serial: sh-sci: Abstract register maps.

This takes a bit of a sledgehammer to the horribly CPU subtype
ifdef-ridden header and abstracts all of the different register layouts
in to distinct types which in turn can be overriden on a per-port basis,
or permitted to default to the map matching the port type at probe time.

In the process this ultimately fixes up inumerable bugs with mismatches
on various CPU types (particularly the legacy ones that were obviously
broken years ago and no one noticed) and provides a more tightly coupled
and consolidated platform for extending and implementing generic
features.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>

1 files changed, 273 insertions, 91 deletions

diff --git a/drivers/tty/serial/sh-sci.c b/drivers/tty/serial/sh-sci.c
index 3248ddaa889d..14e1bae50392 100644
--- a/drivers/tty/serial/sh-sci.c
+++ b/drivers/tty/serial/sh-sci.c
@@ -117,6 +117,255 @@ to_sci_port(struct uart_port *uart)
 	return container_of(uart, struct sci_port, port);
 }
 
+struct plat_sci_reg {
+	u8 offset, size;
+};
+
+/* Helper for invalidating specific entries of an inherited map. */
+#define sci_reg_invalid	{ .offset = 0, .size = 0 }
+
+static struct plat_sci_reg sci_regmap[SCIx_NR_REGTYPES][SCIx_NR_REGS] = {
+	[SCIx_PROBE_REGTYPE] = {
+		[0 ... SCIx_NR_REGS - 1] = sci_reg_invalid,
+	},
+
+	/*
+	 * Common SCI definitions, dependent on the port's regshift
+	 * value.
+	 */
+	[SCIx_SCI_REGTYPE] = {
+		[SCSMR]		= { 0x00,  8 },
+		[SCBRR]		= { 0x01,  8 },
+		[SCSCR]		= { 0x02,  8 },
+		[SCxTDR]	= { 0x03,  8 },
+		[SCxSR]		= { 0x04,  8 },
+		[SCxRDR]	= { 0x05,  8 },
+		[SCFCR]		= sci_reg_invalid,
+		[SCFDR]		= sci_reg_invalid,
+		[SCTFDR]	= sci_reg_invalid,
+		[SCRFDR]	= sci_reg_invalid,
+		[SCSPTR]	= sci_reg_invalid,
+		[SCLSR]		= sci_reg_invalid,
+	},
+
+	/*
+	 * Common definitions for legacy IrDA ports, dependent on
+	 * regshift value.
+	 */
+	[SCIx_IRDA_REGTYPE] = {
+		[SCSMR]		= { 0x00,  8 },
+		[SCBRR]		= { 0x01,  8 },
+		[SCSCR]		= { 0x02,  8 },
+		[SCxTDR]	= { 0x03,  8 },
+		[SCxSR]		= { 0x04,  8 },
+		[SCxRDR]	= { 0x05,  8 },
+		[SCFCR]		= { 0x06,  8 },
+		[SCFDR]		= { 0x07, 16 },
+		[SCTFDR]	= sci_reg_invalid,
+		[SCRFDR]	= sci_reg_invalid,
+		[SCSPTR]	= sci_reg_invalid,
+		[SCLSR]		= sci_reg_invalid,
+	},
+
+	/*
+	 * Common SCIFA definitions.
+	 */
+	[SCIx_SCIFA_REGTYPE] = {
+		[SCSMR]		= { 0x00, 16 },
+		[SCBRR]		= { 0x04,  8 },
+		[SCSCR]		= { 0x08, 16 },
+		[SCxTDR]	= { 0x20,  8 },
+		[SCxSR]		= { 0x14, 16 },
+		[SCxRDR]	= { 0x24,  8 },
