at91/bootiic/env_vars.c

/******************************************************************************
 *
 * Filename: env_vars.c
 *
 * Instantiation of environment variables, structures, and other globals.
 *
 * Revision information:
 *
 * 20AUG2004    kb_admin    initial creation
 *
 * BEGIN_KBDD_BLOCK
 * No warranty, expressed or implied, is included with this software.  It is
 * provided "AS IS" and no warranty of any kind including statutory or aspects
 * relating to merchantability or fitness for any purpose is provided.  All
 * intellectual property rights of others is maintained with the respective
 * owners.  This software is not copyrighted and is intended for reference
 * only.
 * END_BLOCK
 *
 * $FreeBSD$
 *****************************************************************************/

#include "env_vars.h"
#include "loader_prompt.h"
#include "lib.h"

/******************************* GLOBALS *************************************/
char    boot_commands[MAX_BOOT_COMMANDS][MAX_INPUT_SIZE];

char    env_table[MAX_ENV_SIZE_BYTES];

extern char BootCommandSection;

/************************** PRIVATE FUNCTIONS ********************************/


static int  currentIndex;
static int  currentOffset;


/*
 * .KB_C_FN_DEFINITION_START
 * int ReadCharFromEnvironment(char *)
 *  This private function reads characters from the enviroment variables
 * to service the command prompt during auto-boot or just to setup the
 * default environment.  Returns positive value if valid character was
 * set in the pointer.  Returns negative value to signal input stream
 * terminated.  Returns 0 to indicate _wait_ condition.
 * .KB_C_FN_DEFINITION_END
 */
static int
ReadCharFromEnvironment(int timeout)
{
    int ch;

    if (currentIndex < MAX_BOOT_COMMANDS) {
        ch = boot_commands[currentIndex][currentOffset++];
        if (ch == '\0' || (currentOffset >= MAX_INPUT_SIZE)) {
            currentOffset = 0;
            ++currentIndex;
            ch = '\r';
        }
        return (ch);
    }

    return (-1);
}


/*************************** GLOBAL FUNCTIONS ********************************/


/*
 * .KB_C_FN_DEFINITION_START
 * void WriteCommandTable(void)
 *  This global function write the current command table to the non-volatile
 * memory.
 * .KB_C_FN_DEFINITION_END
 */
void
WriteCommandTable(void)
{
    int i, size = MAX_ENV_SIZE_BYTES, copySize;
    char    *cPtr = env_table;

    p_memset(env_table, 0, sizeof(env_table));

    for (i = 0; i < MAX_BOOT_COMMANDS; ++i) {

        copySize = p_strlen(boot_commands[i]);
        size -= copySize + 1;

        if (size < 0) {
            continue;
        }
        memcpy(cPtr, boot_commands[i], copySize);
        cPtr += copySize;
        *cPtr++ = 0;
    }

    /* We're executing in low RAM so addr in ram == offset in eeprom */
    WriteEEPROM((unsigned)&BootCommandSection, env_table,
        sizeof(env_table));
}


/*
 * .KB_C_FN_DEFINITION_START
 * void SetBootCommand(int index, char *command)
 *  This global function replaces the specified index with the string residing
 * at command.  Execute this function with a NULL string to clear the
 * associated command index.
 * .KB_C_FN_DEFINITION_END
 */
void
SetBootCommand(int index, char *command)
{
    int     i;

    if ((unsigned)index < MAX_BOOT_COMMANDS) {

        p_memset(boot_commands[index], 0, MAX_INPUT_SIZE);

        if (!command)
            return ;

        for (i = 0; i < MAX_INPUT_SIZE; ++i) {
            boot_commands[index][i] = command[i];
            if (!(boot_commands[index][i]))
                return;
        }
    }
}


/*
 * .KB_C_FN_DEFINITION_START
 * void DumpBootCommands(void)
 *  This global function displays the current boot commands.
 * .KB_C_FN_DEFINITION_END
 */
void
DumpBootCommands(void)
{
    int i, j;

    for (i = 0; i < MAX_BOOT_COMMANDS; ++i) {
        printf("0x%x : ", i);
        for (j = 0; j < MAX_INPUT_SIZE; ++j) {
            putchar(boot_commands[i][j]);
            if (!(boot_commands[i][j]))
                break;
        }
        printf("[E]\n\r");
    }
}


/*
 * .KB_C_FN_DEFINITION_START
 * void LoadBootCommands(void)
 *  This global function loads the existing boot commands from raw format and
 * coverts it to the standard, command-index format.  Notice, the processed
 * boot command table has much more space allocated than the actual table
 * stored in non-volatile memory.  This is because the processed table
 * exists in RAM which is larger than the non-volatile space.
 * .KB_C_FN_DEFINITION_END
 */
void
LoadBootCommands(void)
{
    int index, j, size;
    char    *cPtr;

    p_memset((char*)boot_commands, 0, sizeof(boot_commands));

    cPtr = &BootCommandSection;

    size = MAX_ENV_SIZE_BYTES;

    for (index = 0; (index < MAX_BOOT_COMMANDS) && size; ++index) {
        for (j = 0; (j < MAX_INPUT_SIZE) && size; ++j) {
            size--;
            boot_commands[index][j] = *cPtr++;
            if (!(boot_commands[index][j])) {
                break;
            }
        }
    }
}


/*
 * .KB_C_FN_DEFINITION_START
 * void ExecuteEnvironmentFunctions(void)
 *  This global function executes applicable entries in the environment.
 * .KB_C_FN_DEFINITION_END
 */
void
ExecuteEnvironmentFunctions(void)
{
    currentIndex = 0;
    currentOffset = 0;

    DumpBootCommands();
    Bootloader(ReadCharFromEnvironment);
}