[PATCH 1/4] serial: 8250 driver replaceable i/o functions.

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



In order to use Cavium OCTEON specific serial i/o drivers, we first patch
the 8250 driver to use replaceable i/o functions.

Signed-off-by: David Daney <ddaney@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Tomaso Paoletti <tpaoletti@xxxxxxxxxxxxxxxxxx>
---
drivers/serial/8250.c       |  185 +++++++++++++++++++++++++++++--------------
include/linux/serial_8250.h |    2 +
include/linux/serial_core.h |    2 +
3 files changed, 131 insertions(+), 58 deletions(-)

diff --git a/drivers/serial/8250.c b/drivers/serial/8250.c
index 9ccc563..02771d6 100644
--- a/drivers/serial/8250.c
+++ b/drivers/serial/8250.c
@@ -288,16 +288,16 @@ static const u8 au_io_out_map[] = {
};

/* sane hardware needs no mapping */
-static inline int map_8250_in_reg(struct uart_8250_port *up, int offset)
+static inline int map_8250_in_reg(struct uart_port *p, int offset)
{
-	if (up->port.iotype != UPIO_AU)
+	if (p->iotype != UPIO_AU)
		return offset;
	return au_io_in_map[offset];
}

-static inline int map_8250_out_reg(struct uart_8250_port *up, int offset)
+static inline int map_8250_out_reg(struct uart_port *p, int offset)
{
-	if (up->port.iotype != UPIO_AU)
+	if (p->iotype != UPIO_AU)
		return offset;
	return au_io_out_map[offset];
}
@@ -326,16 +326,16 @@ static const u8
		[UART_SCR]	= 0x2c
	};

-static inline int map_8250_in_reg(struct uart_8250_port *up, int offset)
+static inline int map_8250_in_reg(struct uart_port *p, int offset)
{
-	if (up->port.iotype != UPIO_RM9000)
+	if (p->iotype != UPIO_RM9000)
		return offset;
	return regmap_in[offset];
}

-static inline int map_8250_out_reg(struct uart_8250_port *up, int offset)
+static inline int map_8250_out_reg(struct uart_port *p, int offset)
{
-	if (up->port.iotype != UPIO_RM9000)
+	if (p->iotype != UPIO_RM9000)
		return offset;
	return regmap_out[offset];
}
@@ -348,108 +348,170 @@ static inline int map_8250_out_reg(struct uart_8250_port *up, int offset)

#endif

-static unsigned int serial_in(struct uart_8250_port *up, int offset)
+static unsigned int hub6_serial_in_fn(struct uart_port *p, int offset)
{
-	unsigned int tmp;
-	offset = map_8250_in_reg(up, offset) << up->port.regshift;
+	offset = map_8250_in_reg(p, offset) << p->regshift;
+	outb(p->hub6 - 1 + offset, p->iobase);
+	return inb(p->iobase + 1);
+}

-	switch (up->port.iotype) {
-	case UPIO_HUB6:
-		outb(up->port.hub6 - 1 + offset, up->port.iobase);
-		return inb(up->port.iobase + 1);
+static void hub6_serial_out_fn(struct uart_port *p, int offset, int value)
+{
+	offset = map_8250_out_reg(p, offset) << p->regshift;
+	outb(p->hub6 - 1 + offset, p->iobase);
+	outb(value, p->iobase + 1);
+}

-	case UPIO_MEM:
-	case UPIO_DWAPB:
-		return readb(up->port.membase + offset);
+static unsigned int mem_serial_in_fn(struct uart_port *p, int offset)
+{
+	offset = map_8250_in_reg(p, offset) << p->regshift;
+	return readb(p->membase + offset);
+}

-	case UPIO_RM9000:
-	case UPIO_MEM32:
-		return readl(up->port.membase + offset);
+static void mem_serial_out_fn(struct uart_port *p, int offset, int value)
+{
+	offset = map_8250_out_reg(p, offset) << p->regshift;
+	writeb(value, p->membase + offset);
+}
+
+static void mem32_serial_out_fn(struct uart_port *p, int offset, int value)
+{
+	offset = map_8250_out_reg(p, offset) << p->regshift;
+	writel(value, p->membase + offset);
+}
+
+static unsigned int mem32_serial_in_fn(struct uart_port *p, int offset)
+{
+	offset = map_8250_in_reg(p, offset) << p->regshift;
+	return readl(p->membase + offset);
+}

