Example #1
0
static irqreturn_t bfin_serial_dma_rx_int(int irq, void *dev_id)
{
	struct bfin_serial_port *uart = dev_id;
	unsigned short irqstat;
	int x_pos, pos;

	spin_lock(&uart->rx_lock);
	irqstat = get_dma_curr_irqstat(uart->rx_dma_channel);
	clear_dma_irqstat(uart->rx_dma_channel);

	uart->rx_dma_nrows = get_dma_curr_ycount(uart->rx_dma_channel);
	x_pos = get_dma_curr_xcount(uart->rx_dma_channel);
	uart->rx_dma_nrows = DMA_RX_YCOUNT - uart->rx_dma_nrows;
	if (uart->rx_dma_nrows == DMA_RX_YCOUNT || x_pos == 0)
		uart->rx_dma_nrows = 0;

	pos = uart->rx_dma_nrows * DMA_RX_XCOUNT;
	if (pos > uart->rx_dma_buf.tail ||
		uart->rx_dma_nrows < (uart->rx_dma_buf.tail/DMA_RX_XCOUNT)) {
		uart->rx_dma_buf.head = pos;
		bfin_serial_dma_rx_chars(uart);
		uart->rx_dma_buf.tail = uart->rx_dma_buf.head;
	}

	spin_unlock(&uart->rx_lock);

	return IRQ_HANDLED;
}
Example #2
0
static irqreturn_t bfin_serial_dma_rx_int(int irq, void *dev_id)
{
	struct bfin_serial_port *uart = dev_id;
	unsigned short irqstat;

	spin_lock(&uart->port.lock);
	irqstat = get_dma_curr_irqstat(uart->rx_dma_channel);
	clear_dma_irqstat(uart->rx_dma_channel);
	bfin_serial_dma_rx_chars(uart);
	spin_unlock(&uart->port.lock);

	return IRQ_HANDLED;
}
Example #3
0
static void bfin_serial_rx_chars(struct bfin_serial_port *uart)
{
	struct tty_struct *tty = NULL;
	unsigned int status, ch, flg;
	static struct timeval anomaly_start = { .tv_sec = 0 };

	status = UART_GET_LSR(uart);
	UART_CLEAR_LSR(uart);

 	ch = UART_GET_CHAR(uart);
 	uart->port.icount.rx++;

#if defined(CONFIG_KGDB_SERIAL_CONSOLE) || \
	defined(CONFIG_KGDB_SERIAL_CONSOLE_MODULE)
	if (kgdb_connected && kgdboc_port_line == uart->port.line)
		if (ch == 0x3) {/* Ctrl + C */
			kgdb_breakpoint();
			return;
		}

	if (!uart->port.info || !uart->port.info->tty)
		return;
#endif
	tty = uart->port.info->tty;

	if (ANOMALY_05000363) {
		/* The BF533 (and BF561) family of processors have a nice anomaly
		 * where they continuously generate characters for a "single" break.
		 * We have to basically ignore this flood until the "next" valid
		 * character comes across.  Due to the nature of the flood, it is
		 * not possible to reliably catch bytes that are sent too quickly
		 * after this break.  So application code talking to the Blackfin
		 * which sends a break signal must allow at least 1.5 character
		 * times after the end of the break for things to stabilize.  This
		 * timeout was picked as it must absolutely be larger than 1
		 * character time +/- some percent.  So 1.5 sounds good.  All other
		 * Blackfin families operate properly.  Woo.
		 */
		if (anomaly_start.tv_sec) {
			struct timeval curr;
			suseconds_t usecs;

			if ((~ch & (~ch + 1)) & 0xff)
				goto known_good_char;

			do_gettimeofday(&curr);
			if (curr.tv_sec - anomaly_start.tv_sec > 1)
				goto known_good_char;

			usecs = 0;
			if (curr.tv_sec != anomaly_start.tv_sec)
				usecs += USEC_PER_SEC;
			usecs += curr.tv_usec - anomaly_start.tv_usec;

			if (usecs > UART_GET_ANOMALY_THRESHOLD(uart))
				goto known_good_char;

			if (ch)
				anomaly_start.tv_sec = 0;
			else
				anomaly_start = curr;

			return;

 known_good_char:
			status &= ~BI;
			anomaly_start.tv_sec = 0;
		}
	}

	if (status & BI) {
		if (ANOMALY_05000363)
			if (bfin_revid() < 5)
				do_gettimeofday(&anomaly_start);
		uart->port.icount.brk++;
		if (uart_handle_break(&uart->port))
			goto ignore_char;
		status &= ~(PE | FE);
	}
	if (status & PE)
		uart->port.icount.parity++;
	if (status & OE)
		uart->port.icount.overrun++;
	if (status & FE)
		uart->port.icount.frame++;

