8250_hp300.c

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/*
 * Driver for the 98626/98644/internal serial interface on hp300/hp400
 * (based on the National Semiconductor INS8250/NS16550AF/WD16C552 UARTs)
 *
 * Ported from 2.2 and modified to use the normal 8250 driver
 * by Kars de Jong <[email protected]>, May 2004.
 */
#include <linux/module.h>
#include <linux/init.h>
#include <linux/string.h>
#include <linux/kernel.h>
#include <linux/serial.h>
#include <linux/serial_core.h>
#include <linux/serial_8250.h>
#include <linux/delay.h>
#include <linux/dio.h>
#include <linux/console.h>
#include <linux/slab.h>
#include <asm/io.h>

#include "8250.h"

#if !defined(CONFIG_HPDCA) && !defined(CONFIG_HPAPCI)
#warning CONFIG_8250 defined but neither CONFIG_HPDCA nor CONFIG_HPAPCI defined, are you sure?
#endif

#ifdef CONFIG_HPAPCI
struct hp300_port
{
    struct hp300_port *next;    /* next port */
    int line;           /* line (tty) number */
};

static struct hp300_port *hp300_ports;
#endif

#ifdef CONFIG_HPDCA

static int __devinit hpdca_init_one(struct dio_dev *d,
                    const struct dio_device_id *ent);
static void __devexit hpdca_remove_one(struct dio_dev *d);

static struct dio_device_id hpdca_dio_tbl[] = {
    { DIO_ID_DCA0 },
    { DIO_ID_DCA0REM },
    { DIO_ID_DCA1 },
    { DIO_ID_DCA1REM },
    { 0 }
};

static struct dio_driver hpdca_driver = {
    .name      = "hpdca",
    .id_table  = hpdca_dio_tbl,
    .probe     = hpdca_init_one,
    .remove    = __devexit_p(hpdca_remove_one),
};

#endif

static unsigned int num_ports;

extern int hp300_uart_scode;

/* Offset to UART registers from base of DCA */
#define UART_OFFSET 17

#define DCA_ID      0x01    /* ID (read), reset (write) */
#define DCA_IC      0x03    /* Interrupt control        */

/* Interrupt control */
#define DCA_IC_IE   0x80    /* Master interrupt enable  */

#define HPDCA_BAUD_BASE 153600

/* Base address of the Frodo part */
#define FRODO_BASE  (0x41c000)

/*
 * Where we find the 8250-like APCI ports, and how far apart they are.
 */
#define FRODO_APCIBASE      0x0
#define FRODO_APCISPACE     0x20
#define FRODO_APCI_OFFSET(x)    (FRODO_APCIBASE + ((x) * FRODO_APCISPACE))

#define HPAPCI_BAUD_BASE 500400

#ifdef CONFIG_SERIAL_8250_CONSOLE
/*
 * Parse the bootinfo to find descriptions for headless console and
 * debug serial ports and register them with the 8250 driver.
 * This function should be called before serial_console_init() is called
 * to make sure the serial console will be available for use. IA-64 kernel
 * calls this function from setup_arch() after the EFI and ACPI tables have
 * been parsed.
 */
int __init hp300_setup_serial_console(void)
{
    int scode;
    struct uart_port port;

    memset(&port, 0, sizeof(port));

    if (hp300_uart_scode < 0 || hp300_uart_scode > DIO_SCMAX)
        return 0;

    if (DIO_SCINHOLE(hp300_uart_scode))
        return 0;

    scode = hp300_uart_scode;

    /* Memory mapped I/O */
    port.iotype = UPIO_MEM;
    port.flags = UPF_SKIP_TEST | UPF_SHARE_IRQ | UPF_BOOT_AUTOCONF;
    port.type = PORT_UNKNOWN;

    /* Check for APCI console */
    if (scode == 256) {
#ifdef CONFIG_HPAPCI
        printk(KERN_INFO "Serial console is HP APCI 1\n");

        port.uartclk = HPAPCI_BAUD_BASE * 16;
        port.mapbase = (FRODO_BASE + FRODO_APCI_OFFSET(1));
        port.membase = (char *)(port.mapbase + DIO_VIRADDRBASE);
        port.regshift = 2;
        add_preferred_console("ttyS", port.line, "9600n8");
#else
        printk(KERN_WARNING "Serial console is APCI but support is disabled (CONFIG_HPAPCI)!\n");
        return 0;
#endif
    } else {
#ifdef CONFIG_HPDCA
        unsigned long pa = dio_scodetophysaddr(scode);
        if (!pa)
            return 0;

        printk(KERN_INFO "Serial console is HP DCA at select code %d\n", scode);

        port.uartclk = HPDCA_BAUD_BASE * 16;
        port.mapbase = (pa + UART_OFFSET);
        port.membase = (char *)(port.mapbase + DIO_VIRADDRBASE);
        port.regshift = 1;
        port.irq = DIO_IPL(pa + DIO_VIRADDRBASE);

        /* Enable board-interrupts */
        out_8(pa + DIO_VIRADDRBASE + DCA_IC, DCA_IC_IE);

        if (DIO_ID(pa + DIO_VIRADDRBASE) & 0x80)
            add_preferred_console("ttyS", port.line, "9600n8");
#else
        printk(KERN_WARNING "Serial console is DCA but support is disabled (CONFIG_HPDCA)!\n");
        return 0;
#endif
    }

    if (early_serial_setup(&port) < 0)
        printk(KERN_WARNING "hp300_setup_serial_console(): early_serial_setup() failed.\n");
    return 0;
}
#endif /* CONFIG_SERIAL_8250_CONSOLE */

