blob: c0d338db6b525a95ca4e3d6f1b733d67486c6c51 [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0
/*
* BOOTROM Greybus driver.
*
* Copyright 2016 Google Inc.
* Copyright 2016 Linaro Ltd.
*/
#include <linux/firmware.h>
#include <linux/jiffies.h>
#include <linux/mutex.h>
#include <linux/workqueue.h>
#include <linux/greybus.h>
#include "firmware.h"
/* Timeout, in jiffies, within which the next request must be received */
#define NEXT_REQ_TIMEOUT_MS 1000
/*
* FIXME: Reduce this timeout once svc core handles parallel processing of
* events from the SVC, which are handled sequentially today.
*/
#define MODE_SWITCH_TIMEOUT_MS 10000
enum next_request_type {
NEXT_REQ_FIRMWARE_SIZE,
NEXT_REQ_GET_FIRMWARE,
NEXT_REQ_READY_TO_BOOT,
NEXT_REQ_MODE_SWITCH,
};
struct gb_bootrom {
struct gb_connection *connection;
const struct firmware *fw;
u8 protocol_major;
u8 protocol_minor;
enum next_request_type next_request;
struct delayed_work dwork;
struct mutex mutex; /* Protects bootrom->fw */
};
static void free_firmware(struct gb_bootrom *bootrom)
{
if (!bootrom->fw)
return;
release_firmware(bootrom->fw);
bootrom->fw = NULL;
}
static void gb_bootrom_timedout(struct work_struct *work)
{
struct delayed_work *dwork = to_delayed_work(work);
struct gb_bootrom *bootrom = container_of(dwork,
struct gb_bootrom, dwork);
struct device *dev = &bootrom->connection->bundle->dev;
const char *reason;
switch (bootrom->next_request) {
case NEXT_REQ_FIRMWARE_SIZE:
reason = "Firmware Size Request";
break;
case NEXT_REQ_GET_FIRMWARE:
reason = "Get Firmware Request";
break;
case NEXT_REQ_READY_TO_BOOT:
reason = "Ready to Boot Request";
break;
case NEXT_REQ_MODE_SWITCH:
reason = "Interface Mode Switch";
break;
default:
reason = NULL;
dev_err(dev, "Invalid next-request: %u", bootrom->next_request);
break;
}
dev_err(dev, "Timed out waiting for %s from the Module\n", reason);
mutex_lock(&bootrom->mutex);
free_firmware(bootrom);
mutex_unlock(&bootrom->mutex);
/* TODO: Power-off Module ? */
}
static void gb_bootrom_set_timeout(struct gb_bootrom *bootrom,
enum next_request_type next,
unsigned long timeout)
{
bootrom->next_request = next;
schedule_delayed_work(&bootrom->dwork, msecs_to_jiffies(timeout));
}
static void gb_bootrom_cancel_timeout(struct gb_bootrom *bootrom)
{
cancel_delayed_work_sync(&bootrom->dwork);
}
/*
* The es2 chip doesn't have VID/PID programmed into the hardware and we need to
* hack that up to distinguish different modules and their firmware blobs.
*
* This fetches VID/PID (over bootrom protocol) for es2 chip only, when VID/PID
* already sent during hotplug are 0.
*
* Otherwise, we keep intf->vendor_id/product_id same as what's passed
* during hotplug.
*/
static void bootrom_es2_fixup_vid_pid(struct gb_bootrom *bootrom)
{
struct gb_bootrom_get_vid_pid_response response;
struct gb_connection *connection = bootrom->connection;
struct gb_interface *intf = connection->bundle->intf;
int ret;
if (!(intf->quirks & GB_INTERFACE_QUIRK_NO_GMP_IDS))
return;
ret = gb_operation_sync(connection, GB_BOOTROM_TYPE_GET_VID_PID,
NULL, 0, &response, sizeof(response));
if (ret) {
dev_err(&connection->bundle->dev,
"Bootrom get vid/pid operation failed (%d)\n", ret);
return;
}
/*
* NOTE: This is hacked, so that the same values of VID/PID can be used
* by next firmware level as well. The uevent for bootrom will still
* have VID/PID as 0, though after this point the sysfs files will start
* showing the updated values. But yeah, that's a bit racy as the same
* sysfs files would be showing 0 before this point.