+		[SCFCR]		= { 0x18, 16 },
+		[SCFDR]		= { 0x1c, 16 },
+		[SCTFDR]	= sci_reg_invalid,
+		[SCRFDR]	= sci_reg_invalid,
+		[SCSPTR]	= sci_reg_invalid,
+		[SCLSR]		= sci_reg_invalid,
+	},
+
+	/*
+	 * Common SCIFB definitions.
+	 */
+	[SCIx_SCIFB_REGTYPE] = {
+		[SCSMR]		= { 0x00, 16 },
+		[SCBRR]		= { 0x04,  8 },
+		[SCSCR]		= { 0x08, 16 },
+		[SCxTDR]	= { 0x40,  8 },
+		[SCxSR]		= { 0x14, 16 },
+		[SCxRDR]	= { 0x60,  8 },
+		[SCFCR]		= { 0x18, 16 },
+		[SCFDR]		= { 0x1c, 16 },
+		[SCTFDR]	= sci_reg_invalid,
+		[SCRFDR]	= sci_reg_invalid,
+		[SCSPTR]	= sci_reg_invalid,
+		[SCLSR]		= sci_reg_invalid,
+	},
+
+	/*
+	 * Common SH-3 SCIF definitions.
+	 */
+	[SCIx_SH3_SCIF_REGTYPE] = {
+		[SCSMR]		= { 0x00,  8 },
+		[SCBRR]		= { 0x02,  8 },
+		[SCSCR]		= { 0x04,  8 },
+		[SCxTDR]	= { 0x06,  8 },
+		[SCxSR]		= { 0x08, 16 },
+		[SCxRDR]	= { 0x0a,  8 },
+		[SCFCR]		= { 0x0c,  8 },
+		[SCFDR]		= { 0x0e, 16 },
+		[SCTFDR]	= sci_reg_invalid,
+		[SCRFDR]	= sci_reg_invalid,
+		[SCSPTR]	= sci_reg_invalid,
+		[SCLSR]		= sci_reg_invalid,
+	},
+
+	/*
+	 * Common SH-4(A) SCIF(B) definitions.
+	 */
+	[SCIx_SH4_SCIF_REGTYPE] = {
+		[SCSMR]		= { 0x00, 16 },
+		[SCBRR]		= { 0x04,  8 },
+		[SCSCR]		= { 0x08, 16 },
+		[SCxTDR]	= { 0x0c,  8 },
+		[SCxSR]		= { 0x10, 16 },
+		[SCxRDR]	= { 0x14,  8 },
+		[SCFCR]		= { 0x18, 16 },
+		[SCFDR]		= { 0x1c, 16 },
+		[SCTFDR]	= sci_reg_invalid,
+		[SCRFDR]	= sci_reg_invalid,
+		[SCSPTR]	= { 0x20, 16 },
+		[SCLSR]		= { 0x24, 16 },
+	},
+
+	/*
+	 * Common SH-4(A) SCIF(B) definitions for ports without an SCSPTR
+	 * register.
+	 */
+	[SCIx_SH4_SCIF_NO_SCSPTR_REGTYPE] = {
+		[SCSMR]		= { 0x00, 16 },
+		[SCBRR]		= { 0x04,  8 },
+		[SCSCR]		= { 0x08, 16 },
+		[SCxTDR]	= { 0x0c,  8 },
+		[SCxSR]		= { 0x10, 16 },
+		[SCxRDR]	= { 0x14,  8 },
+		[SCFCR]		= { 0x18, 16 },
+		[SCFDR]		= { 0x1c, 16 },
+		[SCTFDR]	= sci_reg_invalid,
+		[SCRFDR]	= sci_reg_invalid,
+		[SCSPTR]	= sci_reg_invalid,
+		[SCLSR]		= { 0x24, 16 },
+	},
+
+	/*
+	 * Common SH-4(A) SCIF(B) definitions for ports with FIFO data
+	 * count registers.
+	 */
+	[SCIx_SH4_SCIF_FIFODATA_REGTYPE] = {
+		[SCSMR]		= { 0x00, 16 },
+		[SCBRR]		= { 0x04,  8 },
+		[SCSCR]		= { 0x08, 16 },
+		[SCxTDR]	= { 0x0c,  8 },
+		[SCxSR]		= { 0x10, 16 },
+		[SCxRDR]	= { 0x14,  8 },
+		[SCFCR]		= { 0x18, 16 },
+		[SCFDR]		= { 0x1c, 16 },
+		[SCTFDR]	= { 0x1c, 16 },	/* aliased to SCFDR */
+		[SCRFDR]	= { 0x20, 16 },
+		[SCSPTR]	= { 0x24, 16 },
+		[SCLSR]		= { 0x28, 16 },
+	},
+
+	/*
+	 * SH7705-style SCIF(B) ports, lacking both SCSPTR and SCLSR
