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-rw-r--r--hw/timer/aspeed_rtc.c180
1 files changed, 180 insertions, 0 deletions
diff --git a/hw/timer/aspeed_rtc.c b/hw/timer/aspeed_rtc.c
new file mode 100644
index 0000000000..19f061c846
--- /dev/null
+++ b/hw/timer/aspeed_rtc.c
@@ -0,0 +1,180 @@
+/*
+ * ASPEED Real Time Clock
+ * Joel Stanley <joel@jms.id.au>
+ *
+ * Copyright 2019 IBM Corp
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+#include "qemu/osdep.h"
+#include "qemu-common.h"
+#include "hw/timer/aspeed_rtc.h"
+#include "qemu/log.h"
+#include "qemu/timer.h"
+
+#include "trace.h"
+
+#define COUNTER1 (0x00 / 4)
+#define COUNTER2 (0x04 / 4)
+#define ALARM (0x08 / 4)
+#define CONTROL (0x10 / 4)
+#define ALARM_STATUS (0x14 / 4)
+
+#define RTC_UNLOCKED BIT(1)
+#define RTC_ENABLED BIT(0)
+
+static void aspeed_rtc_calc_offset(AspeedRtcState *rtc)
+{
+ struct tm tm;
+ uint32_t year, cent;
+ uint32_t reg1 = rtc->reg[COUNTER1];
+ uint32_t reg2 = rtc->reg[COUNTER2];
+
+ tm.tm_mday = (reg1 >> 24) & 0x1f;
+ tm.tm_hour = (reg1 >> 16) & 0x1f;
+ tm.tm_min = (reg1 >> 8) & 0x3f;
+ tm.tm_sec = (reg1 >> 0) & 0x3f;
+
+ cent = (reg2 >> 16) & 0x1f;
+ year = (reg2 >> 8) & 0x7f;
+ tm.tm_mon = ((reg2 >> 0) & 0x0f) - 1;
+ tm.tm_year = year + (cent * 100) - 1900;
+
+ rtc->offset = qemu_timedate_diff(&tm);
+}
+
+static uint32_t aspeed_rtc_get_counter(AspeedRtcState *rtc, int r)
+{
+ uint32_t year, cent;
+ struct tm now;
+
+ qemu_get_timedate(&now, rtc->offset);
+
+ switch (r) {
+ case COUNTER1:
+ return (now.tm_mday << 24) | (now.tm_hour << 16) |
+ (now.tm_min << 8) | now.tm_sec;
+ case COUNTER2:
+ cent = (now.tm_year + 1900) / 100;
+ year = now.tm_year % 100;
+ return ((cent & 0x1f) << 16) | ((year & 0x7f) << 8) |
+ ((now.tm_mon + 1) & 0xf);
+ default:
+ g_assert_not_reached();
+ }
+}
+
+static uint64_t aspeed_rtc_read(void *opaque, hwaddr addr,
+ unsigned size)
+{
+ AspeedRtcState *rtc = opaque;
+ uint64_t val;
+ uint32_t r = addr >> 2;
+
+ switch (r) {
+ case COUNTER1:
+ case COUNTER2:
+ if (rtc->reg[CONTROL] & RTC_ENABLED) {
+ rtc->reg[r] = aspeed_rtc_get_counter(rtc, r);
+ }
+ /* fall through */
+ case CONTROL:
+ val = rtc->reg[r];
+ break;
+ case ALARM:
+ case ALARM_STATUS:
+ default:
+ qemu_log_mask(LOG_UNIMP, "%s: 0x%" HWADDR_PRIx "\n", __func__, addr);
+ return 0;
+ }
+
+ trace_aspeed_rtc_read(addr, val);
+
+ return val;
+}
+
+static void aspeed_rtc_write(void *opaque, hwaddr addr,
+ uint64_t val, unsigned size)
+{
+ AspeedRtcState *rtc = opaque;
+ uint32_t r = addr >> 2;
+
+ switch (r) {
+ case COUNTER1:
+ case COUNTER2:
+ if (!(rtc->reg[CONTROL] & RTC_UNLOCKED)) {
+ break;
+ }
+ /* fall through */
+ case CONTROL:
+ rtc->reg[r] = val;
+ aspeed_rtc_calc_offset(rtc);
+ break;
+ case ALARM:
+ case ALARM_STATUS:
+ default:
+ qemu_log_mask(LOG_UNIMP, "%s: 0x%" HWADDR_PRIx "\n", __func__, addr);
+ break;
+ }
+ trace_aspeed_rtc_write(addr, val);
+}
+
+static void aspeed_rtc_reset(DeviceState *d)
+{
+ AspeedRtcState *rtc = ASPEED_RTC(d);
+
+ rtc->offset = 0;
+ memset(rtc->reg, 0, sizeof(rtc->reg));
+}
+
+static const MemoryRegionOps aspeed_rtc_ops = {
+ .read = aspeed_rtc_read,
+ .write = aspeed_rtc_write,
+ .endianness = DEVICE_NATIVE_ENDIAN,
+};
+
+static const VMStateDescription vmstate_aspeed_rtc = {
+ .name = TYPE_ASPEED_RTC,
+ .version_id = 1,
+ .fields = (VMStateField[]) {
+ VMSTATE_UINT32_ARRAY(reg, AspeedRtcState, 0x18),
+ VMSTATE_INT32(offset, AspeedRtcState),
+ VMSTATE_INT32(offset, AspeedRtcState),
+ VMSTATE_END_OF_LIST()
+ }
+};
+
+static void aspeed_rtc_realize(DeviceState *dev, Error **errp)
+{
+ SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
+ AspeedRtcState *s = ASPEED_RTC(dev);
+
+ sysbus_init_irq(sbd, &s->irq);
+
+ memory_region_init_io(&s->iomem, OBJECT(s), &aspeed_rtc_ops, s,
+ "aspeed-rtc", 0x18ULL);
+ sysbus_init_mmio(sbd, &s->iomem);
+}
+
+static void aspeed_rtc_class_init(ObjectClass *klass, void *data)
+{
+ DeviceClass *dc = DEVICE_CLASS(klass);
+
+ dc->realize = aspeed_rtc_realize;
+ dc->vmsd = &vmstate_aspeed_rtc;
+ dc->reset = aspeed_rtc_reset;
+}
+
+static const TypeInfo aspeed_rtc_info = {
+ .name = TYPE_ASPEED_RTC,
+ .parent = TYPE_SYS_BUS_DEVICE,
+ .instance_size = sizeof(AspeedRtcState),
+ .class_init = aspeed_rtc_class_init,
+};
+
+static void aspeed_rtc_register_types(void)
+{
+ type_register_static(&aspeed_rtc_info);
+}
+
+type_init(aspeed_rtc_register_types)