[Qemu-devel] [PATCH 8/16] S3C Real Time Clock

[Vincent Sanders <vince@kyllikki.org>]

Real Time clock

Signed-off-by: Vincent Sanders <vince@simtec.co.uk>
---
 s3c24xx_rtc.c |  123 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 123 insertions(+)

diff -urN qemusvnclean/hw/s3c24xx_rtc.c qemusvnpatches/hw/s3c24xx_rtc.c
--- qemusvnclean/hw/s3c24xx_rtc.c	1970-01-01 01:00:00.000000000 +0100
+++ qemusvnpatches/hw/s3c24xx_rtc.c	2009-04-23 17:07:07.000000000 +0100
@@ -0,0 +1,123 @@
+/* hw/s3c24xx_rtc.c
+ *
+ * Samsung S3C24XX RTC emulation
+ *
+ * Copyright 2006, 2007, 2008 Daniel Silverstone and Vincent Sanders
+ *
+ * This file is under the terms of the GNU General Public
+ * License Version 2
+ */
+
+#include "hw.h"
+
+#include "s3c24xx.h"
+
+
+/* RTC Control RW Byte */
+#define S3C_REG_RTCCON 0
+/* Tick time count RW Byte */
+#define S3C_REG_TICNT 1
+/* RTC Alarm Control RW Byte */
+#define S3C_REG_RTCALM 4
+/* Alarm second */
+#define S3C_REG_ALMSEC 5
+/* Alarm minute */
+#define S3C_REG_ALMMIN 6
+/* Alarm hour */
+#define S3C_REG_ALMHOUR 7
+/* Alarm day */
+#define S3C_REG_ALMDATE 8
+/* Alarm month */
+#define S3C_REG_ALMMON 9
+/* Alarm year */
+#define S3C_REG_ALMYEAR 10
+/* RTC Round Reset */
+#define S3C_REG_RTCRST 11
+/* BCD Second */
+#define S3C_REG_BCDSEC 12
+/* BCD Minute */
+#define S3C_REG_BCDMIN 13
+/* BCD Hour */
+#define S3C_REG_BCDHOUR 14
+/* BCD Day */
+#define S3C_REG_BCDDATE 15
+/* BCD Day of week */
+#define S3C_REG_BCDDAY 16
+/* BCD Month */
+#define S3C_REG_BCDMON 17
+/* BCD Year */
+#define S3C_REG_BCDYEAR 18
+
+static inline int to_bcd(int a)
+{
+    return ((a/10)<<4) | (a%10);
+}
+
+static void update_time(S3CState *soc)
+{
+    time_t ti;
+    struct tm *tm;
+    /* update the RTC registers from system time */
+    time(&ti);
+    tm = gmtime(&ti);
+    soc->rtc_reg[S3C_REG_BCDSEC] = to_bcd(tm->tm_sec);
+    soc->rtc_reg[S3C_REG_BCDMIN] = to_bcd(tm->tm_min);
+    soc->rtc_reg[S3C_REG_BCDHOUR] = to_bcd(tm->tm_hour);
+    soc->rtc_reg[S3C_REG_BCDDATE] = to_bcd(tm->tm_mday);
+    soc->rtc_reg[S3C_REG_BCDDAY] = to_bcd(tm->tm_wday + 1);
+    soc->rtc_reg[S3C_REG_BCDMON] = to_bcd(tm->tm_mon + 1);
+    soc->rtc_reg[S3C_REG_BCDYEAR] =  to_bcd(tm->tm_year - 100);
+}
+
+static void
+s3c24xx_rtc_write_f(void *opaque, target_phys_addr_t addr_, uint32_t value)
+{
+    S3CState *soc = (S3CState *)opaque;
+    int addr = (addr_ - 0x40) >> 2;
+    if (addr < 0 || addr > 18) 
+        addr = 18;
+
+    soc->rtc_reg[addr] = value;
+}
+
+static uint32_t
+s3c24xx_rtc_read_f(void *opaque, target_phys_addr_t addr_)
+{
+    S3CState *soc = (S3CState *)opaque;
+    int addr = (addr_ - 0x40) >> 2;
+
+    if (addr < 0 || addr > 18) 
+        addr = 18;
+
+    update_time(soc);        
+
+    return soc->rtc_reg[addr];
+}
+
+static CPUReadMemoryFunc *s3c24xx_rtc_read[] = {
+    &s3c24xx_rtc_read_f,
+    &s3c24xx_rtc_read_f,
+    &s3c24xx_rtc_read_f,
+};
+
+static CPUWriteMemoryFunc *s3c24xx_rtc_write[] = {
+    &s3c24xx_rtc_write_f,
+    &s3c24xx_rtc_write_f,
+    &s3c24xx_rtc_write_f,
+};
+
+
+void
+s3c24xx_rtc_init(S3CState *soc, target_phys_addr_t base_addr)
+{
+    int tag;
+    tag = cpu_register_io_memory(0, s3c24xx_rtc_read, s3c24xx_rtc_write, soc);
+
+    /* there are only 19 real registers but they start at offset 0x40 into the
+     * range so we have 35 registers mapped 
+     */
+    cpu_register_physical_memory(base_addr, 35 * 4, tag);
+
+    /* set the RTC so it appears active */
+    soc->rtc_reg[S3C_REG_RTCCON] = 1;
+}

-- 
Regards Vincent
http://www.kyllikki.org/