forked from mirrors/linux
		
	tty: xuartps: Add polled mode support for xuartps
This allows KDB/KGDB to run. Signed-off-by: Vlad Lungu <vlad.lungu@windriver.com> Signed-off-by: Soren Brinkmann <soren.brinkmann@xilinx.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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					 1 changed files with 52 additions and 0 deletions
				
			
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			@ -775,6 +775,54 @@ static void xuartps_enable_ms(struct uart_port *port)
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	/* N/A */
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}
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#ifdef CONFIG_CONSOLE_POLL
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static int xuartps_poll_get_char(struct uart_port *port)
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{
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	u32 imr;
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	int c;
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	/* Disable all interrupts */
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	imr = xuartps_readl(XUARTPS_IMR_OFFSET);
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	xuartps_writel(imr, XUARTPS_IDR_OFFSET);
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	/* Check if FIFO is empty */
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	if (xuartps_readl(XUARTPS_SR_OFFSET) & XUARTPS_SR_RXEMPTY)
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		c = NO_POLL_CHAR;
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	else /* Read a character */
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		c = (unsigned char) xuartps_readl(XUARTPS_FIFO_OFFSET);
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	/* Enable interrupts */
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	xuartps_writel(imr, XUARTPS_IER_OFFSET);
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	return c;
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}
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static void xuartps_poll_put_char(struct uart_port *port, unsigned char c)
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{
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	u32 imr;
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	/* Disable all interrupts */
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	imr = xuartps_readl(XUARTPS_IMR_OFFSET);
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	xuartps_writel(imr, XUARTPS_IDR_OFFSET);
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	/* Wait until FIFO is empty */
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	while (!(xuartps_readl(XUARTPS_SR_OFFSET) & XUARTPS_SR_TXEMPTY))
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		cpu_relax();
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	/* Write a character */
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	xuartps_writel(c, XUARTPS_FIFO_OFFSET);
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	/* Wait until FIFO is empty */
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	while (!(xuartps_readl(XUARTPS_SR_OFFSET) & XUARTPS_SR_TXEMPTY))
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		cpu_relax();
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	/* Enable interrupts */
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	xuartps_writel(imr, XUARTPS_IER_OFFSET);
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	return;
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}
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#endif
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/** The UART operations structure
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 */
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static struct uart_ops xuartps_ops = {
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			@ -807,6 +855,10 @@ static struct uart_ops xuartps_ops = {
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	.config_port	= xuartps_config_port,	/* Configure when driver
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						 * adds a xuartps port
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						 */
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#ifdef CONFIG_CONSOLE_POLL
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	.poll_get_char	= xuartps_poll_get_char,
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	.poll_put_char	= xuartps_poll_put_char,
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#endif
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};
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static struct uart_port xuartps_port[2];
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