freebsd-dev/usr.sbin/bhyve/qemu_fwcfg.c
Corvin Köhne 158adced65
bhyve: save softc of ACPI devices
This will be useful for writing device specific ACPI tables or DSDT
methods.

Reviewed by:		markj
MFC after:		1 week
Sponsored by:		Beckhoff Automation GmbH & Co. KG
Differential Revision:	https://reviews.freebsd.org/D39322
2023-04-13 08:00:09 +02:00

471 lines
12 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright (c) 2021 Beckhoff Automation GmbH & Co. KG
* Author: Corvin Köhne <c.koehne@beckhoff.com>
*/
#include <sys/param.h>
#include <sys/endian.h>
#include <machine/vmm.h>
#include <err.h>
#include <errno.h>
#include <stdlib.h>
#include <string.h>
#include "acpi_device.h"
#include "bhyverun.h"
#include "inout.h"
#include "pci_lpc.h"
#include "qemu_fwcfg.h"
#define QEMU_FWCFG_ACPI_DEVICE_NAME "FWCF"
#define QEMU_FWCFG_ACPI_HARDWARE_ID "QEMU0002"
#define QEMU_FWCFG_SELECTOR_PORT_NUMBER 0x510
#define QEMU_FWCFG_SELECTOR_PORT_SIZE 1
#define QEMU_FWCFG_SELECTOR_PORT_FLAGS IOPORT_F_INOUT
#define QEMU_FWCFG_DATA_PORT_NUMBER 0x511
#define QEMU_FWCFG_DATA_PORT_SIZE 1
#define QEMU_FWCFG_DATA_PORT_FLAGS \
IOPORT_F_INOUT /* QEMU v2.4+ ignores writes */
#define QEMU_FWCFG_ARCHITECTURE_MASK 0x0001
#define QEMU_FWCFG_INDEX_MASK 0x3FFF
#define QEMU_FWCFG_SELECT_READ 0
#define QEMU_FWCFG_SELECT_WRITE 1
#define QEMU_FWCFG_ARCHITECTURE_GENERIC 0
#define QEMU_FWCFG_ARCHITECTURE_SPECIFIC 1
#define QEMU_FWCFG_INDEX_SIGNATURE 0x00
#define QEMU_FWCFG_INDEX_ID 0x01
#define QEMU_FWCFG_INDEX_NB_CPUS 0x05
#define QEMU_FWCFG_INDEX_MAX_CPUS 0x0F
#define QEMU_FWCFG_INDEX_FILE_DIR 0x19
#define QEMU_FWCFG_FIRST_FILE_INDEX 0x20
#define QEMU_FWCFG_MIN_FILES 10
#pragma pack(1)
union qemu_fwcfg_selector {
struct {
uint16_t index : 14;
uint16_t writeable : 1;
uint16_t architecture : 1;
};
uint16_t bits;
};
struct qemu_fwcfg_signature {
uint8_t signature[4];
};
struct qemu_fwcfg_id {
uint32_t interface : 1; /* always set */
uint32_t DMA : 1;
uint32_t reserved : 30;
};
struct qemu_fwcfg_file {
uint32_t be_size;
uint16_t be_selector;
uint16_t reserved;
uint8_t name[QEMU_FWCFG_MAX_NAME];
};
struct qemu_fwcfg_directory {
uint32_t be_count;
struct qemu_fwcfg_file files[0];
};
#pragma pack()
struct qemu_fwcfg_softc {
struct acpi_device *acpi_dev;
uint32_t data_offset;
union qemu_fwcfg_selector selector;
struct qemu_fwcfg_item items[QEMU_FWCFG_MAX_ARCHS]
[QEMU_FWCFG_MAX_ENTRIES];
struct qemu_fwcfg_directory *directory;
};
static struct qemu_fwcfg_softc fwcfg_sc;
static int
qemu_fwcfg_selector_port_handler(struct vmctx *const ctx __unused, const int in,
const int port __unused, const int bytes, uint32_t *const eax,
void *const arg __unused)
{
if (bytes != sizeof(uint16_t)) {
warnx("%s: invalid size (%d) of IO port access", __func__,
bytes);
return (-1);
}
if (in) {
*eax = htole16(fwcfg_sc.selector.bits);
return (0);
}
fwcfg_sc.data_offset = 0;
fwcfg_sc.selector.bits = le16toh(*eax);
return (0);
}
static int
qemu_fwcfg_data_port_handler(struct vmctx *const ctx __unused, const int in,
