CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC
CONFIG_RTC_DS164x - use Dallas DS164x RTC
+ Note that if the RTC uses I2C, then the I2C interface
+ must also be configured. See I2C Support, below.
+
- Timestamp Support:
When CONFIG_TIMESTAMP is selected, the timestamp
- I2C Support: CONFIG_HARD_I2C | CONFIG_SOFT_I2C
- Enables I2C serial bus commands. If this is selected,
- either CONFIG_HARD_I2C or CONFIG_SOFT_I2C must be defined
- to include the appropriate I2C driver.
+ These enable I2C serial bus commands. Defining either of
+ (but not both of) CONFIG_HARD_I2C or CONFIG_SOFT_I2C will
+ include the appropriate I2C driver for the selected cpu.
- See also: common/cmd_i2c.c for a description of the
+ This will allow you to use i2c commands at the u-boot
+ command line (as long as you set CFG_CMD_I2C in
+ CONFIG_COMMANDS) and communicate with i2c based realtime
+ clock chips. See common/cmd_i2c.c for a description of the
command line interface.
+ CONFIG_HARD_I2C selects the CPM hardware driver for I2C.
+
+ CONFIG_SOFT_I2C configures u-boot to use a software (aka
+ bit-banging) driver instead of CPM or similar hardware
+ support for I2C.
- CONFIG_HARD_I2C
+ There are several other quantities that must also be
+ defined when you define CONFIG_HARD_I2C or CONFIG_SOFT_I2C.
- Selects the CPM hardware driver for I2C.
+ In both cases you will need to define CFG_I2C_SPEED
+ to be the frequency (in Hz) at which you wish your i2c bus
+ to run and CFG_I2C_SLAVE to be the address of this node (ie
+ the cpu's i2c node address).
+
+ Now, the u-boot i2c code for the mpc8xx (cpu/mpc8xx/i2c.c)
+ sets the cpu up as a master node and so its address should
+ therefore be cleared to 0 (See, eg, MPC823e User's Manual
+ p.16-473). So, set CFG_I2C_SLAVE to 0.
- CONFIG_SOFT_I2C
+ That's all that's required for CONFIG_HARD_I2C.
- Use software (aka bit-banging) driver instead of CPM
- or similar hardware support for I2C. This is configured
- via the following defines.
+ If you use the software i2c interface (CONFIG_SOFT_I2C)
+ then the following macros need to be defined (examples are
+ from include/configs/lwmon.h):
I2C_INIT
- (Optional). Any commands necessary to enable I2C
+ (Optional). Any commands necessary to enable the I2C
controller or configure ports.
+ eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL)
+
I2C_PORT
(Only for MPC8260 CPU). The I/O port to use (the code
(driven). If the data line is open collector, this
define can be null.
+ eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA)
+
I2C_TRISTATE
The code necessary to make the I2C data line tri-stated
(inactive). If the data line is open collector, this
define can be null.
+ eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
+
I2C_READ
Code that returns TRUE if the I2C data line is high,
FALSE if it is low.
+ eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
+
I2C_SDA(bit)
If <bit> is TRUE, sets the I2C data line high. If it
is FALSE, it clears it (low).
+ eg: #define I2C_SDA(bit) \
+ if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \
+ else immr->im_cpm.cp_pbdat &= ~PB_SDA
+
I2C_SCL(bit)
If <bit> is TRUE, sets the I2C clock line high. If it
is FALSE, it clears it (low).
+ eg: #define I2C_SCL(bit) \
+ if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \
+ else immr->im_cpm.cp_pbdat &= ~PB_SCL
+
I2C_DELAY
This delay is invoked four times per clock cycle so this
controls the rate of data transfer. The data rate thus
- is 1 / (I2C_DELAY * 4).
+ is 1 / (I2C_DELAY * 4). Often defined to be something
+ like:
+
+ #define I2C_DELAY udelay(2)
CFG_I2C_INIT_BOARD
void logbuff_init_ptrs (void)
{
DECLARE_GLOBAL_DATA_PTR;
+ unsigned long *ext_tag;
char *s;
log_buf = (unsigned char *)(gd->bd->bi_memsize-LOGBUFF_LEN);
- ext_log_start = (unsigned long *)(log_buf)-3;
+ ext_tag = (unsigned long *)(log_buf)-4;
+ ext_log_start = (unsigned long *)(log_buf)-3;
ext_log_size = (unsigned long *)(log_buf)-2;
ext_logged_chars = (unsigned long *)(log_buf)-1;
#ifdef CONFIG_POST
/* The post routines have setup the word so we can simply test it */
- if (post_word_load () & POST_POWERON) {
+ if ((post_word_load () & 0xffff) == POST_POWERON) {
logged_chars = log_size = log_start = 0;
+ *ext_tag = LOGBUFF_MAGIC;
}
#else
/* No post routines, so we do our own checking */
if (post_word_load () != LOGBUFF_MAGIC) {
logged_chars = log_size = log_start = 0;
post_word_store (LOGBUFF_MAGIC);
+ *ext_tag = LOGBUFF_MAGIC;
}
#endif
/* Initialize default loglevel if present */
if (strcmp(argv[1],"append") == 0) {
/* Log concatenation of all arguments separated by spaces */
for (i=2; i<argc; i++) {
- if (i<argc-1) {
- logbuff_printk (argv[i]);
- logbuff_putc (' ');
- } else {
- logbuff_puts (argv[i]);
- }
+ logbuff_printk (argv[i]);
+ logbuff_putc ((i<argc-1) ? ' ' : '\n');
}
return 0;
}
cmd_tbl_t U_BOOT_CMD(LOG) = MK_CMD_ENTRY(
"log", 255, 1, do_log,
"log - manipulate logbuffer\n",
- "log info - show pointer details\n"
+ "info - show pointer details\n"
"log reset - clear contents\n"
"log show - show contents\n"
"log append <msg> - append <msg> to the logbuffer\n"
projects / u-boot / commitdiff