[SERIAL] Support Au1x00 8250 UARTs using the generic 8250 driver.

The offsets of the registers are in a different place, and
some parts cannot handle a full set of modem control signals.

Signed-off-by: Pantelis Antoniou <pantelis@embeddedalley.ocm>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

diff --git a/drivers/serial/8250.c b/drivers/serial/8250.c
index f47d2c4..186e96c 100644 (file)
--- a/drivers/serial/8250.c
+++ b/drivers/serial/8250.c
@@ -251,9 +251,53 @@ static const struct serial8250_config uart_config[] = {
        },
 };
 
+#ifdef CONFIG_SERIAL_8250_AU1X00
+
+/* Au1x00 UART hardware has a weird register layout */
+static const u8 au_io_in_map[] = {
+       [UART_RX]  = 0,
+       [UART_IER] = 2,
+       [UART_IIR] = 3,
+       [UART_LCR] = 5,
+       [UART_MCR] = 6,
+       [UART_LSR] = 7,
+       [UART_MSR] = 8,
+};
+
+static const u8 au_io_out_map[] = {
+       [UART_TX]  = 1,
+       [UART_IER] = 2,
+       [UART_FCR] = 4,
+       [UART_LCR] = 5,
+       [UART_MCR] = 6,
+};
+
+/* sane hardware needs no mapping */
+static inline int map_8250_in_reg(struct uart_8250_port *up, int offset)
+{
+       if (up->port.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)
+{
+       if (up->port.iotype != UPIO_AU)
+               return offset;
+       return au_io_out_map[offset];
+}
+
+#else
+
+/* sane hardware needs no mapping */
+#define map_8250_in_reg(up, offset) (offset)
+#define map_8250_out_reg(up, offset) (offset)
+
+#endif
+
 static _INLINE_ unsigned int serial_in(struct uart_8250_port *up, int offset)
 {
-       offset <<= up->port.regshift;
+       offset = map_8250_in_reg(up, offset) << up->port.regshift;
 
        switch (up->port.iotype) {
        case UPIO_HUB6:
@@ -266,6 +310,11 @@ static _INLINE_ unsigned int serial_in(struct uart_8250_port *up, int offset)
        case UPIO_MEM32:
                return readl(up->port.membase + offset);
 
+#ifdef CONFIG_SERIAL_8250_AU1X00
+       case UPIO_AU:
+               return __raw_readl(up->port.membase + offset);
+#endif
+
        default:
                return inb(up->port.iobase + offset);
        }
@@ -274,7 +323,7 @@ static _INLINE_ unsigned int serial_in(struct uart_8250_port *up, int offset)
 static _INLINE_ void
 serial_out(struct uart_8250_port *up, int offset, int value)
 {
-       offset <<= up->port.regshift;
+       offset = map_8250_out_reg(up, offset) << up->port.regshift;
 
        switch (up->port.iotype) {
        case UPIO_HUB6:
@@ -290,6 +339,12 @@ serial_out(struct uart_8250_port *up, int offset, int value)
                writel(value, up->port.membase + offset);
                break;
 
+#ifdef CONFIG_SERIAL_8250_AU1X00
+       case UPIO_AU:
+               __raw_writel(value, up->port.membase + offset);
+               break;
+#endif
+
        default:
                outb(value, up->port.iobase + offset);
        }
@@ -910,6 +965,13 @@ static void autoconfig(struct uart_8250_port *up, unsigned int probeflags)
                }
        }
 #endif
+
+#ifdef CONFIG_SERIAL_8250_AU1X00
+       /* if access method is AU, it is a 16550 with a quirk */
+       if (up->port.type == PORT_16550A && up->port.iotype == UPIO_AU)
+               up->bugs |= UART_BUG_NOMSR;
+#endif
+
        serial_outp(up, UART_LCR, save_lcr);
 
        if (up->capabilities != uart_config[up->port.type].flags) {
@@ -1057,6 +1119,10 @@ static void serial8250_enable_ms(struct uart_port *port)
 {
        struct uart_8250_port *up = (struct uart_8250_port *)port;
 
