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* [PATCH v3 0/2] RTC support for QEMU RISC-V virt machine
@ 2019-10-15  8:35 Anup Patel
  2019-10-15  8:35 ` [PATCH v3 1/2] hw: timer: Add Goldfish RTC device Anup Patel
  2019-10-15  8:35 ` [PATCH v3 2/2] riscv: virt: Use " Anup Patel
  0 siblings, 2 replies; 11+ messages in thread
From: Anup Patel @ 2019-10-15  8:35 UTC (permalink / raw)
  To: Peter Maydell, Palmer Dabbelt, Alistair Francis, Sagar Karandikar,
	Bastian Koppelmann
  Cc: Atish Patra, Anup Patel, qemu-riscv@nongnu.org,
	qemu-devel@nongnu.org, Anup Patel

This series adds RTC device to QEMU RISC-V virt machine. We have
selected Goldfish RTC device model for this. It's a pretty simple
synthetic device with few MMIO registers and no dependency external
clock. The driver for Goldfish RTC is already available in Linux so
we just need to enable it in Kconfig for RISCV and also update Linux
defconfigs.

We have tested this series with Linux-5.4-rc1 plus defconfig changes
available in 'goldfish_rtc_v2' branch of:
https://github.com/avpatel/linux.git

Changes since v2:
 - Rebased patches on recent RTC refactoring by Philippe Mathieu-Daud??
   (Refer, https://patchew.org/QEMU/20191003230404.19384-1-philmd@redhat.com/)

Changes since v1:
 - Implemented VMState save/restore for Goldfish RTC

Anup Patel (2):
  hw: timer: Add Goldfish RTC device
  riscv: virt: Use Goldfish RTC device

 hw/riscv/Kconfig                |   1 +
 hw/riscv/virt.c                 |  15 ++
 hw/rtc/Kconfig                  |   3 +
 hw/rtc/Makefile.objs            |   1 +
 hw/rtc/goldfish_rtc.c           | 278 ++++++++++++++++++++++++++++++++
 include/hw/riscv/virt.h         |   2 +
 include/hw/timer/goldfish_rtc.h |  46 ++++++
 7 files changed, 346 insertions(+)
 create mode 100644 hw/rtc/goldfish_rtc.c
 create mode 100644 include/hw/timer/goldfish_rtc.h

--
2.17.1


^ permalink raw reply	[flat|nested] 11+ messages in thread

* [PATCH v3 1/2] hw: timer: Add Goldfish RTC device
  2019-10-15  8:35 [PATCH v3 0/2] RTC support for QEMU RISC-V virt machine Anup Patel
@ 2019-10-15  8:35 ` Anup Patel
  2019-10-18 18:52   ` Palmer Dabbelt
                     ` (2 more replies)
  2019-10-15  8:35 ` [PATCH v3 2/2] riscv: virt: Use " Anup Patel
  1 sibling, 3 replies; 11+ messages in thread
From: Anup Patel @ 2019-10-15  8:35 UTC (permalink / raw)
  To: Peter Maydell, Palmer Dabbelt, Alistair Francis, Sagar Karandikar,
	Bastian Koppelmann
  Cc: Atish Patra, Anup Patel, qemu-riscv@nongnu.org,
	qemu-devel@nongnu.org, Anup Patel

This patch adds model for Google Goldfish virtual platform RTC device.

We will be adding Goldfish RTC device to the QEMU RISC-V virt machine
for providing real date-time to Guest Linux. The corresponding Linux
driver for Goldfish RTC device is already available in upstream Linux.

For now, VM migration support is available but untested for Goldfish RTC
device. It will be hardened in-future when we implement VM migration for
KVM RISC-V.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
---
 hw/rtc/Kconfig                  |   3 +
 hw/rtc/Makefile.objs            |   1 +
 hw/rtc/goldfish_rtc.c           | 278 ++++++++++++++++++++++++++++++++
 include/hw/timer/goldfish_rtc.h |  46 ++++++
 4 files changed, 328 insertions(+)
 create mode 100644 hw/rtc/goldfish_rtc.c
 create mode 100644 include/hw/timer/goldfish_rtc.h

diff --git a/hw/rtc/Kconfig b/hw/rtc/Kconfig
index 45daa8d655..bafe6ac2c9 100644
--- a/hw/rtc/Kconfig
+++ b/hw/rtc/Kconfig
@@ -21,3 +21,6 @@ config MC146818RTC
 
 config SUN4V_RTC
     bool
+
+config GOLDFISH_RTC
+    bool
diff --git a/hw/rtc/Makefile.objs b/hw/rtc/Makefile.objs
index 8dc9fcd3a9..aa208d0d10 100644
--- a/hw/rtc/Makefile.objs
+++ b/hw/rtc/Makefile.objs
@@ -11,3 +11,4 @@ common-obj-$(CONFIG_EXYNOS4) += exynos4210_rtc.o
 obj-$(CONFIG_MC146818RTC) += mc146818rtc.o
 common-obj-$(CONFIG_SUN4V_RTC) += sun4v-rtc.o
 common-obj-$(CONFIG_ASPEED_SOC) += aspeed_rtc.o
+common-obj-$(CONFIG_GOLDFISH_RTC) += goldfish_rtc.o
diff --git a/hw/rtc/goldfish_rtc.c b/hw/rtc/goldfish_rtc.c
new file mode 100644
index 0000000000..223616ed75
--- /dev/null
+++ b/hw/rtc/goldfish_rtc.c
@@ -0,0 +1,278 @@
+/*
+ * Goldfish virtual platform RTC
+ *
+ * Copyright (C) 2019 Western Digital Corporation or its affiliates.
+ *
+ * For more details on Google Goldfish virtual platform refer:
+ * https://android.googlesource.com/platform/external/qemu/+/master/docs/GOLDFISH-VIRTUAL-HARDWARE.TXT
+ *
+ * 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-common.h"
+#include "hw/timer/goldfish_rtc.h"
+#include "migration/vmstate.h"
+#include "hw/irq.h"
+#include "hw/qdev-properties.h"
+#include "hw/sysbus.h"
+#include "qemu/timer.h"
+#include "sysemu/sysemu.h"
+#include "qemu/cutils.h"
+#include "qemu/log.h"
+
+#define RTC_TIME_LOW            0x00
+#define RTC_TIME_HIGH           0x04
+#define RTC_ALARM_LOW           0x08
+#define RTC_ALARM_HIGH          0x0c
+#define RTC_IRQ_ENABLED         0x10
+#define RTC_CLEAR_ALARM         0x14
+#define RTC_ALARM_STATUS        0x18
+#define RTC_CLEAR_INTERRUPT     0x1c
+
+static void goldfish_rtc_update(GoldfishRTCState *s)
+{
+    qemu_set_irq(s->irq, (s->irq_pending & s->irq_enabled) ? 1 : 0);
+}
+
+static void goldfish_rtc_interrupt(void *opaque)
+{
+    GoldfishRTCState *s = (GoldfishRTCState *)opaque;
+
+    s->alarm_running = 0;
+    s->irq_pending = 1;
+    goldfish_rtc_update(s);
+}
+
+static uint64_t goldfish_rtc_get_count(GoldfishRTCState *s)
+{
+    return s->tick_offset + (uint64_t)qemu_clock_get_ns(rtc_clock);
+}
+
+static void goldfish_rtc_clear_alarm(GoldfishRTCState *s)
+{
+    timer_del(s->timer);
+    s->alarm_running = 0;
+}
+
+static void goldfish_rtc_set_alarm(GoldfishRTCState *s)
+{
+    uint64_t ticks = goldfish_rtc_get_count(s);
+    uint64_t event = s->alarm_next;
+
+    if (event <= ticks) {
+        goldfish_rtc_clear_alarm(s);
+        goldfish_rtc_interrupt(s);
+    } else {
+        int64_t now = qemu_clock_get_ns(rtc_clock);
+        timer_mod(s->timer, now + (event - ticks));
+        s->alarm_running = 1;
+    }
+}
+
+static uint64_t goldfish_rtc_read(void *opaque, hwaddr offset,
+                                  unsigned size)
+{
+    GoldfishRTCState *s = (GoldfishRTCState *)opaque;
+    uint64_t r;
+
+    switch (offset) {
+    case RTC_TIME_LOW:
+        r = goldfish_rtc_get_count(s) & 0xffffffff;
+        break;
+    case RTC_TIME_HIGH:
+        r = goldfish_rtc_get_count(s) >> 32;
+        break;
+    case RTC_ALARM_LOW:
+        r = s->alarm_next & 0xffffffff;
+        break;
+    case RTC_ALARM_HIGH:
+        r = s->alarm_next >> 32;
+        break;
+    case RTC_IRQ_ENABLED:
+        r = s->irq_enabled;
+        break;
+    case RTC_ALARM_STATUS:
+        r = s->alarm_running;
+        break;
+    default:
+        qemu_log_mask(LOG_GUEST_ERROR,
+                      "goldfish_rtc_read: Bad offset 0x%x\n", (int)offset);
+        r = 0;
+        break;
+    }
+
+    return r;
+}
+
+static void goldfish_rtc_write(void *opaque, hwaddr offset,
+                               uint64_t value, unsigned size)
+{
+    uint64_t current_tick, new_tick;
+    GoldfishRTCState *s = (GoldfishRTCState *)opaque;
+
+    switch (offset) {
+    case RTC_TIME_LOW:
+        current_tick = goldfish_rtc_get_count(s);
+        new_tick = current_tick & (0xffffffffULL << 32);
+        new_tick |= value;
+        s->tick_offset += new_tick - current_tick;
+        break;
+    case RTC_TIME_HIGH:
+        current_tick = goldfish_rtc_get_count(s);
+        new_tick = current_tick & 0xffffffffULL;
+        new_tick |= (value << 32);
+        s->tick_offset += new_tick - current_tick;
+        break;
+    case RTC_ALARM_LOW:
+        s->alarm_next &= (0xffffffffULL << 32);
+        s->alarm_next |= value;
+        goldfish_rtc_set_alarm(s);
+        break;
+    case RTC_ALARM_HIGH:
+        s->alarm_next &= 0xffffffffULL;
+        s->alarm_next |= (value << 32);
+        break;
+    case RTC_IRQ_ENABLED:
+        s->irq_enabled = (uint32_t)(value & 0x1);
+        goldfish_rtc_update(s);
+        break;
+    case RTC_CLEAR_ALARM:
+        goldfish_rtc_clear_alarm(s);
+        break;
+    case RTC_CLEAR_INTERRUPT:
+        s->irq_pending = 0;
+        goldfish_rtc_update(s);
+        break;
+    default:
+        qemu_log_mask(LOG_GUEST_ERROR,
+                      "goldfish_rtc_write: Bad offset 0x%x\n", (int)offset);
+        break;
+    }
+}
+
+static int goldfish_rtc_pre_save(void *opaque)
+{
+    uint64_t delta;
+    GoldfishRTCState *s = opaque;
+
+    /*
+     * We want to migrate this offset, which sounds straightforward.
+     * Unfortunately, we cannot directly pass tick_offset because
+     * rtc_clock on destinetion Host might not be same source Host.
+     *
+     * To tackle, this we pass tick_offset relative to vm_clock from
+     * source Host and make it relative to rtc_clock at destinetion Host.
+     */
+    delta = qemu_clock_get_ns(rtc_clock) -
+            qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
+    s->tick_offset_vmstate = s->tick_offset + delta;
+
+    return 0;
+}
+
+static int goldfish_rtc_post_load(void *opaque, int version_id)
+{
+    uint64_t delta;
+    GoldfishRTCState *s = opaque;
+
+    /*
+     * We extract tick_offset from tick_offset_vmstate by doing
+     * reverse math compared to pre_save() function.
+     */
+    delta = qemu_clock_get_ns(rtc_clock) -
+            qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
+    s->tick_offset = s->tick_offset_vmstate - delta;
+
+    return 0;
+}
+
+static const MemoryRegionOps goldfish_rtc_ops = {
+    .read = goldfish_rtc_read,
+    .write = goldfish_rtc_write,
+    .endianness = DEVICE_LITTLE_ENDIAN,
+    .valid = {
+        .min_access_size = 4,
+        .max_access_size = 4
+    }
+};
+
+static const VMStateDescription goldfish_rtc_vmstate = {
+    .name = TYPE_GOLDFISH_RTC,
+    .version_id = 1,
+    .pre_save = goldfish_rtc_pre_save,
+    .post_load = goldfish_rtc_post_load,
+    .fields = (VMStateField[]) {
+        VMSTATE_UINT64(tick_offset_vmstate, GoldfishRTCState),
+        VMSTATE_UINT64(alarm_next, GoldfishRTCState),
+        VMSTATE_UINT32(alarm_running, GoldfishRTCState),
+        VMSTATE_UINT32(irq_pending, GoldfishRTCState),
+        VMSTATE_UINT32(irq_enabled, GoldfishRTCState),
+        VMSTATE_END_OF_LIST()
+    }
+};
+
+static void goldfish_rtc_reset(DeviceState *dev)
+{
+    GoldfishRTCState *s = GOLDFISH_RTC(dev);
+    struct tm tm;
+
+    timer_del(s->timer);
+
+    qemu_get_timedate(&tm, 0);
+    s->tick_offset = mktimegm(&tm);
+    s->tick_offset *= NANOSECONDS_PER_SECOND;
+    s->tick_offset -= qemu_clock_get_ns(rtc_clock);
+    s->tick_offset_vmstate = 0;
+    s->alarm_next = 0;
+    s->alarm_running = 0;
+    s->irq_pending = 0;
+    s->irq_enabled = 0;
+}
+
+static void goldfish_rtc_realize(DeviceState *d, Error **errp)
+{
+    SysBusDevice *dev = SYS_BUS_DEVICE(d);
+    GoldfishRTCState *s = GOLDFISH_RTC(d);
+
+    memory_region_init_io(&s->iomem, OBJECT(s), &goldfish_rtc_ops, s,
+                          "goldfish_rtc", 0x1000);
+    sysbus_init_mmio(dev, &s->iomem);
+
+    sysbus_init_irq(dev, &s->irq);
+
+    s->timer = timer_new_ns(rtc_clock, goldfish_rtc_interrupt, s);
+}
+
+static void goldfish_rtc_class_init(ObjectClass *klass, void *data)
+{
+    DeviceClass *dc = DEVICE_CLASS(klass);
+
+    dc->realize = goldfish_rtc_realize;
+    dc->reset = goldfish_rtc_reset;
+    dc->vmsd = &goldfish_rtc_vmstate;
+}
+
+static const TypeInfo goldfish_rtc_info = {
+    .name          = TYPE_GOLDFISH_RTC,
+    .parent        = TYPE_SYS_BUS_DEVICE,
+    .instance_size = sizeof(GoldfishRTCState),
+    .class_init    = goldfish_rtc_class_init,
+};
+
+static void goldfish_rtc_register_types(void)
+{
+    type_register_static(&goldfish_rtc_info);
+}
+
+type_init(goldfish_rtc_register_types)
diff --git a/include/hw/timer/goldfish_rtc.h b/include/hw/timer/goldfish_rtc.h
new file mode 100644
index 0000000000..dfb6d70b86
--- /dev/null
+++ b/include/hw/timer/goldfish_rtc.h
@@ -0,0 +1,46 @@
+/*
+ * Goldfish virtual platform RTC
+ *
+ * Copyright (C) 2019 Western Digital Corporation or its affiliates.
+ *
+ * For more details on Google Goldfish virtual platform refer:
+ * https://android.googlesource.com/platform/external/qemu/+/master/docs/GOLDFISH-VIRTUAL-HARDWARE.TXT
+ *
+ * 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/>.
+ */
+
+#ifndef HW_TIMER_GOLDFISH_RTC_H
+#define HW_TIMER_GOLDFISH_RTC_H
+
+#include "hw/sysbus.h"
+
+#define TYPE_GOLDFISH_RTC "goldfish_rtc"
+#define GOLDFISH_RTC(obj) \
+OBJECT_CHECK(GoldfishRTCState, (obj), TYPE_GOLDFISH_RTC)
+
+typedef struct GoldfishRTCState {
+    SysBusDevice parent_obj;
+
+    MemoryRegion iomem;
+    QEMUTimer *timer;
+    qemu_irq irq;
+
+    uint64_t tick_offset;
+    uint64_t tick_offset_vmstate;
+    uint64_t alarm_next;
+    uint32_t alarm_running;
+    uint32_t irq_pending;
+    uint32_t irq_enabled;
+} GoldfishRTCState;
+
+#endif
-- 
2.17.1