+	 * registers.
+	 */
+	[SCIx_SH7705_SCIF_REGTYPE] = {
+		[SCSMR]		= { 0x00, 16 },
+		[SCBRR]		= { 0x04,  8 },
+		[SCSCR]		= { 0x08, 16 },
+		[SCxTDR]	= { 0x20,  8 },
+		[SCxSR]		= { 0x14, 16 },
+		[SCxRDR]	= { 0x24,  8 },
+		[SCFCR]		= { 0x18, 16 },
+		[SCFDR]		= { 0x1c, 16 },
+		[SCTFDR]	= sci_reg_invalid,
+		[SCRFDR]	= sci_reg_invalid,
+		[SCSPTR]	= sci_reg_invalid,
+		[SCLSR]		= sci_reg_invalid,
+	},
+};
+
+/*
+ * The "offset" here is rather misleading, in that it refers to an enum
+ * value relative to the port mapping rather than the fixed offset
+ * itself, which needs to be manually retrieved from the platform's
+ * register map for the given port.
+ */
+static unsigned int sci_serial_in(struct uart_port *p, int offset)
+{
+	struct sci_port *s = to_sci_port(p);
+	struct plat_sci_reg *reg = sci_regmap[s->cfg->regtype] + offset;
+
+	if (reg->size == 8)
+		return ioread8(p->membase + (reg->offset << p->regshift));
+	else if (reg->size == 16)
+		return ioread16(p->membase + (reg->offset << p->regshift));
+	else
+		WARN(1, "Invalid register access\n");
+
+	return 0;
+}
+
+static void sci_serial_out(struct uart_port *p, int offset, int value)
+{
+	struct sci_port *s = to_sci_port(p);
+	struct plat_sci_reg *reg = sci_regmap[s->cfg->regtype] + offset;
+
+	if (reg->size == 8)
+		iowrite8(value, p->membase + (reg->offset << p->regshift));
+	else if (reg->size == 16)
+		iowrite16(value, p->membase + (reg->offset << p->regshift));
+	else
+		WARN(1, "Invalid register access\n");
+}
+
+#define sci_in(up, offset)		(up->serial_in(up, offset))
+#define sci_out(up, offset, value)	(up->serial_out(up, offset, value))
+
+static int sci_probe_regmap(struct plat_sci_port *cfg)
+{
+	switch (cfg->type) {
+	case PORT_SCI:
+		cfg->regtype = SCIx_SCI_REGTYPE;
+		break;
+	case PORT_IRDA:
+		cfg->regtype = SCIx_IRDA_REGTYPE;
+		break;
+	case PORT_SCIFA:
+		cfg->regtype = SCIx_SCIFA_REGTYPE;
+		break;
+	case PORT_SCIFB:
+		cfg->regtype = SCIx_SCIFB_REGTYPE;
+		break;
+	case PORT_SCIF:
+		/*
+		 * The SH-4 is a bit of a misnomer here, although that's
+		 * where this particular port layout originated. This
+		 * configuration (or some slight variation thereof)
+		 * remains the dominant model for all SCIFs.
+		 */
+		cfg->regtype = SCIx_SH4_SCIF_REGTYPE;
+		break;
+	default:
+		printk(KERN_ERR "Can't probe register map for given port\n");
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
 #if defined(CONFIG_CONSOLE_POLL) || defined(CONFIG_SERIAL_SH_SCI_CONSOLE)
 
