lwmon.c

嵌入式试验箱S3C2410的bootloader源代码

D* Design:       [e-mail]
C* Coding:       [e-mail]
V* Verification: [e-mail]
 ***********************************************************************/
int board_early_init_f (void)
{
	volatile immap_t *immr = (immap_t *) CFG_IMMR;

	/* Disable Ethernet TENA on Port B
	 * Necessary because of pull up in COM3 port.
	 *
	 * This is just a preliminary fix, intended to turn off TENA
	 * as soon as possible to avoid noise on the network. Once
	 * I睠 is running we will make sure the interface is
	 * correctly initialized.
	 */
	immr->im_cpm.cp_pbpar &= ~PB_ENET_TENA;
	immr->im_cpm.cp_pbodr &= ~PB_ENET_TENA;
	immr->im_cpm.cp_pbdat &= ~PB_ENET_TENA;	/* set to 0 = disabled */
	immr->im_cpm.cp_pbdir |= PB_ENET_TENA;

	return (0);
}

/* ------------------------------------------------------------------------- */

/***********************************************************************
F* Function:     void reset_phy (void) P*A*Z*
 *
P* Parameters:   none
P*
P* Returnvalue:  none
 *
Z* Intention:    Reset the PHY.  In the lwmon case we do this by the
Z*               signaling the PIC I/O expander.
 *
D* Design:       [e-mail]
C* Coding:       [e-mail]
V* Verification: [e-mail]
 ***********************************************************************/
void reset_phy (void)
{
	uchar c;

#ifdef DEBUG
	printf ("### Switch on Ethernet for SCC2 ###\n");
#endif
	c = pic_read (0x61);
#ifdef DEBUG
	printf ("Old PIC read: reg_61 = 0x%02x\n", c);
#endif
	c |= 0x40;					/* disable COM3 */
	c &= ~0x80;					/* enable Ethernet */
	pic_write (0x61, c);
#ifdef DEBUG
	c = pic_read (0x61);
	printf ("New PIC read: reg_61 = 0x%02x\n", c);
#endif
	udelay (1000);
}


/*------------------------- Keyboard controller -----------------------*/
/* command codes */
#define	KEYBD_CMD_READ_KEYS	0x01
#define KEYBD_CMD_READ_VERSION	0x02
#define KEYBD_CMD_READ_STATUS	0x03
#define KEYBD_CMD_RESET_ERRORS	0x10

/* status codes */
#define KEYBD_STATUS_MASK	0x3F
#define	KEYBD_STATUS_H_RESET	0x20
#define KEYBD_STATUS_BROWNOUT	0x10
#define KEYBD_STATUS_WD_RESET	0x08
#define KEYBD_STATUS_OVERLOAD	0x04
#define KEYBD_STATUS_ILLEGAL_WR	0x02
#define KEYBD_STATUS_ILLEGAL_RD	0x01

/* Number of bytes returned from Keyboard Controller */
#define KEYBD_VERSIONLEN	2	/* version information */
#define	KEYBD_DATALEN		9	/* normal key scan data */

/* maximum number of "magic" key codes that can be assigned */

static uchar kbd_addr = CFG_I2C_KEYBD_ADDR;

static uchar *key_match (uchar *);

#define	KEYBD_SET_DEBUGMODE	'#'	/* Magic key to enable debug output */

/***********************************************************************
F* Function:     int board_postclk_init (void) P*A*Z*
 *
P* Parameters:   none
P*
P* Returnvalue:  int
P*                - 0 is always returned.
 *
Z* Intention:    This function is the board_postclk_init() method implementation
Z*               for the lwmon board.
 *
 ***********************************************************************/
int board_postclk_init (void)
{
	kbd_init();

#ifdef CONFIG_MODEM_SUPPORT
	if (key_pressed()) {
		disable_putc();	/* modem doesn't understand banner etc */
		gd->do_mdm_init = 1;
	}
#endif

	return (0);
}

struct serial_device * default_serial_console (void)
{
	return gd->do_mdm_init ? &serial_scc_device : &serial_smc_device;
}

static void kbd_init (void)
{
	uchar kbd_data[KEYBD_DATALEN];
	uchar tmp_data[KEYBD_DATALEN];
	uchar val, errcd;
	int i;

	i2c_init (CFG_I2C_SPEED, CFG_I2C_SLAVE);

	gd->kbd_status = 0;

