Hi,
I have defined a section name ".isrsec" and then a function "extint_isr()" is placed into that section by using following:

extern void extint_isr() __attribute__ ((section (".isrsec")));

With this, the .lst file showing the extint_isr function at the address specified at .isrsec section, which is fine.

Now, can we call a function, say wr(addr, data) which is by default placed in .text section in extint_isr function ??

If I do so, below is my observation:
In .lst file, at calling of wr function has the jump to current section addr + actual wr function offset.
ex :
// .text sec
wr() { } is @ 0x1478

//.isrsec sec
extint_isr { @ 0xf0000f5c
....
wr() // l.jal 0xf0001478
}

But I want the l.jal should be 0x1478.

Thanks,
Kranti

any help in this regard ?

The instruction you actually want is something like l.jal 0x04000147 (0x0400_0147 sll 2 = 0x1000_051C, then 0xF000_0F5C + 0x0x1000_051C = 0x00001478). Note that I got this by looking at the instruction in the OR1200 architecture reference manual. The manual also reports that the space reserved for the immediate is 26 bits, but the length of your jump requires an immediate of 27 bits. So the instruction l.jal 0x04000147 is trimmed to l.jal 0x147 which produces a jump to 0xF000_1478. Even if the field for the immediate was 27-bits, you would have a problem as the immediate is sign extended.