[LinuxBIOS] [linux-usb-devel] [RFC][PATCH 0/2] x86_64 Early usb debug port support.

Lu, Yinghai yinghai.lu at amd.com
Fri Dec 8 04:48:17 CET 2006

-----Original Message-----
From: linuxbios-bounces at linuxbios.org
[mailto:linuxbios-bounces at linuxbios.org] On Behalf Of
ebiederm at xmission.com

>Ok due to popular demands here is the slightly fixed patch that works
>on both i386 and x86_64.  For the i386 version you must not have
>HIGHMEM64G enabled. 

>I just rolled it all into one patch as I'm to lazy to transmit all
>3 of them.

I got

Firmware type: LinuxBIOS
Linux version 2.6.19-smp-gc9976797-dirty (root at lbsrv) (gcc version
4.0.2) #196 6
Command line: earlyprintk=ttyS0,115200 apic=debug pci=noacpi,routeirq
BIOS-provided physical RAM map:
 BIOS-e820: 0000000000000000 - 0000000000001000 (reserved)
 BIOS-e820: 0000000000001000 - 00000000000a0000 (usable)
 BIOS-e820: 00000000000c0000 - 00000000000f0000 (usable)
 BIOS-e820: 00000000000f0000 - 0000000000100000 (reserved)
 BIOS-e820: 0000000000100000 - 00000000c0000000 (usable)
 BIOS-e820: 0000000100000000 - 0000000240000000 (usable)
dbgp_num: 0
Found EHCI debug port
bar: 10 offset: 098
bar: 10 offset: 098
dbgp pre-set_fixmap_nocache
PANIC: early exception rip ffffffff809c24b4 error 0 cr2 ffff810000203ff8

Call Trace:
 [<ffffffff809c24b4>] __set_fixmap+0x84/0x202
 [<ffffffff809c05bb>] early_dbgp_init+0x259/0x55c
 [<ffffffff8022d958>] __call_console_drivers+0x64/0x72
 [<ffffffff809b242b>] do_early_param+0x0/0x57
 [<ffffffff809c0a20>] setup_early_printk+0x162/0x17e
 [<ffffffff809b2459>] do_early_param+0x2e/0x57
 [<ffffffff8023d051>] parse_args+0x159/0x1f3
 [<ffffffff809b24c2>] parse_early_param+0x40/0x4c
 [<ffffffff809b88ca>] setup_arch+0x1c1/0x636
 [<ffffffff809b2534>] start_kernel+0x55/0x208
 [<ffffffff809b2173>] _sinittext+0x173/0x177

RIP __set_fixmap+0x84/0x202

With Greg's USB Debug, host and target can talk.
target with console=ttyUSB0,115200n8
host with cat /dev/ttyUSB0
But if use minicom in host, it will not show '\r', I guess the usb debug
cable eat return char. Greg, Can you add that back in usb_debug by
replacing '\n' with '\r', '\n'?

With Eric code in LinuxBIOS, it will report "No device found in debug


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