msf2: Add Smartfusion2 System timer

Modelled System Timer in Microsemi's Smartfusion2 Soc.
Timer has two 32bit down counters and two interrupts.

Signed-off-by: Subbaraya Sundeep <sundeep.lkml@gmail.com>
Reviewed-by: Alistair Francis <alistair.francis@xilinx.com>
Acked-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Tested-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 20170920201737.25723-2-f4bug@amsat.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

3 files changed, 354 insertions, 0 deletions

diff --git a/hw/timer/Makefile.objs b/hw/timer/Makefile.objs
index 15cce1c531..8c19eac3b6 100644
--- a/hw/timer/Makefile.objs
+++ b/hw/timer/Makefile.objs
@@ -42,3 +42,4 @@ common-obj-$(CONFIG_ASPEED_SOC) += aspeed_timer.o
 
 common-obj-$(CONFIG_SUN4V_RTC) += sun4v-rtc.o
 common-obj-$(CONFIG_CMSDK_APB_TIMER) += cmsdk-apb-timer.o
+common-obj-$(CONFIG_MSF2) += mss-timer.o
diff --git a/hw/timer/mss-timer.c b/hw/timer/mss-timer.c
new file mode 100644
index 0000000000..60f1213a3b
--- /dev/null
+++ b/hw/timer/mss-timer.c
@@ -0,0 +1,289 @@
+/*
+ * Block model of System timer present in
+ * Microsemi's SmartFusion2 and SmartFusion SoCs.
+ *
+ * Copyright (c) 2017 Subbaraya Sundeep <sundeep.lkml@gmail.com>.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include "qemu/osdep.h"
+#include "qemu/main-loop.h"
+#include "qemu/log.h"
+#include "hw/timer/mss-timer.h"
+
+#ifndef MSS_TIMER_ERR_DEBUG
+#define MSS_TIMER_ERR_DEBUG  0
+#endif
+
+#define DB_PRINT_L(lvl, fmt, args...) do { \
+    if (MSS_TIMER_ERR_DEBUG >= lvl) { \
+        qemu_log("%s: " fmt "\n", __func__, ## args); \
+    } \
+} while (0);
+
+#define DB_PRINT(fmt, args...) DB_PRINT_L(1, fmt, ## args)
+
+#define R_TIM_VAL         0
+#define R_TIM_LOADVAL     1
+#define R_TIM_BGLOADVAL   2
+#define R_TIM_CTRL        3
+#define R_TIM_RIS         4
+#define R_TIM_MIS         5
+
+#define TIMER_CTRL_ENBL     (1 << 0)
+#define TIMER_CTRL_ONESHOT  (1 << 1)
+#define TIMER_CTRL_INTR     (1 << 2)
+#define TIMER_RIS_ACK       (1 << 0)
+#define TIMER_RST_CLR       (1 << 6)
+#define TIMER_MODE          (1 << 0)
+
+static void timer_update_irq(struct Msf2Timer *st)
+{
+    bool isr, ier;
+
+    isr = !!(st->regs[R_TIM_RIS] & TIMER_RIS_ACK);
+    ier = !!(st->regs[R_TIM_CTRL] & TIMER_CTRL_INTR);
+    qemu_set_irq(st->irq, (ier && isr));
+}
+
+static void timer_update(struct Msf2Timer *st)
+{
+    uint64_t count;
+
+    if (!(st->regs[R_TIM_CTRL] & TIMER_CTRL_ENBL)) {
+        ptimer_stop(st->ptimer);
+        return;
+    }
+
+    count = st->regs[R_TIM_LOADVAL];
+    ptimer_set_limit(st->ptimer, count, 1);
+    ptimer_run(st->ptimer, 1);
+}
+
+static uint64_t
+timer_read(void *opaque, hwaddr offset, unsigned int size)
+{
+    MSSTimerState *t = opaque;
+    hwaddr addr;
+    struct Msf2Timer *st;
+    uint32_t ret = 0;
+    int timer = 0;
+    int isr;
+    int ier;
+
+    addr = offset >> 2;
+    /*
+     * Two independent timers has same base address.
+     * Based on address passed figure out which timer is being used.
+     */
+    if ((addr >= R_TIM1_MAX) && (addr < NUM_TIMERS * R_TIM1_MAX)) {
+        timer = 1;
+        addr -= R_TIM1_MAX;
+    }
+
+    st = &t->timers[timer];
+