*/
intf->vendor_id = le32_to_cpu(response.vendor_id);
intf->product_id = le32_to_cpu(response.product_id);
dev_dbg(&connection->bundle->dev, "Bootrom got vid (0x%x)/pid (0x%x)\n",
intf->vendor_id, intf->product_id);
}
/* This returns path of the firmware blob on the disk */
static int find_firmware(struct gb_bootrom *bootrom, u8 stage)
{
struct gb_connection *connection = bootrom->connection;
struct gb_interface *intf = connection->bundle->intf;
char firmware_name[49];
int rc;
/* Already have a firmware, free it */
free_firmware(bootrom);
/* Bootrom protocol is only supported for loading Stage 2 firmware */
if (stage != 2) {
dev_err(&connection->bundle->dev, "Invalid boot stage: %u\n",
stage);
return -EINVAL;
}
/*
* Create firmware name
*
* XXX Name it properly..
*/
snprintf(firmware_name, sizeof(firmware_name),
FW_NAME_PREFIX "%08x_%08x_%08x_%08x_s2l.tftf",
intf->ddbl1_manufacturer_id, intf->ddbl1_product_id,
intf->vendor_id, intf->product_id);
// FIXME:
// Turn to dev_dbg later after everyone has valid bootloaders with good
// ids, but leave this as dev_info for now to make it easier to track
// down "empty" vid/pid modules.
dev_info(&connection->bundle->dev, "Firmware file '%s' requested\n",
firmware_name);
rc = request_firmware(&bootrom->fw, firmware_name,
&connection->bundle->dev);
if (rc) {
dev_err(&connection->bundle->dev,
"failed to find %s firmware (%d)\n", firmware_name, rc);
}
return rc;
}
static int gb_bootrom_firmware_size_request(struct gb_operation *op)
{
struct gb_bootrom *bootrom = gb_connection_get_data(op->connection);
struct gb_bootrom_firmware_size_request *size_request =
op->request->payload;
struct gb_bootrom_firmware_size_response *size_response;
struct device *dev = &op->connection->bundle->dev;
int ret;
/* Disable timeouts */
gb_bootrom_cancel_timeout(bootrom);
if (op->request->payload_size != sizeof(*size_request)) {
dev_err(dev, "%s: illegal size of firmware size request (%zu != %zu)\n",
__func__, op->request->payload_size,
sizeof(*size_request));
ret = -EINVAL;
goto queue_work;
}
mutex_lock(&bootrom->mutex);
ret = find_firmware(bootrom, size_request->stage);
if (ret)
goto unlock;
if (!gb_operation_response_alloc(op, sizeof(*size_response),
GFP_KERNEL)) {
dev_err(dev, "%s: error allocating response\n", __func__);
free_firmware(bootrom);
ret = -ENOMEM;
goto unlock;
}
size_response = op->response->payload;
size_response->size = cpu_to_le32(bootrom->fw->size);
dev_dbg(dev, "%s: firmware size %d bytes\n",
__func__, size_response->size);
unlock:
mutex_unlock(&bootrom->mutex);
queue_work:
if (!ret) {
/* Refresh timeout */
gb_bootrom_set_timeout(bootrom, NEXT_REQ_GET_FIRMWARE,
NEXT_REQ_TIMEOUT_MS);
}
return ret;
}
static int gb_bootrom_get_firmware(struct gb_operation *op)
{
struct gb_bootrom *bootrom = gb_connection_get_data(op->connection);
const struct firmware *fw;
struct gb_bootrom_get_firmware_request *firmware_request;
struct device *dev = &op->connection->bundle->dev;
unsigned int offset, size;
