On Sun, Oct 17, 2010 at 08:23:57PM -0500, Scott Duplichan wrote:
]> For coreboot+seabios, I get a power on to DOS boot time of around 2.7 ]> seconds. This is with USB enabled and a 5400 rpm sata drive. While 2.7 ]> seconds is good, there is probably room for improvement. I would like ]> to see a bigger coreboot advantage over UEFI. All of these numbers are ]> for AMD hardware with family 10h processors. ] ]Thanks. Can you post the debug output using SeaBIOS' ]tools/readserial.py program? I'd be curious to see where the time is ]spent. ] ]Also, try the SeaBIOS options CONFIG_THREAD_OPTIONROMS and ]CONFIG_ATA_DMA. (The ATA DMA can be a little finicky though - fixing ]it is on my todo list.)
I am not sure how to get that script to run from windows. I get:
$ python ../seabios-for-coreboot/tools/readserial.py com1 115200 Traceback (most recent call last): File "../seabios-for-coreboot/tools/readserial.py", line 129, in <module> main() File "../seabios-for-coreboot/tools/readserial.py", line 114, in main import serial ImportError: No module named serial
Thanks for the report. You need the pyserial package - see: http://pyserial.sourceforge.net/
I've updated the script to make this more descriptive.
But it hardly matters. I think coreboot is taking most of the time. For example, I noticed a hesitation at: "copying VGA ROM Image from %p to 0x%x, 0x%x bytes\n"
It's best to let SeaBIOS run the rom - try setting CONFIG_VGA_ROM_RUN and CONFIG_PCI_ROM_RUN to off in coreboot. Also, set CONFIG_DRIVERS_PS2_KEYBOARD off as well.
[...]
With these two changes, boot time is reduced by 650 ms. Now the boot time is around 2.050 seconds. That is from power switch off (standby power on) to DOS prompt.
[...]
By the way, I tried your other suggestions and did not see much of a difference. I do need to get an SSD drive because the randomness in the rotating drive makes precise measurements difficult. The DMA hardly matters for DOS where only a few KB are read from disk. But it could be very important for OS booting, where as much as hundreds of MB are read from disk using BIOS calls.
Yeah - I found the SSD to be a big win on boot times - simply because it eliminated the spin-up delay. I also tried USB drives and a compact flash card with an ATA/SATA adapter, but all three exhibited "spin-up" delays.
-Kevin