+    switch (addr) {
+    case R_TIM_VAL:
+        ret = ptimer_get_count(st->ptimer);
+        break;
+
+    case R_TIM_MIS:
+        isr = !!(st->regs[R_TIM_RIS] & TIMER_RIS_ACK);
+        ier = !!(st->regs[R_TIM_CTRL] & TIMER_CTRL_INTR);
+        ret = ier & isr;
+        break;
+
+    default:
+        if (addr < R_TIM1_MAX) {
+            ret = st->regs[addr];
+        } else {
+            qemu_log_mask(LOG_GUEST_ERROR,
+                        TYPE_MSS_TIMER": 64-bit mode not supported\n");
+            return ret;
+        }
+        break;
+    }
+
+    DB_PRINT("timer=%d 0x%" HWADDR_PRIx "=0x%" PRIx32, timer, offset,
+            ret);
+    return ret;
+}
+
+static void
+timer_write(void *opaque, hwaddr offset,
+            uint64_t val64, unsigned int size)
+{
+    MSSTimerState *t = opaque;
+    hwaddr addr;
+    struct Msf2Timer *st;
+    int timer = 0;
+    uint32_t value = val64;
+
+    addr = offset >> 2;
+    /*
+     * Two independent timers has same base address.
+     * Based on addr passed figure out which timer is being used.
+     */
+    if ((addr >= R_TIM1_MAX) && (addr < NUM_TIMERS * R_TIM1_MAX)) {
+        timer = 1;
+        addr -= R_TIM1_MAX;
+    }
+
+    st = &t->timers[timer];
+
+    DB_PRINT("addr=0x%" HWADDR_PRIx " val=0x%" PRIx32 " (timer=%d)", offset,
+            value, timer);
+
+    switch (addr) {
+    case R_TIM_CTRL:
+        st->regs[R_TIM_CTRL] = value;
+        timer_update(st);
+        break;
+
+    case R_TIM_RIS:
+        if (value & TIMER_RIS_ACK) {
+            st->regs[R_TIM_RIS] &= ~TIMER_RIS_ACK;
+        }
+        break;
+
+    case R_TIM_LOADVAL:
+        st->regs[R_TIM_LOADVAL] = value;
+        if (st->regs[R_TIM_CTRL] & TIMER_CTRL_ENBL) {
+            timer_update(st);
+        }
+        break;
+
+    case R_TIM_BGLOADVAL:
+        st->regs[R_TIM_BGLOADVAL] = value;
+        st->regs[R_TIM_LOADVAL] = value;
+        break;
+
+    case R_TIM_VAL:
+    case R_TIM_MIS:
+        break;
+
+    default:
+        if (addr < R_TIM1_MAX) {
+            st->regs[addr] = value;
+        } else {
+            qemu_log_mask(LOG_GUEST_ERROR,
+                        TYPE_MSS_TIMER": 64-bit mode not supported\n");
+            return;
+        }
+        break;
+    }
+    timer_update_irq(st);
+}
+
+static const MemoryRegionOps timer_ops = {
+    .read = timer_read,
+    .write = timer_write,
+    .endianness = DEVICE_NATIVE_ENDIAN,
+    .valid = {
+        .min_access_size = 1,
+        .max_access_size = 4
+    }
+};
+
+static void timer_hit(void *opaque)
+{
+    struct Msf2Timer *st = opaque;
+
+    st->regs[R_TIM_RIS] |= TIMER_RIS_ACK;
+
+    if (!(st->regs[R_TIM_CTRL] & TIMER_CTRL_ONESHOT)) {
+        timer_update(st);
+    }
+    timer_update_irq(st);
+}
+
+static void mss_timer_init(Object *obj)
+{
+    MSSTimerState *t = MSS_TIMER(obj);
+    int i;
+
+    /* Init all the ptimers.  */
+    for (i = 0; i < NUM_TIMERS; i++) {
+        struct Msf2Timer *st = &t->timers[i];
+
+        st->bh = qemu_bh_new(timer_hit, st);
+        st->ptimer = ptimer_init(st->bh, PTIMER_POLICY_DEFAULT);
+        ptimer_set_freq(st->ptimer, t->freq_hz);
+        sysbus_init_irq(SYS_BUS_DEVICE(obj), &st->irq);
+    }