^ permalink raw reply related	[flat|nested] 11+ messages in thread

* [PATCH v3 2/2] riscv: virt: Use Goldfish RTC device
  2019-10-15  8:35 [PATCH v3 0/2] RTC support for QEMU RISC-V virt machine Anup Patel
  2019-10-15  8:35 ` [PATCH v3 1/2] hw: timer: Add Goldfish RTC device Anup Patel
@ 2019-10-15  8:35 ` Anup Patel
  2019-10-18 18:52   ` Palmer Dabbelt
  2019-10-18 21:00   ` Alistair Francis
  1 sibling, 2 replies; 11+ messages in thread
From: Anup Patel @ 2019-10-15  8:35 UTC (permalink / raw)
  To: Peter Maydell, Palmer Dabbelt, Alistair Francis, Sagar Karandikar,
	Bastian Koppelmann
  Cc: Atish Patra, Anup Patel, qemu-riscv@nongnu.org,
	qemu-devel@nongnu.org, Anup Patel

We extend QEMU RISC-V virt machine by adding Goldfish RTC device
to it. This will allow Guest Linux to sync it's local date/time
with Host date/time via RTC device.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
---
 hw/riscv/Kconfig        |  1 +
 hw/riscv/virt.c         | 15 +++++++++++++++
 include/hw/riscv/virt.h |  2 ++
 3 files changed, 18 insertions(+)

diff --git a/hw/riscv/Kconfig b/hw/riscv/Kconfig
index fb19b2df3a..b33753c780 100644
--- a/hw/riscv/Kconfig
+++ b/hw/riscv/Kconfig
@@ -34,6 +34,7 @@ config RISCV_VIRT
     select PCI
     select HART
     select SERIAL
+    select GOLDFISH_RTC
     select VIRTIO_MMIO
     select PCI_EXPRESS_GENERIC_BRIDGE
     select SIFIVE
diff --git a/hw/riscv/virt.c b/hw/riscv/virt.c
index d36f5625ec..95c42ab993 100644
--- a/hw/riscv/virt.c
+++ b/hw/riscv/virt.c
@@ -57,6 +57,7 @@ static const struct MemmapEntry {
     [VIRT_DEBUG] =       {        0x0,         0x100 },
     [VIRT_MROM] =        {     0x1000,       0x11000 },
     [VIRT_TEST] =        {   0x100000,        0x1000 },
+    [VIRT_RTC] =         {   0x101000,        0x1000 },
     [VIRT_CLINT] =       {  0x2000000,       0x10000 },
     [VIRT_PLIC] =        {  0xc000000,     0x4000000 },
     [VIRT_UART0] =       { 0x10000000,         0x100 },
@@ -310,6 +311,17 @@ static void create_fdt(RISCVVirtState *s, const struct MemmapEntry *memmap,
     qemu_fdt_setprop_cell(fdt, nodename, "interrupt-parent", plic_phandle);
     qemu_fdt_setprop_cell(fdt, nodename, "interrupts", UART0_IRQ);
 
+    nodename = g_strdup_printf("/rtc@%lx",
+        (long)memmap[VIRT_RTC].base);
+    qemu_fdt_add_subnode(fdt, nodename);
+    qemu_fdt_setprop_string(fdt, nodename, "compatible",
+        "google,goldfish-rtc");
+    qemu_fdt_setprop_cells(fdt, nodename, "reg",
+        0x0, memmap[VIRT_RTC].base,
+        0x0, memmap[VIRT_RTC].size);
+    qemu_fdt_setprop_cell(fdt, nodename, "interrupt-parent", plic_phandle);
+    qemu_fdt_setprop_cell(fdt, nodename, "interrupts", RTC_IRQ);
+
     qemu_fdt_add_subnode(fdt, "/chosen");
     qemu_fdt_setprop_string(fdt, "/chosen", "stdout-path", nodename);
     if (cmdline) {
@@ -496,6 +508,9 @@ static void riscv_virt_board_init(MachineState *machine)
         0, qdev_get_gpio_in(DEVICE(s->plic), UART0_IRQ), 399193,
         serial_hd(0), DEVICE_LITTLE_ENDIAN);
 
+    sysbus_create_simple("goldfish_rtc", memmap[VIRT_RTC].base,
+        qdev_get_gpio_in(DEVICE(s->plic), RTC_IRQ));
+
     g_free(plic_hart_config);
 }
 
diff --git a/include/hw/riscv/virt.h b/include/hw/riscv/virt.h
index 6e5fbe5d3b..e6423258d3 100644
--- a/include/hw/riscv/virt.h
+++ b/include/hw/riscv/virt.h
@@ -37,6 +37,7 @@ enum {
     VIRT_DEBUG,
     VIRT_MROM,
     VIRT_TEST,
+    VIRT_RTC,
     VIRT_CLINT,
     VIRT_PLIC,
     VIRT_UART0,
@@ -49,6 +50,7 @@ enum {
 
 enum {
     UART0_IRQ = 10,
+    RTC_IRQ = 11,
     VIRTIO_IRQ = 1, /* 1 to 8 */
     VIRTIO_COUNT = 8,
     PCIE_IRQ = 0x20, /* 32 to 35 */
-- 
2.17.1



^ permalink raw reply related	[flat|nested] 11+ messages in thread

* Re: [PATCH v3 1/2] hw: timer: Add Goldfish RTC device
  2019-10-15  8:35 ` [PATCH v3 1/2] hw: timer: Add Goldfish RTC device Anup Patel
@ 2019-10-18 18:52   ` Palmer Dabbelt
  2019-10-18 20:59   ` Alistair Francis
  2019-10-18 21:15   ` Aleksandar Markovic
  2 siblings, 0 replies; 11+ messages in thread
From: Palmer Dabbelt @ 2019-10-18 18:52 UTC (permalink / raw)
  To: Anup Patel
  Cc: Peter Maydell, qemu-riscv, sagark, anup, Anup Patel, qemu-devel,
	Atish Patra, Alistair Francis, Bastian Koppelmann

On Tue, 15 Oct 2019 01:35:31 PDT (-0700), Anup Patel wrote:
> This patch adds model for Google Goldfish virtual platform RTC device.
>
> We will be adding Goldfish RTC device to the QEMU RISC-V virt machine
> for providing real date-time to Guest Linux. The corresponding Linux
> driver for Goldfish RTC device is already available in upstream Linux.
>
> For now, VM migration support is available but untested for Goldfish RTC
> device. It will be hardened in-future when we implement VM migration for
> KVM RISC-V.
>
> Signed-off-by: Anup Patel <anup.patel@wdc.com>
> ---
>  hw/rtc/Kconfig                  |   3 +
>  hw/rtc/Makefile.objs            |   1 +
>  hw/rtc/goldfish_rtc.c           | 278 ++++++++++++++++++++++++++++++++
>  include/hw/timer/goldfish_rtc.h |  46 ++++++
>  4 files changed, 328 insertions(+)
>  create mode 100644 hw/rtc/goldfish_rtc.c
>  create mode 100644 include/hw/timer/goldfish_rtc.h

I'd be happy to take a look at this, but I don't have a hw/rtc directory in my 
QEMU.  IIRC there was a refactoring going on here, is there a tree this is 
based on?

> diff --git a/hw/rtc/Kconfig b/hw/rtc/Kconfig
> index 45daa8d655..bafe6ac2c9 100644
> --- a/hw/rtc/Kconfig
> +++ b/hw/rtc/Kconfig
> @@ -21,3 +21,6 @@ config MC146818RTC
>  
>  config SUN4V_RTC
>      bool
> +
> +config GOLDFISH_RTC
> +    bool
> diff --git a/hw/rtc/Makefile.objs b/hw/rtc/Makefile.objs
> index 8dc9fcd3a9..aa208d0d10 100644
> --- a/hw/rtc/Makefile.objs
> +++ b/hw/rtc/Makefile.objs
> @@ -11,3 +11,4 @@ common-obj-$(CONFIG_EXYNOS4) += exynos4210_rtc.o
>  obj-$(CONFIG_MC146818RTC) += mc146818rtc.o
>  common-obj-$(CONFIG_SUN4V_RTC) += sun4v-rtc.o
>  common-obj-$(CONFIG_ASPEED_SOC) += aspeed_rtc.o
> +common-obj-$(CONFIG_GOLDFISH_RTC) += goldfish_rtc.o
> diff --git a/hw/rtc/goldfish_rtc.c b/hw/rtc/goldfish_rtc.c
> new file mode 100644
> index 0000000000..223616ed75
> --- /dev/null
> +++ b/hw/rtc/goldfish_rtc.c
> @@ -0,0 +1,278 @@
> +/*
> + * Goldfish virtual platform RTC
> + *
> + * Copyright (C) 2019 Western Digital Corporation or its affiliates.
> + *
> + * For more details on Google Goldfish virtual platform refer:
> + * https://android.googlesource.com/platform/external/qemu/+/master/docs/GOLDFISH-VIRTUAL-HARDWARE.TXT
> + *
> + * 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-common.h"
> +#include "hw/timer/goldfish_rtc.h"
> +#include "migration/vmstate.h"
> +#include "hw/irq.h"
> +#include "hw/qdev-properties.h"
> +#include "hw/sysbus.h"
> +#include "qemu/timer.h"
> +#include "sysemu/sysemu.h"
> +#include "qemu/cutils.h"
> +#include "qemu/log.h"
> +
> +#define RTC_TIME_LOW            0x00
> +#define RTC_TIME_HIGH           0x04
> +#define RTC_ALARM_LOW           0x08
> +#define RTC_ALARM_HIGH          0x0c
> +#define RTC_IRQ_ENABLED         0x10
> +#define RTC_CLEAR_ALARM         0x14
> +#define RTC_ALARM_STATUS        0x18
> +#define RTC_CLEAR_INTERRUPT     0x1c
> +
> +static void goldfish_rtc_update(GoldfishRTCState *s)
> +{
> +    qemu_set_irq(s->irq, (s->irq_pending & s->irq_enabled) ? 1 : 0);
> +}
> +
> +static void goldfish_rtc_interrupt(void *opaque)
> +{
> +    GoldfishRTCState *s = (GoldfishRTCState *)opaque;
> +
> +    s->alarm_running = 0;
> +    s->irq_pending = 1;
> +    goldfish_rtc_update(s);
> +}
> +
> +static uint64_t goldfish_rtc_get_count(GoldfishRTCState *s)
> +{
> +    return s->tick_offset + (uint64_t)qemu_clock_get_ns(rtc_clock);
> +}
> +
> +static void goldfish_rtc_clear_alarm(GoldfishRTCState *s)
> +{
> +    timer_del(s->timer);
> +    s->alarm_running = 0;
> +}
> +
> +static void goldfish_rtc_set_alarm(GoldfishRTCState *s)
> +{
> +    uint64_t ticks = goldfish_rtc_get_count(s);
> +    uint64_t event = s->alarm_next;
> +
> +    if (event <= ticks) {
> +        goldfish_rtc_clear_alarm(s);
> +        goldfish_rtc_interrupt(s);
> +    } else {
> +        int64_t now = qemu_clock_get_ns(rtc_clock);
> +        timer_mod(s->timer, now + (event - ticks));
> +        s->alarm_running = 1;
> +    }
> +}
> +
> +static uint64_t goldfish_rtc_read(void *opaque, hwaddr offset,
> +                                  unsigned size)
> +{
> +    GoldfishRTCState *s = (GoldfishRTCState *)opaque;
> +    uint64_t r;
> +
> +    switch (offset) {
> +    case RTC_TIME_LOW:
> +        r = goldfish_rtc_get_count(s) & 0xffffffff;
> +        break;
> +    case RTC_TIME_HIGH:
> +        r = goldfish_rtc_get_count(s) >> 32;
> +        break;
> +    case RTC_ALARM_LOW:
> +        r = s->alarm_next & 0xffffffff;
> +        break;
> +    case RTC_ALARM_HIGH:
> +        r = s->alarm_next >> 32;
> +        break;
> +    case RTC_IRQ_ENABLED:
> +        r = s->irq_enabled;
> +        break;
> +    case RTC_ALARM_STATUS:
> +        r = s->alarm_running;
> +        break;
> +    default:
> +        qemu_log_mask(LOG_GUEST_ERROR,
> +                      "goldfish_rtc_read: Bad offset 0x%x\n", (int)offset);
> +        r = 0;
> +        break;
> +    }
> +
> +    return r;
> +}
> +
> +static void goldfish_rtc_write(void *opaque, hwaddr offset,
> +                               uint64_t value, unsigned size)
> +{
> +    uint64_t current_tick, new_tick;
> +    GoldfishRTCState *s = (GoldfishRTCState *)opaque;
> +
> +    switch (offset) {
> +    case RTC_TIME_LOW:
> +        current_tick = goldfish_rtc_get_count(s);
> +        new_tick = current_tick & (0xffffffffULL << 32);
> +        new_tick |= value;
> +        s->tick_offset += new_tick - current_tick;
> +        break;
> +    case RTC_TIME_HIGH:
> +        current_tick = goldfish_rtc_get_count(s);
> +        new_tick = current_tick & 0xffffffffULL;
> +        new_tick |= (value << 32);
> +        s->tick_offset += new_tick - current_tick;
> +        break;
> +    case RTC_ALARM_LOW:
> +        s->alarm_next &= (0xffffffffULL << 32);
> +        s->alarm_next |= value;
> +        goldfish_rtc_set_alarm(s);
> +        break;
> +    case RTC_ALARM_HIGH:
> +        s->alarm_next &= 0xffffffffULL;
> +        s->alarm_next |= (value << 32);
> +        break;
> +    case RTC_IRQ_ENABLED:
> +        s->irq_enabled = (uint32_t)(value & 0x1);
> +        goldfish_rtc_update(s);
> +        break;
> +    case RTC_CLEAR_ALARM:
> +        goldfish_rtc_clear_alarm(s);
> +        break;
> +    case RTC_CLEAR_INTERRUPT:
> +        s->irq_pending = 0;
> +        goldfish_rtc_update(s);
> +        break;
> +    default:
> +        qemu_log_mask(LOG_GUEST_ERROR,
> +                      "goldfish_rtc_write: Bad offset 0x%x\n", (int)offset);
> +        break;
> +    }
> +}
> +
> +static int goldfish_rtc_pre_save(void *opaque)
> +{
> +    uint64_t delta;
> +    GoldfishRTCState *s = opaque;
> +
> +    /*
> +     * We want to migrate this offset, which sounds straightforward.
> +     * Unfortunately, we cannot directly pass tick_offset because
> +     * rtc_clock on destinetion Host might not be same source Host.
> +     *
> +     * To tackle, this we pass tick_offset relative to vm_clock from
> +     * source Host and make it relative to rtc_clock at destinetion Host.
> +     */
> +    delta = qemu_clock_get_ns(rtc_clock) -
> +            qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
> +    s->tick_offset_vmstate = s->tick_offset + delta;
> +
> +    return 0;
> +}
> +
> +static int goldfish_rtc_post_load(void *opaque, int version_id)
> +{
> +    uint64_t delta;
> +    GoldfishRTCState *s = opaque;
> +
> +    /*
> +     * We extract tick_offset from tick_offset_vmstate by doing
> +     * reverse math compared to pre_save() function.
> +     */
> +    delta = qemu_clock_get_ns(rtc_clock) -
> +            qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
> +    s->tick_offset = s->tick_offset_vmstate - delta;
> +
> +    return 0;
> +}
> +
> +static const MemoryRegionOps goldfish_rtc_ops = {
> +    .read = goldfish_rtc_read,
> +    .write = goldfish_rtc_write,
> +    .endianness = DEVICE_LITTLE_ENDIAN,
> +    .valid = {
> +        .min_access_size = 4,
> +        .max_access_size = 4
> +    }
> +};
> +
> +static const VMStateDescription goldfish_rtc_vmstate = {
> +    .name = TYPE_GOLDFISH_RTC,
> +    .version_id = 1,
> +    .pre_save = goldfish_rtc_pre_save,
> +    .post_load = goldfish_rtc_post_load,
> +    .fields = (VMStateField[]) {
> +        VMSTATE_UINT64(tick_offset_vmstate, GoldfishRTCState),
> +        VMSTATE_UINT64(alarm_next, GoldfishRTCState),
> +        VMSTATE_UINT32(alarm_running, GoldfishRTCState),
> +        VMSTATE_UINT32(irq_pending, GoldfishRTCState),
> +        VMSTATE_UINT32(irq_enabled, GoldfishRTCState),
> +        VMSTATE_END_OF_LIST()
> +    }
> +};
> +
> +static void goldfish_rtc_reset(DeviceState *dev)
> +{
> +    GoldfishRTCState *s = GOLDFISH_RTC(dev);
> +    struct tm tm;
> +
> +    timer_del(s->timer);
> +
> +    qemu_get_timedate(&tm, 0);
> +    s->tick_offset = mktimegm(&tm);
> +    s->tick_offset *= NANOSECONDS_PER_SECOND;
> +    s->tick_offset -= qemu_clock_get_ns(rtc_clock);
> +    s->tick_offset_vmstate = 0;
> +    s->alarm_next = 0;
> +    s->alarm_running = 0;
> +    s->irq_pending = 0;
> +    s->irq_enabled = 0;
> +}
> +
> +static void goldfish_rtc_realize(DeviceState *d, Error **errp)
> +{
> +    SysBusDevice *dev = SYS_BUS_DEVICE(d);
> +    GoldfishRTCState *s = GOLDFISH_RTC(d);
> +
> +    memory_region_init_io(&s->iomem, OBJECT(s), &goldfish_rtc_ops, s,
> +                          "goldfish_rtc", 0x1000);
> +    sysbus_init_mmio(dev, &s->iomem);
> +
> +    sysbus_init_irq(dev, &s->irq);
> +
> +    s->timer = timer_new_ns(rtc_clock, goldfish_rtc_interrupt, s);
> +}
> +
> +static void goldfish_rtc_class_init(ObjectClass *klass, void *data)
> +{
> +    DeviceClass *dc = DEVICE_CLASS(klass);
> +
> +    dc->realize = goldfish_rtc_realize;
> +    dc->reset = goldfish_rtc_reset;
> +    dc->vmsd = &goldfish_rtc_vmstate;
> +}
> +
> +static const TypeInfo goldfish_rtc_info = {
> +    .name          = TYPE_GOLDFISH_RTC,
> +    .parent        = TYPE_SYS_BUS_DEVICE,
> +    .instance_size = sizeof(GoldfishRTCState),
> +    .class_init    = goldfish_rtc_class_init,
> +};
> +
> +static void goldfish_rtc_register_types(void)
> +{
> +    type_register_static(&goldfish_rtc_info);
> +}
> +
> +type_init(goldfish_rtc_register_types)
> diff --git a/include/hw/timer/goldfish_rtc.h b/include/hw/timer/goldfish_rtc.h
> new file mode 100644
> index 0000000000..dfb6d70b86
> --- /dev/null
> +++ b/include/hw/timer/goldfish_rtc.h
> @@ -0,0 +1,46 @@
> +/*
> + * Goldfish virtual platform RTC
> + *
> + * Copyright (C) 2019 Western Digital Corporation or its affiliates.
> + *
> + * For more details on Google Goldfish virtual platform refer:
> + * https://android.googlesource.com/platform/external/qemu/+/master/docs/GOLDFISH-VIRTUAL-HARDWARE.TXT
> + *
> + * 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/>.
> + */
> +
> +#ifndef HW_TIMER_GOLDFISH_RTC_H
> +#define HW_TIMER_GOLDFISH_RTC_H
> +
> +#include "hw/sysbus.h"
> +
> +#define TYPE_GOLDFISH_RTC "goldfish_rtc"
> +#define GOLDFISH_RTC(obj) \
> +OBJECT_CHECK(GoldfishRTCState, (obj), TYPE_GOLDFISH_RTC)
> +
> +typedef struct GoldfishRTCState {
> +    SysBusDevice parent_obj;
> +
> +    MemoryRegion iomem;
> +    QEMUTimer *timer;
> +    qemu_irq irq;
> +
> +    uint64_t tick_offset;
> +    uint64_t tick_offset_vmstate;
> +    uint64_t alarm_next;
> +    uint32_t alarm_running;
> +    uint32_t irq_pending;
> +    uint32_t irq_enabled;
> +} GoldfishRTCState;
> +
> +#endif
> -- 
> 2.17.1