	/* Forced by PIC. Delays <= 175us loose */
	udelay(1000);

	/* Read initial keyboard error code */
	val = KEYBD_CMD_READ_STATUS;
	i2c_write (kbd_addr, 0, 0, &val, 1);
	i2c_read (kbd_addr, 0, 0, &errcd, 1);
	/* clear unused bits */
	errcd &= KEYBD_STATUS_MASK;
	/* clear "irrelevant" bits. Recommended by Martin Rajek, LWN */
	errcd &= ~(KEYBD_STATUS_H_RESET|KEYBD_STATUS_BROWNOUT);
	if (errcd) {
		gd->kbd_status |= errcd << 8;
	}
	/* Reset error code and verify */
	val = KEYBD_CMD_RESET_ERRORS;
	i2c_write (kbd_addr, 0, 0, &val, 1);
	udelay(1000);	/* delay NEEDED by keyboard PIC !!! */

	val = KEYBD_CMD_READ_STATUS;
	i2c_write (kbd_addr, 0, 0, &val, 1);
	i2c_read (kbd_addr, 0, 0, &val, 1);

	val &= KEYBD_STATUS_MASK;	/* clear unused bits */
	if (val) {			/* permanent error, report it */
		gd->kbd_status |= val;
		return;
	}

	/*
	 * Read current keyboard state.
	 *
	 * After the error reset it may take some time before the
	 * keyboard PIC picks up a valid keyboard scan - the total
	 * scan time is approx. 1.6 ms (information by Martin Rajek,
	 * 28 Sep 2002). We read a couple of times for the keyboard
	 * to stabilize, using a big enough delay.
	 * 10 times should be enough. If the data is still changing,
	 * we use what we get :-(
	 */

	memset (tmp_data, 0xFF, KEYBD_DATALEN);	/* impossible value */
	for (i=0; i<10; ++i) {
		val = KEYBD_CMD_READ_KEYS;
		i2c_write (kbd_addr, 0, 0, &val, 1);
		i2c_read (kbd_addr, 0, 0, kbd_data, KEYBD_DATALEN);

		if (memcmp(kbd_data, tmp_data, KEYBD_DATALEN) == 0) {
			/* consistent state, done */
			break;
		}
		/* remeber last state, delay, and retry */
		memcpy (tmp_data, kbd_data, KEYBD_DATALEN);
		udelay (5000);
	}
}

/***********************************************************************
F* Function:     int misc_init_r (void) P*A*Z*
 *
P* Parameters:   none
P*
P* Returnvalue:  int
P*                - 0 is always returned, even in the case of a keyboard
P*                    error.
 *
Z* Intention:    This function is the misc_init_r() method implementation
Z*               for the lwmon board.
Z*               The keyboard controller is initialized and the result
Z*               of a read copied to the environment variable "keybd".
Z*               If KEYBD_SET_DEBUGMODE is defined, a check is made for
Z*               this key, and if found display to the LCD will be enabled.
Z*               The keys in "keybd" are checked against the magic
Z*               keycommands defined in the environment.
Z*               See also key_match().
 *
D* Design:       [e-mail]
C* Coding:       [e-mail]
V* Verification: [e-mail]
 ***********************************************************************/
int misc_init_r (void)
{
	uchar kbd_data[KEYBD_DATALEN];
	char keybd_env[2 * KEYBD_DATALEN + 1];
	uchar kbd_init_status = gd->kbd_status >> 8;
	uchar kbd_status = gd->kbd_status;
	uchar val;
	char *str;
	int i;

	if (kbd_init_status) {
		printf ("KEYBD: Error %02X\n", kbd_init_status);
	}
	if (kbd_status) {		/* permanent error, report it */
		printf ("*** Keyboard error code %02X ***\n", kbd_status);
		sprintf (keybd_env, "%02X", kbd_status);
		setenv ("keybd", keybd_env);
		return 0;
	}

