Pull up following revision(s) (requested by hgutch in ticket #54):

	sys/arch/evbppc/wii/dev/rtcsram.c: revision 1.4
	sys/arch/evbppc/wii/dev/rtcsram.c: revision 1.5

Wii: size of ead is 4 bytes each

wii: rtcsram: Ignore counter bias when reading/writing RTC.

Counter bias is used by system menu as an offset from the RTC for the
time displayed in the Wii's OS. Since Wii doesn't have a concept of time
zones, this bias is useless to us.

Due to a previous bug with parsing SRAM data, the bias read was always 0.

Now that the bias is read correctly, we're reading and writing
preposterous times -- remove the bias from the calculation to restore
the previous setting.

So with this change, the RTC is always in UTC and the Wii system menu
date/time settings adjusts the bias as an offset from that.

Author: MartinHusemann

sys/arch/evbppc/wii/dev/rtcsram.c

@@ -1,4 +1,4 @@
-/* $NetBSD: rtcsram.c,v 1.2 2024/02/10 11:00:15 jmcneill Exp $ */
+/* $NetBSD: rtcsram.c,v 1.2.4.1 2025/10/17 08:35:27 martin Exp $ */
 
 /*-
  * Copyright (c) 2024 Jared McNeill <jmcneill@invisible.ca>
@@ -27,7 +27,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: rtcsram.c,v 1.2 2024/02/10 11:00:15 jmcneill Exp $");
+__KERNEL_RCSID(0, "$NetBSD: rtcsram.c,v 1.2.4.1 2025/10/17 08:35:27 martin Exp $");
 
 #include <sys/param.h>
 #include <sys/bus.h>
@@ -49,7 +49,7 @@ __KERNEL_RCSID(0, "$NetBSD: rtcsram.c,v 1.2 2024/02/10 11:00:15 jmcneill Exp $")
 
 struct rtcsram_sram {
 	uint16_t	checksum[2];
-	uint16_t	ead[2];
+	uint32_t	ead[2];
 	int32_t		counter_bias;
 	int8_t		display_offset_h;
 	uint8_t		ntd;
@@ -108,9 +108,7 @@ rtcsram_attach(device_t parent, device_t self, void *aux)
 	sc->sc_chan = eaa->eaa_chan;
 	sc->sc_device = eaa->eaa_device;
 
-	/* Read RTC counter bias from SRAM. */
 	rtcsram_read_buf(sc, SRAM_BASE, &sc->sc_sram, sizeof(sc->sc_sram));
-	aprint_debug_dev(self, "counter bias %d\n", sc->sc_sram.counter_bias);
 	hexdump(aprint_debug, device_xname(self), &sc->sc_sram,
 	    sizeof(sc->sc_sram));
 
@@ -161,7 +159,7 @@ rtcsram_gettime(todr_chip_handle_t ch, struct timeval *tv)
 	uint32_t val;
 
 	val = rtcsram_read_4(sc, RTC_BASE);
-	tv->tv_sec = (uint64_t)val + sc->sc_sram.counter_bias;
+	tv->tv_sec = (uint64_t)val;
 	tv->tv_usec = 0;
 
 	return 0;
@@ -172,7 +170,7 @@ rtcsram_settime(todr_chip_handle_t ch, struct timeval *tv)
 {
 	struct rtcsram_softc * const sc = ch->cookie;
 
-	rtcsram_write_4(sc, RTC_BASE, tv->tv_sec - sc->sc_sram.counter_bias);
+	rtcsram_write_4(sc, RTC_BASE, tv->tv_sec);
 
 	return 0;
 }