 #ifdef CONFIG_CONSOLE_POLL
@@ -160,103 +409,29 @@ static void sci_poll_put_char(struct uart_port *port, unsigned char c)
 }
 #endif /* CONFIG_CONSOLE_POLL || CONFIG_SERIAL_SH_SCI_CONSOLE */
 
-#if defined(CONFIG_CPU_SUBTYPE_SH7710) || defined(CONFIG_CPU_SUBTYPE_SH7712)
-static inline void sci_init_pins(struct uart_port *port, unsigned int cflag)
-{
-	if (port->mapbase == 0xA4400000) {
-		__raw_writew(__raw_readw(PACR) & 0xffc0, PACR);
-		__raw_writew(__raw_readw(PBCR) & 0x0fff, PBCR);
-	} else if (port->mapbase == 0xA4410000)
-		__raw_writew(__raw_readw(PBCR) & 0xf003, PBCR);
-}
-#elif defined(CONFIG_CPU_SUBTYPE_SH7720) || defined(CONFIG_CPU_SUBTYPE_SH7721)
-static inline void sci_init_pins(struct uart_port *port, unsigned int cflag)
-{
-	unsigned short data;
-
-	if (cflag & CRTSCTS) {
-		/* enable RTS/CTS */
-		if (port->mapbase == 0xa4430000) { /* SCIF0 */
-			/* Clear PTCR bit 9-2; enable all scif pins but sck */
-			data = __raw_readw(PORT_PTCR);
-			__raw_writew((data & 0xfc03), PORT_PTCR);
-		} else if (port->mapbase == 0xa4438000) { /* SCIF1 */
-			/* Clear PVCR bit 9-2 */
-			data = __raw_readw(PORT_PVCR);
-			__raw_writew((data & 0xfc03), PORT_PVCR);
-		}
-	} else {
-		if (port->mapbase == 0xa4430000) { /* SCIF0 */
-			/* Clear PTCR bit 5-2; enable only tx and rx  */
-			data = __raw_readw(PORT_PTCR);
-			__raw_writew((data & 0xffc3), PORT_PTCR);
-		} else if (port->mapbase == 0xa4438000) { /* SCIF1 */
-			/* Clear PVCR bit 5-2 */
-			data = __raw_readw(PORT_PVCR);
-			__raw_writew((data & 0xffc3), PORT_PVCR);
-		}
-	}
-}
-#elif defined(CONFIG_CPU_SH3)
-/* For SH7705, SH7706, SH7707, SH7709, SH7709A, SH7729 */
-static inline void sci_init_pins(struct uart_port *port, unsigned int cflag)
+static void sci_init_pins(struct uart_port *port, unsigned int cflag)
 {
-	unsigned short data;
-
-	/* We need to set SCPCR to enable RTS/CTS */
-	data = __raw_readw(SCPCR);
-	/* Clear out SCP7MD1,0, SCP6MD1,0, SCP4MD1,0*/
-	__raw_writew(data & 0x0fcf, SCPCR);
-
-	if (!(cflag & CRTSCTS)) {
-		/* We need to set SCPCR to enable RTS/CTS */
-		data = __raw_readw(SCPCR);
-		/* Clear out SCP7MD1,0, SCP4MD1,0,
-		   Set SCP6MD1,0 = {01} (output)  */
-		__raw_writew((data & 0x0fcf) | 0x1000, SCPCR);
+	struct sci_port *s = to_sci_port(port);
+	struct plat_sci_reg *reg = sci_regmap[s->cfg->regtype] + SCSPTR;
 
