Re: [Qemu-devel] [PATCH v3 14/30] i.MX: Add code to emulate i.MX2 watchdog IP block

[Andrey Smirnov]

On Tue, Nov 21, 2017 at 10:10 AM, Peter Maydell
<address@hidden> wrote:
> On 6 November 2017 at 15:47, Andrey Smirnov <address@hidden> wrote:
>> Add enough code to emulate i.MX2 watchdog IP block so it would be
>> possible to reboot the machine running Linux Guest.
>>
>> Cc: Peter Maydell <address@hidden>
>> Cc: Jason Wang <address@hidden>
>> Cc: Philippe Mathieu-Daudé <address@hidden>
>> Cc: address@hidden
>> Cc: address@hidden
>> Cc: address@hidden
>> Signed-off-by: Andrey Smirnov <address@hidden>
>> ---
>>  hw/misc/Makefile.objs      |  1 +
>>  hw/misc/imx2_wdt.c         | 88 
>> ++++++++++++++++++++++++++++++++++++++++++++++
>>  include/hw/misc/imx2_wdt.h | 34 ++++++++++++++++++
>>  3 files changed, 123 insertions(+)
>>  create mode 100644 hw/misc/imx2_wdt.c
>>  create mode 100644 include/hw/misc/imx2_wdt.h
>>
>> diff --git a/hw/misc/Makefile.objs b/hw/misc/Makefile.objs
>> index ac1be05a03..c393a93456 100644
>> --- a/hw/misc/Makefile.objs
>> +++ b/hw/misc/Makefile.objs
>> @@ -35,6 +35,7 @@ obj-$(CONFIG_IMX) += imx25_ccm.o
>>  obj-$(CONFIG_IMX) += imx6_ccm.o
>>  obj-$(CONFIG_IMX) += imx6_src.o
>>  obj-$(CONFIG_IMX) += imx7_ccm.o
>> +obj-$(CONFIG_IMX) += imx2_wdt.o
>>  obj-$(CONFIG_MILKYMIST) += milkymist-hpdmc.o
>>  obj-$(CONFIG_MILKYMIST) += milkymist-pfpu.o
>>  obj-$(CONFIG_MAINSTONE) += mst_fpga.o
>> diff --git a/hw/misc/imx2_wdt.c b/hw/misc/imx2_wdt.c
>> new file mode 100644
>> index 0000000000..3a1c33aa51
>> --- /dev/null
>> +++ b/hw/misc/imx2_wdt.c
>> @@ -0,0 +1,88 @@
>> +/*
>> + * Copyright (c) 2017, Impinj, Inc.
>> + *
>> + * i.MX2 Watchdog IP block
>> + *
>> + * Author: Andrey Smirnov <address@hidden>
>> + *
>> + * This work is licensed under the terms of the GNU GPL, version 2 or later.
>> + * See the COPYING file in the top-level directory.
>> + */
>> +
>> +#include "qemu/osdep.h"
>> +#include "sysemu/watchdog.h"
>> +
>> +#include "hw/misc/imx2_wdt.h"
>> +
>> +#define IMX2_WDT_WCR_WDA    BIT(5)      /* -> External Reset WDOG_B */
>> +#define IMX2_WDT_WCR_SRS    BIT(4)      /* -> Software Reset Signal */
>> +
>> +static uint64_t imx2_wdt_read(void *opaque, hwaddr addr,
>> +                              unsigned int size)
>> +{
>> +    return 0;
>> +}
>> +
>> +static void imx2_wdt_write(void *opaque, hwaddr addr,
>> +                           uint64_t value, unsigned int size)
>> +{
>> +    if (addr == IMX2_WDT_WCR &&
>> +        (value & (IMX2_WDT_WCR_WDA | IMX2_WDT_WCR_SRS))) {
>> +        watchdog_perform_action();
>> +    }
>> +}
>> +
>> +static const MemoryRegionOps imx2_wdt_ops = {
>> +    .read  = imx2_wdt_read,
>> +    .write = imx2_wdt_write,
>> +    .endianness = DEVICE_NATIVE_ENDIAN,
>> +    .impl = {
>> +        /*
>> +         * Our device would not work correctly if the guest was doing
>> +         * unaligned access. This might not be a limitation on the
>> +         * real device but in practice there is no reason for a guest
>> +         * to access this device unaligned.
>> +         */
>> +        .min_access_size = 4,
>> +        .max_access_size = 4,
>> +        .unaligned = false,
>> +    },
>> +};
>> +
>> +static void imx2_wdt_realize(DeviceState *dev, Error **errp)
>> +{
>> +    IMX2WdtState *s = IMX2_WDT(dev);
>> +
>> +    memory_region_init_io(&s->mmio, OBJECT(dev),
>> +                          &imx2_wdt_ops, s,
>> +                          TYPE_IMX2_WDT".mmio",
>> +                          IMX2_WDT_REG_NUM * sizeof(uint16_t));
>> +    sysbus_init_mmio(SYS_BUS_DEVICE(dev), &s->mmio);
>> +}
>> +
>> +static void imx2_wdt_class_init(ObjectClass *klass, void *data)
>> +{
>> +    DeviceClass *dc = DEVICE_CLASS(klass);
>> +
>> +    dc->realize = imx2_wdt_realize;
>> +    set_bit(DEVICE_CATEGORY_MISC, dc->categories);
>> +}
>> +
>> +static const TypeInfo imx2_wdt_info = {
>> +    .name          = TYPE_IMX2_WDT,
>> +    .parent        = TYPE_SYS_BUS_DEVICE,
>> +    .instance_size = sizeof(IMX2WdtState),
>> +    .class_init    = imx2_wdt_class_init,
>> +};
>> +
>> +static WatchdogTimerModel model = {
>> +    .wdt_name = "imx2-watchdog",
>> +    .wdt_description = "i.MX2 Watchdog",
>> +};
>> +
>> +static void imx2_wdt_register_type(void)
>> +{
>> +    watchdog_add_model(&model);
>> +    type_register_static(&imx2_wdt_info);
>> +}
>> +type_init(imx2_wdt_register_type)
>> diff --git a/include/hw/misc/imx2_wdt.h b/include/hw/misc/imx2_wdt.h
>> new file mode 100644
>> index 0000000000..e67ac6939d
>> --- /dev/null
>> +++ b/include/hw/misc/imx2_wdt.h
>> @@ -0,0 +1,34 @@
>> +/*
>> + * Copyright (c) 2017, Impinj, Inc.
>> + *
>> + * i.MX2 Watchdog IP block
>> + *
>> + * Author: Andrey Smirnov <address@hidden>
>> + *
>> + * This work is licensed under the terms of the GNU GPL, version 2 or later.
>> + * See the COPYING file in the top-level directory.
>> + */
>> +
>> +#ifndef IMX2_WDT_H
>> +#define IMX2_WDT_H
>> +
>> +#include "qemu/bitops.h"
>> +#include "hw/sysbus.h"
>
> The bitops.h include should be in the .c file, not here.
>

Will fix in v4.

Thanks,
Andrey Smirnov