^ permalink raw reply	[flat|nested] 11+ messages in thread

* Re: [PATCH v3 2/2] riscv: virt: Use Goldfish RTC device
  2019-10-15  8:35 ` [PATCH v3 2/2] riscv: virt: Use " Anup Patel
@ 2019-10-18 18:52   ` Palmer Dabbelt
  2019-10-18 21:00   ` Alistair Francis
  1 sibling, 0 replies; 11+ messages in thread
From: Palmer Dabbelt @ 2019-10-18 18:52 UTC (permalink / raw)
  To: Anup Patel
  Cc: Peter Maydell, qemu-riscv, sagark, anup, Anup Patel, qemu-devel,
	Atish Patra, Alistair Francis, Bastian Koppelmann

On Tue, 15 Oct 2019 01:35:42 PDT (-0700), Anup Patel wrote:
> We extend QEMU RISC-V virt machine by adding Goldfish RTC device
> to it. This will allow Guest Linux to sync it's local date/time
> with Host date/time via RTC device.
>
> Signed-off-by: Anup Patel <anup.patel@wdc.com>
> ---
>  hw/riscv/Kconfig        |  1 +
>  hw/riscv/virt.c         | 15 +++++++++++++++
>  include/hw/riscv/virt.h |  2 ++
>  3 files changed, 18 insertions(+)
>
> diff --git a/hw/riscv/Kconfig b/hw/riscv/Kconfig
> index fb19b2df3a..b33753c780 100644
> --- a/hw/riscv/Kconfig
> +++ b/hw/riscv/Kconfig
> @@ -34,6 +34,7 @@ config RISCV_VIRT
>      select PCI
>      select HART
>      select SERIAL
> +    select GOLDFISH_RTC
>      select VIRTIO_MMIO
>      select PCI_EXPRESS_GENERIC_BRIDGE
>      select SIFIVE
> diff --git a/hw/riscv/virt.c b/hw/riscv/virt.c
> index d36f5625ec..95c42ab993 100644
> --- a/hw/riscv/virt.c
> +++ b/hw/riscv/virt.c
> @@ -57,6 +57,7 @@ static const struct MemmapEntry {
>      [VIRT_DEBUG] =       {        0x0,         0x100 },
>      [VIRT_MROM] =        {     0x1000,       0x11000 },
>      [VIRT_TEST] =        {   0x100000,        0x1000 },
> +    [VIRT_RTC] =         {   0x101000,        0x1000 },
>      [VIRT_CLINT] =       {  0x2000000,       0x10000 },
>      [VIRT_PLIC] =        {  0xc000000,     0x4000000 },
>      [VIRT_UART0] =       { 0x10000000,         0x100 },
> @@ -310,6 +311,17 @@ static void create_fdt(RISCVVirtState *s, const struct MemmapEntry *memmap,
>      qemu_fdt_setprop_cell(fdt, nodename, "interrupt-parent", plic_phandle);
>      qemu_fdt_setprop_cell(fdt, nodename, "interrupts", UART0_IRQ);
>  
> +    nodename = g_strdup_printf("/rtc@%lx",
> +        (long)memmap[VIRT_RTC].base);
> +    qemu_fdt_add_subnode(fdt, nodename);
> +    qemu_fdt_setprop_string(fdt, nodename, "compatible",
> +        "google,goldfish-rtc");
> +    qemu_fdt_setprop_cells(fdt, nodename, "reg",
> +        0x0, memmap[VIRT_RTC].base,
> +        0x0, memmap[VIRT_RTC].size);
> +    qemu_fdt_setprop_cell(fdt, nodename, "interrupt-parent", plic_phandle);
> +    qemu_fdt_setprop_cell(fdt, nodename, "interrupts", RTC_IRQ);
> +
>      qemu_fdt_add_subnode(fdt, "/chosen");
>      qemu_fdt_setprop_string(fdt, "/chosen", "stdout-path", nodename);
>      if (cmdline) {
> @@ -496,6 +508,9 @@ static void riscv_virt_board_init(MachineState *machine)
>          0, qdev_get_gpio_in(DEVICE(s->plic), UART0_IRQ), 399193,
>          serial_hd(0), DEVICE_LITTLE_ENDIAN);
>  
> +    sysbus_create_simple("goldfish_rtc", memmap[VIRT_RTC].base,
> +        qdev_get_gpio_in(DEVICE(s->plic), RTC_IRQ));
> +
>      g_free(plic_hart_config);
>  }
>  
> diff --git a/include/hw/riscv/virt.h b/include/hw/riscv/virt.h
> index 6e5fbe5d3b..e6423258d3 100644
> --- a/include/hw/riscv/virt.h
> +++ b/include/hw/riscv/virt.h
> @@ -37,6 +37,7 @@ enum {
>      VIRT_DEBUG,
>      VIRT_MROM,
>      VIRT_TEST,
> +    VIRT_RTC,
>      VIRT_CLINT,
>      VIRT_PLIC,
>      VIRT_UART0,
> @@ -49,6 +50,7 @@ enum {
>  
>  enum {
>      UART0_IRQ = 10,
> +    RTC_IRQ = 11,
>      VIRTIO_IRQ = 1, /* 1 to 8 */
>      VIRTIO_COUNT = 8,
>      PCIE_IRQ = 0x20, /* 32 to 35 */

This is a wacky enum, but it's already there.  I'm going to assume this patch 
will get merged and then fix it later.

> -- 
> 2.17.1

Reviewed-by: Palmer Dabbelt <palmer@sifive.com>
Acked-by: Palmer Dabbelt <palmer@sifive.com>

I think it's easier to just keep this with the goldfish implementation.  I'm 
assuming that will go in through a different tree, as per my comments on that 
patch.


^ permalink raw reply	[flat|nested] 11+ messages in thread

* Re: [PATCH v3 1/2] hw: timer: Add Goldfish RTC device
  2019-10-15  8:35 ` [PATCH v3 1/2] hw: timer: Add Goldfish RTC device Anup Patel
  2019-10-18 18:52   ` Palmer Dabbelt
@ 2019-10-18 20:59   ` Alistair Francis
  2019-10-19  4:21     ` Anup Patel
  2019-10-18 21:15   ` Aleksandar Markovic
  2 siblings, 1 reply; 11+ messages in thread
From: Alistair Francis @ 2019-10-18 20:59 UTC (permalink / raw)
  To: Anup Patel
  Cc: Peter Maydell, qemu-riscv@nongnu.org, Sagar Karandikar,
	Bastian Koppelmann, Palmer Dabbelt, qemu-devel@nongnu.org,
	Atish Patra, Alistair Francis, Anup Patel

On Tue, Oct 15, 2019 at 1:36 AM Anup Patel <Anup.Patel@wdc.com> wrote:
>
> This patch adds model for Google Goldfish virtual platform RTC device.
>
> We will be adding Goldfish RTC device to the QEMU RISC-V virt machine
> for providing real date-time to Guest Linux. The corresponding Linux
> driver for Goldfish RTC device is already available in upstream Linux.
>
> For now, VM migration support is available but untested for Goldfish RTC
> device. It will be hardened in-future when we implement VM migration for
> KVM RISC-V.
>
> Signed-off-by: Anup Patel <anup.patel@wdc.com>
> ---
>  hw/rtc/Kconfig                  |   3 +
>  hw/rtc/Makefile.objs            |   1 +
>  hw/rtc/goldfish_rtc.c           | 278 ++++++++++++++++++++++++++++++++
>  include/hw/timer/goldfish_rtc.h |  46 ++++++
>  4 files changed, 328 insertions(+)
>  create mode 100644 hw/rtc/goldfish_rtc.c
>  create mode 100644 include/hw/timer/goldfish_rtc.h
>
> diff --git a/hw/rtc/Kconfig b/hw/rtc/Kconfig
> index 45daa8d655..bafe6ac2c9 100644
> --- a/hw/rtc/Kconfig
> +++ b/hw/rtc/Kconfig
> @@ -21,3 +21,6 @@ config MC146818RTC
>
>  config SUN4V_RTC
>      bool
> +
> +config GOLDFISH_RTC
> +    bool
> diff --git a/hw/rtc/Makefile.objs b/hw/rtc/Makefile.objs
> index 8dc9fcd3a9..aa208d0d10 100644
> --- a/hw/rtc/Makefile.objs
> +++ b/hw/rtc/Makefile.objs
> @@ -11,3 +11,4 @@ common-obj-$(CONFIG_EXYNOS4) += exynos4210_rtc.o
>  obj-$(CONFIG_MC146818RTC) += mc146818rtc.o
>  common-obj-$(CONFIG_SUN4V_RTC) += sun4v-rtc.o
>  common-obj-$(CONFIG_ASPEED_SOC) += aspeed_rtc.o
> +common-obj-$(CONFIG_GOLDFISH_RTC) += goldfish_rtc.o
> diff --git a/hw/rtc/goldfish_rtc.c b/hw/rtc/goldfish_rtc.c
> new file mode 100644
> index 0000000000..223616ed75
> --- /dev/null
> +++ b/hw/rtc/goldfish_rtc.c
> @@ -0,0 +1,278 @@
> +/*
> + * Goldfish virtual platform RTC
> + *
> + * Copyright (C) 2019 Western Digital Corporation or its affiliates.
> + *
> + * For more details on Google Goldfish virtual platform refer:
> + * https://android.googlesource.com/platform/external/qemu/+/master/docs/GOLDFISH-VIRTUAL-HARDWARE.TXT
> + *
> + * 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-common.h"
> +#include "hw/timer/goldfish_rtc.h"
> +#include "migration/vmstate.h"
> +#include "hw/irq.h"
> +#include "hw/qdev-properties.h"
> +#include "hw/sysbus.h"
> +#include "qemu/timer.h"
> +#include "sysemu/sysemu.h"
> +#include "qemu/cutils.h"
> +#include "qemu/log.h"
> +
> +#define RTC_TIME_LOW            0x00
> +#define RTC_TIME_HIGH           0x04
> +#define RTC_ALARM_LOW           0x08
> +#define RTC_ALARM_HIGH          0x0c
> +#define RTC_IRQ_ENABLED         0x10
> +#define RTC_CLEAR_ALARM         0x14
> +#define RTC_ALARM_STATUS        0x18
> +#define RTC_CLEAR_INTERRUPT     0x1c
> +
> +static void goldfish_rtc_update(GoldfishRTCState *s)
> +{
> +    qemu_set_irq(s->irq, (s->irq_pending & s->irq_enabled) ? 1 : 0);
> +}
> +
> +static void goldfish_rtc_interrupt(void *opaque)
> +{
> +    GoldfishRTCState *s = (GoldfishRTCState *)opaque;
> +
> +    s->alarm_running = 0;
> +    s->irq_pending = 1;
> +    goldfish_rtc_update(s);
> +}
> +
> +static uint64_t goldfish_rtc_get_count(GoldfishRTCState *s)
> +{
> +    return s->tick_offset + (uint64_t)qemu_clock_get_ns(rtc_clock);
> +}
> +
> +static void goldfish_rtc_clear_alarm(GoldfishRTCState *s)
> +{
> +    timer_del(s->timer);
> +    s->alarm_running = 0;
> +}
> +
> +static void goldfish_rtc_set_alarm(GoldfishRTCState *s)
> +{
> +    uint64_t ticks = goldfish_rtc_get_count(s);
> +    uint64_t event = s->alarm_next;
> +
> +    if (event <= ticks) {
> +        goldfish_rtc_clear_alarm(s);
> +        goldfish_rtc_interrupt(s);
> +    } else {
> +        int64_t now = qemu_clock_get_ns(rtc_clock);
> +        timer_mod(s->timer, now + (event - ticks));

Isn't this just: event - s->tick_offset?

> +        s->alarm_running = 1;
> +    }
> +}
> +
> +static uint64_t goldfish_rtc_read(void *opaque, hwaddr offset,
> +                                  unsigned size)
> +{
> +    GoldfishRTCState *s = (GoldfishRTCState *)opaque;
> +    uint64_t r;

There should be a trace or debug print showing read/write operations.

