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#include <console/console.h>
#include <pc80/mc146818rtc.h>
#include <boot/coreboot_tables.h>
#include <string.h>
#if CONFIG_USE_OPTION_TABLE
#include "option_table.h"
#endif
/* control registers - Moto names
*/
#define RTC_REG_A 10
#define RTC_REG_B 11
#define RTC_REG_C 12
#define RTC_REG_D 13
/**********************************************************************
* register details
**********************************************************************/
#define RTC_FREQ_SELECT RTC_REG_A
/* update-in-progress - set to "1" 244 microsecs before RTC goes off the bus,
* reset after update (may take 1.984ms @ 32768Hz RefClock) is complete,
* totalling to a max high interval of 2.228 ms.
*/
# define RTC_UIP 0x80
# define RTC_DIV_CTL 0x70
/* divider control: refclock values 4.194 / 1.049 MHz / 32.768 kHz */
# define RTC_REF_CLCK_4MHZ 0x00
# define RTC_REF_CLCK_1MHZ 0x10
# define RTC_REF_CLCK_32KHZ 0x20
/* 2 values for divider stage reset, others for "testing purposes only" */
# define RTC_DIV_RESET1 0x60
# define RTC_DIV_RESET2 0x70
/* Periodic intr. / Square wave rate select. 0=none, 1=32.8kHz,... 15=2Hz */
# define RTC_RATE_SELECT 0x0F
# define RTC_RATE_NONE 0x00
# define RTC_RATE_32786HZ 0x01
# define RTC_RATE_16384HZ 0x02
# define RTC_RATE_8192HZ 0x03
# define RTC_RATE_4096HZ 0x04
# define RTC_RATE_2048HZ 0x05
# define RTC_RATE_1024HZ 0x06
# define RTC_RATE_512HZ 0x07
# define RTC_RATE_256HZ 0x08
# define RTC_RATE_128HZ 0x09
# define RTC_RATE_64HZ 0x0a
# define RTC_RATE_32HZ 0x0b
# define RTC_RATE_16HZ 0x0c
# define RTC_RATE_8HZ 0x0d
# define RTC_RATE_4HZ 0x0e
# define RTC_RATE_2HZ 0x0f
/**********************************************************************/
#define RTC_CONTROL RTC_REG_B
# define RTC_SET 0x80 /* disable updates for clock setting */
# define RTC_PIE 0x40 /* periodic interrupt enable */
# define RTC_AIE 0x20 /* alarm interrupt enable */
# define RTC_UIE 0x10 /* update-finished interrupt enable */
# define RTC_SQWE 0x08 /* enable square-wave output */
# define RTC_DM_BINARY 0x04 /* all time/date values are BCD if clear */
# define RTC_24H 0x02 /* 24 hour mode - else hours bit 7 means pm */
# define RTC_DST_EN 0x01 /* auto switch DST - works f. USA only */
/**********************************************************************/
#define RTC_INTR_FLAGS RTC_REG_C
/* caution - cleared by read */
# define RTC_IRQF 0x80 /* any of the following 3 is active */
# define RTC_PF 0x40
# define RTC_AF 0x20
# define RTC_UF 0x10
/**********************************************************************/
#define RTC_VALID RTC_REG_D
# define RTC_VRT 0x80 /* valid RAM and time */
/**********************************************************************/
#if CONFIG_USE_OPTION_TABLE
static int rtc_checksum_valid(int range_start, int range_end, int cks_loc)
{
int i;
unsigned sum, old_sum;
sum = 0;
for(i = range_start; i <= range_end; i++) {
sum += cmos_read(i);
}
sum = (~sum)&0x0ffff;
old_sum = ((cmos_read(cks_loc)<<8) | cmos_read(cks_loc+1))&0x0ffff;
return sum == old_sum;
}
static void rtc_set_checksum(int range_start, int range_end, int cks_loc)
{
int i;
unsigned sum;
sum = 0;
for(i = range_start; i <= range_end; i++) {
sum += cmos_read(i);
}
sum = ~(sum & 0x0ffff);
cmos_write(((sum >> 8) & 0x0ff), cks_loc);
cmos_write(((sum >> 0) & 0x0ff), cks_loc+1);
}
#endif
#if CONFIG_ARCH_X86
#define RTC_CONTROL_DEFAULT (RTC_24H)
#define RTC_FREQ_SELECT_DEFAULT (RTC_REF_CLCK_32KHZ | RTC_RATE_1024HZ)
#else
#if CONFIG_ARCH_ALPHA
#define RTC_CONTROL_DEFAULT (RTC_SQWE | RTC_24H)
#define RTC_FREQ_SELECT_DEFAULT (RTC_REF_CLCK_32KHZ | RTC_RATE_1024HZ)