#ifdef CONFIG_SERIAL_8250_AU1X00
-	case UPIO_AU:
-		return __raw_readl(up->port.membase + offset);
+static unsigned int au_serial_in_fn(struct uart_port *p, int offset)
+{
+	offset = map_8250_in_reg(p, offset) << p->regshift;
+	return __raw_readl(p->membase + offset);
+}
+
+static void au_serial_out_fn(struct uart_port *p, int offset, int value)
+{
+	offset = map_8250_out_reg(p, offset) << p->regshift;
+	__raw_writel(value, p->membase + offset);
+}
#endif

-	case UPIO_TSI:
-		if (offset == UART_IIR) {
-			tmp = readl(up->port.membase + (UART_IIR & ~3));
-			return (tmp >> 16) & 0xff; /* UART_IIR % 4 == 2 */
-		} else
-			return readb(up->port.membase + offset);
+static unsigned int tsi_serial_in_fn(struct uart_port *p, int offset)
+{
+	unsigned int tmp;
+	offset = map_8250_in_reg(p, offset) << p->regshift;
+	if (offset == UART_IIR) {
+		tmp = readl(p->membase + (UART_IIR & ~3));
+		return (tmp >> 16) & 0xff; /* UART_IIR % 4 == 2 */
+	} else
+		return readb(p->membase + offset);
+}

-	default:
-		return inb(up->port.iobase + offset);
-	}
+static void tsi_serial_out_fn(struct uart_port *p, int offset, int value)
+{
+	offset = map_8250_out_reg(p, offset) << p->regshift;
+	if (!((offset == UART_IER) && (value & UART_IER_UUE)))
+		writeb(value, p->membase + offset);
}

-static void
-serial_out(struct uart_8250_port *up, int offset, int value)
+static void dwapb_serial_out_fn(struct uart_port *p, int offset, int value)
{
-	/* Save the offset before it's remapped */
	int save_offset = offset;
-	offset = map_8250_out_reg(up, offset) << up->port.regshift;
+	offset = map_8250_out_reg(p, offset) << p->regshift;
+	/* Save the LCR value so it can be re-written when a
+	 * Busy Detect interrupt occurs. */
+	if (save_offset == UART_LCR) {
+		struct uart_8250_port *up = (struct uart_8250_port *)p;
+		up->lcr = value;
+	}
+	writeb(value, p->membase + offset);
+	/* Read the IER to ensure any interrupt is cleared before
+	 * returning from ISR. */
+	if (save_offset == UART_TX || save_offset == UART_IER)
+		value = p->serial_in_fn(p, UART_IER);
+}

-	switch (up->port.iotype) {
+static unsigned int io_serial_in_fn(struct uart_port *p, int offset)
+{
+	offset = map_8250_in_reg(p, offset) << p->regshift;
+	return inb(p->iobase + offset);
+}
+
+static void io_serial_out_fn(struct uart_port *p, int offset, int value)
+{
+	offset = map_8250_out_reg(p, offset) << p->regshift;
+	outb(value, p->iobase + offset);
+}
+
+static void set_io_fns_from_upio(struct uart_port *p)
+{
+	switch (p->iotype) {
	case UPIO_HUB6:
-		outb(up->port.hub6 - 1 + offset, up->port.iobase);
-		outb(value, up->port.iobase + 1);
+		p->serial_in_fn = hub6_serial_in_fn;
+		p->serial_out_fn = hub6_serial_out_fn;
		break;

	case UPIO_MEM:
-		writeb(value, up->port.membase + offset);
+		p->serial_in_fn = mem_serial_in_fn;
+		p->serial_out_fn = mem_serial_out_fn;
		break;

	case UPIO_RM9000:
	case UPIO_MEM32:
-		writel(value, up->port.membase + offset);
+		p->serial_in_fn = mem32_serial_in_fn;
+		p->serial_out_fn = mem32_serial_out_fn;
		break;

