prom.c

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/*
 * Carsten Langgaard, [email protected]
 * Copyright (C) 1999,2000 MIPS Technologies, Inc.  All rights reserved.
 *
 *  This program is free software; you can distribute it and/or modify it
 *  under the terms of the GNU General Public License (Version 2) as
 *  published by the Free Software Foundation.
 *
 *  This program is distributed in the hope it will be useful, but WITHOUT
 *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 *  for more details.
 *
 *  You should have received a copy of the GNU General Public License along
 *  with this program; if not, write to the Free Software Foundation, Inc.,
 *  59 Temple Place - Suite 330, Boston MA 02111-1307, USA.
 *
 * Putting things on the screen/serial line using YAMONs facilities.
 */
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/serial_reg.h>
#include <linux/spinlock.h>
#include <linux/module.h>
#include <linux/string.h>
#include <linux/io.h>
#include <asm/bootinfo.h>

#include <asm/mach-ar7/ar7.h>
#include <asm/mach-ar7/prom.h>

#define MAX_ENTRY 80

struct env_var {
    char    *name;
    char    *value;
};

static struct env_var adam2_env[MAX_ENTRY];

char *prom_getenv(const char *name)
{
    int i;

    for (i = 0; (i < MAX_ENTRY) && adam2_env[i].name; i++)
        if (!strcmp(name, adam2_env[i].name))
            return adam2_env[i].value;

    return NULL;
}
EXPORT_SYMBOL(prom_getenv);

static void  __init ar7_init_cmdline(int argc, char *argv[])
{
    int i;

    for (i = 1; i < argc; i++) {
        strlcat(arcs_cmdline, argv[i], COMMAND_LINE_SIZE);
        if (i < (argc - 1))
            strlcat(arcs_cmdline, " ", COMMAND_LINE_SIZE);
    }
}

struct psbl_rec {
    u32 psbl_size;
    u32 env_base;
    u32 env_size;
    u32 ffs_base;
    u32 ffs_size;
};

static const char psp_env_version[] __initconst = "TIENV0.8";

struct psp_env_chunk {
    u8  num;
    u8  ctrl;
    u16 csum;
    u8  len;
    char    data[11];
} __packed;

struct psp_var_map_entry {
    u8  num;
    char    *value;
};

static const struct psp_var_map_entry psp_var_map[] = {
    {  1,   "cpufrequency" },
    {  2,   "memsize" },
    {  3,   "flashsize" },
    {  4,   "modetty0" },
    {  5,   "modetty1" },
    {  8,   "maca" },
    {  9,   "macb" },
    { 28,   "sysfrequency" },
    { 38,   "mipsfrequency" },
};

/*

Well-known variable (num is looked up in table above for matching variable name)
Example: cpufrequency=211968000
+----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+---
| 01 |CTRL|CHECKSUM | 01 | _2 | _1 | _1 | _9 | _6 | _8 | _0 | _0 | _0 | \0 | FF
+----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+---

Name=Value pair in a single chunk
Example: NAME=VALUE
+----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+---
| 00 |CTRL|CHECKSUM | 01 | _N | _A | _M | _E | _0 | _V | _A | _L | _U | _E | \0
+----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+---

Name=Value pair in 2 chunks (len is the number of chunks)
Example: bootloaderVersion=1.3.7.15
+----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+---
| 00 |CTRL|CHECKSUM | 02 | _b | _o | _o | _t | _l | _o | _a | _d | _e | _r | _V
+----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+---
| _e | _r | _s | _i | _o | _n | \0 | _1 | _. | _3 | _. | _7 | _. | _1 | _5 | \0
+----+----+----+----+----+----+----+----+----+----+----+----+----+----+----+---

Data is padded with 0xFF

*/

#define PSP_ENV_SIZE  4096

static char psp_env_data[PSP_ENV_SIZE] = { 0, };

static char * __init lookup_psp_var_map(u8 num)
{
    int i;

    for (i = 0; i < ARRAY_SIZE(psp_var_map); i++)
        if (psp_var_map[i].num == num)
            return psp_var_map[i].value;

    return NULL;
}

static void __init add_adam2_var(char *name, char *value)
{
    int i;

    for (i = 0; i < MAX_ENTRY; i++) {
        if (!adam2_env[i].name) {
            adam2_env[i].name = name;
            adam2_env[i].value = value;
            return;
        } else if (!strcmp(adam2_env[i].name, name)) {
            adam2_env[i].value = value;
            return;
        }
    }
}

static int __init parse_psp_env(void *psp_env_base)
{
    int i, n;
    char *name, *value;
    struct psp_env_chunk *chunks = (struct psp_env_chunk *)psp_env_data;

    memcpy_fromio(chunks, psp_env_base, PSP_ENV_SIZE);

    i = 1;
    n = PSP_ENV_SIZE / sizeof(struct psp_env_chunk);
    while (i < n) {
        if ((chunks[i].num == 0xff) || ((i + chunks[i].len) > n))
            break;
        value = chunks[i].data;
        if (chunks[i].num) {
            name = lookup_psp_var_map(chunks[i].num);
        } else {
            name = value;
            value += strlen(name) + 1;
        }
        if (name)
            add_adam2_var(name, value);
        i += chunks[i].len;
    }
    return 0;
}

static void __init ar7_init_env(struct env_var *env)
{
    int i;
    struct psbl_rec *psbl = (struct psbl_rec *)(KSEG1ADDR(0x14000300));
    void *psp_env = (void *)KSEG1ADDR(psbl->env_base);

    if (strcmp(psp_env, psp_env_version) == 0) {
        parse_psp_env(psp_env);
    } else {
        for (i = 0; i < MAX_ENTRY; i++, env++)
            if (env->name)
                add_adam2_var(env->name, env->value);
    }
}

static void __init console_config(void)
{
#ifdef CONFIG_SERIAL_8250_CONSOLE
    char console_string[40];
    int baud = 0;
    char parity = '\0', bits = '\0', flow = '\0';
    char *s, *p;

    if (strstr(arcs_cmdline, "console="))
        return;

    s = prom_getenv("modetty0");
    if (s) {
        baud = simple_strtoul(s, &p, 10);
        s = p;
        if (*s == ',')
            s++;
        if (*s)
            parity = *s++;
        if (*s == ',')
            s++;
        if (*s)
            bits = *s++;
        if (*s == ',')
            s++;
        if (*s == 'h')
            flow = 'r';
    }

    if (baud == 0)
        baud = 38400;
    if (parity != 'n' && parity != 'o' && parity != 'e')
        parity = 'n';
    if (bits != '7' && bits != '8')
        bits = '8';

    if (flow == 'r')
        sprintf(console_string, " console=ttyS0,%d%c%c%c", baud,
            parity, bits, flow);
    else
        sprintf(console_string, " console=ttyS0,%d%c%c", baud, parity,
            bits);
    strlcat(arcs_cmdline, console_string, COMMAND_LINE_SIZE);
#endif
}

void __init prom_init(void)
{
    ar7_init_cmdline(fw_arg0, (char **)fw_arg1);
    ar7_init_env((struct env_var *)fw_arg2);
    console_config();

    ar7_gpio_init();
}

#define PORT(offset) (KSEG1ADDR(AR7_REGS_UART0 + (offset * 4)))
static inline unsigned int serial_in(int offset)
{
    return readl((void *)PORT(offset));
}

static inline void serial_out(int offset, int value)
{
    writel(value, (void *)PORT(offset));
}

int prom_putchar(char c)
{
    while ((serial_in(UART_LSR) & UART_LSR_TEMT) == 0)
        ;
    serial_out(UART_TX, c);
    return 1;
}