In include/commproc.h CPM_I2C_BASE is set to 0x820 and CPM_SPI_BASE is set 0x840, but 
in cpu/mpc8xx/i2c.c 4 TX and 4 RX i2c buffers (each of 8 bytes) are declared.
I believe this causes a problem when issueing an SPI command after and I2C one.
Someone can confirm that this could be a problem?

Bye,
Antonio.