hwclock: remove alpha cmos

Remove alpha direct I/O access, use RTC instead:
http://marc.info/?l=util-linux-ng&m=141682406902804

Resolves the alpha 2020 issue for util-linux:
http://marc.info/?l=util-linux-ng&m=148387021519787

Now it is only the kernel's RTC problem.

* sys-utils/hwclock.c: remove alpha cmos
* sys-utils/hwclock-cmos.c: same
* sys-utils/hwclock.h: same
* sys-utils/hwclock.8.in: same

Signed-off-by: J William Piggott <elseifthen@gmx.com>

1 files changed, 39 insertions, 277 deletions

diff --git a/sys-utils/hwclock-cmos.c b/sys-utils/hwclock-cmos.c
index 4915471bd..7a9d595b3 100644
--- a/sys-utils/hwclock-cmos.c
+++ b/sys-utils/hwclock-cmos.c
@@ -76,17 +76,8 @@ static int inb(int c __attribute__((__unused__)))
 	return 0;
 }
 # endif				/* __i386__ __x86_64__ */
-#elif defined(__alpha__)
-# ifdef HAVE_SYS_IO_H
-#  include <sys/io.h>
-# else
-/* <asm/io.h> fails to compile, probably because of u8 etc */
-extern unsigned int inb(unsigned long port);
-extern void outb(unsigned char b, unsigned long port);
-extern int iopl(int level);
-# endif
-#else				/* __alpha__ */
-# warning "disable cmos access - not i386, x86_64, or alpha"
+#else
+# warning "disable cmos access - not i386 or x86_64"
 static void outb(int a __attribute__((__unused__)),
 		 int b __attribute__((__unused__)))
 {
@@ -106,201 +97,18 @@ static int inb(int c __attribute__((__unused__)))
 #define IOPL_NOT_IMPLEMENTED -2
 
 /*
- * The epoch.
- *
- * Unix uses 1900 as epoch for a struct tm, and 1970 for a time_t. But what
- * was written to CMOS?
- *
- * Digital DECstations use 1928 - this is on a mips or alpha Digital Unix
- * uses 1952, e.g. on AXPpxi33. Windows NT uses 1980. The ARC console
- * expects to boot Windows NT and uses 1980. (But a Ruffian uses 1900, just
- * like SRM.) It is reported that ALPHA_PRE_V1_2_SRM_CONSOLE uses 1958.
+ * POSIX uses 1900 as epoch for a struct tm, and 1970 for a time_t.
  */
 #define TM_EPOCH 1900
-static int cmos_epoch = 1900;
 
-/*
- * Martin Ostermann writes:
- *
- * The problem with the Jensen is twofold: First, it has the clock at a
- * different address. Secondly, it has a distinction between "local" and
- * normal bus addresses. The local ones pertain to the hardware integrated
- * into the chipset, like serial/parallel ports and of course, the RTC.
- * Those need to be addressed differently. This is handled fine in the
- * kernel, and it's not a problem, since this usually gets totally optimized
- * by the compile. But the i/o routines of (g)libc lack this support so far.
- * The result of this is, that the old clock program worked only on the
- * Jensen when USE_DEV_PORT was defined, but not with the normal inb/outb
- * functions.
- */
-static int use_dev_port = 0;		/* 1 for Jensen */
-static int dev_port_fd;
-static unsigned short clock_ctl_addr = 0x70;	/* 0x170 for Jensen */
-static unsigned short clock_data_addr = 0x71;	/* 0x171 for Jensen */
+static unsigned short clock_ctl_addr = 0x70;
+static unsigned short clock_data_addr = 0x71;
 
 static int century_byte = 0;		/* 0: don't access a century byte
 					 * 50 (0x32): usual PC value
 					 * 55 (0x37): PS/2
 					 */
 