-		data = __raw_readb(SCPDR);
-		/* Set /RTS2 (bit6) = 0 */
-		__raw_writeb(data & 0xbf, SCPDR);
+	/*
+	 * Use port-specific handler if provided.
+	 */
+	if (s->cfg->ops && s->cfg->ops->init_pins) {
+		s->cfg->ops->init_pins(port, cflag);
+		return;
 	}
-}
-#elif defined(CONFIG_CPU_SUBTYPE_SH7722)
-static inline void sci_init_pins(struct uart_port *port, unsigned int cflag)
-{
-	unsigned short data;
 
-	if (port->mapbase == 0xffe00000) {
-		data = __raw_readw(PSCR);
-		data &= ~0x03cf;
-		if (!(cflag & CRTSCTS))
-			data |= 0x0340;
+	/*
+	 * For the generic path SCSPTR is necessary. Bail out if that's
+	 * unavailable, too.
+	 */
+	if (!reg->size)
+		return;
 
-		__raw_writew(data, PSCR);
-	}
-}
-#elif defined(CONFIG_CPU_SUBTYPE_SH7757) || \
-      defined(CONFIG_CPU_SUBTYPE_SH7763) || \
-      defined(CONFIG_CPU_SUBTYPE_SH7780) || \
-      defined(CONFIG_CPU_SUBTYPE_SH7785) || \
-      defined(CONFIG_CPU_SUBTYPE_SH7786) || \
-      defined(CONFIG_CPU_SUBTYPE_SHX3)
-static inline void sci_init_pins(struct uart_port *port, unsigned int cflag)
-{
-	if (!(cflag & CRTSCTS))
-		__raw_writew(0x0080, SCSPTR0); /* Set RTS = 1 */
-}
-#elif defined(CONFIG_CPU_SH4) && !defined(CONFIG_CPU_SH4A)
-static inline void sci_init_pins(struct uart_port *port, unsigned int cflag)
-{
 	if (!(cflag & CRTSCTS))
-		__raw_writew(0x0080, SCSPTR2); /* Set RTS = 1 */
+		sci_out(port, SCSPTR, 0x0080); /* Set RTS = 1 */
 }
-#else
-static inline void sci_init_pins(struct uart_port *port, unsigned int cflag)
-{
-	/* Nothing to do */
-}
-#endif
 
 #if defined(CONFIG_CPU_SUBTYPE_SH7760) || \
     defined(CONFIG_CPU_SUBTYPE_SH7780) || \
@@ -1752,6 +1927,9 @@ static int __devinit sci_init_single(struct platform_device *dev,
 		break;
 	}
 
+	if (p->regtype == SCIx_PROBE_REGTYPE)
+		BUG_ON(sci_probe_regmap(p) != 0);
+
 	if (dev) {
 		sci_port->iclk = clk_get(&dev->dev, "sci_ick");
 		if (IS_ERR(sci_port->iclk)) {
@@ -1812,9 +1990,10 @@ static int __devinit sci_init_single(struct platform_device *dev,
 	port->mapbase		= p->mapbase;
 	port->type		= p->type;
 	port->flags		= p->flags;
+	port->regshift		= p->regshift;
 
 	/*
-	 * The UART port needs an IRQ value, so we peg this to the TX IRQ
+	 * The UART port needs an IRQ value, so we peg this to the RX IRQ
 	 * for the multi-IRQ ports, which is where we are primarily
 	 * concerned with the shutdown path synchronization.
 	 *
@@ -1822,6 +2001,9 @@ static int __devinit sci_init_single(struct platform_device *dev,
 	 */
 	port->irq		= p->irqs[SCIx_RXI_IRQ];
 
+	port->serial_in		= sci_serial_in;
+	port->serial_out	= sci_serial_out;
+
 	if (p->dma_dev)
 		dev_dbg(port->dev, "DMA device %p, tx %d, rx %d\n",
 			p->dma_dev, p->dma_slave_tx, p->dma_slave_rx);