PDC_BYTE_COUNT
bccrl = ioread32(mmio_base + PDC_BYTE_COUNT) & 0x7fff;
bccrh = ioread32(mmio_base + PDC_BYTE_COUNT + 0x100) & 0x7fff;
bccrlv = ioread32(mmio_base + PDC_BYTE_COUNT) & 0x7fff;
bccrhv = ioread32(mmio_base + PDC_BYTE_COUNT + 0x100) & 0x7fff;