const int port __unused, const int bytes, uint32_t *const eax,
void *const arg __unused)
{
if (bytes != sizeof(uint8_t)) {
warnx("%s: invalid size (%d) of IO port access", __func__,
bytes);
return (-1);
}
if (!in) {
warnx("%s: Writes to qemu fwcfg data port aren't allowed",
__func__);
return (-1);
}
/* get fwcfg item */
struct qemu_fwcfg_item *const item =
&fwcfg_sc.items[fwcfg_sc.selector.architecture]
[fwcfg_sc.selector.index];
if (item->data == NULL) {
warnx(
"%s: qemu fwcfg item doesn't exist (architecture %s index 0x%x)",
__func__,
fwcfg_sc.selector.architecture ? "specific" : "generic",
fwcfg_sc.selector.index);
*eax = 0x00;
return (0);
} else if (fwcfg_sc.data_offset >= item->size) {
warnx(
"%s: qemu fwcfg item read exceeds size (architecture %s index 0x%x size 0x%x offset 0x%x)",
__func__,
fwcfg_sc.selector.architecture ? "specific" : "generic",
fwcfg_sc.selector.index, item->size, fwcfg_sc.data_offset);
*eax = 0x00;
return (0);
}
/* return item data */
*eax = item->data[fwcfg_sc.data_offset];
fwcfg_sc.data_offset++;
return (0);
}
static int
qemu_fwcfg_add_item(const uint16_t architecture, const uint16_t index,
const uint32_t size, void *const data)
{
/* truncate architecture and index to their desired size */
const uint16_t arch = architecture & QEMU_FWCFG_ARCHITECTURE_MASK;
const uint16_t idx = index & QEMU_FWCFG_INDEX_MASK;
/* get pointer to item specified by selector */
struct qemu_fwcfg_item *const fwcfg_item = &fwcfg_sc.items[arch][idx];
/* check if item is already used */
if (fwcfg_item->data != NULL) {
warnx("%s: qemu fwcfg item exists (architecture %s index 0x%x)",
__func__, arch ? "specific" : "generic", idx);
return (EEXIST);
}
/* save data of the item */
fwcfg_item->size = size;
fwcfg_item->data = data;
return (0);
}
static int
qemu_fwcfg_add_item_file_dir(void)
{
const size_t size = sizeof(struct qemu_fwcfg_directory) +
QEMU_FWCFG_MIN_FILES * sizeof(struct qemu_fwcfg_file);
struct qemu_fwcfg_directory *const fwcfg_directory = calloc(1, size);
if (fwcfg_directory == NULL) {
return (ENOMEM);
}
fwcfg_sc.directory = fwcfg_directory;
return (qemu_fwcfg_add_item(QEMU_FWCFG_ARCHITECTURE_GENERIC,
QEMU_FWCFG_INDEX_FILE_DIR, sizeof(struct qemu_fwcfg_directory),
(uint8_t *)fwcfg_sc.directory));
}
static int
qemu_fwcfg_add_item_id(void)
{
struct qemu_fwcfg_id *const fwcfg_id = calloc(1,
sizeof(struct qemu_fwcfg_id));
if (fwcfg_id == NULL) {
return (ENOMEM);
}
fwcfg_id->interface = 1;
fwcfg_id->DMA = 0;
uint32_t *const le_fwcfg_id_ptr = (uint32_t *)fwcfg_id;
*le_fwcfg_id_ptr = htole32(*le_fwcfg_id_ptr);
return (qemu_fwcfg_add_item(QEMU_FWCFG_ARCHITECTURE_GENERIC,
QEMU_FWCFG_INDEX_ID, sizeof(struct qemu_fwcfg_id),
(uint8_t *)fwcfg_id));
}
static int
qemu_fwcfg_add_item_max_cpus(void)
{
uint16_t *fwcfg_max_cpus = calloc(1, sizeof(uint16_t));
if (fwcfg_max_cpus == NULL) {
return (ENOMEM);
}
/*
* We don't support cpu hotplug yet. For that reason, use guest_ncpus instead
* of maxcpus.