> +
> +    switch (offset) {
> +    case RTC_TIME_LOW:
> +        r = goldfish_rtc_get_count(s) & 0xffffffff;
> +        break;
> +    case RTC_TIME_HIGH:
> +        r = goldfish_rtc_get_count(s) >> 32;
> +        break;
> +    case RTC_ALARM_LOW:
> +        r = s->alarm_next & 0xffffffff;
> +        break;
> +    case RTC_ALARM_HIGH:
> +        r = s->alarm_next >> 32;
> +        break;
> +    case RTC_IRQ_ENABLED:
> +        r = s->irq_enabled;
> +        break;
> +    case RTC_ALARM_STATUS:
> +        r = s->alarm_running;
> +        break;
> +    default:
> +        qemu_log_mask(LOG_GUEST_ERROR,
> +                      "goldfish_rtc_read: Bad offset 0x%x\n", (int)offset);
> +        r = 0;

Just set 0 as the init value and remove this.

> +        break;
> +    }
> +
> +    return r;
> +}
> +
> +static void goldfish_rtc_write(void *opaque, hwaddr offset,
> +                               uint64_t value, unsigned size)
> +{
> +    uint64_t current_tick, new_tick;
> +    GoldfishRTCState *s = (GoldfishRTCState *)opaque;

The state struct should be first.

> +
> +    switch (offset) {
> +    case RTC_TIME_LOW:
> +        current_tick = goldfish_rtc_get_count(s);
> +        new_tick = current_tick & (0xffffffffULL << 32);
> +        new_tick |= value;
> +        s->tick_offset += new_tick - current_tick;
> +        break;
> +    case RTC_TIME_HIGH:
> +        current_tick = goldfish_rtc_get_count(s);
> +        new_tick = current_tick & 0xffffffffULL;
> +        new_tick |= (value << 32);
> +        s->tick_offset += new_tick - current_tick;
> +        break;
> +    case RTC_ALARM_LOW:
> +        s->alarm_next &= (0xffffffffULL << 32);
> +        s->alarm_next |= value;
> +        goldfish_rtc_set_alarm(s);
> +        break;
> +    case RTC_ALARM_HIGH:
> +        s->alarm_next &= 0xffffffffULL;
> +        s->alarm_next |= (value << 32);
> +        break;
> +    case RTC_IRQ_ENABLED:
> +        s->irq_enabled = (uint32_t)(value & 0x1);
> +        goldfish_rtc_update(s);
> +        break;
> +    case RTC_CLEAR_ALARM:
> +        goldfish_rtc_clear_alarm(s);
> +        break;
> +    case RTC_CLEAR_INTERRUPT:
> +        s->irq_pending = 0;
> +        goldfish_rtc_update(s);
> +        break;
> +    default:
> +        qemu_log_mask(LOG_GUEST_ERROR,
> +                      "goldfish_rtc_write: Bad offset 0x%x\n", (int)offset);
> +        break;
> +    }
> +}
> +
> +static int goldfish_rtc_pre_save(void *opaque)
> +{
> +    uint64_t delta;
> +    GoldfishRTCState *s = opaque;
> +
> +    /*
> +     * We want to migrate this offset, which sounds straightforward.
> +     * Unfortunately, we cannot directly pass tick_offset because
> +     * rtc_clock on destinetion Host might not be same source Host.

s/destinetion/destination/g

and below as well.

Alistair

> +     *
> +     * To tackle, this we pass tick_offset relative to vm_clock from
> +     * source Host and make it relative to rtc_clock at destinetion Host.
> +     */
> +    delta = qemu_clock_get_ns(rtc_clock) -
> +            qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
> +    s->tick_offset_vmstate = s->tick_offset + delta;
> +
> +    return 0;
> +}
> +
> +static int goldfish_rtc_post_load(void *opaque, int version_id)
> +{
> +    uint64_t delta;
> +    GoldfishRTCState *s = opaque;
> +
> +    /*
> +     * We extract tick_offset from tick_offset_vmstate by doing
> +     * reverse math compared to pre_save() function.
> +     */
> +    delta = qemu_clock_get_ns(rtc_clock) -
> +            qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
> +    s->tick_offset = s->tick_offset_vmstate - delta;
> +
> +    return 0;
> +}
> +
> +static const MemoryRegionOps goldfish_rtc_ops = {
> +    .read = goldfish_rtc_read,
> +    .write = goldfish_rtc_write,
> +    .endianness = DEVICE_LITTLE_ENDIAN,
> +    .valid = {
> +        .min_access_size = 4,
> +        .max_access_size = 4
> +    }
> +};
> +
> +static const VMStateDescription goldfish_rtc_vmstate = {
> +    .name = TYPE_GOLDFISH_RTC,
> +    .version_id = 1,
> +    .pre_save = goldfish_rtc_pre_save,
> +    .post_load = goldfish_rtc_post_load,
> +    .fields = (VMStateField[]) {
> +        VMSTATE_UINT64(tick_offset_vmstate, GoldfishRTCState),
> +        VMSTATE_UINT64(alarm_next, GoldfishRTCState),
> +        VMSTATE_UINT32(alarm_running, GoldfishRTCState),
> +        VMSTATE_UINT32(irq_pending, GoldfishRTCState),
> +        VMSTATE_UINT32(irq_enabled, GoldfishRTCState),
> +        VMSTATE_END_OF_LIST()
> +    }
> +};
> +
> +static void goldfish_rtc_reset(DeviceState *dev)
> +{
> +    GoldfishRTCState *s = GOLDFISH_RTC(dev);
> +    struct tm tm;
> +
> +    timer_del(s->timer);
> +
> +    qemu_get_timedate(&tm, 0);
> +    s->tick_offset = mktimegm(&tm);
> +    s->tick_offset *= NANOSECONDS_PER_SECOND;
> +    s->tick_offset -= qemu_clock_get_ns(rtc_clock);
> +    s->tick_offset_vmstate = 0;
> +    s->alarm_next = 0;
> +    s->alarm_running = 0;
> +    s->irq_pending = 0;
> +    s->irq_enabled = 0;
> +}
> +
> +static void goldfish_rtc_realize(DeviceState *d, Error **errp)
> +{
> +    SysBusDevice *dev = SYS_BUS_DEVICE(d);
> +    GoldfishRTCState *s = GOLDFISH_RTC(d);
> +
> +    memory_region_init_io(&s->iomem, OBJECT(s), &goldfish_rtc_ops, s,
> +                          "goldfish_rtc", 0x1000);
> +    sysbus_init_mmio(dev, &s->iomem);
> +
> +    sysbus_init_irq(dev, &s->irq);
> +
> +    s->timer = timer_new_ns(rtc_clock, goldfish_rtc_interrupt, s);
> +}
> +
> +static void goldfish_rtc_class_init(ObjectClass *klass, void *data)
> +{
> +    DeviceClass *dc = DEVICE_CLASS(klass);
> +
> +    dc->realize = goldfish_rtc_realize;
> +    dc->reset = goldfish_rtc_reset;
> +    dc->vmsd = &goldfish_rtc_vmstate;
> +}
> +
> +static const TypeInfo goldfish_rtc_info = {
> +    .name          = TYPE_GOLDFISH_RTC,
> +    .parent        = TYPE_SYS_BUS_DEVICE,
> +    .instance_size = sizeof(GoldfishRTCState),
> +    .class_init    = goldfish_rtc_class_init,
> +};
> +
> +static void goldfish_rtc_register_types(void)
> +{
> +    type_register_static(&goldfish_rtc_info);
> +}
> +
> +type_init(goldfish_rtc_register_types)
> diff --git a/include/hw/timer/goldfish_rtc.h b/include/hw/timer/goldfish_rtc.h
> new file mode 100644
> index 0000000000..dfb6d70b86
> --- /dev/null
> +++ b/include/hw/timer/goldfish_rtc.h
> @@ -0,0 +1,46 @@
> +/*
> + * Goldfish virtual platform RTC
> + *
> + * Copyright (C) 2019 Western Digital Corporation or its affiliates.
> + *
> + * For more details on Google Goldfish virtual platform refer:
> + * https://android.googlesource.com/platform/external/qemu/+/master/docs/GOLDFISH-VIRTUAL-HARDWARE.TXT
> + *
> + * 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/>.
> + */
> +
> +#ifndef HW_TIMER_GOLDFISH_RTC_H
> +#define HW_TIMER_GOLDFISH_RTC_H
> +
> +#include "hw/sysbus.h"
> +
> +#define TYPE_GOLDFISH_RTC "goldfish_rtc"
> +#define GOLDFISH_RTC(obj) \
> +OBJECT_CHECK(GoldfishRTCState, (obj), TYPE_GOLDFISH_RTC)
> +
> +typedef struct GoldfishRTCState {
> +    SysBusDevice parent_obj;
> +
> +    MemoryRegion iomem;
> +    QEMUTimer *timer;
> +    qemu_irq irq;
> +
> +    uint64_t tick_offset;
> +    uint64_t tick_offset_vmstate;
> +    uint64_t alarm_next;
> +    uint32_t alarm_running;
> +    uint32_t irq_pending;
> +    uint32_t irq_enabled;
> +} GoldfishRTCState;
> +
> +#endif
> --
> 2.17.1
>
>


^ permalink raw reply	[flat|nested] 11+ messages in thread

* Re: [PATCH v3 2/2] riscv: virt: Use Goldfish RTC device
  2019-10-15  8:35 ` [PATCH v3 2/2] riscv: virt: Use " Anup Patel
  2019-10-18 18:52   ` Palmer Dabbelt
@ 2019-10-18 21:00   ` Alistair Francis
  1 sibling, 0 replies; 11+ messages in thread
From: Alistair Francis @ 2019-10-18 21:00 UTC (permalink / raw)
  To: Anup Patel
  Cc: Peter Maydell, qemu-riscv@nongnu.org, Sagar Karandikar,
	Bastian Koppelmann, Palmer Dabbelt, qemu-devel@nongnu.org,
	Atish Patra, Alistair Francis, Anup Patel

On Tue, Oct 15, 2019 at 1:37 AM Anup Patel <Anup.Patel@wdc.com> wrote:
>
> We extend QEMU RISC-V virt machine by adding Goldfish RTC device
> to it. This will allow Guest Linux to sync it's local date/time
> with Host date/time via RTC device.
>
> Signed-off-by: Anup Patel <anup.patel@wdc.com>

Reviewed-by: Alistair Francis <alistair.francis@wdc.com>

Alistair

> ---
>  hw/riscv/Kconfig        |  1 +
>  hw/riscv/virt.c         | 15 +++++++++++++++
>  include/hw/riscv/virt.h |  2 ++
>  3 files changed, 18 insertions(+)
>
> diff --git a/hw/riscv/Kconfig b/hw/riscv/Kconfig
> index fb19b2df3a..b33753c780 100644
> --- a/hw/riscv/Kconfig
> +++ b/hw/riscv/Kconfig
> @@ -34,6 +34,7 @@ config RISCV_VIRT
>      select PCI
>      select HART
>      select SERIAL
> +    select GOLDFISH_RTC
>      select VIRTIO_MMIO
>      select PCI_EXPRESS_GENERIC_BRIDGE
>      select SIFIVE
> diff --git a/hw/riscv/virt.c b/hw/riscv/virt.c
> index d36f5625ec..95c42ab993 100644
> --- a/hw/riscv/virt.c
> +++ b/hw/riscv/virt.c
> @@ -57,6 +57,7 @@ static const struct MemmapEntry {
>      [VIRT_DEBUG] =       {        0x0,         0x100 },
>      [VIRT_MROM] =        {     0x1000,       0x11000 },
>      [VIRT_TEST] =        {   0x100000,        0x1000 },
> +    [VIRT_RTC] =         {   0x101000,        0x1000 },
>      [VIRT_CLINT] =       {  0x2000000,       0x10000 },
>      [VIRT_PLIC] =        {  0xc000000,     0x4000000 },
>      [VIRT_UART0] =       { 0x10000000,         0x100 },
> @@ -310,6 +311,17 @@ static void create_fdt(RISCVVirtState *s, const struct MemmapEntry *memmap,
>      qemu_fdt_setprop_cell(fdt, nodename, "interrupt-parent", plic_phandle);
>      qemu_fdt_setprop_cell(fdt, nodename, "interrupts", UART0_IRQ);
>
> +    nodename = g_strdup_printf("/rtc@%lx",
> +        (long)memmap[VIRT_RTC].base);
> +    qemu_fdt_add_subnode(fdt, nodename);
> +    qemu_fdt_setprop_string(fdt, nodename, "compatible",
> +        "google,goldfish-rtc");
> +    qemu_fdt_setprop_cells(fdt, nodename, "reg",
> +        0x0, memmap[VIRT_RTC].base,
> +        0x0, memmap[VIRT_RTC].size);
> +    qemu_fdt_setprop_cell(fdt, nodename, "interrupt-parent", plic_phandle);
> +    qemu_fdt_setprop_cell(fdt, nodename, "interrupts", RTC_IRQ);
> +
>      qemu_fdt_add_subnode(fdt, "/chosen");
>      qemu_fdt_setprop_string(fdt, "/chosen", "stdout-path", nodename);
>      if (cmdline) {
> @@ -496,6 +508,9 @@ static void riscv_virt_board_init(MachineState *machine)
>          0, qdev_get_gpio_in(DEVICE(s->plic), UART0_IRQ), 399193,
>          serial_hd(0), DEVICE_LITTLE_ENDIAN);
>
> +    sysbus_create_simple("goldfish_rtc", memmap[VIRT_RTC].base,
> +        qdev_get_gpio_in(DEVICE(s->plic), RTC_IRQ));
> +
>      g_free(plic_hart_config);
>  }
>
> diff --git a/include/hw/riscv/virt.h b/include/hw/riscv/virt.h
> index 6e5fbe5d3b..e6423258d3 100644
> --- a/include/hw/riscv/virt.h
> +++ b/include/hw/riscv/virt.h
> @@ -37,6 +37,7 @@ enum {
>      VIRT_DEBUG,
>      VIRT_MROM,
>      VIRT_TEST,
> +    VIRT_RTC,
>      VIRT_CLINT,
>      VIRT_PLIC,
>      VIRT_UART0,
> @@ -49,6 +50,7 @@ enum {
>
>  enum {
>      UART0_IRQ = 10,
> +    RTC_IRQ = 11,
>      VIRTIO_IRQ = 1, /* 1 to 8 */
>      VIRTIO_COUNT = 8,
>      PCIE_IRQ = 0x20, /* 32 to 35 */
> --
> 2.17.1
>
>


^ permalink raw reply	[flat|nested] 11+ messages in thread

* Re: [PATCH v3 1/2] hw: timer: Add Goldfish RTC device
  2019-10-15  8:35 ` [PATCH v3 1/2] hw: timer: Add Goldfish RTC device Anup Patel
  2019-10-18 18:52   ` Palmer Dabbelt
  2019-10-18 20:59   ` Alistair Francis
@ 2019-10-18 21:15   ` Aleksandar Markovic
  2019-10-19  4:33     ` Anup Patel
  2 siblings, 1 reply; 11+ messages in thread
From: Aleksandar Markovic @ 2019-10-18 21:15 UTC (permalink / raw)
  To: Anup Patel
  Cc: Peter Maydell, qemu-riscv@nongnu.org, Sagar Karandikar,
	Bastian Koppelmann, Palmer Dabbelt, qemu-devel@nongnu.org,
	Atish Patra, Alistair Francis, Anup Patel

[-- Attachment #1: Type: text/plain, Size: 13060 bytes --]

ū

On Tuesday, October 15, 2019, Anup Patel <Anup.Patel@wdc.com> wrote:

> This patch adds model for Google Goldfish virtual platform RTC device.
>
> We will be adding Goldfish RTC device to the QEMU RISC-V virt machine
> for providing real date-time to Guest Linux. The corresponding Linux
> driver for Goldfish RTC device is already available in upstream Linux.
>
> For now, VM migration support is available but untested for Goldfish RTC
> device. It will be hardened in-future when we implement VM migration for
> KVM RISC-V.
>
> Signed-off-by: Anup Patel <anup.patel@wdc.com>
> ---
>  hw/rtc/Kconfig                  |   3 +
>  hw/rtc/Makefile.objs            |   1 +
>  hw/rtc/goldfish_rtc.c           | 278 ++++++++++++++++++++++++++++++++
>  include/hw/timer/goldfish_rtc.h |  46 ++++++
>  4 files changed, 328 insertions(+)
>  create mode 100644 hw/rtc/goldfish_rtc.c
>  create mode 100644 include/hw/timer/goldfish_rtc.h
>
>
Do you plan to add some other devices from Goldfish platform?

Did you base your code on Android emulator code?

Related to the previous question, are you sure the copyright line should go
to Western Digital only?