#ifdef CONFIG_HPDCA
static int __devinit hpdca_init_one(struct dio_dev *d,
                const struct dio_device_id *ent)
{
    struct uart_8250_port uart;
    int line;

#ifdef CONFIG_SERIAL_8250_CONSOLE
    if (hp300_uart_scode == d->scode) {
        /* Already got it. */
        return 0;
    }
#endif
    memset(&uart, 0, sizeof(uart));

    /* Memory mapped I/O */
    uart.port.iotype = UPIO_MEM;
    uart.port.flags = UPF_SKIP_TEST | UPF_SHARE_IRQ | UPF_BOOT_AUTOCONF;
    uart.port.irq = d->ipl;
    uart.port.uartclk = HPDCA_BAUD_BASE * 16;
    uart.port.mapbase = (d->resource.start + UART_OFFSET);
    uart.port.membase = (char *)(uart.port.mapbase + DIO_VIRADDRBASE);
    uart.port.regshift = 1;
    uart.port.dev = &d->dev;
    line = serial8250_register_8250_port(&uart);

    if (line < 0) {
        printk(KERN_NOTICE "8250_hp300: register_serial() DCA scode %d"
               " irq %d failed\n", d->scode, uart.port.irq);
        return -ENOMEM;
    }

    /* Enable board-interrupts */
    out_8(d->resource.start + DIO_VIRADDRBASE + DCA_IC, DCA_IC_IE);
    dio_set_drvdata(d, (void *)line);

    /* Reset the DCA */
    out_8(d->resource.start + DIO_VIRADDRBASE + DCA_ID, 0xff);
    udelay(100);

    num_ports++;

    return 0;
}
#endif

static int __init hp300_8250_init(void)
{
    static int called;
#ifdef CONFIG_HPAPCI
    int line;
    unsigned long base;
    struct uart_8250_port uart;
    struct hp300_port *port;
    int i;
#endif
    if (called)
        return -ENODEV;
    called = 1;

    if (!MACH_IS_HP300)
        return -ENODEV;

#ifdef CONFIG_HPDCA
    dio_register_driver(&hpdca_driver);
#endif
#ifdef CONFIG_HPAPCI
    if (hp300_model < HP_400) {
        if (!num_ports)
            return -ENODEV;
        return 0;
    }
    /* These models have the Frodo chip.
     * Port 0 is reserved for the Apollo Domain keyboard.
     * Port 1 is either the console or the DCA.
     */
    for (i = 1; i < 4; i++) {
        /* Port 1 is the console on a 425e, on other machines it's
         * mapped to DCA.
         */
#ifdef CONFIG_SERIAL_8250_CONSOLE
        if (i == 1)
            continue;
#endif

        /* Create new serial device */
        port = kmalloc(sizeof(struct hp300_port), GFP_KERNEL);
        if (!port)
            return -ENOMEM;

        memset(&uart, 0, sizeof(uart));

        base = (FRODO_BASE + FRODO_APCI_OFFSET(i));

        /* Memory mapped I/O */
        uart.port.iotype = UPIO_MEM;
        uart.port.flags = UPF_SKIP_TEST | UPF_SHARE_IRQ \
                  | UPF_BOOT_AUTOCONF;
        /* XXX - no interrupt support yet */
        uart.port.irq = 0;
        uart.port.uartclk = HPAPCI_BAUD_BASE * 16;
        uart.port.mapbase = base;
        uart.port.membase = (char *)(base + DIO_VIRADDRBASE);
        uart.port.regshift = 2;

        line = serial8250_register_8250_port(&uart);

        if (line < 0) {
            printk(KERN_NOTICE "8250_hp300: register_serial() APCI"
                   " %d irq %d failed\n", i, uart.port.irq);
            kfree(port);
            continue;
        }

        port->line = line;
        port->next = hp300_ports;
        hp300_ports = port;

        num_ports++;
    }
#endif

    /* Any boards found? */
    if (!num_ports)
        return -ENODEV;

    return 0;
}

#ifdef CONFIG_HPDCA
static void __devexit hpdca_remove_one(struct dio_dev *d)
{
    int line;

    line = (int) dio_get_drvdata(d);
    if (d->resource.start) {
        /* Disable board-interrupts */
        out_8(d->resource.start + DIO_VIRADDRBASE + DCA_IC, 0);
    }
    serial8250_unregister_port(line);
}
#endif

static void __exit hp300_8250_exit(void)
{
#ifdef CONFIG_HPAPCI
    struct hp300_port *port, *to_free;

    for (port = hp300_ports; port; ) {
        serial8250_unregister_port(port->line);
        to_free = port;
        port = port->next;
        kfree(to_free);
    }

    hp300_ports = NULL;
#endif
#ifdef CONFIG_HPDCA
    dio_unregister_driver(&hpdca_driver);
#endif
}

module_init(hp300_8250_init);
module_exit(hp300_8250_exit);
MODULE_DESCRIPTION("HP DCA/APCI serial driver");
MODULE_AUTHOR("Kars de Jong <[email protected]>");
MODULE_LICENSE("GPL");