*/
*fwcfg_max_cpus = htole16(guest_ncpus);
return (qemu_fwcfg_add_item(QEMU_FWCFG_ARCHITECTURE_GENERIC,
QEMU_FWCFG_INDEX_MAX_CPUS, sizeof(uint16_t), fwcfg_max_cpus));
}
static int
qemu_fwcfg_add_item_nb_cpus(void)
{
uint16_t *fwcfg_max_cpus = calloc(1, sizeof(uint16_t));
if (fwcfg_max_cpus == NULL) {
return (ENOMEM);
}
*fwcfg_max_cpus = htole16(guest_ncpus);
return (qemu_fwcfg_add_item(QEMU_FWCFG_ARCHITECTURE_GENERIC,
QEMU_FWCFG_INDEX_NB_CPUS, sizeof(uint16_t), fwcfg_max_cpus));
}
static int
qemu_fwcfg_add_item_signature(void)
{
struct qemu_fwcfg_signature *const fwcfg_signature = calloc(1,
sizeof(struct qemu_fwcfg_signature));
if (fwcfg_signature == NULL) {
return (ENOMEM);
}
fwcfg_signature->signature[0] = 'Q';
fwcfg_signature->signature[1] = 'E';
fwcfg_signature->signature[2] = 'M';
fwcfg_signature->signature[3] = 'U';
return (qemu_fwcfg_add_item(QEMU_FWCFG_ARCHITECTURE_GENERIC,
QEMU_FWCFG_INDEX_SIGNATURE, sizeof(struct qemu_fwcfg_signature),
(uint8_t *)fwcfg_signature));
}
static int
qemu_fwcfg_register_port(const char *const name, const int port, const int size,
const int flags, const inout_func_t handler)
{
struct inout_port iop;
bzero(&iop, sizeof(iop));
iop.name = name;
iop.port = port;
iop.size = size;
iop.flags = flags;
iop.handler = handler;
return (register_inout(&iop));
}
int
qemu_fwcfg_add_file(const char *name, const uint32_t size, void *const data)
{
if (strlen(name) >= QEMU_FWCFG_MAX_NAME)
return (EINVAL);
/*
* QEMU specifies count as big endian.
* Convert it to host endian to work with it.
*/
const uint32_t count = be32toh(fwcfg_sc.directory->be_count) + 1;
/* add file to items list */
const uint32_t index = QEMU_FWCFG_FIRST_FILE_INDEX + count - 1;
const int error = qemu_fwcfg_add_item(QEMU_FWCFG_ARCHITECTURE_GENERIC,
index, size, data);
if (error != 0) {
return (error);
}
/*
* files should be sorted alphabetical, get index for new file
*/
uint32_t file_index;
for (file_index = 0; file_index < count - 1; ++file_index) {
if (strcmp(name, fwcfg_sc.directory->files[file_index].name) <
0)
break;
}
if (count > QEMU_FWCFG_MIN_FILES) {
/* alloc new file directory */
const uint64_t new_size = sizeof(struct qemu_fwcfg_directory) +
count * sizeof(struct qemu_fwcfg_file);
struct qemu_fwcfg_directory *const new_directory = calloc(1,
new_size);
if (new_directory == NULL) {
warnx(
"%s: Unable to allocate a new qemu fwcfg files directory (count %d)",
__func__, count);
return (ENOMEM);
}
/* copy files below file_index to new directory */
memcpy(new_directory->files, fwcfg_sc.directory->files,
file_index * sizeof(struct qemu_fwcfg_file));
/* copy files above file_index to directory */
memcpy(&new_directory->files[file_index + 1],
&fwcfg_sc.directory->files[file_index],
(count - file_index) * sizeof(struct qemu_fwcfg_file));
/* free old directory */
free(fwcfg_sc.directory);
/* set directory pointer to new directory */
fwcfg_sc.directory = new_directory;
/* adjust directory pointer */
fwcfg_sc.items[0][QEMU_FWCFG_INDEX_FILE_DIR].data =
(uint8_t *)fwcfg_sc.directory;
} else {
/* shift files behind file_index */
for (uint32_t i = QEMU_FWCFG_MIN_FILES - 1; i > file_index;
--i) {
memcpy(&fwcfg_sc.directory->files[i],
&fwcfg_sc.directory->files[i - 1],
sizeof(struct qemu_fwcfg_file));
}
}
/*
* QEMU specifies count, size and index as big endian.