Thanks, A.




> diff --git a/hw/rtc/Kconfig b/hw/rtc/Kconfig
> index 45daa8d655..bafe6ac2c9 100644
> --- a/hw/rtc/Kconfig
> +++ b/hw/rtc/Kconfig
> @@ -21,3 +21,6 @@ config MC146818RTC
>
>  config SUN4V_RTC
>      bool
> +
> +config GOLDFISH_RTC
> +    bool
> diff --git a/hw/rtc/Makefile.objs b/hw/rtc/Makefile.objs
> index 8dc9fcd3a9..aa208d0d10 100644
> --- a/hw/rtc/Makefile.objs
> +++ b/hw/rtc/Makefile.objs
> @@ -11,3 +11,4 @@ common-obj-$(CONFIG_EXYNOS4) += exynos4210_rtc.o
>  obj-$(CONFIG_MC146818RTC) += mc146818rtc.o
>  common-obj-$(CONFIG_SUN4V_RTC) += sun4v-rtc.o
>  common-obj-$(CONFIG_ASPEED_SOC) += aspeed_rtc.o
> +common-obj-$(CONFIG_GOLDFISH_RTC) += goldfish_rtc.o
> diff --git a/hw/rtc/goldfish_rtc.c b/hw/rtc/goldfish_rtc.c
> new file mode 100644
> index 0000000000..223616ed75
> --- /dev/null
> +++ b/hw/rtc/goldfish_rtc.c
> @@ -0,0 +1,278 @@
> +/*
> + * Goldfish virtual platform RTC
> + *
> + * Copyright (C) 2019 Western Digital Corporation or its affiliates.
> + *
> + * For more details on Google Goldfish virtual platform refer:
> + * https://android.googlesource.com/platform/external/qemu/+/
> master/docs/GOLDFISH-VIRTUAL-HARDWARE.TXT
> + *
> + * 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-common.h"
> +#include "hw/timer/goldfish_rtc.h"
> +#include "migration/vmstate.h"
> +#include "hw/irq.h"
> +#include "hw/qdev-properties.h"
> +#include "hw/sysbus.h"
> +#include "qemu/timer.h"
> +#include "sysemu/sysemu.h"
> +#include "qemu/cutils.h"
> +#include "qemu/log.h"
> +
> +#define RTC_TIME_LOW            0x00
> +#define RTC_TIME_HIGH           0x04
> +#define RTC_ALARM_LOW           0x08
> +#define RTC_ALARM_HIGH          0x0c
> +#define RTC_IRQ_ENABLED         0x10
> +#define RTC_CLEAR_ALARM         0x14
> +#define RTC_ALARM_STATUS        0x18
> +#define RTC_CLEAR_INTERRUPT     0x1c
> +
> +static void goldfish_rtc_update(GoldfishRTCState *s)
> +{
> +    qemu_set_irq(s->irq, (s->irq_pending & s->irq_enabled) ? 1 : 0);
> +}
> +
> +static void goldfish_rtc_interrupt(void *opaque)
> +{
> +    GoldfishRTCState *s = (GoldfishRTCState *)opaque;
> +
> +    s->alarm_running = 0;
> +    s->irq_pending = 1;
> +    goldfish_rtc_update(s);
> +}
> +
> +static uint64_t goldfish_rtc_get_count(GoldfishRTCState *s)
> +{
> +    return s->tick_offset + (uint64_t)qemu_clock_get_ns(rtc_clock);
> +}
> +
> +static void goldfish_rtc_clear_alarm(GoldfishRTCState *s)
> +{
> +    timer_del(s->timer);
> +    s->alarm_running = 0;
> +}
> +
> +static void goldfish_rtc_set_alarm(GoldfishRTCState *s)
> +{
> +    uint64_t ticks = goldfish_rtc_get_count(s);
> +    uint64_t event = s->alarm_next;
> +
> +    if (event <= ticks) {
> +        goldfish_rtc_clear_alarm(s);
> +        goldfish_rtc_interrupt(s);
> +    } else {
> +        int64_t now = qemu_clock_get_ns(rtc_clock);
> +        timer_mod(s->timer, now + (event - ticks));
> +        s->alarm_running = 1;
> +    }
> +}
> +
> +static uint64_t goldfish_rtc_read(void *opaque, hwaddr offset,
> +                                  unsigned size)
> +{
> +    GoldfishRTCState *s = (GoldfishRTCState *)opaque;
> +    uint64_t r;
> +
> +    switch (offset) {
> +    case RTC_TIME_LOW:
> +        r = goldfish_rtc_get_count(s) & 0xffffffff;
> +        break;
> +    case RTC_TIME_HIGH:
> +        r = goldfish_rtc_get_count(s) >> 32;
> +        break;
> +    case RTC_ALARM_LOW:
> +        r = s->alarm_next & 0xffffffff;
> +        break;
> +    case RTC_ALARM_HIGH:
> +        r = s->alarm_next >> 32;
> +        break;
> +    case RTC_IRQ_ENABLED:
> +        r = s->irq_enabled;
> +        break;
> +    case RTC_ALARM_STATUS:
> +        r = s->alarm_running;
> +        break;
> +    default:
> +        qemu_log_mask(LOG_GUEST_ERROR,
> +                      "goldfish_rtc_read: Bad offset 0x%x\n",
> (int)offset);
> +        r = 0;
> +        break;
> +    }
> +
> +    return r;
> +}
> +
> +static void goldfish_rtc_write(void *opaque, hwaddr offset,
> +                               uint64_t value, unsigned size)
> +{
> +    uint64_t current_tick, new_tick;
> +    GoldfishRTCState *s = (GoldfishRTCState *)opaque;
> +
> +    switch (offset) {
> +    case RTC_TIME_LOW:
> +        current_tick = goldfish_rtc_get_count(s);
> +        new_tick = current_tick & (0xffffffffULL << 32);
> +        new_tick |= value;
> +        s->tick_offset += new_tick - current_tick;
> +        break;
> +    case RTC_TIME_HIGH:
> +        current_tick = goldfish_rtc_get_count(s);
> +        new_tick = current_tick & 0xffffffffULL;
> +        new_tick |= (value << 32);
> +        s->tick_offset += new_tick - current_tick;
> +        break;
> +    case RTC_ALARM_LOW:
> +        s->alarm_next &= (0xffffffffULL << 32);
> +        s->alarm_next |= value;
> +        goldfish_rtc_set_alarm(s);
> +        break;
> +    case RTC_ALARM_HIGH:
> +        s->alarm_next &= 0xffffffffULL;
> +        s->alarm_next |= (value << 32);
> +        break;
> +    case RTC_IRQ_ENABLED:
> +        s->irq_enabled = (uint32_t)(value & 0x1);
> +        goldfish_rtc_update(s);
> +        break;
> +    case RTC_CLEAR_ALARM:
> +        goldfish_rtc_clear_alarm(s);
> +        break;
> +    case RTC_CLEAR_INTERRUPT:
> +        s->irq_pending = 0;
> +        goldfish_rtc_update(s);
> +        break;
> +    default:
> +        qemu_log_mask(LOG_GUEST_ERROR,
> +                      "goldfish_rtc_write: Bad offset 0x%x\n",
> (int)offset);
> +        break;
> +    }
> +}
> +
> +static int goldfish_rtc_pre_save(void *opaque)
> +{
> +    uint64_t delta;
> +    GoldfishRTCState *s = opaque;
> +
> +    /*
> +     * We want to migrate this offset, which sounds straightforward.
> +     * Unfortunately, we cannot directly pass tick_offset because
> +     * rtc_clock on destinetion Host might not be same source Host.
> +     *
> +     * To tackle, this we pass tick_offset relative to vm_clock from
> +     * source Host and make it relative to rtc_clock at destinetion Host.
> +     */
> +    delta = qemu_clock_get_ns(rtc_clock) -
> +            qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
> +    s->tick_offset_vmstate = s->tick_offset + delta;
> +
> +    return 0;
> +}
> +
> +static int goldfish_rtc_post_load(void *opaque, int version_id)
> +{
> +    uint64_t delta;
> +    GoldfishRTCState *s = opaque;
> +
> +    /*
> +     * We extract tick_offset from tick_offset_vmstate by doing
> +     * reverse math compared to pre_save() function.
> +     */
> +    delta = qemu_clock_get_ns(rtc_clock) -
> +            qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
> +    s->tick_offset = s->tick_offset_vmstate - delta;
> +
> +    return 0;
> +}
> +
> +static const MemoryRegionOps goldfish_rtc_ops = {
> +    .read = goldfish_rtc_read,
> +    .write = goldfish_rtc_write,
> +    .endianness = DEVICE_LITTLE_ENDIAN,
> +    .valid = {
> +        .min_access_size = 4,
> +        .max_access_size = 4
> +    }
> +};
> +
> +static const VMStateDescription goldfish_rtc_vmstate = {
> +    .name = TYPE_GOLDFISH_RTC,
> +    .version_id = 1,
> +    .pre_save = goldfish_rtc_pre_save,
> +    .post_load = goldfish_rtc_post_load,
> +    .fields = (VMStateField[]) {
> +        VMSTATE_UINT64(tick_offset_vmstate, GoldfishRTCState),
> +        VMSTATE_UINT64(alarm_next, GoldfishRTCState),
> +        VMSTATE_UINT32(alarm_running, GoldfishRTCState),
> +        VMSTATE_UINT32(irq_pending, GoldfishRTCState),
> +        VMSTATE_UINT32(irq_enabled, GoldfishRTCState),
> +        VMSTATE_END_OF_LIST()
> +    }
> +};
> +
> +static void goldfish_rtc_reset(DeviceState *dev)
> +{
> +    GoldfishRTCState *s = GOLDFISH_RTC(dev);
> +    struct tm tm;
> +
> +    timer_del(s->timer);
> +
> +    qemu_get_timedate(&tm, 0);
> +    s->tick_offset = mktimegm(&tm);
> +    s->tick_offset *= NANOSECONDS_PER_SECOND;
> +    s->tick_offset -= qemu_clock_get_ns(rtc_clock);
> +    s->tick_offset_vmstate = 0;
> +    s->alarm_next = 0;
> +    s->alarm_running = 0;
> +    s->irq_pending = 0;
> +    s->irq_enabled = 0;
> +}
> +
> +static void goldfish_rtc_realize(DeviceState *d, Error **errp)
> +{
> +    SysBusDevice *dev = SYS_BUS_DEVICE(d);
> +    GoldfishRTCState *s = GOLDFISH_RTC(d);
> +
> +    memory_region_init_io(&s->iomem, OBJECT(s), &goldfish_rtc_ops, s,
> +                          "goldfish_rtc", 0x1000);
> +    sysbus_init_mmio(dev, &s->iomem);
> +
> +    sysbus_init_irq(dev, &s->irq);
> +
> +    s->timer = timer_new_ns(rtc_clock, goldfish_rtc_interrupt, s);
> +}
> +
> +static void goldfish_rtc_class_init(ObjectClass *klass, void *data)
> +{
> +    DeviceClass *dc = DEVICE_CLASS(klass);
> +
> +    dc->realize = goldfish_rtc_realize;
> +    dc->reset = goldfish_rtc_reset;
> +    dc->vmsd = &goldfish_rtc_vmstate;
> +}
> +
> +static const TypeInfo goldfish_rtc_info = {
> +    .name          = TYPE_GOLDFISH_RTC,
> +    .parent        = TYPE_SYS_BUS_DEVICE,
> +    .instance_size = sizeof(GoldfishRTCState),
> +    .class_init    = goldfish_rtc_class_init,
> +};
> +
> +static void goldfish_rtc_register_types(void)
> +{
> +    type_register_static(&goldfish_rtc_info);
> +}
> +
> +type_init(goldfish_rtc_register_types)
> diff --git a/include/hw/timer/goldfish_rtc.h b/include/hw/timer/goldfish_
> rtc.h
> new file mode 100644
> index 0000000000..dfb6d70b86
> --- /dev/null
> +++ b/include/hw/timer/goldfish_rtc.h
> @@ -0,0 +1,46 @@
> +/*
> + * Goldfish virtual platform RTC
> + *
> + * Copyright (C) 2019 Western Digital Corporation or its affiliates.
> + *
> + * For more details on Google Goldfish virtual platform refer:
> + * https://android.googlesource.com/platform/external/qemu/+/
> master/docs/GOLDFISH-VIRTUAL-HARDWARE.TXT
> + *
> + * 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/>.
> + */
> +
> +#ifndef HW_TIMER_GOLDFISH_RTC_H
> +#define HW_TIMER_GOLDFISH_RTC_H
> +
> +#include "hw/sysbus.h"
> +
> +#define TYPE_GOLDFISH_RTC "goldfish_rtc"
> +#define GOLDFISH_RTC(obj) \
> +OBJECT_CHECK(GoldfishRTCState, (obj), TYPE_GOLDFISH_RTC)
> +
> +typedef struct GoldfishRTCState {
> +    SysBusDevice parent_obj;
> +
> +    MemoryRegion iomem;
> +    QEMUTimer *timer;
> +    qemu_irq irq;
> +
> +    uint64_t tick_offset;
> +    uint64_t tick_offset_vmstate;
> +    uint64_t alarm_next;
> +    uint32_t alarm_running;
> +    uint32_t irq_pending;
> +    uint32_t irq_enabled;
> +} GoldfishRTCState;
> +
> +#endif
> --
> 2.17.1
>
>
>

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^ permalink raw reply	[flat|nested] 11+ messages in thread

* RE: [PATCH v3 1/2] hw: timer: Add Goldfish RTC device
  2019-10-18 20:59   ` Alistair Francis
@ 2019-10-19  4:21     ` Anup Patel
  0 siblings, 0 replies; 11+ messages in thread
From: Anup Patel @ 2019-10-19  4:21 UTC (permalink / raw)
  To: Alistair Francis
  Cc: Peter Maydell, qemu-riscv@nongnu.org, Sagar Karandikar,
	Bastian Koppelmann, Palmer Dabbelt, qemu-devel@nongnu.org,
	Atish Patra, Alistair Francis, Anup Patel



