On 1/29 2010 16:00:18 flameman wrote: > > For _this_ kind of magic you have nearly whole 128MB. If you want > to > > stay with kernel 1 boot, then you have 1.6MB. > > umm let me understand this part: do you mean by jtag, just to > shortcut > things directly (jtag download byte directly into flash) ?
No, I mean the kind of magic if you write your own bootloader. You can use NAND backup/restore to work with the whole 128MB. The only area your bootloader probably cannot touch is the device configuration area. I never tried JTAG, but I think that production series of Spitz and Akita are not equipped with the JTAG supporting bridge IC (see the empty soldering pads on the teardown photos). > i am supporting a ppc405GP board which has all the firmware in flash > ... so i had to think about "Recovering a bricked board, using OCD > Jtag programmer" You cannot brick Spitz and Akita. PROM boot should always work. > anybody has ever thought anything similar for akita ? Akita should > have a jtag on his back, and jtag should be directly connected to > PXA270 ... so it should be as standard as a pretty ARM databook > should > explain. No, it is not. There is just a serial IOPORT and few other wires. I am not sure what is the purpose of connector under the battery cover. > what i have not understand is: > 1) is the flash area partitioned with slot0=1.6Mb, > slot1=therest/whatever, and we can't re partion it into a whole 128Mb > slot cause ...cause if we did it than we loose the nandutils&C that > slot1 contains, so we loose a pretty procedure to re-flash if things > go bad ? No. slots are not partitions. Just the first partiton contains slots. There should be: NAND configuration block NAND bootloader slot for kernel 1 slot for kernel 2 (emergency aboot) > 2) could we bypass it, just using jtag ? 1.6Mb is a pain in ... while > i wish i could have 8Mb (or more) to handle a good (and nicer) > bootloader + first aid kit (fsck, badblocks, RTC tools ... etc > etc ... No, only new bootloader could bypass slot1 size. > everything should be pretty useful for a pretty UNIX net install > /maintenance/support) You are not forced to use slot1 kernel as your primary kernel. You can use kexec (e. g. kexecboot) and boot anything you want. > about my kexec-netboot, here is a shot-proof of concept > > (i need this bootloader, cause i net download the first aid kit into > so call "early ram rootfs", also i like this bootloader cause i can > test newkernel easier) No, you don't need custom bootloader. You can learn netboot the kernel in slot1. It would be much less work than programming the bootloader. In fact, I think that nobody wa able to implement custom bootloader yet. There are some proprietary things you would need to reverse-engineer before being able to implement it: - The way how PROM boot passes control to NAND boot. - Completely initialize hardware, including things not initialized in the current kernel (e. g. LCD phase settings). -- Stanislav Brabec http://www.penguin.cz/~utx/zaurus _______________________________________________ Zaurus-devel mailing list Zaurus-devel@lists.linuxtogo.org http://lists.linuxtogo.org/cgi-bin/mailman/listinfo/zaurus-devel