	status &= uart->port.read_status_mask;

	if (status & BI)
		flg = TTY_BREAK;
	else if (status & PE)
		flg = TTY_PARITY;
	else if (status & FE)
		flg = TTY_FRAME;
	else
		flg = TTY_NORMAL;

	if (uart_handle_sysrq_char(&uart->port, ch))
		goto ignore_char;

	uart_insert_char(&uart->port, status, OE, ch, flg);

 ignore_char:
	tty_flip_buffer_push(tty);
}

static void bfin_serial_tx_chars(struct bfin_serial_port *uart)
{
	struct circ_buf *xmit = &uart->port.info->xmit;

	/*
	 * Check the modem control lines before
	 * transmitting anything.
	 */
	bfin_serial_mctrl_check(uart);

	if (uart_circ_empty(xmit) || uart_tx_stopped(&uart->port)) {
#ifdef CONFIG_BF54x
		/* Clear TFI bit */
		UART_PUT_LSR(uart, TFI);
#endif
		UART_CLEAR_IER(uart, ETBEI);
		return;
	}

	if (uart->port.x_char) {
		UART_PUT_CHAR(uart, uart->port.x_char);
		uart->port.icount.tx++;
		uart->port.x_char = 0;
	}

	while ((UART_GET_LSR(uart) & THRE) && xmit->tail != xmit->head) {
		UART_PUT_CHAR(uart, xmit->buf[xmit->tail]);
		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
		uart->port.icount.tx++;
		SSYNC();
	}

	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
		uart_write_wakeup(&uart->port);
}

static irqreturn_t bfin_serial_rx_int(int irq, void *dev_id)
{
	struct bfin_serial_port *uart = dev_id;

	spin_lock(&uart->port.lock);
	while (UART_GET_LSR(uart) & DR)
		bfin_serial_rx_chars(uart);
	spin_unlock(&uart->port.lock);

	return IRQ_HANDLED;
}

static irqreturn_t bfin_serial_tx_int(int irq, void *dev_id)
{
	struct bfin_serial_port *uart = dev_id;

	spin_lock(&uart->port.lock);
	if (UART_GET_LSR(uart) & THRE)
		bfin_serial_tx_chars(uart);
	spin_unlock(&uart->port.lock);

	return IRQ_HANDLED;
}
#endif

#ifdef CONFIG_SERIAL_BFIN_DMA
static void bfin_serial_dma_tx_chars(struct bfin_serial_port *uart)
{
	struct circ_buf *xmit = &uart->port.info->xmit;

	uart->tx_done = 0;

	/*
	 * Check the modem control lines before
	 * transmitting anything.
	 */
	bfin_serial_mctrl_check(uart);

	if (uart_circ_empty(xmit) || uart_tx_stopped(&uart->port)) {
		uart->tx_count = 0;
		uart->tx_done = 1;
		return;
	}

	if (uart->port.x_char) {
		UART_PUT_CHAR(uart, uart->port.x_char);
		uart->port.icount.tx++;
		uart->port.x_char = 0;
	}

	uart->tx_count = CIRC_CNT(xmit->head, xmit->tail, UART_XMIT_SIZE);
	if (uart->tx_count > (UART_XMIT_SIZE - xmit->tail))
		uart->tx_count = UART_XMIT_SIZE - xmit->tail;
	blackfin_dcache_flush_range((unsigned long)(xmit->buf+xmit->tail),
					(unsigned long)(xmit->buf+xmit->tail+uart->tx_count));
	set_dma_config(uart->tx_dma_channel,
		set_bfin_dma_config(DIR_READ, DMA_FLOW_STOP,
			INTR_ON_BUF,
			DIMENSION_LINEAR,
			DATA_SIZE_8,
			DMA_SYNC_RESTART));
	set_dma_start_addr(uart->tx_dma_channel, (unsigned long)(xmit->buf+xmit->tail));
	set_dma_x_count(uart->tx_dma_channel, uart->tx_count);
	set_dma_x_modify(uart->tx_dma_channel, 1);
	enable_dma(uart->tx_dma_channel);