+       /* no MSR capabilities */
+       if (up->bugs & UART_BUG_NOMSR)
+               return;
+
        up->ier |= UART_IER_MSI;
        serial_out(up, UART_IER, up->ier);
 }
@@ -1774,7 +1840,8 @@ serial8250_set_termios(struct uart_port *port, struct termios *termios,
         * CTS flow control flag and modem status interrupts
         */
        up->ier &= ~UART_IER_MSI;
-       if (UART_ENABLE_MS(&up->port, termios->c_cflag))
+       if (!(up->bugs & UART_BUG_NOMSR) &&
+                       UART_ENABLE_MS(&up->port, termios->c_cflag))
                up->ier |= UART_IER_MSI;
        if (up->capabilities & UART_CAP_UUE)
                up->ier |= UART_IER_UUE | UART_IER_RTOIE;

diff --git a/drivers/serial/8250.h b/drivers/serial/8250.h
index b1b459e..a607b98 100644 (file)
--- a/drivers/serial/8250.h
+++ b/drivers/serial/8250.h
@@ -49,6 +49,7 @@ struct serial8250_config {
 
 #define UART_BUG_QUOT  (1 << 0)        /* UART has buggy quot LSB */
 #define UART_BUG_TXEN  (1 << 1)        /* UART has buggy TX IIR status */
+#define UART_BUG_NOMSR (1 << 2)        /* UART has buggy MSR status bits (Au1x00) */
 
 #if defined(__i386__) && (defined(CONFIG_M386) || defined(CONFIG_M486))
 #define _INLINE_ inline

diff --git a/drivers/serial/8250_au1x00.c b/drivers/serial/8250_au1x00.c
new file mode 100644 (file)
index 0000000..06ae8fb
--- /dev/null
+++ b/drivers/serial/8250_au1x00.c
@@ -0,0 +1,102 @@
+/*
+ * Serial Device Initialisation for Au1x00
+ *
+ * (C) Copyright Embedded Alley Solutions, Inc 2005
+ * Author: Pantelis Antoniou <pantelis@embeddedalley.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/ioport.h>
+#include <linux/module.h>
+#include <linux/serial_core.h>
+#include <linux/signal.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+
+#include <linux/serial_8250.h>
+
+#include <asm/mach-au1x00/au1000.h>
+
+#include "8250.h"
+
+#define PORT(_base, _irq)                              \
+       {                                               \
+               .iobase         = _base,                \
+               .membase        = (void __iomem *)_base,\
+               .mapbase        = _base,                \
+               .irq            = _irq,                 \
+               .uartclk        = 0,    /* filled */    \
+               .regshift       = 2,                    \
+               .iotype         = UPIO_AU,              \
+               .flags          = UPF_SKIP_TEST |       \
+                                 UPF_IOREMAP,          \
+       }
+
+static struct plat_serial8250_port au1x00_data[] = {
+#if defined(CONFIG_SOC_AU1000)
+       PORT(UART0_ADDR, AU1000_UART0_INT),
+       PORT(UART1_ADDR, AU1000_UART1_INT),
+       PORT(UART2_ADDR, AU1000_UART2_INT),
+       PORT(UART3_ADDR, AU1000_UART3_INT),
+#elif defined(CONFIG_SOC_AU1500)
+       PORT(UART0_ADDR, AU1500_UART0_INT),
+       PORT(UART3_ADDR, AU1500_UART3_INT),
+#elif defined(CONFIG_SOC_AU1100)
+       PORT(UART0_ADDR, AU1100_UART0_INT),
+       PORT(UART1_ADDR, AU1100_UART1_INT),
+       PORT(UART2_ADDR, AU1100_UART2_INT),
+       PORT(UART3_ADDR, AU1100_UART3_INT),
+#elif defined(CONFIG_SOC_AU1550)
+       PORT(UART0_ADDR, AU1550_UART0_INT),
+       PORT(UART1_ADDR, AU1550_UART1_INT),
+       PORT(UART2_ADDR, AU1550_UART2_INT),
+       PORT(UART3_ADDR, AU1550_UART3_INT),
+#elif defined(CONFIG_SOC_AU1200)
+       PORT(UART0_ADDR, AU1200_UART0_INT),
+       PORT(UART1_ADDR, AU1200_UART1_INT),
+#endif
+       { },
+};
+
+static struct platform_device au1x00_device = {
+       .name                   = "serial8250",
+       .id                     = PLAT8250_DEV_AU1X00,
+       .dev                    = {
+               .platform_data  = au1x00_data,
+       },
+};
+
+static int __init au1x00_init(void)
+{
+       int i;
+       unsigned int uartclk;
+
+       /* get uart clock */
+       uartclk = get_au1x00_uart_baud_base() * 16;
+
+       /* fill up uartclk */
+       for (i = 0; au1x00_data[i].flags ; i++)
+               au1x00_data[i].uartclk = uartclk;
+
+       return platform_device_register(&au1x00_device);
+}
+
+/* XXX: Yes, I know this doesn't yet work. */
+static void __exit au1x00_exit(void)
+{
+       platform_device_unregister(&au1x00_device);
+}
+
+module_init(au1x00_init);
+module_exit(au1x00_exit);
+
+MODULE_AUTHOR("Pantelis Antoniou <pantelis@embeddedalley.com>");
+MODULE_DESCRIPTION("8250 serial probe module for Au1x000 cards");
+MODULE_LICENSE("GPL");

