[U-Boot] NAND on mpc8360erdk

I am in the middle of NAND debugging on a MPC8544 based system.

In the following code for the mpc8360erdk, why is there the instruction "out_8(upm->io_addr, 0x0);" in the for loop. Is that board specific?

static void upm_setup(struct fsl_upm *upm) { int i;

/* write upm array */ out_be32(upm->mxmr, MxMR_OP_WARR);

for (i = 0; i < 64; i++) { out_be32(upm->mdr, upm_array[i]); out_8(upm->io_addr, 0x0); }

/* normal operation */ out_be32(upm->mxmr, MxMR_OP_NORM); while (in_be32(upm->mxmr) != MxMR_OP_NORM) eieio(); }