	/*
	 * Now we know that we have a working  keyboard,  so  disable
	 * all output to the LCD except when a key press is detected.
	 */

	if ((console_assign (stdout, "serial") < 0) ||
		(console_assign (stderr, "serial") < 0)) {
		printf ("Can't assign serial port as output device\n");
	}

	/* Read Version */
	val = KEYBD_CMD_READ_VERSION;
	i2c_write (kbd_addr, 0, 0, &val, 1);
	i2c_read (kbd_addr, 0, 0, kbd_data, KEYBD_VERSIONLEN);
	printf ("KEYBD: Version %d.%d\n", kbd_data[0], kbd_data[1]);

	/* Read current keyboard state */
	val = KEYBD_CMD_READ_KEYS;
	i2c_write (kbd_addr, 0, 0, &val, 1);
	i2c_read (kbd_addr, 0, 0, kbd_data, KEYBD_DATALEN);

	for (i = 0; i < KEYBD_DATALEN; ++i) {
		sprintf (keybd_env + i + i, "%02X", kbd_data[i]);
	}
	setenv ("keybd", keybd_env);

	str = strdup ((char *)key_match (kbd_data));	/* decode keys */
#ifdef KEYBD_SET_DEBUGMODE
	if (kbd_data[0] == KEYBD_SET_DEBUGMODE) {	/* set debug mode */
		if ((console_assign (stdout, "lcd") < 0) ||
			(console_assign (stderr, "lcd") < 0)) {
			printf ("Can't assign LCD display as output device\n");
		}
	}
#endif /* KEYBD_SET_DEBUGMODE */
#ifdef CONFIG_PREBOOT	/* automatically configure "preboot" command on key match */
	setenv ("preboot", str);	/* set or delete definition */
#endif /* CONFIG_PREBOOT */
	if (str != NULL) {
		free (str);
	}
	return (0);
}

#ifdef CONFIG_PREBOOT

static uchar kbd_magic_prefix[] = "key_magic";
static uchar kbd_command_prefix[] = "key_cmd";

static int compare_magic (uchar *kbd_data, uchar *str)
{
	uchar compare[KEYBD_DATALEN-1];
	char *nxt;
	int i;

	/* Don't include modifier byte */
	memcpy (compare, kbd_data+1, KEYBD_DATALEN-1);

	for (; str != NULL; str = (*nxt) ? (uchar *)(nxt+1) : (uchar *)nxt) {
		uchar c;
		int k;

		c = (uchar) simple_strtoul ((char *)str, (char **) (&nxt), 16);

		if (str == (uchar *)nxt) {	/* invalid character */
			break;
		}

		/*
		 * Check if this key matches the input.
		 * Set matches to zero, so they match only once
		 * and we can find duplicates or extra keys
		 */
		for (k = 0; k < sizeof(compare); ++k) {
			if (compare[k] == '\0')	/* only non-zero entries */
				continue;
			if (c == compare[k]) {	/* found matching key */
				compare[k] = '\0';
				break;
			}
		}
		if (k == sizeof(compare)) {
			return -1;		/* unmatched key */
		}
	}

	/*
	 * A full match leaves no keys in the `compare' array,
	 */
	for (i = 0; i < sizeof(compare); ++i) {
		if (compare[i])
		{
			return -1;
		}
	}

	return 0;
}

/***********************************************************************
F* Function:     static uchar *key_match (uchar *kbd_data) P*A*Z*
 *
P* Parameters:   uchar *kbd_data
P*                - The keys to match against our magic definitions
P*
P* Returnvalue:  uchar *
P*                - != NULL: Pointer to the corresponding command(s)
P*                     NULL: No magic is about to happen
 *
Z* Intention:    Check if pressed key(s) match magic sequence,
Z*               and return the command string associated with that key(s).
Z*
Z*               If no key press was decoded, NULL is returned.
Z*
Z*               Note: the first character of the argument will be
Z*                     overwritten with the "magic charcter code" of the
Z*                     decoded key(s), or '\0'.
Z*
Z*               Note: the string points to static environment data
Z*                     and must be saved before you call any function that
Z*                     modifies the environment.
 *
D* Design:       [e-mail]