* Save these values in big endian to simplify guest reads of these
* values.
*/
fwcfg_sc.directory->be_count = htobe32(count);
fwcfg_sc.directory->files[file_index].be_size = htobe32(size);
fwcfg_sc.directory->files[file_index].be_selector = htobe16(index);
strcpy(fwcfg_sc.directory->files[file_index].name, name);
/* set new size for the fwcfg_file_directory */
fwcfg_sc.items[0][QEMU_FWCFG_INDEX_FILE_DIR].size =
sizeof(struct qemu_fwcfg_directory) +
count * sizeof(struct qemu_fwcfg_file);
return (0);
}
static const struct acpi_device_emul qemu_fwcfg_acpi_device_emul = {
.name = QEMU_FWCFG_ACPI_DEVICE_NAME,
.hid = QEMU_FWCFG_ACPI_HARDWARE_ID,
};
int
qemu_fwcfg_init(struct vmctx *const ctx)
{
int error;
/*
* Bhyve supports fwctl (bhyve) and fwcfg (qemu) as firmware interfaces.
* Both are using the same ports. So, it's not possible to provide both
* interfaces at the same time to the guest. Therefore, only create acpi
* tables and register io ports for fwcfg, if it's used.
*/
if (strcmp(lpc_fwcfg(), "qemu") == 0) {
error = acpi_device_create(&fwcfg_sc.acpi_dev, &fwcfg_sc, ctx,
&qemu_fwcfg_acpi_device_emul);
if (error) {
warnx("%s: failed to create ACPI device for QEMU FwCfg",
__func__);
goto done;
}
error = acpi_device_add_res_fixed_ioport(fwcfg_sc.acpi_dev,
QEMU_FWCFG_SELECTOR_PORT_NUMBER, 2);
if (error) {
warnx("%s: failed to add fixed IO port for QEMU FwCfg",
__func__);
goto done;
}
/* add handlers for fwcfg ports */
if ((error = qemu_fwcfg_register_port("qemu_fwcfg_selector",
QEMU_FWCFG_SELECTOR_PORT_NUMBER,
QEMU_FWCFG_SELECTOR_PORT_SIZE,
QEMU_FWCFG_SELECTOR_PORT_FLAGS,
qemu_fwcfg_selector_port_handler)) != 0) {
warnx(
"%s: Unable to register qemu fwcfg selector port 0x%x",
__func__, QEMU_FWCFG_SELECTOR_PORT_NUMBER);
goto done;
}
if ((error = qemu_fwcfg_register_port("qemu_fwcfg_data",
QEMU_FWCFG_DATA_PORT_NUMBER, QEMU_FWCFG_DATA_PORT_SIZE,
QEMU_FWCFG_DATA_PORT_FLAGS,
qemu_fwcfg_data_port_handler)) != 0) {
warnx(
"%s: Unable to register qemu fwcfg data port 0x%x",
__func__, QEMU_FWCFG_DATA_PORT_NUMBER);
goto done;
}
}
/* add common fwcfg items */
if ((error = qemu_fwcfg_add_item_signature()) != 0) {
warnx("%s: Unable to add signature item", __func__);
goto done;
}
if ((error = qemu_fwcfg_add_item_id()) != 0) {
warnx("%s: Unable to add id item", __func__);
goto done;
}
if ((error = qemu_fwcfg_add_item_nb_cpus()) != 0) {
warnx("%s: Unable to add nb_cpus item", __func__);
goto done;
}
if ((error = qemu_fwcfg_add_item_max_cpus()) != 0) {
warnx("%s: Unable to add max_cpus item", __func__);
goto done;
}
if ((error = qemu_fwcfg_add_item_file_dir()) != 0) {
warnx("%s: Unable to add file_dir item", __func__);
goto done;
}
done:
if (error) {
acpi_device_destroy(fwcfg_sc.acpi_dev);
}
return (error);
}