zephyr/arch/arm64/core/xen/enlighten.c

72 lines
1.8 KiB
C

/*
* Copyright (c) 2021 EPAM Systems
*
* SPDX-License-Identifier: Apache-2.0
*/
#include <zephyr/arch/arm64/hypercall.h>
#include <zephyr/xen/events.h>
#include <zephyr/xen/generic.h>
#include <zephyr/xen/public/xen.h>
#include <zephyr/xen/public/memory.h>
#include <zephyr/device.h>
#include <zephyr/init.h>
#include <zephyr/kernel.h>
#include <zephyr/kernel/thread.h>
#include <zephyr/logging/log.h>
LOG_MODULE_REGISTER(xen_enlighten);
/*
* During Xen Enlighten initialization we need to have allocated memory page,
* where hypervisor shared_info will be mapped. k_aligned_alloc() is not
* available on PRE_KERNEL_1 stage, so we will use statically allocated buffer,
* which will be casted to 'struct shared_info'. It is needed to initialize Xen
* event channels as soon as possible after start.
*/
static uint8_t shared_info_buf[XEN_PAGE_SIZE] __aligned(XEN_PAGE_SIZE);
/* Remains NULL until mapping will be finished by Xen */
shared_info_t *HYPERVISOR_shared_info;
static int xen_map_shared_info(const shared_info_t *shared_page)
{
struct xen_add_to_physmap xatp;
xatp.domid = DOMID_SELF;
xatp.idx = 0;
xatp.space = XENMAPSPACE_shared_info;
xatp.gpfn = (((xen_pfn_t) shared_page) >> XEN_PAGE_SHIFT);
return HYPERVISOR_memory_op(XENMEM_add_to_physmap, &xatp);
}
static int xen_enlighten_init(const struct device *dev)
{
ARG_UNUSED(dev);
int ret = 0;
shared_info_t *info = (shared_info_t *) shared_info_buf;
ret = xen_map_shared_info(info);
if (ret) {
LOG_ERR("%s: failed to map for Xen shared page, ret = %d\n",
__func__, ret);
return ret;
}
/* Set value for globally visible pointer */
HYPERVISOR_shared_info = info;
ret = xen_events_init();
if (ret) {
LOG_ERR("%s: failed init Xen event channels, ret = %d\n",
__func__, ret);
return ret;
}
return 0;
}
SYS_INIT(xen_enlighten_init, PRE_KERNEL_1, CONFIG_KERNEL_INIT_PRIORITY_DEVICE);