#!/bin/rc
rfork n

fn fatal{
	echo >[1=2] $*
	exit fatal
}

fn verbose{
	if(~ $#flagv 1)
		echo >[1=2] $*
}

bind -b '#F' /dev	|| fatal cant bind flash device
cd /dev/flash	|| fatal cant cd to /dev/flash

erasesz=`{awk 'NR==2 {sub(/0x0+/, "", $3); print $3}' < flashctl}
totsz=4m	# 4mb; adjust to taste
plan9ini=`{pxeof $sysname}
kernel=`{ndb/query sys $sysname bootf}

flagfmt='v,I,W,K,i plan9ini,k kernel,e erasesz,t totsz'
args=''
if(! ifs=() eval `{aux/getflags $*}){
	aux/usage
	exit usage
}

erasesz	=`{aux/number -f %x $erasesz}	|| exits num
totsz	=`{aux/number -f %x $totsz}	|| exits num
blsz=$erasesz

eraseblocks=`{echo '
	16i 10o
	' $erasesz ' sa
	' $totsz ' sb

	lb la 1 - + la / 2+
	sn 0si

	[100000 la li *+p li 1 + si li ln >y]sy
	lyx
	' | dc}
kblk=`{echo $#eraseblocks 2 - p | dc}

if(! test -f $plan9ini>[2=]){
	echo >[1=2] plan9.ini $plan9ini not found
	exit check
}
if(! test -f $kernel>[2=]){
	echo >[1=2] kernel $kernel not found
	exit check
}
if(~ $#eraseblocks 0 || ~ $"eraseblocks *unimplemented* || test $#eraseblocks -gt 64){
	echo >[1=2] wierd number of pages to clear $#pages
	exit check
}

if(~ $#flagW^$#flagI^$#flagK 000 111){
	flagW=1; flagI=1; flagK=1
}
if not{
	e=()
	if(~ $#flagW 1)
		e = ($e $eraseblocks(1)
	if(~ $#flagI 1)
		e = ($e $eraseblocks(2)
	if(~ $#flagK 1)
		e = ($e $eraseblocks(3-)
}

echo erasing $#eraseblocks `{echo 16i $erasesz 400 / p | dc}^k blocks
verbose eraseblocks $eraseblocks

for(i in $eraseblocks){
	verbose erase 0x$i
	if(! echo erase 0x$i > flashctl){
		echo kwflashprep: erase block 0x$i
		exit erase
	}
}

fn kfill {
	cat $kernel /dev/zero | dd -quiet 1 -conv sync -bs 8192
}
fn α {
	echo 16 i 10 o $1 $erasesz $2 '*' + p | dc
}
x=`{echo $kblk sk 16i $erasesz 2000 / lk '*' p|dc}

~ $#flagW 1	&& {auth/wrkey || exit wrkey}
~ $#flagI 1	&& {dd -of flash -oseek  9 -count 1	-if $plan9ini	-bs 0x$erasesz -conv sync	|| exit ddini}
~ $#flagK 1	&& {dd -of flash -oseek 10 -count $x	-if <{kfill}	-obs 0x$erasesz -ibs 8192	|| exit ddkern}


# double check for ecc errors
dd -if flash -iseek 8 -count $#eraseblocks -bs 0x$erasesz >/dev/null || exit ecc errors

echo setenv bootcmd \
	''''nand read 0x1000 0x`{α 100000 1} '0x200;' \
	nand read 0x800000 0x`{α 100000 2} '0x300000;' go 0x800000''''

{
echo add nvram		0x`{α 100000 0} 0x`{α 100000 1}
echo add plan9.ini	0x`{α 100000 1} 0x`{α 100000 2}
echo add kernel		0x`{α 100000 2} 0x`{echo 16i 10o $totsz $erasesz 2 '*' - 100000 + p|dc}
}>flashctl

# nvram 	0x00100000 0x00120000 0x00020000 0x00000800
# plan9.ini 	0x00120000 0x00140000 0x00020000 0x00000800
# kernel 	0x00140000 0x004c0000 0x00020000 0x00000800