-#ifdef __alpha__
-static int funkyTOY = 0;		/* 1 for PC164/LX164/SX164 type alpha */
-#endif
-
-#ifdef __alpha
-
-static int is_in_cpuinfo(char *fmt, char *str)
-{
-	FILE *cpuinfo;
-	char field[256];
-	char format[sizeof(field)];
-	int found = 0;
-
-	sprintf(format, "%s : %s", fmt, "%255s");
-
-	cpuinfo = fopen(_PATH_PROC_CPUINFO, "r");
-	if (cpuinfo) {
-		do {
-			if (fscanf(cpuinfo, format, field) == 1) {
-				if (strncmp(field, str, strlen(str)) == 0)
-					found = 1;
-				break;
-			}
-		} while (fgets(field, 256, cpuinfo));
-		fclose(cpuinfo);
-	}
-	return found;
-}
-
-/*
- * Set cmos_epoch, either from user options, or by asking the kernel, or by
- * looking at /proc/cpu_info
- */
-void set_cmos_epoch(const struct hwclock_control *ctl)
-{
-	unsigned long epoch;
-
-	/* Believe the user */
-	if (ctl->epoch_option) {
-		cmos_epoch = ctl->epoch_option;
-		return;
-	}
-
-	if (ctl->ARCconsole)
-		cmos_epoch = 1980;
-
-	if (ctl->ARCconsole || ctl->SRM)
-		return;
-
-#ifdef __linux__
-	/*
-	 * If we can ask the kernel, we don't need guessing from
-	 * /proc/cpuinfo
-	 */
-	if (get_epoch_rtc(ctl, &epoch, 1) == 0) {
-		cmos_epoch = epoch;
-		return;
-	}
-#endif
-
-	/*
-	 * The kernel source today says: read the year.
-	 *
-	 * If it is in  0-19 then the epoch is 2000.
-	 * If it is in 20-47 then the epoch is 1980.
-	 * If it is in 48-69 then the epoch is 1952.
-	 * If it is in 70-99 then the epoch is 1928.
-	 *
-	 * Otherwise the epoch is 1900.
-	 * TODO: Clearly, this must be changed before 2019.
-	 */
-	/*
-	 * See whether we are dealing with SRM or MILO, as they have
-	 * different "epoch" ideas.
-	 */
-	if (is_in_cpuinfo("system serial number", "MILO")) {
-		if (ctl->debug)
-			printf(_("booted from MILO\n"));
-		/*
-		 * See whether we are dealing with a RUFFIAN aka Alpha PC-164
-		 * UX (or BX), as they have REALLY different TOY (TimeOfYear)
-		 * format: BCD, and not an ARC-style epoch.  BCD is detected
-		 * dynamically, but we must NOT adjust like ARC.
-		 */
-		if (is_in_cpuinfo("system type", "Ruffian")) {
-			if (debug)
-				printf(_("Ruffian BCD clock\n"));
-			return;
-		}
-	}
-
-	cmos_epoch = 1980;
-}
-
-void set_cmos_access(const struct hwclock_control *ctl)
-{
-
-	/*
-	 * See whether we're dealing with a Jensen---it has a weird I/O
-	 * system. DEC was just learning how to build Alpha PCs.
-	 */
-	if (ctl->Jensen || is_in_cpuinfo("system type", "Jensen")) {
-		use_dev_port = 1;
-		clock_ctl_addr = 0x170;
-		clock_data_addr = 0x171;
-		if (ctl->debug)
-			printf(_("clockport adjusted to 0x%x\n"),
-			       clock_ctl_addr);
-	}
-
-	/*
-	 * See whether we are dealing with PC164/LX164/SX164, as they have a
-	 * TOY that must be accessed differently to work correctly.
-	 */
-	/* Nautilus stuff reported by Neoklis Kyriazis */
-	if (ctl->funky_toy ||
-	    is_in_cpuinfo("system variation", "PC164") ||
-	    is_in_cpuinfo("system variation", "LX164") ||
-	    is_in_cpuinfo("system variation", "SX164") ||
-	    is_in_cpuinfo("system type", "Nautilus")) {
-		funkyTOY = 1;
-		if (ctl->debug)
-			printf(_("funky TOY!\n"));
-	}
-}
-#endif				/* __alpha */
-
-#ifdef __alpha__
-/*
- * The Alpha doesn't allow user-level code to disable interrupts (for good
- * reasons). Instead, we ensure atomic operation by performing the operation
- * and checking whether the high 32 bits of the cycle counter changed. If
- * they did, a context switch must have occurred and we redo the operation.
- * As long as the operation is reasonably short, it will complete
- * atomically, eventually.
- */
-static unsigned long
-atomic(const char *name,
-       unsigned long (*op) (const struct hwclock_control *ctl, unsigned long),
-       const struct hwclock_control *ctl,
-       unsigned long arg)
-{
-	unsigned long ts1, ts2, n, v;
-
-	for (n = 0; n < 1000; ++n) {
-		asm volatile ("rpcc %0":"r=" (ts1));
-		v = (*op) (ctl, arg);
-		asm volatile ("rpcc %0":"r=" (ts2));
-
-		if ((ts1 ^ ts2) >> 32 == 0) {
-			return v;
-		}
-	}
-	errx(EXIT_FAILURE, _("atomic %s failed for 1000 iterations!"),
-		name);
-}
-#else
-
 /*
  * Hmmh, this isn't very atomic. Maybe we should force an error instead?
  *
@@ -315,68 +123,37 @@ atomic(const char *name __attribute__ ((__unused__)),
 	return (*op) (ctl, arg);
 }
 
