hw/timer: RX62N compare match timer (CMT)

renesas_cmt: 16bit compare match timer modules.
This part use many renesas's CPU.
Hardware manual.
https://www.renesas.com/us/en/doc/products/mpumcu/doc/rx_family/r01uh0033ej0140_rx62n.pdf

Signed-off-by: Yoshinori Sato <ysato@users.sourceforge.jp>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20200224141923.82118-16-ysato@users.sourceforge.jp>
[PMD: Split from TMR, filled VMStateField for migration]
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>

1 files changed, 283 insertions, 0 deletions

diff --git a/hw/timer/renesas_cmt.c b/hw/timer/renesas_cmt.c
new file mode 100644
index 0000000..2e0fd21
--- /dev/null
+++ b/hw/timer/renesas_cmt.c
@@ -0,0 +1,283 @@
+/*
+ * Renesas 16bit Compare-match timer
+ *
+ * Datasheet: RX62N Group, RX621 Group User's Manual: Hardware
+ *            (Rev.1.40 R01UH0033EJ0140)
+ *
+ * Copyright (c) 2019 Yoshinori Sato
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2 or later, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "qemu/osdep.h"
+#include "qemu/log.h"
+#include "hw/irq.h"
+#include "hw/registerfields.h"
+#include "hw/qdev-properties.h"
+#include "hw/timer/renesas_cmt.h"
+#include "migration/vmstate.h"
+
+/*
+ *  +0 CMSTR - common control
+ *  +2 CMCR  - ch0
+ *  +4 CMCNT - ch0
+ *  +6 CMCOR - ch0
+ *  +8 CMCR  - ch1
+ * +10 CMCNT - ch1
+ * +12 CMCOR - ch1
+ * If we think that the address of CH 0 has an offset of +2,
+ * we can treat it with the same address as CH 1, so define it like that.
+ */
+REG16(CMSTR, 0)
+  FIELD(CMSTR, STR0, 0, 1)
+  FIELD(CMSTR, STR1, 1, 1)
+  FIELD(CMSTR, STR,  0, 2)
+/* This addeess is channel offset */
+REG16(CMCR, 0)
+  FIELD(CMCR, CKS,  0, 2)
+  FIELD(CMCR, CMIE, 6, 1)
+REG16(CMCNT, 2)
+REG16(CMCOR, 4)
+
+static void update_events(RCMTState *cmt, int ch)
+{
+    int64_t next_time;
+
+    if ((cmt->cmstr & (1 << ch)) == 0) {
+        /* count disable, so not happened next event. */
+        return ;
+    }
+    next_time = cmt->cmcor[ch] - cmt->cmcnt[ch];
+    next_time *= NANOSECONDS_PER_SECOND;
+    next_time /= cmt->input_freq;
+    /*
+     * CKS -> div rate
+     *  0 -> 8 (1 << 3)
+     *  1 -> 32 (1 << 5)
+     *  2 -> 128 (1 << 7)
+     *  3 -> 512 (1 << 9)
+     */
+    next_time *= 1 << (3 + FIELD_EX16(cmt->cmcr[ch], CMCR, CKS) * 2);
+    next_time += qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
+    timer_mod(&cmt->timer[ch], next_time);
+}
+
+static int64_t read_cmcnt(RCMTState *cmt, int ch)
+{
+    int64_t delta, now = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
+
+    if (cmt->cmstr & (1 << ch)) {
+        delta = (now - cmt->tick[ch]);
+        delta /= NANOSECONDS_PER_SECOND;
+        delta /= cmt->input_freq;
+        delta /= 1 << (3 + FIELD_EX16(cmt->cmcr[ch], CMCR, CKS) * 2);
+        cmt->tick[ch] = now;
+        return cmt->cmcnt[ch] + delta;
+    } else {
+        return cmt->cmcnt[ch];
+    }
+}
+
+static uint64_t cmt_read(void *opaque, hwaddr offset, unsigned size)
+{
+    RCMTState *cmt = opaque;
+    int ch = offset / 0x08;
+    uint64_t ret;
+
+    if (offset == A_CMSTR) {
+        ret = 0;
+        ret = FIELD_DP16(ret, CMSTR, STR,
+                         FIELD_EX16(cmt->cmstr, CMSTR, STR));
+        return ret;
+    } else {
+        offset &= 0x07;
+        if (ch == 0) {
+            offset -= 0x02;
+        }
+        switch (offset) {
+        case A_CMCR:
+            ret = 0;
+            ret = FIELD_DP16(ret, CMCR, CKS,
+                             FIELD_EX16(cmt->cmstr, CMCR, CKS));
+            ret = FIELD_DP16(ret, CMCR, CMIE,
+                             FIELD_EX16(cmt->cmstr, CMCR, CMIE));
+            return ret;
+        case A_CMCNT:
+            return read_cmcnt(cmt, ch);
+        case A_CMCOR:
+            return cmt->cmcor[ch];
+        }
+    }
+    qemu_log_mask(LOG_UNIMP, "renesas_cmt: Register 0x%" HWADDR_PRIX " "
+                             "not implemented\n",
+                  offset);
+    return UINT64_MAX;
+}
+
+static void start_stop(RCMTState *cmt, int ch, int st)
+{
+    if (st) {
+        update_events(cmt, ch);
+    } else {
