Ethernet CPDMA

Hi,

 in AM335x TRM, session 14.3.2.4.1 CCPI Buffer Descriptors, the Note mention that CPPI RAM begin at address 0x4a102000 and end at 0x4a103FFF.

but when i print the value "&(prev->hw_mode)" in u-boot, it shown 0x8ff77204, which is exceed the range of CPPI RAM as mention above.

is this normal ?

in file "board-support/u-boot-2011.09-psp04.06.00.02/driver/net/cpsw.c":

static int cpdma_submit(struct cpsw_priv *priv, struct cpdma_chan *chan,
   volatile void *buffer, int len)
{
 struct cpdma_desc *desc, *prev;
 u32 mode;

 desc = cpdma_desc_alloc(priv);
 if (!desc)
  return -ENOMEM;

 if (len < PKT_MIN)
  len = PKT_MIN;

 mode = CPDMA_DESC_OWNER | CPDMA_DESC_SOP | CPDMA_DESC_EOP;

 desc_write(desc, hw_next,   0);
 desc_write(desc, hw_buffer, buffer);
 desc_write(desc, hw_len,    len);
 desc_write(desc, hw_mode,   mode | len);
 desc_write(desc, sw_buffer, buffer);
 desc_write(desc, sw_len,    len);

 if (!chan->head) {
  /* simple case - first packet enqueued */
  chan->head = desc;
  chan->tail = desc;
  chan_write(chan, hdp, desc);
  goto done;
 }

 /* not the first packet - enqueue at the tail */
 prev = chan->tail;
 desc_write(prev, hw_next, desc);
 chan->tail = desc;

 /* next check if EOQ has been triggered already */
printf("Checking address [0x%08x] value is [0x%08x]\n",&(prev->hw_mode),desc_read(prev, hw_mode)); -----------------added by me
 if (desc_read(prev, hw_mode) & CPDMA_DESC_EOQ)
  chan_write(chan, hdp, desc);

done:
 if (chan->rxfree)
  chan_write(chan, rxfree, 1);
 return 0;
}

When i enter the "dhcp" command in U-Boot:

U-boot#dhcp

Checking address [0x8ff77204] value is [0xe00005ee]                            
Checking address [0x8ff7721c] value is [0xe00005ee]                            
Checking address [0x8ff77234] value is [0xe00005ee]                            
BOOTP broadcast 1                                                              
BOOTP broadcast 2                                                              
BOOTP broadcast 3                                                              
BOOTP broadcast 4

Thanks & Regards

Keldy