qemu

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/*
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 * ARM SBSA Reference Platform Embedded Controller
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 *
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 * A device to allow PSCI running in the secure side of sbsa-ref machine
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 * to communicate platform power states to qemu.
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 *
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 * Copyright (c) 2020 Nuvia Inc
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 * Written by Graeme Gregory <graeme@nuviainc.com>
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 *
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 * SPDX-License-Identifier: GPL-2.0-or-later
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 */
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#include "qemu/osdep.h"
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#include "qemu/log.h"
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#include "hw/sysbus.h"
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#include "sysemu/runstate.h"
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typedef struct SECUREECState {
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    SysBusDevice parent_obj;
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    MemoryRegion iomem;
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} SECUREECState;
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#define TYPE_SBSA_SECURE_EC "sbsa-ec"
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OBJECT_DECLARE_SIMPLE_TYPE(SECUREECState, SBSA_SECURE_EC)
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enum sbsa_ec_powerstates {
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    SBSA_EC_CMD_POWEROFF = 0x01,
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    SBSA_EC_CMD_REBOOT = 0x02,
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};
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static uint64_t sbsa_ec_read(void *opaque, hwaddr offset, unsigned size)
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{
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    /* No use for this currently */
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    qemu_log_mask(LOG_GUEST_ERROR, "sbsa-ec: no readable registers");
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    return 0;
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}
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static void sbsa_ec_write(void *opaque, hwaddr offset,
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                          uint64_t value, unsigned size)
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{
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    if (offset == 0) { /* PSCI machine power command register */
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        switch (value) {
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        case SBSA_EC_CMD_POWEROFF:
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            qemu_system_shutdown_request(SHUTDOWN_CAUSE_GUEST_SHUTDOWN);
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            break;
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        case SBSA_EC_CMD_REBOOT:
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            qemu_system_reset_request(SHUTDOWN_CAUSE_GUEST_RESET);
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            break;
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        default:
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            qemu_log_mask(LOG_GUEST_ERROR,
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                          "sbsa-ec: unknown power command");
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        }
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    } else {
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        qemu_log_mask(LOG_GUEST_ERROR, "sbsa-ec: unknown EC register");
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    }
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}
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static const MemoryRegionOps sbsa_ec_ops = {
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    .read = sbsa_ec_read,
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    .write = sbsa_ec_write,
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    .endianness = DEVICE_NATIVE_ENDIAN,
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    .valid.min_access_size = 4,
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    .valid.max_access_size = 4,
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};
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static void sbsa_ec_init(Object *obj)
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{
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    SECUREECState *s = SBSA_SECURE_EC(obj);
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    SysBusDevice *dev = SYS_BUS_DEVICE(obj);
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    memory_region_init_io(&s->iomem, obj, &sbsa_ec_ops, s, "sbsa-ec",
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                          0x1000);
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    sysbus_init_mmio(dev, &s->iomem);
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}
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static void sbsa_ec_class_init(ObjectClass *klass, void *data)
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{
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    DeviceClass *dc = DEVICE_CLASS(klass);
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    /* No vmstate or reset required: device has no internal state */
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    dc->user_creatable = false;
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}
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static const TypeInfo sbsa_ec_info = {
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    .name          = TYPE_SBSA_SECURE_EC,
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    .parent        = TYPE_SYS_BUS_DEVICE,
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    .instance_size = sizeof(SECUREECState),
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    .instance_init = sbsa_ec_init,
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    .class_init    = sbsa_ec_class_init,
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};
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static void sbsa_ec_register_type(void)
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{
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    type_register_static(&sbsa_ec_info);
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}
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type_init(sbsa_ec_register_type);
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