+        timer_del(&cmt->timer[ch]);
+    }
+}
+
+static void cmt_write(void *opaque, hwaddr offset, uint64_t val, unsigned size)
+{
+    RCMTState *cmt = opaque;
+    int ch = offset / 0x08;
+
+    if (offset == A_CMSTR) {
+        cmt->cmstr = FIELD_EX16(val, CMSTR, STR);
+        start_stop(cmt, 0, FIELD_EX16(cmt->cmstr, CMSTR, STR0));
+        start_stop(cmt, 1, FIELD_EX16(cmt->cmstr, CMSTR, STR1));
+    } else {
+        offset &= 0x07;
+        if (ch == 0) {
+            offset -= 0x02;
+        }
+        switch (offset) {
+        case A_CMCR:
+            cmt->cmcr[ch] = FIELD_DP16(cmt->cmcr[ch], CMCR, CKS,
+                                       FIELD_EX16(val, CMCR, CKS));
+            cmt->cmcr[ch] = FIELD_DP16(cmt->cmcr[ch], CMCR, CMIE,
+                                       FIELD_EX16(val, CMCR, CMIE));
+            break;
+        case 2:
+            cmt->cmcnt[ch] = val;
+            break;
+        case 4:
+            cmt->cmcor[ch] = val;
+            break;
+        default:
+            qemu_log_mask(LOG_UNIMP, "renesas_cmt: Register 0x%" HWADDR_PRIX " "
+                                     "not implemented\n",
+                          offset);
+            return;
+        }
+        if (FIELD_EX16(cmt->cmstr, CMSTR, STR) & (1 << ch)) {
+            update_events(cmt, ch);
+        }
+    }
+}
+
+static const MemoryRegionOps cmt_ops = {
+    .write = cmt_write,
+    .read  = cmt_read,
+    .endianness = DEVICE_NATIVE_ENDIAN,
+    .impl = {
+        .min_access_size = 2,
+        .max_access_size = 2,
+    },
+    .valid = {
+        .min_access_size = 2,
+        .max_access_size = 2,
+    },
+};
+
+static void timer_events(RCMTState *cmt, int ch)
+{
+    cmt->cmcnt[ch] = 0;
+    cmt->tick[ch] = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
+    update_events(cmt, ch);
+    if (FIELD_EX16(cmt->cmcr[ch], CMCR, CMIE)) {
+        qemu_irq_pulse(cmt->cmi[ch]);
+    }
+}
+
+static void timer_event0(void *opaque)
+{
+    RCMTState *cmt = opaque;
+
+    timer_events(cmt, 0);
+}
+
+static void timer_event1(void *opaque)
+{
+    RCMTState *cmt = opaque;
+
+    timer_events(cmt, 1);
+}
+
+static void rcmt_reset(DeviceState *dev)
+{
+    RCMTState *cmt = RCMT(dev);
+    cmt->cmstr = 0;
+    cmt->cmcr[0] = cmt->cmcr[1] = 0;
+    cmt->cmcnt[0] = cmt->cmcnt[1] = 0;
+    cmt->cmcor[0] = cmt->cmcor[1] = 0xffff;
+}
+
+static void rcmt_init(Object *obj)
+{
+    SysBusDevice *d = SYS_BUS_DEVICE(obj);
+    RCMTState *cmt = RCMT(obj);
+    int i;
+
+    memory_region_init_io(&cmt->memory, OBJECT(cmt), &cmt_ops,
+                          cmt, "renesas-cmt", 0x10);
+    sysbus_init_mmio(d, &cmt->memory);
+
+    for (i = 0; i < ARRAY_SIZE(cmt->cmi); i++) {
+        sysbus_init_irq(d, &cmt->cmi[i]);
+    }
+    timer_init_ns(&cmt->timer[0], QEMU_CLOCK_VIRTUAL, timer_event0, cmt);
+    timer_init_ns(&cmt->timer[1], QEMU_CLOCK_VIRTUAL, timer_event1, cmt);
+}
+
+static const VMStateDescription vmstate_rcmt = {
+    .name = "rx-cmt",
+    .version_id = 1,
+    .minimum_version_id = 1,
+    .fields = (VMStateField[]) {
+        VMSTATE_UINT16(cmstr, RCMTState),
+        VMSTATE_UINT16_ARRAY(cmcr, RCMTState, CMT_CH),
+        VMSTATE_UINT16_ARRAY(cmcnt, RCMTState, CMT_CH),
+        VMSTATE_UINT16_ARRAY(cmcor, RCMTState, CMT_CH),
+        VMSTATE_INT64_ARRAY(tick, RCMTState, CMT_CH),
+        VMSTATE_TIMER_ARRAY(timer, RCMTState, CMT_CH),
+        VMSTATE_END_OF_LIST()
+    }
+};
+
+static Property rcmt_properties[] = {
+    DEFINE_PROP_UINT64("input-freq", RCMTState, input_freq, 0),
+    DEFINE_PROP_END_OF_LIST(),
+};
+
+static void rcmt_class_init(ObjectClass *klass, void *data)
+{
+    DeviceClass *dc = DEVICE_CLASS(klass);
+
+    dc->vmsd = &vmstate_rcmt;
+    dc->reset = rcmt_reset;
+    device_class_set_props(dc, rcmt_properties);
+}
+
+static const TypeInfo rcmt_info = {
+    .name = TYPE_RENESAS_CMT,
+    .parent = TYPE_SYS_BUS_DEVICE,
+    .instance_size = sizeof(RCMTState),
+    .instance_init = rcmt_init,
+    .class_init = rcmt_class_init,
+};
+
+static void rcmt_register_types(void)
+{
+    type_register_static(&rcmt_info);
+}
+
+type_init(rcmt_register_types)