static struct unipro_xfer_descriptor *pick_tx_descriptor(void)
{
struct unipro_xfer_descriptor *desc;
int i;
for (i = 0; i < unipro_cport_count(); i++) {
struct cport *cport = cport_handle(i);
if (!cport)
continue;
if (list_is_empty(&cport->tx_fifo))
continue;
desc = containerof(cport->tx_fifo.next, struct unipro_xfer_descriptor,
list);
if (desc->channel)
continue;
if (!unipro_get_tx_free_buffer_space(desc->cport))
continue;
return desc;
}
return NULL;
}
/**
* @brief Send data down to a CPort
* @return number of bytes effectively sent (>= 0), or error code (< 0)
* @param[in] cportid: cport to send down
* @param[in] buf: data buffer
* @param[in] len: size of data to send
* @param[in] som: "start of message" flag
*/
static int unipro_send_sync(unsigned int cportid,
const void *buf, size_t len, bool som)
{
struct cport *cport;
uint16_t count;
uint8_t *tx_buf;
if (len > CPORT_BUF_SIZE) {
return -EINVAL;
}
cport = cport_handle(cportid);
if (!cport) {
return -EINVAL;
}
if (!cport->connected) {
lldbg("CP%d unconnected\n", cport->cportid);
return -EPIPE;
}
DEBUGASSERT(TRANSFER_MODE == 2);
/*
* If this is not the start of a new message,
* message data must be written to first address of CPort Tx Buffer + 1.
*/
if (!som) {
tx_buf = cport->tx_buf + sizeof(uint32_t);
} else {
tx_buf = cport->tx_buf;
}
count = unipro_get_tx_free_buffer_space(cport);
if (!count) {
/* No free space in TX FIFO, cannot send anything. */
DBG_UNIPRO("No free space in CP%d Tx Buffer\n", cportid);
return 0;
} else if (count > len) {
count = len;
}
/* Copy message data in CPort Tx FIFO */
DBG_UNIPRO("Sending %u bytes to CP%d\n", count, cportid);
memcpy(tx_buf, buf, count);
return (int) count;
}
static int unipro_continue_xfer(struct unipro_xfer_descriptor *desc)
{
size_t xfer_len;
desc->remaining_xfer_len -= desc->dma_arg.unipro_tx_arg.next_transfer_len;
xfer_len = unipro_get_tx_free_buffer_space(desc->cport);
if (!xfer_len)
return -ENOSPC;
xfer_len = MIN(desc->remaining_xfer_len, xfer_len);
desc->dma_arg.unipro_tx_arg.next_transfer_len = xfer_len;
if (xfer_len == desc->remaining_xfer_len)
desc->dma_arg.unipro_tx_arg.eom_addr = CPORT_EOM_BIT(desc->cport);
return 0;
}
static int unipro_dma_xfer(struct unipro_xfer_descriptor *desc,
struct dma_channel *channel)
{
int retval;
size_t xfer_len;
void *cport_buf;
void *xfer_buf;
xfer_len = unipro_get_tx_free_buffer_space(desc->cport);
if (!xfer_len)
return -ENOSPC;
xfer_len = MIN(desc->remaining_xfer_len, xfer_len);
desc->channel = channel;
desc->dma_arg.unipro_tx_arg.next_transfer_len = xfer_len;
if (xfer_len == desc->remaining_xfer_len)
desc->dma_arg.unipro_tx_arg.eom_addr = CPORT_EOM_BIT(desc->cport);
DBG_UNIPRO("xfer: chan=%u, len=%zu\n", channel->id, xfer_len);
cport_buf = desc->cport->tx_buf;
xfer_buf = (void*) desc->data;
/* resuming a paused xfer */
if (desc->remaining_xfer_len != desc->len) {
cport_buf = (char*) cport_buf + 1; /* skip the start byte */
/* move buffer offset to the beginning of the remaning bytes to xfer */
xfer_buf = (char*) xfer_buf + (desc->len - desc->remaining_xfer_len);
}
retval = device_dma_transfer(unipro_dma.dev, channel->id, xfer_buf,
cport_buf, xfer_len, &desc->dma_arg);
if (retval) {
lowsyslog("unipro: failed to start DMA transfer: %d\n", retval);
return retval;
}
return 0;
}
static struct unipro_xfer_descriptor *pick_tx_descriptor(unsigned int cportid)
{
struct unipro_xfer_descriptor *desc;
unsigned int cport_count = unipro_cport_count();
int i;
for (i = 0; i < cport_count; i++, cportid++) {
struct cport *cport;
cportid = cportid % cport_count;
cport = cport_handle(cportid);
if (!cport)
continue;
if (list_is_empty(&cport->tx_fifo)) {
if (cport->pending_reset) {
unipro_flush_cport(cport);
}
continue;
}
if (cport->pending_reset) {
unipro_flush_cport(cport);
}
desc = containerof(cport->tx_fifo.next, struct unipro_xfer_descriptor,
list);
if (desc->channel)
continue;
if (!unipro_get_tx_free_buffer_space(desc->cport))
continue;
return desc;
}
return NULL;
}
static int unipro_dma_xfer(struct unipro_xfer_descriptor *desc,
struct dma_channel *channel)
{
int retval;
size_t xfer_len;
void *cport_buf;
void *xfer_buf;
struct device_dma_op *dma_op = NULL;
if (tsb_get_rev_id() == tsb_rev_es2) {
xfer_len = unipro_get_tx_free_buffer_space(desc->cport);
if (!xfer_len)
return -ENOSPC;
xfer_len = MIN(desc->len - desc->data_offset, xfer_len);
} else {
DEBUGASSERT(desc->data_offset == 0);
xfer_len = desc->len;
}
desc->channel = channel;
retval = device_dma_op_alloc(unipro_dma.dev, 1, 0, &dma_op);
if (retval != OK) {
lowsyslog("unipro: failed allocate a DMA op, retval = %d.\n", retval);
return retval;
}
dma_op->callback = (void *) unipro_dma_tx_callback;
dma_op->callback_arg = desc;
dma_op->callback_events = DEVICE_DMA_CALLBACK_EVENT_COMPLETE;
if (tsb_get_rev_id() != tsb_rev_es2) {
dma_op->callback_events |= DEVICE_DMA_CALLBACK_EVENT_START;
}
dma_op->sg_count = 1;
dma_op->sg[0].len = xfer_len;
DBG_UNIPRO("xfer: chan=%u, len=%zu\n", channel->id, xfer_len);
cport_buf = desc->cport->tx_buf;
xfer_buf = (void*) desc->data;
/* resuming a paused xfer */
if (desc->data_offset != 0) {
cport_buf = (char*) cport_buf + sizeof(uint64_t); /* skip the first DWORD */
/* move buffer offset to the beginning of the remaning bytes to xfer */
xfer_buf = (char*) xfer_buf + desc->data_offset;
}
dma_op->sg[0].src_addr = (off_t) xfer_buf;
dma_op->sg[0].dst_addr = (off_t) cport_buf;
desc->data_offset += xfer_len;
retval = device_dma_enqueue(unipro_dma.dev, channel->chan, dma_op);
if (retval) {
lowsyslog("unipro: failed to start DMA transfer: %d\n", retval);
return retval;
}
return 0;
}
