+ do {
+ p = &rx_desc_base[rx_desc_index * 8];
+
+ INVALIDATE_DCACHE (&p[0], &p[1]);
+ /* Wait for character */
+ while (p[1] & DESC_OWNER) {
+ udelay (100);
+ INVALIDATE_DCACHE (&p[0], &p[1]);
+ }
+
+ /* Handle error case */
+ if (p[1] & (1 << 15)) {
+ printf ("oops, error: %08x\n", p[1]);
+
+ temp = GTREGREAD_MIRROR (GALMPSC_CHANNELREG_2,
+ CHANNEL, GALMPSC_REG_GAP);
+ temp |= (1 << 23);
+ GT_REG_WRITE_MIRROR (GALMPSC_CHANNELREG_2, CHANNEL,
+ GALMPSC_REG_GAP, temp);
+
+ /* Can't poll on abort bit, so we just wait. */
+ udelay (100);
+
+ galsdma_enable_rx ();
+ }
+
+ /* Number of bytes left in this descriptor */
+ len = p[0] & 0xffff;
+
+ if (len) {
+ /* Where to look */
+ idx = 5;
+ if (done > 3)
+ idx = 4;
+ if (done > 7)
+ idx = 7;
+ if (done > 11)
+ idx = 6;
+
+ INVALIDATE_DCACHE (&p[idx], &p[idx + 1]);
+ ch = p[idx] & 0xff;
+ done++;
+ }
+
+ if (done < len) {
+ /* this descriptor has more bytes still
+ * shift down the char we just read, and leave the
+ * buffer in place for the next time around
+ */
+ p[idx] = p[idx] >> 8;
+ FLUSH_DCACHE (&p[idx], &p[idx + 1]);
+ }
+
+ if (done == len) {
+ /* nothing left in this descriptor.
+ * go to next one
+ */
+ p[1] = DESC_OWNER | DESC_FIRST | DESC_LAST;
+ p[0] = 0x00100000;
+ FLUSH_DCACHE (&p[0], &p[1]);
+ /* Next descriptor */
+ rx_desc_index = (rx_desc_index + 1) % RX_DESC;
+ done = 0;
+ }
+ } while (len == 0); /* galileo bug.. len might be zero */
+
+ return ch;