static Cyg_ErrNo altera_avalon_jtag_uart_set_config(serial_channel *chan,
cyg_uint32 key,
const void *xbuf,
cyg_uint32 *len)
{
altera_avalon_jtag_uart_dev *jtag_uart_chan =
(altera_avalon_jtag_uart_dev *)chan->dev_priv;
cyg_addrword_t port = jtag_uart_chan->base;
Cyg_ErrNo ret_code;
cyg_uint32 control;
switch (key)
{
case CYG_IO_SET_CONFIG_SERIAL_HW_RX_FLOW_THROTTLE:
{
if(*len != 4)
{
ret_code = -EINVAL;
}
else
{
if (*(char*)xbuf == 1)
{
/*
* Throttle Rx
*/
control = IORD_ALTERA_AVALON_JTAG_UART_CONTROL(port);
control &= ~ALTERA_AVALON_JTAG_UART_CONTROL_RE_MSK;
IOWR_ALTERA_AVALON_JTAG_UART_CONTROL(port, control);
ret_code = ENOERR;
}
else if (*(char*)xbuf == 0)
{
/*
* Restart Rx
*/
control = IORD_ALTERA_AVALON_JTAG_UART_CONTROL(port);
control |= ALTERA_AVALON_JTAG_UART_CONTROL_RE_MSK;
IOWR_ALTERA_AVALON_JTAG_UART_CONTROL(port, control);
ret_code = ENOERR;
}
else
{
ret_code = -EINVAL;
}
}
break;
}
default:
{
ret_code = -EINVAL;
break;
}
}
return ret_code;
}
static void altera_avalon_jtag_uart_stop_xmit(serial_channel *chan)
{
altera_avalon_jtag_uart_dev *jtag_uart_chan =
(altera_avalon_jtag_uart_dev *)chan->dev_priv;
cyg_addrword_t port = jtag_uart_chan->base;
cyg_uint32 control;
unsigned int status;
control = IORD_ALTERA_AVALON_JTAG_UART_CONTROL(port);
control &= ~ALTERA_AVALON_JTAG_UART_CONTROL_WE_MSK;
IOWR_ALTERA_AVALON_JTAG_UART_CONTROL(port, control);
return;
}
//-------------------------------------------------------------------------------
int alt_avn_jtag_uart_read(alt_avn_jtag_uart_state* sp,
char * buffer, int space, int flags)
{
char * ptr = buffer;
alt_irq_context context;
unsigned int n;
/*
* When running in a multi threaded environment, obtain the "read_lock"
* semaphore. This ensures that reading from the device is thread-safe.
*/
ALT_SEM_PEND (sp->read_lock, 0);
while (space > 0)
{
unsigned int in, out;
/* Read as much data as possible */
do
{
in = sp->rx_in;
out = sp->rx_out;
if (in >= out)
n = in - out;
else
n = ALTERA_AVALON_JTAG_UART_BUF_LEN - out;
if (n == 0)
break; /* No more data available */
if (n > space)
n = space;
memcpy(ptr, sp->rx_buf + out, n);
ptr += n;
space -= n;
sp->rx_out = (out + n) % ALTERA_AVALON_JTAG_UART_BUF_LEN;
}
while (space > 0);
/* If we read any data then return it */
if (ptr != buffer)
break;
/* If in non-blocking mode then return error */
if (flags & O_NONBLOCK)
break;
/* OS Present: Pend on a flag if the OS is running, otherwise spin */
if(OSRunning == OS_TRUE) {
/*
* When running in a multi-threaded mode, we pend on the read event
* flag set and timeout event flag set in the isr. This avoids wasting CPU
* cycles waiting in this thread, when we could be doing something more
* profitable elsewhere.
*/
ALT_FLAG_PEND (sp->events,
ALT_JTAG_UART_READ_RDY | ALT_JTAG_UART_TIMEOUT,
OS_FLAG_WAIT_SET_ANY + OS_FLAG_CONSUME,
0);
}
else {
/* Spin until more data arrives or until host disconnects */
while (in == sp->rx_in && sp->host_inactive < sp->timeout)
;
}
if (in == sp->rx_in)
break;
}
/*
* Now that access to the circular buffer is complete, release the read
* semaphore so that other threads can access the buffer.