-#endif
+/*
+ * We only want to read CMOS data, but unfortunately writing to bit 7
+ * disables (1) or enables (0) NMI; since this bit is read-only we have
+ * to guess the old status. Various docs suggest that one should disable
+ * NMI while reading/writing CMOS data, and enable it again afterwards.
+ * This would yield the sequence
+ *
+ *  outb (reg | 0x80, 0x70);
+ *  val = inb(0x71);
+ *  outb (0x0d, 0x70);  // 0x0d: random read-only location
+ *
+ * Other docs state that "any write to 0x70 should be followed by an
+ * action to 0x71 or the RTC will be left in an unknown state". Most
+ * docs say that it doesn't matter at all what one does.
+ *
+ * bit 0x80: disable NMI while reading - should we? Let us follow the
+ * kernel and not disable. Called only with 0 <= reg < 128
+ */
 
 static inline unsigned long cmos_read(const struct hwclock_control *ctl,
 				      unsigned long reg)
 {
-	if (use_dev_port) {
-		unsigned char v = reg | 0x80;
-		lseek(dev_port_fd, clock_ctl_addr, 0);
-		if (write(dev_port_fd, &v, 1) == -1 && ctl->debug)
-			warn(_("cmos_read(): write to control address %X failed"),
-			       clock_ctl_addr);
-		lseek(dev_port_fd, clock_data_addr, 0);
-		if (read(dev_port_fd, &v, 1) == -1 && ctl->debug)
-			warn(_("cmos_read(): read from data address %X failed"),
-			       clock_data_addr);
-		return v;
-	} else {
-		/*
-		 * We only want to read CMOS data, but unfortunately writing
-		 * to bit 7 disables (1) or enables (0) NMI; since this bit
-		 * is read-only we have to guess the old status. Various
-		 * docs suggest that one should disable NMI while
-		 * reading/writing CMOS data, and enable it again
-		 * afterwards. This would yield the sequence
-		 *
-		 *  outb (reg | 0x80, 0x70);
-		 *  val = inb(0x71);
-		 *  outb (0x0d, 0x70);  // 0x0d: random read-only location
-		 *
-		 * Other docs state that "any write to 0x70 should be
-		 * followed by an action to 0x71 or the RTC will be left in
-		 * an unknown state". Most docs say that it doesn't matter at
-		 * all what one does.
-		 */
-		/*
-		 * bit 0x80: disable NMI while reading - should we? Let us
-		 * follow the kernel and not disable. Called only with 0 <=
-		 * reg < 128
-		 */
-		outb(reg, clock_ctl_addr);
-		return inb(clock_data_addr);
-	}
+	outb(reg, clock_ctl_addr);
+	return inb(clock_data_addr);
 }
 
 static inline unsigned long cmos_write(const struct hwclock_control *ctl,
 				       unsigned long reg, unsigned long val)
 {
-	if (use_dev_port) {
-		unsigned char v = reg | 0x80;
-		lseek(dev_port_fd, clock_ctl_addr, 0);
-		if (write(dev_port_fd, &v, 1) == -1 && ctl->debug)
-			warn(_("cmos_write(): write to control address %X failed"),
-			       clock_ctl_addr);
-		v = (val & 0xff);
-		lseek(dev_port_fd, clock_data_addr, 0);
-		if (write(dev_port_fd, &v, 1) == -1 && ctl->debug)
-			warn(_("cmos_write(): write to data address %X failed"),
-			       clock_data_addr);
-	} else {
-		outb(reg, clock_ctl_addr);
-		outb(val, clock_data_addr);
-	}
+	outb(reg, clock_ctl_addr);
+	outb(val, clock_data_addr);
 	return 0;
 }
 