diff --git a/drivers/serial/Kconfig b/drivers/serial/Kconfig
index b745a1b..ff36f0c 100644 (file)
--- a/drivers/serial/Kconfig
+++ b/drivers/serial/Kconfig
@@ -207,6 +207,14 @@ config SERIAL_8250_ACORN
          system, say Y to this option.  The driver can handle 1, 2, or 3 port
          cards.  If unsure, say N.
 
+config SERIAL_8250_AU1X00
+       bool "AU1X00 serial port support"
+       depends on SERIAL_8250 != n && SOC_AU1X00
+       help
+         If you have an Au1x00 board and want to use the serial port, say Y
+         to this option.  The driver can handle 1 or 2 serial ports.
+         If unsure, say N.
+
 comment "Non-8250 serial port support"
 
 config SERIAL_AMBA_PL010

diff --git a/drivers/serial/Makefile b/drivers/serial/Makefile
index 11c7dc4..d7c7c71 100644 (file)
--- a/drivers/serial/Makefile
+++ b/drivers/serial/Makefile
@@ -22,6 +22,7 @@ obj-$(CONFIG_SERIAL_8250_ACCENT) += 8250_accent.o
 obj-$(CONFIG_SERIAL_8250_BOCA) += 8250_boca.o
 obj-$(CONFIG_SERIAL_8250_HUB6) += 8250_hub6.o
 obj-$(CONFIG_SERIAL_8250_MCA) += 8250_mca.o
+obj-$(CONFIG_SERIAL_8250_AU1X00) += 8250_au1x00.o
 obj-$(CONFIG_SERIAL_AMBA_PL010) += amba-pl010.o
 obj-$(CONFIG_SERIAL_AMBA_PL011) += amba-pl011.o
 obj-$(CONFIG_SERIAL_CLPS711X) += clps711x.o

diff --git a/drivers/serial/serial_core.c b/drivers/serial/serial_core.c
index 0745ce7..427a238 100644 (file)
--- a/drivers/serial/serial_core.c
+++ b/drivers/serial/serial_core.c
@@ -1959,6 +1959,7 @@ uart_report_port(struct uart_driver *drv, struct uart_port *port)
                break;
        case UPIO_MEM:
        case UPIO_MEM32:
+       case UPIO_AU:
                snprintf(address, sizeof(address),
                         "MMIO 0x%lx", port->mapbase);
                break;

diff --git a/include/linux/serial_8250.h b/include/linux/serial_8250.h
index 2b799d4..cee302a 100644 (file)
--- a/include/linux/serial_8250.h
+++ b/include/linux/serial_8250.h
@@ -42,6 +42,7 @@ enum {
        PLAT8250_DEV_BOCA,
        PLAT8250_DEV_HUB6,
        PLAT8250_DEV_MCA,
+       PLAT8250_DEV_AU1X00,
 };
 
 /*

diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h
index 9d25792..a3ac92b 100644 (file)
--- a/include/linux/serial_core.h
+++ b/include/linux/serial_core.h
@@ -211,6 +211,7 @@ struct uart_port {
 #define UPIO_HUB6              (1)
 #define UPIO_MEM               (2)
 #define UPIO_MEM32             (3)
+#define UPIO_AU                        (4)                     /* Au1x00 type IO */
 
        unsigned int            read_status_mask;       /* driver specific */
        unsigned int            ignore_status_mask;     /* driver specific */