#endif
#endif
void rtc_init(int invalid)
{
#if CONFIG_USE_OPTION_TABLE
unsigned char x;
int cmos_invalid, checksum_invalid;
#endif
printk(BIOS_DEBUG, "RTC Init\n");
#if CONFIG_USE_OPTION_TABLE
/* See if there has been a CMOS power problem. */
x = cmos_read(RTC_VALID);
cmos_invalid = !(x & RTC_VRT);
/* See if there is a CMOS checksum error */
checksum_invalid = !rtc_checksum_valid(PC_CKS_RANGE_START,
PC_CKS_RANGE_END,PC_CKS_LOC);
if (invalid || cmos_invalid || checksum_invalid) {
printk(BIOS_WARNING, "RTC:%s%s%s zeroing cmos\n",
invalid?" Clear requested":"",
cmos_invalid?" Power Problem":"",
checksum_invalid?" Checksum invalid":"");
#if 0
cmos_write(0, 0x01);
cmos_write(0, 0x03);
cmos_write(0, 0x05);
for(i = 10; i < 48; i++) {
cmos_write(0, i);
}
if (cmos_invalid) {
/* Now setup a default date of Sat 1 January 2000 */
cmos_write(0, 0x00); /* seconds */
cmos_write(0, 0x02); /* minutes */
cmos_write(1, 0x04); /* hours */
cmos_write(7, 0x06); /* day of week */
cmos_write(1, 0x07); /* day of month */
cmos_write(1, 0x08); /* month */
cmos_write(0, 0x09); /* year */
}
#endif
}
#endif
/* Setup the real time clock */
cmos_write(RTC_CONTROL_DEFAULT, RTC_CONTROL);
/* Setup the frequency it operates at */
cmos_write(RTC_FREQ_SELECT_DEFAULT, RTC_FREQ_SELECT);
#if CONFIG_USE_OPTION_TABLE
/* See if there is a LB CMOS checksum error */
checksum_invalid = !rtc_checksum_valid(LB_CKS_RANGE_START,
LB_CKS_RANGE_END,LB_CKS_LOC);
if(checksum_invalid)
printk(BIOS_DEBUG, "Invalid CMOS LB checksum\n");
/* Make certain we have a valid checksum */
rtc_set_checksum(PC_CKS_RANGE_START,
PC_CKS_RANGE_END,PC_CKS_LOC);
#endif
/* Clear any pending interrupts */
(void) cmos_read(RTC_INTR_FLAGS);
}
#if CONFIG_USE_OPTION_TABLE
/* This routine returns the value of the requested bits
input bit = bit count from the beginning of the cmos image
length = number of bits to include in the value
ret = a character pointer to where the value is to be returned
output the value placed in ret
returns 0 = successful, -1 = an error occurred
*/
static int get_cmos_value(unsigned long bit, unsigned long length, void *vret)
{
unsigned char *ret;
unsigned long byte,byte_bit;
unsigned long i;
unsigned char uchar;
/* The table is checked when it is built to ensure all
values are valid. */
ret = vret;
byte=bit/8; /* find the byte where the data starts */
byte_bit=bit%8; /* find the bit in the byte where the data starts */
if(length<9) { /* one byte or less */
uchar = cmos_read(byte); /* load the byte */
uchar >>= byte_bit; /* shift the bits to byte align */
/* clear unspecified bits */
ret[0] = uchar & ((1 << length) -1);
}
else { /* more that one byte so transfer the whole bytes */
for(i=0;length;i++,length-=8,byte++) {
/* load the byte */
ret[i]=cmos_read(byte);
}
}
return 0;
}
int get_option(void *dest, const char *name)
{
extern struct cmos_option_table option_table;
struct cmos_option_table *ct;
struct cmos_entries *ce;
size_t namelen;
int found=0;
/* Figure out how long name is */
namelen = strnlen(name, CMOS_MAX_NAME_LENGTH);
/* find the requested entry record */
ct=&option_table;
ce=(struct cmos_entries*)((unsigned char *)ct + ct->header_length);
for(;ce->tag==LB_TAG_OPTION;
ce=(struct cmos_entries*)((unsigned char *)ce + ce->size)) {
if (memcmp(ce->name, name, namelen) == 0) {
found=1;
break;
}
}
if(!found) {
printk(BIOS_DEBUG, "WARNING: No CMOS option '%s'.\n", name);
return(-2);
}
if(get_cmos_value(ce->bit, ce->length, dest))
return(-3);
if(!rtc_checksum_valid(LB_CKS_RANGE_START,
LB_CKS_RANGE_END,LB_CKS_LOC))
return(-4);
return(0);
}
#endif /* CONFIG_USE_OPTION_TABLE */
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