	UART_SET_IER(uart, ETBEI);
}

static void bfin_serial_dma_rx_chars(struct bfin_serial_port *uart)
{
	struct tty_struct *tty = uart->port.info->port.tty;
	int i, flg, status;

	status = UART_GET_LSR(uart);
	UART_CLEAR_LSR(uart);

	uart->port.icount.rx +=
		CIRC_CNT(uart->rx_dma_buf.head, uart->rx_dma_buf.tail,
		UART_XMIT_SIZE);

	if (status & BI) {
		uart->port.icount.brk++;
		if (uart_handle_break(&uart->port))
			goto dma_ignore_char;
		status &= ~(PE | FE);
	}
	if (status & PE)
		uart->port.icount.parity++;
	if (status & OE)
		uart->port.icount.overrun++;
	if (status & FE)
		uart->port.icount.frame++;

	status &= uart->port.read_status_mask;

	if (status & BI)
		flg = TTY_BREAK;
	else if (status & PE)
		flg = TTY_PARITY;
	else if (status & FE)
		flg = TTY_FRAME;
	else
		flg = TTY_NORMAL;

	for (i = uart->rx_dma_buf.tail; i != uart->rx_dma_buf.head; i++) {
		if (i >= UART_XMIT_SIZE)
			i = 0;
		if (!uart_handle_sysrq_char(&uart->port, uart->rx_dma_buf.buf[i]))
			uart_insert_char(&uart->port, status, OE,
				uart->rx_dma_buf.buf[i], flg);
	}

 dma_ignore_char:
	tty_flip_buffer_push(tty);
}

void bfin_serial_rx_dma_timeout(struct bfin_serial_port *uart)
{
	int x_pos, pos, flags;

	spin_lock_irqsave(&uart->port.lock, flags);

	uart->rx_dma_nrows = get_dma_curr_ycount(uart->rx_dma_channel);
	x_pos = get_dma_curr_xcount(uart->rx_dma_channel);
	uart->rx_dma_nrows = DMA_RX_YCOUNT - uart->rx_dma_nrows;
	if (uart->rx_dma_nrows == DMA_RX_YCOUNT)
		uart->rx_dma_nrows = 0;
	x_pos = DMA_RX_XCOUNT - x_pos;
	if (x_pos == DMA_RX_XCOUNT)
		x_pos = 0;

	pos = uart->rx_dma_nrows * DMA_RX_XCOUNT + x_pos;
	if (pos != uart->rx_dma_buf.tail) {
		uart->rx_dma_buf.head = pos;
		bfin_serial_dma_rx_chars(uart);
		uart->rx_dma_buf.tail = uart->rx_dma_buf.head;
	}

	spin_unlock_irqrestore(&uart->port.lock, flags);

	mod_timer(&(uart->rx_dma_timer), jiffies + DMA_RX_FLUSH_JIFFIES);
}
Example #4
0
static void bfin_serial_rx_chars(struct bfin_serial_port *uart)
{
	struct tty_struct *tty = NULL;
	unsigned int status, ch, flg;
	static struct timeval anomaly_start = { .tv_sec = 0 };

	status = UART_GET_LSR(uart);
	UART_CLEAR_LSR(uart);

 	ch = UART_GET_CHAR(uart);
 	uart->port.icount.rx++;

#if defined(CONFIG_KGDB_SERIAL_CONSOLE) || \
	defined(CONFIG_KGDB_SERIAL_CONSOLE_MODULE)
	if (kgdb_connected && kgdboc_port_line == uart->port.line
		&& kgdboc_break_enabled)
		if (ch == 0x3) {/* Ctrl + C */
			kgdb_breakpoint();
			return;
		}

	if (!uart->port.state || !uart->port.state->port.tty)
		return;
#endif
	tty = uart->port.state->port.tty;

	if (ANOMALY_05000363) {
		/* The BF533 (and BF561) family of processors have a nice anomaly
		 * where they continuously generate characters for a "single" break.
		 * We have to basically ignore this flood until the "next" valid
		 * character comes across.  Due to the nature of the flood, it is
		 * not possible to reliably catch bytes that are sent too quickly
		 * after this break.  So application code talking to the Blackfin
		 * which sends a break signal must allow at least 1.5 character
		 * times after the end of the break for things to stabilize.  This
		 * timeout was picked as it must absolutely be larger than 1
		 * character time +/- some percent.  So 1.5 sounds good.  All other
		 * Blackfin families operate properly.  Woo.
		 */
		if (anomaly_start.tv_sec) {
			struct timeval curr;
			suseconds_t usecs;

			if ((~ch & (~ch + 1)) & 0xff)
				goto known_good_char;

