On Fri, 8 Jun 2018, Cédric Le Goater wrote:
On 06/06/2018 03:31 PM, BALATON Zoltan wrote:
Basic emulation of the M41T80 serial (I2C) RTC chip. Only getting time
of day is implemented. Setting time and RTC alarm are not supported.
Signed-off-by: BALATON Zoltan <bala...@eik.bme.hu>
---
MAINTAINERS | 1 +
default-configs/ppc-softmmu.mak | 1 +
hw/timer/Makefile.objs | 1 +
hw/timer/m41t80.c | 117 ++++++++++++++++++++++++++++++++++++++++
4 files changed, 120 insertions(+)
create mode 100644 hw/timer/m41t80.c
diff --git a/MAINTAINERS b/MAINTAINERS
index 41cd373..9e13bc1 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -826,6 +826,7 @@ M: BALATON Zoltan <bala...@eik.bme.hu>
L: qemu-...@nongnu.org
S: Maintained
F: hw/ide/sii3112.c
+F: hw/timer/m41t80.c
SH4 Machines
------------
diff --git a/default-configs/ppc-softmmu.mak b/default-configs/ppc-softmmu.mak
index 7d0dc2f..9fbaadc 100644
--- a/default-configs/ppc-softmmu.mak
+++ b/default-configs/ppc-softmmu.mak
@@ -27,6 +27,7 @@ CONFIG_SM501=y
CONFIG_IDE_SII3112=y
CONFIG_I2C=y
CONFIG_BITBANG_I2C=y
+CONFIG_M41T80=y
# For Macs
CONFIG_MAC=y
diff --git a/hw/timer/Makefile.objs b/hw/timer/Makefile.objs
index 8b27a4b..e16b2b9 100644
--- a/hw/timer/Makefile.objs
+++ b/hw/timer/Makefile.objs
@@ -6,6 +6,7 @@ common-obj-$(CONFIG_CADENCE) += cadence_ttc.o
common-obj-$(CONFIG_DS1338) += ds1338.o
common-obj-$(CONFIG_HPET) += hpet.o
common-obj-$(CONFIG_I8254) += i8254_common.o i8254.o
+common-obj-$(CONFIG_M41T80) += m41t80.o
common-obj-$(CONFIG_M48T59) += m48t59.o
ifeq ($(CONFIG_ISA_BUS),y)
common-obj-$(CONFIG_M48T59) += m48t59-isa.o
diff --git a/hw/timer/m41t80.c b/hw/timer/m41t80.c
new file mode 100644
index 0000000..9dbdb1b
--- /dev/null
+++ b/hw/timer/m41t80.c
@@ -0,0 +1,117 @@
+/*
+ * M41T80 serial rtc emulation
+ *
+ * Copyright (c) 2018 BALATON Zoltan
+ *
+ * This work is licensed under the GNU GPL license version 2 or later.
+ *
+ */
+
+#include "qemu/osdep.h"
+#include "qemu/log.h"
+#include "qemu/timer.h"
+#include "qemu/bcd.h"
+#include "hw/i2c/i2c.h"
+
+#define TYPE_M41T80 "m41t80"
+#define M41T80(obj) OBJECT_CHECK(M41t80State, (obj), TYPE_M41T80)
+
+typedef struct M41t80State {
+ I2CSlave parent_obj;
+ int8_t addr;
+} M41t80State;
+
+static void m41t80_realize(DeviceState *dev, Error **errp)
+{
+ M41t80State *s = M41T80(dev);
+
+ s->addr = -1;
+}
+
+static int m41t80_send(I2CSlave *i2c, uint8_t data)
+{
+ M41t80State *s = M41T80(i2c);
+
+ if (s->addr < 0) {
+ s->addr = data;
+ } else {
+ s->addr++;
+ }
+ return 0;
+}
+
+static int m41t80_recv(I2CSlave *i2c)
+{
+ M41t80State *s = M41T80(i2c);
+ struct tm now;
+ qemu_timeval tv;
+
+ if (s->addr < 0) {
+ s->addr = 0;
+ }
+ if (s->addr >= 1 && s->addr <= 7) {
+ qemu_get_timedate(&now, -1);
+ }
+ switch (s->addr++) {
you could use some define to name the registers :
This was also suggested by Philippe Mathieu-Daudé and my answer to that
was that I don't feel like I want to come up with names the datasheet does
not have either. I think this device is simple enough with just 20
consecutively numbered registers that appear only in these switch cases by
number as in the datasheet table so that I don't want to make it more
difficult to read by encrypting these numbers behind some arbitrary
defines without a good reason. They are also so simple that it's clear
from the usually one line implementation what they do so that's also not a
good reason to name them.
+ case 0:
+ qemu_gettimeofday(&tv);
+ return to_bcd(tv.tv_usec / 10000);> + case 1:
+ return to_bcd(now.tm_sec);
+ case 2:
+ return to_bcd(now.tm_min);
+ case 3:
+ return to_bcd(now.tm_hour);
There is an interesting century bit in specs.
Which I could not figure out how should work and guests seem to be happy
without it so I did not try to implement it.
+ case 4:
+ return to_bcd(now.tm_wday);
+ case 5:
+ return to_bcd(now.tm_mday);
+ case 6:
+ return to_bcd(now.tm_mon + 1);
+ case 7:
+ return to_bcd(now.tm_year % 100);
+ case 8 ... 19:
+ qemu_log_mask(LOG_UNIMP, "\n%s: unimplemented register: %d\n",
is the beginning \n needed ?
Probably not, maybe left there due to previous debug logs I've removed.
I'll drop the beginning \n-s in next version.
Thanks,
C.
Thanks for the review,
BALATON Zoltan