> -----Original Message-----
> From: Alistair Francis <alistair23@gmail.com>
> Sent: Saturday, October 19, 2019 2:29 AM
> To: Anup Patel <Anup.Patel@wdc.com>
> Cc: Peter Maydell <peter.maydell@linaro.org>; Palmer Dabbelt
> <palmer@sifive.com>; Alistair Francis <Alistair.Francis@wdc.com>; Sagar
> Karandikar <sagark@eecs.berkeley.edu>; Bastian Koppelmann
> <kbastian@mail.uni-paderborn.de>; Atish Patra <Atish.Patra@wdc.com>;
> qemu-riscv@nongnu.org; qemu-devel@nongnu.org; Anup Patel
> <anup@brainfault.org>
> Subject: Re: [PATCH v3 1/2] hw: timer: Add Goldfish RTC device
> 
> On Tue, Oct 15, 2019 at 1:36 AM Anup Patel <Anup.Patel@wdc.com> wrote:
> >
> > This patch adds model for Google Goldfish virtual platform RTC device.
> >
> > We will be adding Goldfish RTC device to the QEMU RISC-V virt machine
> > for providing real date-time to Guest Linux. The corresponding Linux
> > driver for Goldfish RTC device is already available in upstream Linux.
> >
> > For now, VM migration support is available but untested for Goldfish
> > RTC device. It will be hardened in-future when we implement VM
> > migration for KVM RISC-V.
> >
> > Signed-off-by: Anup Patel <anup.patel@wdc.com>
> > ---
> >  hw/rtc/Kconfig                  |   3 +
> >  hw/rtc/Makefile.objs            |   1 +
> >  hw/rtc/goldfish_rtc.c           | 278 ++++++++++++++++++++++++++++++++
> >  include/hw/timer/goldfish_rtc.h |  46 ++++++
> >  4 files changed, 328 insertions(+)
> >  create mode 100644 hw/rtc/goldfish_rtc.c  create mode 100644
> > include/hw/timer/goldfish_rtc.h
> >
> > diff --git a/hw/rtc/Kconfig b/hw/rtc/Kconfig index
> > 45daa8d655..bafe6ac2c9 100644
> > --- a/hw/rtc/Kconfig
> > +++ b/hw/rtc/Kconfig
> > @@ -21,3 +21,6 @@ config MC146818RTC
> >
> >  config SUN4V_RTC
> >      bool
> > +
> > +config GOLDFISH_RTC
> > +    bool
> > diff --git a/hw/rtc/Makefile.objs b/hw/rtc/Makefile.objs index
> > 8dc9fcd3a9..aa208d0d10 100644
> > --- a/hw/rtc/Makefile.objs
> > +++ b/hw/rtc/Makefile.objs
> > @@ -11,3 +11,4 @@ common-obj-$(CONFIG_EXYNOS4) +=
> exynos4210_rtc.o
> >  obj-$(CONFIG_MC146818RTC) += mc146818rtc.o
> >  common-obj-$(CONFIG_SUN4V_RTC) += sun4v-rtc.o
> >  common-obj-$(CONFIG_ASPEED_SOC) += aspeed_rtc.o
> > +common-obj-$(CONFIG_GOLDFISH_RTC) += goldfish_rtc.o
> > diff --git a/hw/rtc/goldfish_rtc.c b/hw/rtc/goldfish_rtc.c new file
> > mode 100644 index 0000000000..223616ed75
> > --- /dev/null
> > +++ b/hw/rtc/goldfish_rtc.c
> > @@ -0,0 +1,278 @@
> > +/*
> > + * Goldfish virtual platform RTC
> > + *
> > + * Copyright (C) 2019 Western Digital Corporation or its affiliates.
> > + *
> > + * For more details on Google Goldfish virtual platform refer:
> > + *
> >
> +https://android.googlesource.com/platform/external/qemu/+/master/doc
> s
> > +/GOLDFISH-VIRTUAL-HARDWARE.TXT
> > + *
> > + * 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-common.h"
> > +#include "hw/timer/goldfish_rtc.h"
> > +#include "migration/vmstate.h"
> > +#include "hw/irq.h"
> > +#include "hw/qdev-properties.h"
> > +#include "hw/sysbus.h"
> > +#include "qemu/timer.h"
> > +#include "sysemu/sysemu.h"
> > +#include "qemu/cutils.h"
> > +#include "qemu/log.h"
> > +
> > +#define RTC_TIME_LOW            0x00
> > +#define RTC_TIME_HIGH           0x04
> > +#define RTC_ALARM_LOW           0x08
> > +#define RTC_ALARM_HIGH          0x0c
> > +#define RTC_IRQ_ENABLED         0x10
> > +#define RTC_CLEAR_ALARM         0x14
> > +#define RTC_ALARM_STATUS        0x18
> > +#define RTC_CLEAR_INTERRUPT     0x1c
> > +
> > +static void goldfish_rtc_update(GoldfishRTCState *s) {
> > +    qemu_set_irq(s->irq, (s->irq_pending & s->irq_enabled) ? 1 : 0);
> > +}
> > +
> > +static void goldfish_rtc_interrupt(void *opaque) {
> > +    GoldfishRTCState *s = (GoldfishRTCState *)opaque;
> > +
> > +    s->alarm_running = 0;
> > +    s->irq_pending = 1;
> > +    goldfish_rtc_update(s);
> > +}
> > +
> > +static uint64_t goldfish_rtc_get_count(GoldfishRTCState *s) {
> > +    return s->tick_offset + (uint64_t)qemu_clock_get_ns(rtc_clock);
> > +}
> > +
> > +static void goldfish_rtc_clear_alarm(GoldfishRTCState *s) {
> > +    timer_del(s->timer);
> > +    s->alarm_running = 0;
> > +}
> > +
> > +static void goldfish_rtc_set_alarm(GoldfishRTCState *s) {
> > +    uint64_t ticks = goldfish_rtc_get_count(s);
> > +    uint64_t event = s->alarm_next;
> > +
> > +    if (event <= ticks) {
> > +        goldfish_rtc_clear_alarm(s);
> > +        goldfish_rtc_interrupt(s);
> > +    } else {
> > +        int64_t now = qemu_clock_get_ns(rtc_clock);
> > +        timer_mod(s->timer, now + (event - ticks));
> 
> Isn't this just: event - s->tick_offset?

Yes, effectively it is "event - s->tick_offset" but I felt
current code is more readable.

I think I will just add a detailed comment here that
" now + (event - ticks) = event - s->tick_offset" and
use "event - s->tick_offset".

> 
> > +        s->alarm_running = 1;
> > +    }
> > +}
> > +
> > +static uint64_t goldfish_rtc_read(void *opaque, hwaddr offset,
> > +                                  unsigned size) {
> > +    GoldfishRTCState *s = (GoldfishRTCState *)opaque;
> > +    uint64_t r;
> 
> There should be a trace or debug print showing read/write operations.

Sure, I will add in next revision.

> 
> > +
> > +    switch (offset) {
> > +    case RTC_TIME_LOW:
> > +        r = goldfish_rtc_get_count(s) & 0xffffffff;
> > +        break;
> > +    case RTC_TIME_HIGH:
> > +        r = goldfish_rtc_get_count(s) >> 32;
> > +        break;
> > +    case RTC_ALARM_LOW:
> > +        r = s->alarm_next & 0xffffffff;
> > +        break;
> > +    case RTC_ALARM_HIGH:
> > +        r = s->alarm_next >> 32;
> > +        break;
> > +    case RTC_IRQ_ENABLED:
> > +        r = s->irq_enabled;
> > +        break;
> > +    case RTC_ALARM_STATUS:
> > +        r = s->alarm_running;
> > +        break;
> > +    default:
> > +        qemu_log_mask(LOG_GUEST_ERROR,
> > +                      "goldfish_rtc_read: Bad offset 0x%x\n", (int)offset);
> > +        r = 0;
> 
> Just set 0 as the init value and remove this.

Okay, sure.

> 
> > +        break;
> > +    }
> > +
> > +    return r;
> > +}
> > +
> > +static void goldfish_rtc_write(void *opaque, hwaddr offset,
> > +                               uint64_t value, unsigned size) {
> > +    uint64_t current_tick, new_tick;
> > +    GoldfishRTCState *s = (GoldfishRTCState *)opaque;
> 
> The state struct should be first.

Okay, I will update.

> 
> > +
> > +    switch (offset) {
> > +    case RTC_TIME_LOW:
> > +        current_tick = goldfish_rtc_get_count(s);
> > +        new_tick = current_tick & (0xffffffffULL << 32);
> > +        new_tick |= value;
> > +        s->tick_offset += new_tick - current_tick;
> > +        break;
> > +    case RTC_TIME_HIGH:
> > +        current_tick = goldfish_rtc_get_count(s);
> > +        new_tick = current_tick & 0xffffffffULL;
> > +        new_tick |= (value << 32);
> > +        s->tick_offset += new_tick - current_tick;
> > +        break;
> > +    case RTC_ALARM_LOW:
> > +        s->alarm_next &= (0xffffffffULL << 32);
> > +        s->alarm_next |= value;
> > +        goldfish_rtc_set_alarm(s);
> > +        break;
> > +    case RTC_ALARM_HIGH:
> > +        s->alarm_next &= 0xffffffffULL;
> > +        s->alarm_next |= (value << 32);
> > +        break;
> > +    case RTC_IRQ_ENABLED:
> > +        s->irq_enabled = (uint32_t)(value & 0x1);
> > +        goldfish_rtc_update(s);
> > +        break;
> > +    case RTC_CLEAR_ALARM:
> > +        goldfish_rtc_clear_alarm(s);
> > +        break;
> > +    case RTC_CLEAR_INTERRUPT:
> > +        s->irq_pending = 0;
> > +        goldfish_rtc_update(s);
> > +        break;
> > +    default:
> > +        qemu_log_mask(LOG_GUEST_ERROR,
> > +                      "goldfish_rtc_write: Bad offset 0x%x\n", (int)offset);
> > +        break;
> > +    }
> > +}
> > +
> > +static int goldfish_rtc_pre_save(void *opaque) {
> > +    uint64_t delta;
> > +    GoldfishRTCState *s = opaque;
> > +
> > +    /*
> > +     * We want to migrate this offset, which sounds straightforward.
> > +     * Unfortunately, we cannot directly pass tick_offset because
> > +     * rtc_clock on destinetion Host might not be same source Host.
> 
> s/destinetion/destination/g
> 
> and below as well.

Sure, I will fix the typo.

> 
> Alistair
> 
> > +     *
> > +     * To tackle, this we pass tick_offset relative to vm_clock from
> > +     * source Host and make it relative to rtc_clock at destinetion Host.
> > +     */
> > +    delta = qemu_clock_get_ns(rtc_clock) -
> > +            qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
> > +    s->tick_offset_vmstate = s->tick_offset + delta;
> > +
> > +    return 0;
> > +}
> > +
> > +static int goldfish_rtc_post_load(void *opaque, int version_id) {
> > +    uint64_t delta;
> > +    GoldfishRTCState *s = opaque;
> > +
> > +    /*
> > +     * We extract tick_offset from tick_offset_vmstate by doing
> > +     * reverse math compared to pre_save() function.
> > +     */
> > +    delta = qemu_clock_get_ns(rtc_clock) -
> > +            qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
> > +    s->tick_offset = s->tick_offset_vmstate - delta;
> > +
> > +    return 0;
> > +}
> > +
> > +static const MemoryRegionOps goldfish_rtc_ops = {
> > +    .read = goldfish_rtc_read,
> > +    .write = goldfish_rtc_write,
> > +    .endianness = DEVICE_LITTLE_ENDIAN,
> > +    .valid = {
> > +        .min_access_size = 4,
> > +        .max_access_size = 4
> > +    }
> > +};
> > +
> > +static const VMStateDescription goldfish_rtc_vmstate = {
> > +    .name = TYPE_GOLDFISH_RTC,
> > +    .version_id = 1,
> > +    .pre_save = goldfish_rtc_pre_save,
> > +    .post_load = goldfish_rtc_post_load,
> > +    .fields = (VMStateField[]) {
> > +        VMSTATE_UINT64(tick_offset_vmstate, GoldfishRTCState),
> > +        VMSTATE_UINT64(alarm_next, GoldfishRTCState),
> > +        VMSTATE_UINT32(alarm_running, GoldfishRTCState),
> > +        VMSTATE_UINT32(irq_pending, GoldfishRTCState),
> > +        VMSTATE_UINT32(irq_enabled, GoldfishRTCState),
> > +        VMSTATE_END_OF_LIST()
> > +    }
> > +};
> > +
> > +static void goldfish_rtc_reset(DeviceState *dev) {
> > +    GoldfishRTCState *s = GOLDFISH_RTC(dev);
> > +    struct tm tm;
> > +
> > +    timer_del(s->timer);
> > +
> > +    qemu_get_timedate(&tm, 0);
> > +    s->tick_offset = mktimegm(&tm);
> > +    s->tick_offset *= NANOSECONDS_PER_SECOND;
> > +    s->tick_offset -= qemu_clock_get_ns(rtc_clock);
> > +    s->tick_offset_vmstate = 0;
> > +    s->alarm_next = 0;
> > +    s->alarm_running = 0;
> > +    s->irq_pending = 0;
> > +    s->irq_enabled = 0;
> > +}
> > +
> > +static void goldfish_rtc_realize(DeviceState *d, Error **errp) {
> > +    SysBusDevice *dev = SYS_BUS_DEVICE(d);
> > +    GoldfishRTCState *s = GOLDFISH_RTC(d);
> > +
> > +    memory_region_init_io(&s->iomem, OBJECT(s), &goldfish_rtc_ops, s,
> > +                          "goldfish_rtc", 0x1000);
> > +    sysbus_init_mmio(dev, &s->iomem);
> > +
> > +    sysbus_init_irq(dev, &s->irq);
> > +
> > +    s->timer = timer_new_ns(rtc_clock, goldfish_rtc_interrupt, s); }
> > +
> > +static void goldfish_rtc_class_init(ObjectClass *klass, void *data) {
> > +    DeviceClass *dc = DEVICE_CLASS(klass);
> > +
> > +    dc->realize = goldfish_rtc_realize;
> > +    dc->reset = goldfish_rtc_reset;
> > +    dc->vmsd = &goldfish_rtc_vmstate; }
> > +
> > +static const TypeInfo goldfish_rtc_info = {
> > +    .name          = TYPE_GOLDFISH_RTC,
> > +    .parent        = TYPE_SYS_BUS_DEVICE,
> > +    .instance_size = sizeof(GoldfishRTCState),
> > +    .class_init    = goldfish_rtc_class_init,
> > +};
> > +
> > +static void goldfish_rtc_register_types(void) {
> > +    type_register_static(&goldfish_rtc_info);
> > +}
> > +
> > +type_init(goldfish_rtc_register_types)
> > diff --git a/include/hw/timer/goldfish_rtc.h
> > b/include/hw/timer/goldfish_rtc.h new file mode 100644 index
> > 0000000000..dfb6d70b86
> > --- /dev/null
> > +++ b/include/hw/timer/goldfish_rtc.h
> > @@ -0,0 +1,46 @@
> > +/*
> > + * Goldfish virtual platform RTC
> > + *
> > + * Copyright (C) 2019 Western Digital Corporation or its affiliates.
> > + *
> > + * For more details on Google Goldfish virtual platform refer:
> > + *
> >
> +https://android.googlesource.com/platform/external/qemu/+/master/doc
> s
> > +/GOLDFISH-VIRTUAL-HARDWARE.TXT
> > + *
> > + * 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/>.
> > + */
> > +
> > +#ifndef HW_TIMER_GOLDFISH_RTC_H
> > +#define HW_TIMER_GOLDFISH_RTC_H
> > +
> > +#include "hw/sysbus.h"
> > +
> > +#define TYPE_GOLDFISH_RTC "goldfish_rtc"
> > +#define GOLDFISH_RTC(obj) \
> > +OBJECT_CHECK(GoldfishRTCState, (obj), TYPE_GOLDFISH_RTC)
> > +
> > +typedef struct GoldfishRTCState {
> > +    SysBusDevice parent_obj;
> > +
> > +    MemoryRegion iomem;
> > +    QEMUTimer *timer;
> > +    qemu_irq irq;
> > +
> > +    uint64_t tick_offset;
> > +    uint64_t tick_offset_vmstate;
> > +    uint64_t alarm_next;
> > +    uint32_t alarm_running;
> > +    uint32_t irq_pending;
> > +    uint32_t irq_enabled;
> > +} GoldfishRTCState;
> > +
> > +#endif
> > --
> > 2.17.1
> >
> >

Regards,
Anup

^ permalink raw reply	[flat|nested] 11+ messages in thread

* RE: [PATCH v3 1/2] hw: timer: Add Goldfish RTC device
  2019-10-18 21:15   ` Aleksandar Markovic
@ 2019-10-19  4:33     ` Anup Patel
  2019-10-19  6:21       ` Aleksandar Markovic
  0 siblings, 1 reply; 11+ messages in thread
From: Anup Patel @ 2019-10-19  4:33 UTC (permalink / raw)
  To: Aleksandar Markovic
  Cc: Peter Maydell, qemu-riscv@nongnu.org, Sagar Karandikar,
	Bastian Koppelmann, Palmer Dabbelt, qemu-devel@nongnu.org,
	Atish Patra, Alistair Francis, Anup Patel

Hi,

From: Aleksandar Markovic <aleksandar.m.mail@gmail.com> 
Sent: Saturday, October 19, 2019 2:45 AM
To: Anup Patel <Anup.Patel@wdc.com>
Cc: Peter Maydell <peter.maydell@linaro.org>; Palmer Dabbelt <palmer@sifive.com>; Alistair Francis <Alistair.Francis@wdc.com>; Sagar Karandikar <sagark@eecs.berkeley.edu>; Bastian Koppelmann <kbastian@mail.uni-paderborn.de>; Atish Patra <Atish.Patra@wdc.com>; qemu-riscv@nongnu.org; qemu-devel@nongnu.org; Anup Patel <anup@brainfault.org>
Subject: Re: [PATCH v3 1/2] hw: timer: Add Goldfish RTC device

ū

On Tuesday, October 15, 2019, Anup Patel <mailto:Anup.Patel@wdc.com> wrote:
This patch adds model for Google Goldfish virtual platform RTC device.

We will be adding Goldfish RTC device to the QEMU RISC-V virt machine
for providing real date-time to Guest Linux. The corresponding Linux
driver for Goldfish RTC device is already available in upstream Linux.

For now, VM migration support is available but untested for Goldfish RTC
device. It will be hardened in-future when we implement VM migration for
KVM RISC-V.

