c0 00 17 3f 00 00 00 00 00 00 00 00 00 00 00 00 > > 80: 00 00 00 00 01 00 00 00 00 00 00 00 00 00 00 00 > > 90: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 > > a0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 > > b0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 > > c0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 > > d0: 00 00 00 00 00 aa ff 00 00 00 00 00 00 00 00 00 > > e0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 > > f0: 00 00 00 00 88 85 40 00 86 0f 05 00 06 17 02 20 > > > > b. netchip USB debug cable > > http://www.plxtech.com/products/NET2000/NET20DC/default.asp > > > > c. console system: have USB port > > > > 2. SW setting > > a. console system: need to have kernel config > > CONFIG_USB_SERIAL_DEBUG > > you should get /dev/ttyUSBx > > > > # cat /dev/ttyUSBx could get output > > > > b. target system: need to have kernel config > > CONFIG_EARLY_PRINTK_DBGP > > > > boot command line: earlyprintk=dbgp > > > > c. for Nvidia Southbridge based system: kernel will try to probe and > > find out which port has debug device connected. Would be nice to turn this all into a patch that adds this info to Documentation/x86/early-printk.txt or so. Ingo -- 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