+
+    memory_region_init_io(&t->mmio, OBJECT(t), &timer_ops, t, TYPE_MSS_TIMER,
+                          NUM_TIMERS * R_TIM1_MAX * 4);
+    sysbus_init_mmio(SYS_BUS_DEVICE(obj), &t->mmio);
+}
+
+static const VMStateDescription vmstate_timers = {
+    .name = "mss-timer-block",
+    .version_id = 1,
+    .minimum_version_id = 1,
+    .fields = (VMStateField[]) {
+        VMSTATE_PTIMER(ptimer, struct Msf2Timer),
+        VMSTATE_UINT32_ARRAY(regs, struct Msf2Timer, R_TIM1_MAX),
+        VMSTATE_END_OF_LIST()
+    }
+};
+
+static const VMStateDescription vmstate_mss_timer = {
+    .name = TYPE_MSS_TIMER,
+    .version_id = 1,
+    .minimum_version_id = 1,
+    .fields = (VMStateField[]) {
+        VMSTATE_UINT32(freq_hz, MSSTimerState),
+        VMSTATE_STRUCT_ARRAY(timers, MSSTimerState, NUM_TIMERS, 0,
+                vmstate_timers, struct Msf2Timer),
+        VMSTATE_END_OF_LIST()
+    }
+};
+
+static Property mss_timer_properties[] = {
+    /* Libero GUI shows 100Mhz as default for clocks */
+    DEFINE_PROP_UINT32("clock-frequency", MSSTimerState, freq_hz,
+                      100 * 1000000),
+    DEFINE_PROP_END_OF_LIST(),
+};
+
+static void mss_timer_class_init(ObjectClass *klass, void *data)
+{
+    DeviceClass *dc = DEVICE_CLASS(klass);
+
+    dc->props = mss_timer_properties;
+    dc->vmsd = &vmstate_mss_timer;
+}
+
+static const TypeInfo mss_timer_info = {
+    .name          = TYPE_MSS_TIMER,
+    .parent        = TYPE_SYS_BUS_DEVICE,
+    .instance_size = sizeof(MSSTimerState),
+    .instance_init = mss_timer_init,
+    .class_init    = mss_timer_class_init,
+};
+
+static void mss_timer_register_types(void)
+{
+    type_register_static(&mss_timer_info);
+}
+
+type_init(mss_timer_register_types)
diff --git a/include/hw/timer/mss-timer.h b/include/hw/timer/mss-timer.h
new file mode 100644
index 0000000000..d15d1732f8
--- /dev/null
+++ b/include/hw/timer/mss-timer.h
@@ -0,0 +1,64 @@
+/*
+ * Microsemi SmartFusion2 Timer.
+ *
+ * Copyright (c) 2017 Subbaraya Sundeep <sundeep.lkml@gmail.com>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#ifndef HW_MSS_TIMER_H
+#define HW_MSS_TIMER_H
+
+#include "hw/sysbus.h"
+#include "hw/ptimer.h"
+
+#define TYPE_MSS_TIMER     "mss-timer"
+#define MSS_TIMER(obj)     OBJECT_CHECK(MSSTimerState, \
+                              (obj), TYPE_MSS_TIMER)
+
+/*
+ * There are two 32-bit down counting timers.
+ * Timers 1 and 2 can be concatenated into a single 64-bit Timer
+ * that operates either in Periodic mode or in One-shot mode.
+ * Writing 1 to the TIM64_MODE register bit 0 sets the Timers in 64-bit mode.
+ * In 64-bit mode, writing to the 32-bit registers has no effect.
+ * Similarly, in 32-bit mode, writing to the 64-bit mode registers
+ * has no effect. Only two 32-bit timers are supported currently.
+ */
+#define NUM_TIMERS        2
+
+#define R_TIM1_MAX        6
+
+struct Msf2Timer {
+    QEMUBH *bh;
+    ptimer_state *ptimer;
+
+    uint32_t regs[R_TIM1_MAX];
+    qemu_irq irq;
+};
+
+typedef struct MSSTimerState {
+    SysBusDevice parent_obj;
+
+    MemoryRegion mmio;
+    uint32_t freq_hz;
+    struct Msf2Timer timers[NUM_TIMERS];
+} MSSTimerState;
+
+#endif /* HW_MSS_TIMER_H */