			do_gettimeofday(&curr);
			if (curr.tv_sec - anomaly_start.tv_sec > 1)
				goto known_good_char;

			usecs = 0;
			if (curr.tv_sec != anomaly_start.tv_sec)
				usecs += USEC_PER_SEC;
			usecs += curr.tv_usec - anomaly_start.tv_usec;

			if (usecs > UART_GET_ANOMALY_THRESHOLD(uart))
				goto known_good_char;

			if (ch)
				anomaly_start.tv_sec = 0;
			else
				anomaly_start = curr;

			return;

 known_good_char:
			status &= ~BI;
			anomaly_start.tv_sec = 0;
		}
	}

	if (status & BI) {
		if (ANOMALY_05000363)
			if (bfin_revid() < 5)
				do_gettimeofday(&anomaly_start);
		uart->port.icount.brk++;
		if (uart_handle_break(&uart->port))
			goto ignore_char;
		status &= ~(PE | FE);
	}
	if (status & PE)
		uart->port.icount.parity++;
	if (status & OE)
		uart->port.icount.overrun++;
	if (status & FE)
		uart->port.icount.frame++;

	status &= uart->port.read_status_mask;

	if (status & BI)
		flg = TTY_BREAK;
	else if (status & PE)
		flg = TTY_PARITY;
	else if (status & FE)
		flg = TTY_FRAME;
	else
		flg = TTY_NORMAL;

	if (uart_handle_sysrq_char(&uart->port, ch))
		goto ignore_char;

	uart_insert_char(&uart->port, status, OE, ch, flg);

 ignore_char:
	tty_flip_buffer_push(tty);
}

static void bfin_serial_tx_chars(struct bfin_serial_port *uart)
{
	struct circ_buf *xmit = &uart->port.state->xmit;

	if (uart_circ_empty(xmit) || uart_tx_stopped(&uart->port)) {
#ifdef CONFIG_BF54x
		/* Clear TFI bit */
		UART_PUT_LSR(uart, TFI);
#endif
		/* Anomaly notes:
		 *  05000215 -	we always clear ETBEI within last UART TX
		 *		interrupt to end a string. It is always set
		 *		when start a new tx.
		 */
		UART_CLEAR_IER(uart, ETBEI);
		return;
	}

	if (uart->port.x_char) {
		UART_PUT_CHAR(uart, uart->port.x_char);
		uart->port.icount.tx++;
		uart->port.x_char = 0;
	}

	while ((UART_GET_LSR(uart) & THRE) && xmit->tail != xmit->head) {
		UART_PUT_CHAR(uart, xmit->buf[xmit->tail]);
		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
		uart->port.icount.tx++;
	}

	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
		uart_write_wakeup(&uart->port);
}

static irqreturn_t bfin_serial_rx_int(int irq, void *dev_id)
{
	struct bfin_serial_port *uart = dev_id;

	while (UART_GET_LSR(uart) & DR)
		bfin_serial_rx_chars(uart);

	return IRQ_HANDLED;
}

static irqreturn_t bfin_serial_tx_int(int irq, void *dev_id)
{
	struct bfin_serial_port *uart = dev_id;

#ifdef CONFIG_SERIAL_BFIN_HARD_CTSRTS
	if (uart->scts && !(bfin_serial_get_mctrl(&uart->port) & TIOCM_CTS)) {
		uart->scts = 0;
		uart_handle_cts_change(&uart->port, uart->scts);
	}
#endif
	spin_lock(&uart->port.lock);
	if (UART_GET_LSR(uart) & THRE)
		bfin_serial_tx_chars(uart);
	spin_unlock(&uart->port.lock);

	return IRQ_HANDLED;
}
#endif

#ifdef CONFIG_SERIAL_BFIN_DMA
static void bfin_serial_dma_tx_chars(struct bfin_serial_port *uart)
{
	struct circ_buf *xmit = &uart->port.state->xmit;

	uart->tx_done = 0;

	if (uart_circ_empty(xmit) || uart_tx_stopped(&uart->port)) {
		uart->tx_count = 0;
		uart->tx_done = 1;
		return;
	}

	if (uart->port.x_char) {
		UART_PUT_CHAR(uart, uart->port.x_char);
		uart->port.icount.tx++;
		uart->port.x_char = 0;
	}

