116 lines
3.0 KiB
C
116 lines
3.0 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
|
|
/*
|
|
* Copyright (c) 2023-2024 Qualcomm Innovation Center, Inc. All rights reserved.
|
|
*/
|
|
|
|
#define pr_fmt(fmt) "gunyah: " fmt
|
|
|
|
#include <linux/gunyah.h>
|
|
#include <linux/module.h>
|
|
#include <linux/of_platform.h>
|
|
#include <linux/platform_device.h>
|
|
|
|
struct gunyah_info_desc {
|
|
__le16 id;
|
|
__le16 owner;
|
|
__le32 size;
|
|
__le32 offset;
|
|
#define INFO_DESC_VALID BIT(31)
|
|
__le32 flags;
|
|
};
|
|
|
|
static void *info_area;
|
|
|
|
void *gunyah_get_info(u16 owner, u16 id, size_t *size)
|
|
{
|
|
struct gunyah_info_desc *desc = info_area;
|
|
__le16 le_owner = cpu_to_le16(owner);
|
|
__le16 le_id = cpu_to_le16(id);
|
|
|
|
if (!desc)
|
|
return ERR_PTR(-ENOENT);
|
|
|
|
for (desc = info_area; le32_to_cpu(desc->offset); desc++) {
|
|
if (!(le32_to_cpu(desc->flags) & INFO_DESC_VALID))
|
|
continue;
|
|
mb();
|
|
if (le_owner == desc->owner && le_id == desc->id) {
|
|
if (size)
|
|
*size = le32_to_cpu(desc->size);
|
|
return info_area + le32_to_cpu(desc->offset);
|
|
}
|
|
}
|
|
return ERR_PTR(-ENOENT);
|
|
}
|
|
EXPORT_SYMBOL_GPL(gunyah_get_info);
|
|
|
|
/**
|
|
* gunyah_map_addrspace_info_area - Map the addrspace info area
|
|
*
|
|
* Maps the hypervisor-provided addrspace info area into kernel space.
|
|
* Typically used once during the initialization and after hibernation
|
|
* restore (PM_POST_HIBERNATION) or in other scenarios where the info area
|
|
* needs to be re-initialized so as to establish the communincation with
|
|
* the resource manager.
|
|
*/
|
|
int gunyah_map_addrspace_info_area(void)
|
|
{
|
|
unsigned long info_ipa, info_size;
|
|
enum gunyah_error gh_error;
|
|
|
|
gh_error = gunyah_hypercall_addrspace_find_info_area(&info_ipa, &info_size);
|
|
/* ignore errors for compatibility with gh without info_area support */
|
|
if (gh_error != GUNYAH_ERROR_OK)
|
|
return 0;
|
|
|
|
info_area = memremap(info_ipa, info_size, MEMREMAP_WB);
|
|
if (!info_area) {
|
|
pr_err("Failed to map addrspace info area\n");
|
|
return -ENOMEM;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(gunyah_map_addrspace_info_area);
|
|
|
|
/**
|
|
* gunyah_unmap_addrspace_info_area - Unmap the addrspace info area
|
|
*
|
|
* Unmaps the previously mapped addrspace info area. Commonly used
|
|
* before hibernation (PM_HIBERNATION_PREPARE) or when the mapping
|
|
* is no longer needed.
|
|
*/
|
|
void gunyah_unmap_addrspace_info_area(void)
|
|
{
|
|
memunmap(info_area);
|
|
info_area = NULL;
|
|
}
|
|
EXPORT_SYMBOL_GPL(gunyah_unmap_addrspace_info_area);
|
|
|
|
static int __init gunyah_init(void)
|
|
{
|
|
struct gunyah_hypercall_hyp_identify_resp gunyah_api;
|
|
|
|
if (!arch_is_gunyah_guest())
|
|
return -ENODEV;
|
|
|
|
gunyah_hypercall_hyp_identify(&gunyah_api);
|
|
|
|
pr_info("Running under Gunyah hypervisor %llx/v%u\n",
|
|
FIELD_GET(GUNYAH_API_INFO_VARIANT_MASK, gunyah_api.api_info),
|
|
gunyah_api_version(&gunyah_api));
|
|
|
|
/* Might move this out to individual drivers if there's ever an API version bump */
|
|
if (gunyah_api_version(&gunyah_api) != GUNYAH_API_V1) {
|
|
pr_info("Unsupported Gunyah version: %u\n",
|
|
gunyah_api_version(&gunyah_api));
|
|
return -ENODEV;
|
|
}
|
|
|
|
return gunyah_map_addrspace_info_area();
|
|
}
|
|
core_initcall(gunyah_init);
|
|
|
|
MODULE_LICENSE("GPL");
|
|
MODULE_DESCRIPTION("Gunyah Driver");
|