#ifdef CONFIG_SERIAL_8250_AU1X00
	case UPIO_AU:
-		__raw_writel(value, up->port.membase + offset);
+		p->serial_in_fn = au_serial_in_fn;
+		p->serial_out_fn = au_serial_out_fn;
		break;
#endif
	case UPIO_TSI:
-		if (!((offset == UART_IER) && (value & UART_IER_UUE)))
-			writeb(value, up->port.membase + offset);
+		p->serial_in_fn = tsi_serial_in_fn;
+		p->serial_out_fn = tsi_serial_out_fn;
		break;

	case UPIO_DWAPB:
-		/* Save the LCR value so it can be re-written when a
-		 * Busy Detect interrupt occurs. */
-		if (save_offset == UART_LCR)
-			up->lcr = value;
-		writeb(value, up->port.membase + offset);
-		/* Read the IER to ensure any interrupt is cleared before
-		 * returning from ISR. */
-		if (save_offset == UART_TX || save_offset == UART_IER)
-			value = serial_in(up, UART_IER);
+		p->serial_in_fn = mem_serial_in_fn;
+		p->serial_out_fn = dwapb_serial_out_fn;
		break;

	default:
-		outb(value, up->port.iobase + offset);
+		p->serial_in_fn = io_serial_in_fn;
+		p->serial_out_fn = io_serial_out_fn;
+		break;
	}
}

static void
serial_out_sync(struct uart_8250_port *up, int offset, int value)
{
-	switch (up->port.iotype) {
+	struct uart_port *p = &up->port;
+	switch (p->iotype) {
	case UPIO_MEM:
	case UPIO_MEM32:
#ifdef CONFIG_SERIAL_8250_AU1X00
	case UPIO_AU:
#endif
	case UPIO_DWAPB:
-		serial_out(up, offset, value);
-		serial_in(up, UART_LCR);	/* safe, no side-effects */
+		p->serial_out_fn(p, offset, value);
+		p->serial_in_fn(p, UART_LCR);	/* safe, no side-effects */
		break;
	default:
-		serial_out(up, offset, value);
+		p->serial_out_fn(p, offset, value);
	}
}

+#define serial_in(up, offset)		\
+	(up->port.serial_in_fn(&(up)->port, (offset)))
+#define serial_out(up, offset, value)	\
+	(up->port.serial_out_fn(&(up)->port, (offset), (value)))
/*
 * We used to support using pause I/O for certain machines.  We
 * haven't supported this for a while, but just in case it's badly
@@ -2511,6 +2573,7 @@ static void __init serial8250_isa_init_ports(void)
		up->port.membase  = old_serial_port[i].iomem_base;
		up->port.iotype   = old_serial_port[i].io_type;
		up->port.regshift = old_serial_port[i].iomem_reg_shift;
+		set_io_fns_from_upio(&up->port);
		if (share_irqs)
			up->port.flags |= UPF_SHARE_IRQ;
	}
@@ -2912,6 +2975,12 @@ int serial8250_register_port(struct uart_port *port)
		uart->port.private_data = port->private_data;
		if (port->dev)
			uart->port.dev = port->dev;
+		set_io_fns_from_upio(&uart->port);
+		/* Possibly override default I/O functions.  */
+		if (port->serial_in_fn)
+			uart->port.serial_in_fn = port->serial_in_fn;
+		if (port->serial_out_fn)
+			uart->port.serial_out_fn = port->serial_out_fn;

		ret = uart_add_one_port(&serial8250_reg, &uart->port);
		if (ret == 0)
diff --git a/include/linux/serial_8250.h b/include/linux/serial_8250.h
index 3d37c94..eb08b04 100644
--- a/include/linux/serial_8250.h
+++ b/include/linux/serial_8250.h
@@ -28,6 +28,8 @@ struct plat_serial8250_port {
	unsigned char	iotype;		/* UPIO_* */
	unsigned char	hub6;
	upf_t		flags;		/* UPF_* flags */
+	unsigned int	(*serial_in_fn)(struct uart_port *, int);
+	void		(*serial_out_fn)(struct uart_port *, int, int);
};

/*
diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h
index 3b2f6c0..3a4afcf 100644
--- a/include/linux/serial_core.h
+++ b/include/linux/serial_core.h
@@ -243,6 +243,8 @@ struct uart_port {
	spinlock_t		lock;			/* port lock */
	unsigned int		iobase;			/* in/out[bwl] */
	unsigned char __iomem	*membase;		/* read/write[bwl] */
+	unsigned int		(*serial_in_fn)(struct uart_port *, int);
+	void			(*serial_out_fn)(struct uart_port *, int, int);
	unsigned int		irq;			/* irq number */
	unsigned int		uartclk;		/* base uart clock */
	unsigned int		fifosize;		/* tx fifo size */


[Index of Archives]     [Linux MIPS Home]     [LKML Archive]     [Linux ARM Kernel]     [Linux ARM]     [Linux]     [Git]     [Yosemite News]     [Linux SCSI]     [Linux Hams]

  Powered by Linux