	uart->tx_count = CIRC_CNT(xmit->head, xmit->tail, UART_XMIT_SIZE);
	if (uart->tx_count > (UART_XMIT_SIZE - xmit->tail))
		uart->tx_count = UART_XMIT_SIZE - xmit->tail;
	blackfin_dcache_flush_range((unsigned long)(xmit->buf+xmit->tail),
					(unsigned long)(xmit->buf+xmit->tail+uart->tx_count));
	set_dma_config(uart->tx_dma_channel,
		set_bfin_dma_config(DIR_READ, DMA_FLOW_STOP,
			INTR_ON_BUF,
			DIMENSION_LINEAR,
			DATA_SIZE_8,
			DMA_SYNC_RESTART));
	set_dma_start_addr(uart->tx_dma_channel, (unsigned long)(xmit->buf+xmit->tail));
	set_dma_x_count(uart->tx_dma_channel, uart->tx_count);
	set_dma_x_modify(uart->tx_dma_channel, 1);
	SSYNC();
	enable_dma(uart->tx_dma_channel);

	UART_SET_IER(uart, ETBEI);
}

static void bfin_serial_dma_rx_chars(struct bfin_serial_port *uart)
{
	struct tty_struct *tty = uart->port.state->port.tty;
	int i, flg, status;

	status = UART_GET_LSR(uart);
	UART_CLEAR_LSR(uart);

	uart->port.icount.rx +=
		CIRC_CNT(uart->rx_dma_buf.head, uart->rx_dma_buf.tail,
		UART_XMIT_SIZE);

	if (status & BI) {
		uart->port.icount.brk++;
		if (uart_handle_break(&uart->port))
			goto dma_ignore_char;
		status &= ~(PE | FE);
	}
	if (status & PE)
		uart->port.icount.parity++;
	if (status & OE)
		uart->port.icount.overrun++;
	if (status & FE)
		uart->port.icount.frame++;

	status &= uart->port.read_status_mask;

	if (status & BI)
		flg = TTY_BREAK;
	else if (status & PE)
		flg = TTY_PARITY;
	else if (status & FE)
		flg = TTY_FRAME;
	else
		flg = TTY_NORMAL;

	for (i = uart->rx_dma_buf.tail; ; i++) {
		if (i >= UART_XMIT_SIZE)
			i = 0;
		if (i == uart->rx_dma_buf.head)
			break;
		if (!uart_handle_sysrq_char(&uart->port, uart->rx_dma_buf.buf[i]))
			uart_insert_char(&uart->port, status, OE,
				uart->rx_dma_buf.buf[i], flg);
	}

 dma_ignore_char:
	tty_flip_buffer_push(tty);
}

void bfin_serial_rx_dma_timeout(struct bfin_serial_port *uart)
{
	int x_pos, pos;

	dma_disable_irq_nosync(uart->rx_dma_channel);
	spin_lock_bh(&uart->rx_lock);

	/* 2D DMA RX buffer ring is used. Because curr_y_count and
	 * curr_x_count can't be read as an atomic operation,
	 * curr_y_count should be read before curr_x_count. When
	 * curr_x_count is read, curr_y_count may already indicate
	 * next buffer line. But, the position calculated here is
	 * still indicate the old line. The wrong position data may
	 * be smaller than current buffer tail, which cause garbages
	 * are received if it is not prohibit.
	 */
	uart->rx_dma_nrows = get_dma_curr_ycount(uart->rx_dma_channel);
	x_pos = get_dma_curr_xcount(uart->rx_dma_channel);
	uart->rx_dma_nrows = DMA_RX_YCOUNT - uart->rx_dma_nrows;
	if (uart->rx_dma_nrows == DMA_RX_YCOUNT || x_pos == 0)
		uart->rx_dma_nrows = 0;
	x_pos = DMA_RX_XCOUNT - x_pos;
	if (x_pos == DMA_RX_XCOUNT)
		x_pos = 0;

	pos = uart->rx_dma_nrows * DMA_RX_XCOUNT + x_pos;
	/* Ignore receiving data if new position is in the same line of
	 * current buffer tail and small.
	 */
	if (pos > uart->rx_dma_buf.tail ||
		uart->rx_dma_nrows < (uart->rx_dma_buf.tail/DMA_RX_XCOUNT)) {
		uart->rx_dma_buf.head = pos;
		bfin_serial_dma_rx_chars(uart);
		uart->rx_dma_buf.tail = uart->rx_dma_buf.head;
	}

	spin_unlock_bh(&uart->rx_lock);
	dma_enable_irq(uart->rx_dma_channel);

	mod_timer(&(uart->rx_dma_timer), jiffies + DMA_RX_FLUSH_JIFFIES);
}