Commit 68252424 authored by Stephen Boyd's avatar Stephen Boyd Committed by Greg Kroah-Hartman
Browse files

tty: serial: msm: Support big-endian CPUs 



To support big-endian CPUs use the string versions of the io
read/write macros on the TX/RX fifos and the non-raw variants of
the readl/writel macros throughout. This way we don't byteswap
the characters coming from the fifos but we properly deal with
the little-endian nature of the serial hardware while controlling
it.

Signed-off-by: default avatarStephen Boyd <sboyd@codeaurora.org>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent db3a1a43

drivers/tty/serial/msm_serial.c

+18 −10
Original line number Diff line number Diff line
@@ -125,14 +125,14 @@ static void handle_rx_dm(struct uart_port *port, unsigned int misr) 
	port->icount.rx += count;



	while (count > 0) {

		unsigned int c;

		unsigned char buf[4];



		sr = msm_read(port, UART_SR);

		if ((sr & UART_SR_RX_READY) == 0) {

			msm_port->old_snap_state -= count;

			break;

		}

		c = msm_read(port, UARTDM_RF);

		ioread32_rep(port->membase + UARTDM_RF, buf, 1);

		if (sr & UART_SR_RX_BREAK) {

			port->icount.brk++;

			if (uart_handle_break(port))
@@ -141,8 +141,7 @@ static void handle_rx_dm(struct uart_port *port, unsigned int misr) 
			port->icount.frame++;



		/* TODO: handle sysrq */

		tty_insert_flip_string(tport, (char *)&c,

				       (count > 4) ? 4 : count);

		tty_insert_flip_string(tport, buf, min(count, 4));

		count -= 4;

	}
@@ -219,6 +218,12 @@ static void handle_tx(struct uart_port *port) 
	struct msm_port *msm_port = UART_TO_MSM(port);

	unsigned int tx_count, num_chars;

	unsigned int tf_pointer = 0;

	void __iomem *tf;



	if (msm_port->is_uartdm)

		tf = port->membase + UARTDM_TF;

	else

		tf = port->membase + UART_TF;



	tx_count = uart_circ_chars_pending(xmit);

	tx_count = min3(tx_count, (unsigned int)UART_XMIT_SIZE - xmit->tail,
@@ -228,8 +233,7 @@ static void handle_tx(struct uart_port *port) 
		if (msm_port->is_uartdm)

			reset_dm_count(port, tx_count + 1);



		msm_write(port, port->x_char,

			  msm_port->is_uartdm ? UARTDM_TF : UART_TF);

		iowrite8_rep(tf, &port->x_char, 1);

		port->icount.tx++;

		port->x_char = 0;

	} else if (tx_count && msm_port->is_uartdm) {
@@ -239,7 +243,6 @@ static void handle_tx(struct uart_port *port) 
	while (tf_pointer < tx_count) {

		int i;

		char buf[4] = { 0 };

		unsigned int *bf = (unsigned int *)&buf;



		if (!(msm_read(port, UART_SR) & UART_SR_TX_READY))

			break;
@@ -255,7 +258,7 @@ static void handle_tx(struct uart_port *port) 
			port->icount.tx++;

		}



		msm_write(port, *bf, msm_port->is_uartdm ? UARTDM_TF : UART_TF);

		iowrite32_rep(tf, buf, 1);

		xmit->tail = (xmit->tail + num_chars) & (UART_XMIT_SIZE - 1);

		tf_pointer += num_chars;

	}
@@ -861,12 +864,18 @@ static void msm_console_write(struct console *co, const char *s, 
	struct msm_port *msm_port;

	int num_newlines = 0;

	bool replaced = false;

	void __iomem *tf;



	BUG_ON(co->index < 0 || co->index >= UART_NR);



	port = get_port_from_line(co->index);

	msm_port = UART_TO_MSM(port);



	if (msm_port->is_uartdm)

		tf = port->membase + UARTDM_TF;

	else

		tf = port->membase + UART_TF;



	/* Account for newlines that will get a carriage return added */

	for (i = 0; i < count; i++)

		if (s[i] == '\n')
@@ -882,7 +891,6 @@ static void msm_console_write(struct console *co, const char *s, 
		int j;

		unsigned int num_chars;

		char buf[4] = { 0 };

		unsigned int *bf = (unsigned int *)&buf;



		if (msm_port->is_uartdm)

			num_chars = min(count - i, (unsigned int)sizeof(buf));
@@ -907,7 +915,7 @@ static void msm_console_write(struct console *co, const char *s, 
		while (!(msm_read(port, UART_SR) & UART_SR_TX_READY))

			cpu_relax();



		msm_write(port, *bf, msm_port->is_uartdm ? UARTDM_TF : UART_TF);

		iowrite32_rep(tf, buf, 1);

		i += num_chars;

	}

	spin_unlock(&port->lock);

drivers/tty/serial/msm_serial.h

+2 −2
Original line number Diff line number Diff line
@@ -126,13 +126,13 @@ 
static inline

void msm_write(struct uart_port *port, unsigned int val, unsigned int off)

{

	__raw_writel(val, port->membase + off);

	writel_relaxed(val, port->membase + off);

}



static inline

unsigned int msm_read(struct uart_port *port, unsigned int off)

{

	return __raw_readl(port->membase + off);

	return readl_relaxed(port->membase + off);

}



/*

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