1 files changed, 249 insertions, 0 deletions
diff --git a/src/pc80/mc146818rtc.c b/src/pc80/mc146818rtc.c
new file mode 100644
index 0000000000..b77653c52e
--- /dev/null
+++ b/src/pc80/mc146818rtc.c
@@ -0,0 +1,249 @@
+#include <console/console.h>
+#include <arch/io.h>
+#include <pc80/mc146818rtc.h>
+#include <boot/linuxbios_tables.h>
+#include <string.h>
+
+#define CMOS_READ(addr) ({ \
+outb((addr),RTC_PORT(0)); \
+inb(RTC_PORT(1)); \
+})
+
+#define CMOS_WRITE(val, addr) ({ \
+outb((addr),RTC_PORT(0)); \
+outb((val),RTC_PORT(1)); \
+})
+
+/* 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 */
+/**********************************************************************/
+
+
+
+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);
+}
+
+#define RTC_CONTROL_DEFAULT (RTC_24H)
+#define RTC_FREQ_SELECT_DEFAULT (RTC_REF_CLCK_32KHZ | RTC_RATE_1024HZ)
+
+#if 0 /* alpha setup */
+#undef RTC_CONTROL_DEFAULT
+#undef RTC_FREQ_SELECT_DEFAULT
+#define RTC_CONTROL_DEFAULT (RTC_SQWE | RTC_24H)
+#define RTC_FREQ_SELECT_DEFAULT (RTC_REF_CLCK_32KHZ | RTC_RATE_1024HZ)
+#endif
+void rtc_init(int invalid)
+{
+	unsigned char x;
+	int cmos_invalid, checksum_invalid;
+
+  printk_debug("RTC Init\n");
+	/* 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) {
+		int i;
+		printk_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
+	}
+	/* 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_debug("Invalid CMOS LB checksum\n");
+
+	/* 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);
+	/* Make certain we have a valid checksum */
+	rtc_set_checksum(PC_CKS_RANGE_START,
+                        PC_CKS_RANGE_END,PC_CKS_LOC);
+	/* Clear any pending interrupts */
+	(void) CMOS_READ(RTC_INTR_FLAGS);
+}
+
+
+#if USE_OPTION_TABLE == 1
+/* 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, 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_err("ERROR: 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 /* USE_OPTION_TABLE */