Signed-off-by: Anup Patel <mailto:anup.patel@wdc.com>
---
 hw/rtc/Kconfig                  |   3 +
 hw/rtc/Makefile.objs            |   1 +
 hw/rtc/goldfish_rtc.c           | 278 ++++++++++++++++++++++++++++++++
 include/hw/timer/goldfish_rtc.h |  46 ++++++
 4 files changed, 328 insertions(+)
 create mode 100644 hw/rtc/goldfish_rtc.c
 create mode 100644 include/hw/timer/goldfish_rtc.h

Do you plan to add some other devices from Goldfish platform?

[Anup] Nopes, we just needed a simple RTC device for RISC-V
[Anup] virt machine hence this patch. 

[Anup] Most of the required devices are already there in
[Anup] the VirtIO spec. The RTC device was missing in
[Anup] VirtIO spec so instead of creating new virtual RTC
[Anup] device we just re-use Goldfish RTC. This help us
[Anup] re-use the Linux Goldfish RTC driver.

Did you base your code on Android emulator code?

[Anup] Nopes, the android emulator code seemed too simple
[Anup] and lacking. In fact, the Linux Goldfish RTC driver does
[Anup] much more.

[Anup] Based on the documentation and Linux Goldfish RTC
[Anup] driver, I wrote it from scratch.

[Anup] I first added Goldfish RTC emulator to Xvisor RISC-V
[Anup] virt machine. Got it working over there and then
[Anup] ported it to QEMU. For qemu emulation, I looked
[Anup] at existing RTC emulators (such as PL031) for QEMU
[Anup] API usage.

Related to the previous question, are you sure the copyright line should go to Western Digital only?

[Anup] I thought copyright will be of implementer hence I
[Anup] put Western Digital only. The spec and Linux driver
[Anup] can be written by totally different folks.

Regards,
Anup
 
diff --git a/hw/rtc/Kconfig b/hw/rtc/Kconfig
index 45daa8d655..bafe6ac2c9 100644
--- a/hw/rtc/Kconfig
+++ b/hw/rtc/Kconfig
@@ -21,3 +21,6 @@ config MC146818RTC

 config SUN4V_RTC
     bool
+
+config GOLDFISH_RTC
+    bool
diff --git a/hw/rtc/Makefile.objs b/hw/rtc/Makefile.objs
index 8dc9fcd3a9..aa208d0d10 100644
--- a/hw/rtc/Makefile.objs
+++ b/hw/rtc/Makefile.objs
@@ -11,3 +11,4 @@ common-obj-$(CONFIG_EXYNOS4) += exynos4210_rtc.o
 obj-$(CONFIG_MC146818RTC) += mc146818rtc.o
 common-obj-$(CONFIG_SUN4V_RTC) += sun4v-rtc.o
 common-obj-$(CONFIG_ASPEED_SOC) += aspeed_rtc.o
+common-obj-$(CONFIG_GOLDFISH_RTC) += goldfish_rtc.o
diff --git a/hw/rtc/goldfish_rtc.c b/hw/rtc/goldfish_rtc.c
new file mode 100644
index 0000000000..223616ed75
--- /dev/null
+++ b/hw/rtc/goldfish_rtc.c
@@ -0,0 +1,278 @@
+/*
+ * Goldfish virtual platform RTC
+ *
+ * Copyright (C) 2019 Western Digital Corporation or its affiliates.
+ *
+ * For more details on Google Goldfish virtual platform refer:
+ * https://android.googlesource.com/platform/external/qemu/+/master/docs/GOLDFISH-VIRTUAL-HARDWARE.TXT
+ *
+ * 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-common.h"
+#include "hw/timer/goldfish_rtc.h"
+#include "migration/vmstate.h"
+#include "hw/irq.h"
+#include "hw/qdev-properties.h"
+#include "hw/sysbus.h"
+#include "qemu/timer.h"
+#include "sysemu/sysemu.h"
+#include "qemu/cutils.h"
+#include "qemu/log.h"
+
+#define RTC_TIME_LOW            0x00
+#define RTC_TIME_HIGH           0x04
+#define RTC_ALARM_LOW           0x08
+#define RTC_ALARM_HIGH          0x0c
+#define RTC_IRQ_ENABLED         0x10
+#define RTC_CLEAR_ALARM         0x14
+#define RTC_ALARM_STATUS        0x18
+#define RTC_CLEAR_INTERRUPT     0x1c
+
+static void goldfish_rtc_update(GoldfishRTCState *s)
+{
+    qemu_set_irq(s->irq, (s->irq_pending & s->irq_enabled) ? 1 : 0);
+}
+
+static void goldfish_rtc_interrupt(void *opaque)
+{
+    GoldfishRTCState *s = (GoldfishRTCState *)opaque;
+
+    s->alarm_running = 0;
+    s->irq_pending = 1;
+    goldfish_rtc_update(s);
+}
+
+static uint64_t goldfish_rtc_get_count(GoldfishRTCState *s)
+{
+    return s->tick_offset + (uint64_t)qemu_clock_get_ns(rtc_clock);
+}
+
+static void goldfish_rtc_clear_alarm(GoldfishRTCState *s)
+{
+    timer_del(s->timer);
+    s->alarm_running = 0;
+}
+
+static void goldfish_rtc_set_alarm(GoldfishRTCState *s)
+{
+    uint64_t ticks = goldfish_rtc_get_count(s);
+    uint64_t event = s->alarm_next;
+
+    if (event <= ticks) {
+        goldfish_rtc_clear_alarm(s);
+        goldfish_rtc_interrupt(s);
+    } else {
+        int64_t now = qemu_clock_get_ns(rtc_clock);
+        timer_mod(s->timer, now + (event - ticks));
+        s->alarm_running = 1;
+    }
+}
+
+static uint64_t goldfish_rtc_read(void *opaque, hwaddr offset,
+                                  unsigned size)
+{
+    GoldfishRTCState *s = (GoldfishRTCState *)opaque;
+    uint64_t r;
+
+    switch (offset) {
+    case RTC_TIME_LOW:
+        r = goldfish_rtc_get_count(s) & 0xffffffff;
+        break;
+    case RTC_TIME_HIGH:
+        r = goldfish_rtc_get_count(s) >> 32;
+        break;
+    case RTC_ALARM_LOW:
+        r = s->alarm_next & 0xffffffff;
+        break;
+    case RTC_ALARM_HIGH:
+        r = s->alarm_next >> 32;
+        break;
+    case RTC_IRQ_ENABLED:
+        r = s->irq_enabled;
+        break;
+    case RTC_ALARM_STATUS:
+        r = s->alarm_running;
+        break;
+    default:
+        qemu_log_mask(LOG_GUEST_ERROR,
+                      "goldfish_rtc_read: Bad offset 0x%x\n", (int)offset);
+        r = 0;
+        break;
+    }
+
+    return r;
+}
+
+static void goldfish_rtc_write(void *opaque, hwaddr offset,
+                               uint64_t value, unsigned size)
+{
+    uint64_t current_tick, new_tick;
+    GoldfishRTCState *s = (GoldfishRTCState *)opaque;
+
+    switch (offset) {
+    case RTC_TIME_LOW:
+        current_tick = goldfish_rtc_get_count(s);
+        new_tick = current_tick & (0xffffffffULL << 32);
+        new_tick |= value;
+        s->tick_offset += new_tick - current_tick;
+        break;
+    case RTC_TIME_HIGH:
+        current_tick = goldfish_rtc_get_count(s);
+        new_tick = current_tick & 0xffffffffULL;
+        new_tick |= (value << 32);
+        s->tick_offset += new_tick - current_tick;
+        break;
+    case RTC_ALARM_LOW:
+        s->alarm_next &= (0xffffffffULL << 32);
+        s->alarm_next |= value;
+        goldfish_rtc_set_alarm(s);
+        break;
+    case RTC_ALARM_HIGH:
+        s->alarm_next &= 0xffffffffULL;
+        s->alarm_next |= (value << 32);
+        break;
+    case RTC_IRQ_ENABLED:
+        s->irq_enabled = (uint32_t)(value & 0x1);
+        goldfish_rtc_update(s);
+        break;
+    case RTC_CLEAR_ALARM:
+        goldfish_rtc_clear_alarm(s);
+        break;
+    case RTC_CLEAR_INTERRUPT:
+        s->irq_pending = 0;
+        goldfish_rtc_update(s);
+        break;
+    default:
+        qemu_log_mask(LOG_GUEST_ERROR,
+                      "goldfish_rtc_write: Bad offset 0x%x\n", (int)offset);
+        break;
+    }
+}
+
+static int goldfish_rtc_pre_save(void *opaque)
+{
+    uint64_t delta;
+    GoldfishRTCState *s = opaque;
+
+    /*
+     * We want to migrate this offset, which sounds straightforward.
+     * Unfortunately, we cannot directly pass tick_offset because
+     * rtc_clock on destinetion Host might not be same source Host.
+     *
+     * To tackle, this we pass tick_offset relative to vm_clock from
+     * source Host and make it relative to rtc_clock at destinetion Host.
+     */
+    delta = qemu_clock_get_ns(rtc_clock) -
+            qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
+    s->tick_offset_vmstate = s->tick_offset + delta;
+
+    return 0;
+}
+
+static int goldfish_rtc_post_load(void *opaque, int version_id)
+{
+    uint64_t delta;
+    GoldfishRTCState *s = opaque;
+
+    /*
+     * We extract tick_offset from tick_offset_vmstate by doing
+     * reverse math compared to pre_save() function.
+     */
+    delta = qemu_clock_get_ns(rtc_clock) -
+            qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
+    s->tick_offset = s->tick_offset_vmstate - delta;
+
+    return 0;
+}
+
+static const MemoryRegionOps goldfish_rtc_ops = {
+    .read = goldfish_rtc_read,
+    .write = goldfish_rtc_write,
+    .endianness = DEVICE_LITTLE_ENDIAN,
+    .valid = {
+        .min_access_size = 4,
+        .max_access_size = 4
+    }
+};
+
+static const VMStateDescription goldfish_rtc_vmstate = {
+    .name = TYPE_GOLDFISH_RTC,
+    .version_id = 1,
+    .pre_save = goldfish_rtc_pre_save,
+    .post_load = goldfish_rtc_post_load,
+    .fields = (VMStateField[]) {
+        VMSTATE_UINT64(tick_offset_vmstate, GoldfishRTCState),
+        VMSTATE_UINT64(alarm_next, GoldfishRTCState),
+        VMSTATE_UINT32(alarm_running, GoldfishRTCState),
+        VMSTATE_UINT32(irq_pending, GoldfishRTCState),
+        VMSTATE_UINT32(irq_enabled, GoldfishRTCState),
+        VMSTATE_END_OF_LIST()
+    }
+};
+
+static void goldfish_rtc_reset(DeviceState *dev)
+{
+    GoldfishRTCState *s = GOLDFISH_RTC(dev);
+    struct tm tm;
+
+    timer_del(s->timer);
+
+    qemu_get_timedate(&tm, 0);
+    s->tick_offset = mktimegm(&tm);
+    s->tick_offset *= NANOSECONDS_PER_SECOND;
+    s->tick_offset -= qemu_clock_get_ns(rtc_clock);
+    s->tick_offset_vmstate = 0;
+    s->alarm_next = 0;
+    s->alarm_running = 0;
+    s->irq_pending = 0;
+    s->irq_enabled = 0;
+}
+
+static void goldfish_rtc_realize(DeviceState *d, Error **errp)
+{
+    SysBusDevice *dev = SYS_BUS_DEVICE(d);
+    GoldfishRTCState *s = GOLDFISH_RTC(d);
+
+    memory_region_init_io(&s->iomem, OBJECT(s), &goldfish_rtc_ops, s,
+                          "goldfish_rtc", 0x1000);
+    sysbus_init_mmio(dev, &s->iomem);
+
+    sysbus_init_irq(dev, &s->irq);
+
+    s->timer = timer_new_ns(rtc_clock, goldfish_rtc_interrupt, s);
+}
+
+static void goldfish_rtc_class_init(ObjectClass *klass, void *data)
+{
+    DeviceClass *dc = DEVICE_CLASS(klass);
+
+    dc->realize = goldfish_rtc_realize;
+    dc->reset = goldfish_rtc_reset;
+    dc->vmsd = &goldfish_rtc_vmstate;
+}
+
+static const TypeInfo goldfish_rtc_info = {
+    .name          = TYPE_GOLDFISH_RTC,
+    .parent        = TYPE_SYS_BUS_DEVICE,
+    .instance_size = sizeof(GoldfishRTCState),
+    .class_init    = goldfish_rtc_class_init,
+};
+
+static void goldfish_rtc_register_types(void)
+{
+    type_register_static(&goldfish_rtc_info);
+}
+
+type_init(goldfish_rtc_register_types)
diff --git a/include/hw/timer/goldfish_rtc.h b/include/hw/timer/goldfish_rtc.h
new file mode 100644
index 0000000000..dfb6d70b86
--- /dev/null
+++ b/include/hw/timer/goldfish_rtc.h
@@ -0,0 +1,46 @@
+/*
+ * Goldfish virtual platform RTC
+ *
+ * Copyright (C) 2019 Western Digital Corporation or its affiliates.
+ *
+ * For more details on Google Goldfish virtual platform refer:
+ * https://android.googlesource.com/platform/external/qemu/+/master/docs/GOLDFISH-VIRTUAL-HARDWARE.TXT
+ *
+ * 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/>.
+ */
+
+#ifndef HW_TIMER_GOLDFISH_RTC_H
+#define HW_TIMER_GOLDFISH_RTC_H
+
+#include "hw/sysbus.h"
+
+#define TYPE_GOLDFISH_RTC "goldfish_rtc"
+#define GOLDFISH_RTC(obj) \
+OBJECT_CHECK(GoldfishRTCState, (obj), TYPE_GOLDFISH_RTC)
+
+typedef struct GoldfishRTCState {
+    SysBusDevice parent_obj;
+
+    MemoryRegion iomem;
+    QEMUTimer *timer;
+    qemu_irq irq;
+
+    uint64_t tick_offset;
+    uint64_t tick_offset_vmstate;
+    uint64_t alarm_next;
+    uint32_t alarm_running;
+    uint32_t irq_pending;
+    uint32_t irq_enabled;
+} GoldfishRTCState;
+
+#endif
-- 
2.17.1


^ permalink raw reply related	[flat|nested] 11+ messages in thread

* Re: [PATCH v3 1/2] hw: timer: Add Goldfish RTC device
  2019-10-19  4:33     ` Anup Patel
@ 2019-10-19  6:21       ` Aleksandar Markovic
  0 siblings, 0 replies; 11+ messages in thread
From: Aleksandar Markovic @ 2019-10-19  6:21 UTC (permalink / raw)
  To: Anup Patel
  Cc: Peter Maydell, qemu-riscv@nongnu.org, Sagar Karandikar,
	Bastian Koppelmann, Palmer Dabbelt, qemu-devel@nongnu.org,
	Atish Patra, Alistair Francis, Anup Patel

[-- Attachment #1: Type: text/plain, Size: 15026 bytes --]

On Saturday, October 19, 2019, Anup Patel <Anup.Patel@wdc.com> wrote:

> Hi,
>
> From: Aleksandar Markovic <aleksandar.m.mail@gmail.com>
> Sent: Saturday, October 19, 2019 2:45 AM
> To: Anup Patel <Anup.Patel@wdc.com>
> Cc: Peter Maydell <peter.maydell@linaro.org>; Palmer Dabbelt <
> palmer@sifive.com>; Alistair Francis <Alistair.Francis@wdc.com>; Sagar
> Karandikar <sagark@eecs.berkeley.edu>; Bastian Koppelmann <
> kbastian@mail.uni-paderborn.de>; Atish Patra <Atish.Patra@wdc.com>;
> qemu-riscv@nongnu.org; qemu-devel@nongnu.org; Anup Patel <
> anup@brainfault.org>
> Subject: Re: [PATCH v3 1/2] hw: timer: Add Goldfish RTC device
>
> ū
>
> On Tuesday, October 15, 2019, Anup Patel <mailto:Anup.Patel@wdc.com>
> wrote:
> This patch adds model for Google Goldfish virtual platform RTC device.
>
> We will be adding Goldfish RTC device to the QEMU RISC-V virt machine
> for providing real date-time to Guest Linux. The corresponding Linux
> driver for Goldfish RTC device is already available in upstream Linux.
>
> For now, VM migration support is available but untested for Goldfish RTC
> device. It will be hardened in-future when we implement VM migration for
> KVM RISC-V.
>
> Signed-off-by: Anup Patel <mailto:anup.patel@wdc.com>
> ---
>  hw/rtc/Kconfig                  |   3 +
>  hw/rtc/Makefile.objs            |   1 +
>  hw/rtc/goldfish_rtc.c           | 278 ++++++++++++++++++++++++++++++++
>  include/hw/timer/goldfish_rtc.h |  46 ++++++
>  4 files changed, 328 insertions(+)
>  create mode 100644 hw/rtc/goldfish_rtc.c
>  create mode 100644 include/hw/timer/goldfish_rtc.h
>
> Do you plan to add some other devices from Goldfish platform?
>
> [Anup] Nopes, we just needed a simple RTC device for RISC-V
> [Anup] virt machine hence this patch.
>
> [Anup] Most of the required devices are already there in
> [Anup] the VirtIO spec. The RTC device was missing in
> [Anup] VirtIO spec so instead of creating new virtual RTC
> [Anup] device we just re-use Goldfish RTC. This help us
> [Anup] re-use the Linux Goldfish RTC driver.
>
> Did you base your code on Android emulator code?
>
> [Anup] Nopes, the android emulator code seemed too simple
> [Anup] and lacking. In fact, the Linux Goldfish RTC driver does
> [Anup] much more.
>
> [Anup] Based on the documentation and Linux Goldfish RTC
> [Anup] driver, I wrote it from scratch.
>
>
Ok, that is great, nice work. I just wanted to doublecheck if we are OK
from the aspect of authorship. "Western Digital" in copyright preamble is
certainly fine in this case.