@@ -409,9 +186,7 @@ static unsigned long cmos_set_time(const struct hwclock_control *ctl,
 	save_freq_select = cmos_read(ctl, 10);	/* stop and reset prescaler */
 	cmos_write(ctl, 10, (save_freq_select | 0x70));
 
-	tm.tm_year += TM_EPOCH;
-	century = tm.tm_year / 100;
-	tm.tm_year -= cmos_epoch;
+	century = (tm.tm_year + TM_EPOCH) / 100;
 	tm.tm_year %= 100;
 	tm.tm_mon += 1;
 	tm.tm_wday += 1;
@@ -475,10 +250,6 @@ static void hclock_set_time(const struct hwclock_control *ctl, const struct tm *
 static inline int cmos_clock_busy(const struct hwclock_control *ctl)
 {
 	return
-#ifdef __alpha__
-	    /* poll bit 4 (UF) of Control Register C */
-	    funkyTOY ? (hclock_read(ctl, 12) & 0x10) :
-#endif
 	    /* poll bit 7 (UIP) of Control Register A */
 	    (hclock_read(ctl, 10) & 0x80);
 }
@@ -594,7 +365,6 @@ static int read_hardware_clock_cmos(const struct hwclock_control *ctl
 	 */
 	tm->tm_wday -= 1;
 	tm->tm_mon -= 1;
-	tm->tm_year += (cmos_epoch - TM_EPOCH);
 	if (tm->tm_year < 69)
 		tm->tm_year += 100;
 	if (pmbit) {
@@ -616,7 +386,7 @@ static int set_hardware_clock_cmos(const struct hwclock_control *ctl
 	return 0;
 }
 
-#if defined(__i386__) || defined(__alpha__) || defined(__x86_64__)
+#if defined(__i386__) || defined(__x86_64__)
 # if defined(HAVE_IOPL)
 static int i386_iopl(const int level)
 {
@@ -640,23 +410,15 @@ static int get_permissions_cmos(void)
 {
 	int rc;
 
-	if (use_dev_port) {
-		if ((dev_port_fd = open(_PATH_DEV_PORT, O_RDWR)) < 0) {
-			warn(_("cannot open %s"), _PATH_DEV_PORT);
-			rc = 1;
-		} else
-			rc = 0;
-	} else {
-		rc = i386_iopl(3);
-		if (rc == IOPL_NOT_IMPLEMENTED) {
-			warnx(_("I failed to get permission because I didn't try."));
-		} else if (rc != 0) {
-			rc = errno;
-			warn(_("unable to get I/O port access:  "
-			       "the iopl(3) call failed"));
-			if (rc == EPERM && geteuid())
-				warnx(_("Probably you need root privileges.\n"));
-		}
+	rc = i386_iopl(3);
+	if (rc == IOPL_NOT_IMPLEMENTED) {
+		warnx(_("I failed to get permission because I didn't try."));
+	} else if (rc != 0) {
+		rc = errno;
+		warn(_("unable to get I/O port access:  "
+		       "the iopl(3) call failed"));
+		if (rc == EPERM && geteuid())
+			warnx(_("Probably you need root privileges.\n"));
 	}
 	return rc ? 1 : 0;
 }
@@ -676,7 +438,7 @@ static struct clock_ops cmos_interface = {
 struct clock_ops *probe_for_cmos_clock(void)
 {
 	static const int have_cmos =
-#if defined(__i386__) || defined(__alpha__) || defined(__x86_64__)
+#if defined(__i386__) || defined(__x86_64__)
 	    TRUE;
 #else
 	    FALSE;