*/
ALT_SEM_POST (sp->read_lock);
if (ptr != buffer)
{
/* If we read any data then there is space in the buffer so enable interrupts */
context = alt_irq_disable_all();
sp->irq_enable |= ALTERA_AVALON_JTAG_UART_CONTROL_RE_MSK;
IOWR_ALTERA_AVALON_JTAG_UART_CONTROL(sp->base, sp->irq_enable);
alt_irq_enable_all(context);
}
if (ptr != buffer)
return ptr - buffer;
else if (flags & O_NONBLOCK)
return -EWOULDBLOCK;
else
return -EIO;
}
int alt_avn_jtag_uart_write(alt_avn_jtag_uart_state* sp,
const char * ptr, int count, int flags)
{
/* Remove warning at optimisation level 03 by seting out to 0 */
unsigned int in, out=0;
unsigned int n;
alt_irq_context context;
const char * start = ptr;
/*
* When running in a multi threaded environment, obtain the "write_lock"
* semaphore. This ensures that writing to the device is thread-safe.
*/
ALT_SEM_PEND (sp->write_lock, 0);
do
{
/* Copy as much as we can into the transmit buffer */
while (count > 0)
{
/* We need a stable value of the out pointer to calculate the space available */
in = sp->tx_in;
out = sp->tx_out;
if (in < out)
n = out - 1 - in;
else if (out > 0)
n = ALTERA_AVALON_JTAG_UART_BUF_LEN - in;
else
n = ALTERA_AVALON_JTAG_UART_BUF_LEN - 1 - in;
if (n == 0)
break;
if (n > count)
n = count;
memcpy(sp->tx_buf + in, ptr, n);
ptr += n;
count -= n;
sp->tx_in = (in + n) % ALTERA_AVALON_JTAG_UART_BUF_LEN;
}
/*
* If interrupts are disabled then we could transmit here, we only need
* to enable interrupts if there is no space left in the FIFO
*
* For now kick the interrupt routine every time to make it transmit
* the data
*/
context = alt_irq_disable_all();
sp->irq_enable |= ALTERA_AVALON_JTAG_UART_CONTROL_WE_MSK;
IOWR_ALTERA_AVALON_JTAG_UART_CONTROL(sp->base, sp->irq_enable);
alt_irq_enable_all(context);
/*
* If there is any data left then either return now or block until
* some has been sent
*/
/* consider: test whether there is anything there while doing this and delay for at most 2s. */
if (count > 0)
{
if (flags & O_NONBLOCK)
break;
/* OS Present: Pend on a flag if the OS is running, otherwise spin */
if(OSRunning == OS_TRUE) {
/*
* When running in a multi-threaded mode, we pend on the write event
* flag set or the timeout flag in the isr. This avoids wasting CPU
* cycles waiting in this thread, when we could be doing something
* more profitable elsewhere.
*/
ALT_FLAG_PEND (sp->events,
ALT_JTAG_UART_WRITE_RDY | ALT_JTAG_UART_TIMEOUT,
OS_FLAG_WAIT_SET_ANY + OS_FLAG_CONSUME,
0);
}
else {
/*
* OS not running: Wait for data to be removed from buffer.
* Once the interrupt routine has removed some data then we
* will be able to insert some more.
*/
while (out == sp->tx_out && sp->host_inactive < sp->timeout)
;
}
if (out == sp->tx_out)
break;
}
}
while (count > 0);
/*
* Now that access to the circular buffer is complete, release the write
* semaphore so that other threads can access the buffer.
*/
ALT_SEM_POST (sp->write_lock);
if (ptr != start)
return ptr - start;
else if (flags & O_NONBLOCK)
return -EWOULDBLOCK;
else
return -EIO; /* Host not connected */
}