A.

[Anup] I first added Goldfish RTC emulator to Xvisor RISC-V
> [Anup] virt machine. Got it working over there and then
> [Anup] ported it to QEMU. For qemu emulation, I looked
> [Anup] at existing RTC emulators (such as PL031) for QEMU
> [Anup] API usage.
>
> Related to the previous question, are you sure the copyright line should
> go to Western Digital only?
>
> [Anup] I thought copyright will be of implementer hence I
> [Anup] put Western Digital only. The spec and Linux driver
> [Anup] can be written by totally different folks.
>
> Regards,
> Anup
>
> diff --git a/hw/rtc/Kconfig b/hw/rtc/Kconfig
> index 45daa8d655..bafe6ac2c9 100644
> --- a/hw/rtc/Kconfig
> +++ b/hw/rtc/Kconfig
> @@ -21,3 +21,6 @@ config MC146818RTC
>
>  config SUN4V_RTC
>      bool
> +
> +config GOLDFISH_RTC
> +    bool
> diff --git a/hw/rtc/Makefile.objs b/hw/rtc/Makefile.objs
> index 8dc9fcd3a9..aa208d0d10 100644
> --- a/hw/rtc/Makefile.objs
> +++ b/hw/rtc/Makefile.objs
> @@ -11,3 +11,4 @@ common-obj-$(CONFIG_EXYNOS4) += exynos4210_rtc.o
>  obj-$(CONFIG_MC146818RTC) += mc146818rtc.o
>  common-obj-$(CONFIG_SUN4V_RTC) += sun4v-rtc.o
>  common-obj-$(CONFIG_ASPEED_SOC) += aspeed_rtc.o
> +common-obj-$(CONFIG_GOLDFISH_RTC) += goldfish_rtc.o
> diff --git a/hw/rtc/goldfish_rtc.c b/hw/rtc/goldfish_rtc.c
> new file mode 100644
> index 0000000000..223616ed75
> --- /dev/null
> +++ b/hw/rtc/goldfish_rtc.c
> @@ -0,0 +1,278 @@
> +/*
> + * Goldfish virtual platform RTC
> + *
> + * Copyright (C) 2019 Western Digital Corporation or its affiliates.
> + *
> + * For more details on Google Goldfish virtual platform refer:
> + * https://android.googlesource.com/platform/external/qemu/+/
> master/docs/GOLDFISH-VIRTUAL-HARDWARE.TXT
> + *
> + * 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-common.h"
> +#include "hw/timer/goldfish_rtc.h"
> +#include "migration/vmstate.h"
> +#include "hw/irq.h"
> +#include "hw/qdev-properties.h"
> +#include "hw/sysbus.h"
> +#include "qemu/timer.h"
> +#include "sysemu/sysemu.h"
> +#include "qemu/cutils.h"
> +#include "qemu/log.h"
> +
> +#define RTC_TIME_LOW            0x00
> +#define RTC_TIME_HIGH           0x04
> +#define RTC_ALARM_LOW           0x08
> +#define RTC_ALARM_HIGH          0x0c
> +#define RTC_IRQ_ENABLED         0x10
> +#define RTC_CLEAR_ALARM         0x14
> +#define RTC_ALARM_STATUS        0x18
> +#define RTC_CLEAR_INTERRUPT     0x1c
> +
> +static void goldfish_rtc_update(GoldfishRTCState *s)
> +{
> +    qemu_set_irq(s->irq, (s->irq_pending & s->irq_enabled) ? 1 : 0);
> +}
> +
> +static void goldfish_rtc_interrupt(void *opaque)
> +{
> +    GoldfishRTCState *s = (GoldfishRTCState *)opaque;
> +
> +    s->alarm_running = 0;
> +    s->irq_pending = 1;
> +    goldfish_rtc_update(s);
> +}
> +
> +static uint64_t goldfish_rtc_get_count(GoldfishRTCState *s)
> +{
> +    return s->tick_offset + (uint64_t)qemu_clock_get_ns(rtc_clock);
> +}
> +
> +static void goldfish_rtc_clear_alarm(GoldfishRTCState *s)
> +{
> +    timer_del(s->timer);
> +    s->alarm_running = 0;
> +}
> +
> +static void goldfish_rtc_set_alarm(GoldfishRTCState *s)
> +{
> +    uint64_t ticks = goldfish_rtc_get_count(s);
> +    uint64_t event = s->alarm_next;
> +
> +    if (event <= ticks) {
> +        goldfish_rtc_clear_alarm(s);
> +        goldfish_rtc_interrupt(s);
> +    } else {
> +        int64_t now = qemu_clock_get_ns(rtc_clock);
> +        timer_mod(s->timer, now + (event - ticks));
> +        s->alarm_running = 1;
> +    }
> +}
> +
> +static uint64_t goldfish_rtc_read(void *opaque, hwaddr offset,
> +                                  unsigned size)
> +{
> +    GoldfishRTCState *s = (GoldfishRTCState *)opaque;
> +    uint64_t r;
> +
> +    switch (offset) {
> +    case RTC_TIME_LOW:
> +        r = goldfish_rtc_get_count(s) & 0xffffffff;
> +        break;
> +    case RTC_TIME_HIGH:
> +        r = goldfish_rtc_get_count(s) >> 32;
> +        break;
> +    case RTC_ALARM_LOW:
> +        r = s->alarm_next & 0xffffffff;
> +        break;
> +    case RTC_ALARM_HIGH:
> +        r = s->alarm_next >> 32;
> +        break;
> +    case RTC_IRQ_ENABLED:
> +        r = s->irq_enabled;
> +        break;
> +    case RTC_ALARM_STATUS:
> +        r = s->alarm_running;
> +        break;
> +    default:
> +        qemu_log_mask(LOG_GUEST_ERROR,
> +                      "goldfish_rtc_read: Bad offset 0x%x\n",
> (int)offset);
> +        r = 0;
> +        break;
> +    }
> +
> +    return r;
> +}
> +
> +static void goldfish_rtc_write(void *opaque, hwaddr offset,
> +                               uint64_t value, unsigned size)
> +{
> +    uint64_t current_tick, new_tick;
> +    GoldfishRTCState *s = (GoldfishRTCState *)opaque;
> +
> +    switch (offset) {
> +    case RTC_TIME_LOW:
> +        current_tick = goldfish_rtc_get_count(s);
> +        new_tick = current_tick & (0xffffffffULL << 32);
> +        new_tick |= value;
> +        s->tick_offset += new_tick - current_tick;
> +        break;
> +    case RTC_TIME_HIGH:
> +        current_tick = goldfish_rtc_get_count(s);
> +        new_tick = current_tick & 0xffffffffULL;
> +        new_tick |= (value << 32);
> +        s->tick_offset += new_tick - current_tick;
> +        break;
> +    case RTC_ALARM_LOW:
> +        s->alarm_next &= (0xffffffffULL << 32);
> +        s->alarm_next |= value;
> +        goldfish_rtc_set_alarm(s);
> +        break;
> +    case RTC_ALARM_HIGH:
> +        s->alarm_next &= 0xffffffffULL;
> +        s->alarm_next |= (value << 32);
> +        break;
> +    case RTC_IRQ_ENABLED:
> +        s->irq_enabled = (uint32_t)(value & 0x1);
> +        goldfish_rtc_update(s);
> +        break;
> +    case RTC_CLEAR_ALARM:
> +        goldfish_rtc_clear_alarm(s);
> +        break;
> +    case RTC_CLEAR_INTERRUPT:
> +        s->irq_pending = 0;
> +        goldfish_rtc_update(s);
> +        break;
> +    default:
> +        qemu_log_mask(LOG_GUEST_ERROR,
> +                      "goldfish_rtc_write: Bad offset 0x%x\n",
> (int)offset);
> +        break;
> +    }
> +}
> +
> +static int goldfish_rtc_pre_save(void *opaque)
> +{
> +    uint64_t delta;
> +    GoldfishRTCState *s = opaque;
> +
> +    /*
> +     * We want to migrate this offset, which sounds straightforward.
> +     * Unfortunately, we cannot directly pass tick_offset because
> +     * rtc_clock on destinetion Host might not be same source Host.
> +     *
> +     * To tackle, this we pass tick_offset relative to vm_clock from
> +     * source Host and make it relative to rtc_clock at destinetion Host.
> +     */
> +    delta = qemu_clock_get_ns(rtc_clock) -
> +            qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
> +    s->tick_offset_vmstate = s->tick_offset + delta;
> +
> +    return 0;
> +}
> +
> +static int goldfish_rtc_post_load(void *opaque, int version_id)
> +{
> +    uint64_t delta;
> +    GoldfishRTCState *s = opaque;
> +
> +    /*
> +     * We extract tick_offset from tick_offset_vmstate by doing
> +     * reverse math compared to pre_save() function.
> +     */
> +    delta = qemu_clock_get_ns(rtc_clock) -
> +            qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
> +    s->tick_offset = s->tick_offset_vmstate - delta;
> +
> +    return 0;
> +}
> +
> +static const MemoryRegionOps goldfish_rtc_ops = {
> +    .read = goldfish_rtc_read,
> +    .write = goldfish_rtc_write,
> +    .endianness = DEVICE_LITTLE_ENDIAN,
> +    .valid = {
> +        .min_access_size = 4,
> +        .max_access_size = 4
> +    }
> +};
> +
> +static const VMStateDescription goldfish_rtc_vmstate = {
> +    .name = TYPE_GOLDFISH_RTC,
> +    .version_id = 1,
> +    .pre_save = goldfish_rtc_pre_save,
> +    .post_load = goldfish_rtc_post_load,
> +    .fields = (VMStateField[]) {
> +        VMSTATE_UINT64(tick_offset_vmstate, GoldfishRTCState),
> +        VMSTATE_UINT64(alarm_next, GoldfishRTCState),
> +        VMSTATE_UINT32(alarm_running, GoldfishRTCState),
> +        VMSTATE_UINT32(irq_pending, GoldfishRTCState),
> +        VMSTATE_UINT32(irq_enabled, GoldfishRTCState),
> +        VMSTATE_END_OF_LIST()
> +    }
> +};
> +
> +static void goldfish_rtc_reset(DeviceState *dev)
> +{
> +    GoldfishRTCState *s = GOLDFISH_RTC(dev);
> +    struct tm tm;
> +
> +    timer_del(s->timer);
> +
> +    qemu_get_timedate(&tm, 0);
> +    s->tick_offset = mktimegm(&tm);
> +    s->tick_offset *= NANOSECONDS_PER_SECOND;
> +    s->tick_offset -= qemu_clock_get_ns(rtc_clock);
> +    s->tick_offset_vmstate = 0;
> +    s->alarm_next = 0;
> +    s->alarm_running = 0;
> +    s->irq_pending = 0;
> +    s->irq_enabled = 0;
> +}
> +
> +static void goldfish_rtc_realize(DeviceState *d, Error **errp)
> +{
> +    SysBusDevice *dev = SYS_BUS_DEVICE(d);
> +    GoldfishRTCState *s = GOLDFISH_RTC(d);
> +
> +    memory_region_init_io(&s->iomem, OBJECT(s), &goldfish_rtc_ops, s,
> +                          "goldfish_rtc", 0x1000);
> +    sysbus_init_mmio(dev, &s->iomem);
> +
> +    sysbus_init_irq(dev, &s->irq);
> +
> +    s->timer = timer_new_ns(rtc_clock, goldfish_rtc_interrupt, s);
> +}
> +
> +static void goldfish_rtc_class_init(ObjectClass *klass, void *data)
> +{
> +    DeviceClass *dc = DEVICE_CLASS(klass);
> +
> +    dc->realize = goldfish_rtc_realize;
> +    dc->reset = goldfish_rtc_reset;
> +    dc->vmsd = &goldfish_rtc_vmstate;
> +}
> +
> +static const TypeInfo goldfish_rtc_info = {
> +    .name          = TYPE_GOLDFISH_RTC,
> +    .parent        = TYPE_SYS_BUS_DEVICE,
> +    .instance_size = sizeof(GoldfishRTCState),
> +    .class_init    = goldfish_rtc_class_init,
> +};
> +
> +static void goldfish_rtc_register_types(void)
> +{
> +    type_register_static(&goldfish_rtc_info);
> +}
> +
> +type_init(goldfish_rtc_register_types)
> diff --git a/include/hw/timer/goldfish_rtc.h b/include/hw/timer/goldfish_
> rtc.h
> new file mode 100644
> index 0000000000..dfb6d70b86
> --- /dev/null
> +++ b/include/hw/timer/goldfish_rtc.h
> @@ -0,0 +1,46 @@
> +/*
> + * Goldfish virtual platform RTC
> + *
> + * Copyright (C) 2019 Western Digital Corporation or its affiliates.
> + *
> + * For more details on Google Goldfish virtual platform refer:
> + * https://android.googlesource.com/platform/external/qemu/+/
> master/docs/GOLDFISH-VIRTUAL-HARDWARE.TXT
> + *
> + * 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/>.
> + */
> +
> +#ifndef HW_TIMER_GOLDFISH_RTC_H
> +#define HW_TIMER_GOLDFISH_RTC_H
> +
> +#include "hw/sysbus.h"
> +
> +#define TYPE_GOLDFISH_RTC "goldfish_rtc"
> +#define GOLDFISH_RTC(obj) \
> +OBJECT_CHECK(GoldfishRTCState, (obj), TYPE_GOLDFISH_RTC)
> +
> +typedef struct GoldfishRTCState {
> +    SysBusDevice parent_obj;
> +
> +    MemoryRegion iomem;
> +    QEMUTimer *timer;
> +    qemu_irq irq;
> +
> +    uint64_t tick_offset;
> +    uint64_t tick_offset_vmstate;
> +    uint64_t alarm_next;
> +    uint32_t alarm_running;
> +    uint32_t irq_pending;
> +    uint32_t irq_enabled;
> +} GoldfishRTCState;
> +
> +#endif
> --
> 2.17.1
>
>

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^ permalink raw reply	[flat|nested] 11+ messages in thread

end of thread, other threads:[~2019-10-19  6:23 UTC | newest]

Thread overview: 11+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2019-10-15  8:35 [PATCH v3 0/2] RTC support for QEMU RISC-V virt machine Anup Patel
2019-10-15  8:35 ` [PATCH v3 1/2] hw: timer: Add Goldfish RTC device Anup Patel
2019-10-18 18:52   ` Palmer Dabbelt
2019-10-18 20:59   ` Alistair Francis
2019-10-19  4:21     ` Anup Patel
2019-10-18 21:15   ` Aleksandar Markovic
2019-10-19  4:33     ` Anup Patel
2019-10-19  6:21       ` Aleksandar Markovic
2019-10-15  8:35 ` [PATCH v3 2/2] riscv: virt: Use " Anup Patel
2019-10-18 18:52   ` Palmer Dabbelt
2019-10-18 21:00   ` Alistair Francis

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