enum next_request_type next_request;
u8 *firmware_response;
int ret = 0;
/* Disable timeouts */
gb_bootrom_cancel_timeout(bootrom);
if (op->request->payload_size != sizeof(*firmware_request)) {
dev_err(dev, "%s: Illegal size of get firmware request (%zu %zu)\n",
__func__, op->request->payload_size,
sizeof(*firmware_request));
ret = -EINVAL;
goto queue_work;
}
mutex_lock(&bootrom->mutex);
fw = bootrom->fw;
if (!fw) {
dev_err(dev, "%s: firmware not available\n", __func__);
ret = -EINVAL;
goto unlock;
}
firmware_request = op->request->payload;
offset = le32_to_cpu(firmware_request->offset);
size = le32_to_cpu(firmware_request->size);
if (offset >= fw->size || size > fw->size - offset) {
dev_warn(dev, "bad firmware request (offs = %u, size = %u)\n",
offset, size);
ret = -EINVAL;
goto unlock;
}
/* gb_bootrom_get_firmware_response contains only a byte array */
if (!gb_operation_response_alloc(op, size, GFP_KERNEL)) {
dev_err(dev, "%s: error allocating response\n", __func__);
ret = -ENOMEM;
goto unlock;
}
firmware_response = op->response->payload;
memcpy(firmware_response, fw->data + offset, size);
dev_dbg(dev, "responding with firmware (offs = %u, size = %u)\n",
offset, size);
unlock:
mutex_unlock(&bootrom->mutex);
queue_work:
/* Refresh timeout */
if (!ret && (offset + size == fw->size))
next_request = NEXT_REQ_READY_TO_BOOT;
else
next_request = NEXT_REQ_GET_FIRMWARE;
gb_bootrom_set_timeout(bootrom, next_request, NEXT_REQ_TIMEOUT_MS);
return ret;
}
static int gb_bootrom_ready_to_boot(struct gb_operation *op)
{
struct gb_connection *connection = op->connection;
struct gb_bootrom *bootrom = gb_connection_get_data(connection);
struct gb_bootrom_ready_to_boot_request *rtb_request;
struct device *dev = &connection->bundle->dev;
u8 status;
int ret = 0;
/* Disable timeouts */
gb_bootrom_cancel_timeout(bootrom);
if (op->request->payload_size != sizeof(*rtb_request)) {
dev_err(dev, "%s: Illegal size of ready to boot request (%zu %zu)\n",
__func__, op->request->payload_size,
sizeof(*rtb_request));
ret = -EINVAL;
goto queue_work;
}
rtb_request = op->request->payload;
status = rtb_request->status;
/* Return error if the blob was invalid */
if (status == GB_BOOTROM_BOOT_STATUS_INVALID) {
ret = -EINVAL;
goto queue_work;
}
/*
* XXX Should we return error for insecure firmware?
*/
dev_dbg(dev, "ready to boot: 0x%x, 0\n", status);
queue_work:
/*
* Refresh timeout, the Interface shall load the new personality and
* send a new hotplug request, which shall get rid of the bootrom
* connection. As that can take some time, increase the timeout a bit.
*/
gb_bootrom_set_timeout(bootrom, NEXT_REQ_MODE_SWITCH,
MODE_SWITCH_TIMEOUT_MS);
return ret;
}
static int gb_bootrom_request_handler(struct gb_operation *op)
{
u8 type = op->type;
switch (type) {
case GB_BOOTROM_TYPE_FIRMWARE_SIZE:
return gb_bootrom_firmware_size_request(op);
case GB_BOOTROM_TYPE_GET_FIRMWARE:
return gb_bootrom_get_firmware(op);
case GB_BOOTROM_TYPE_READY_TO_BOOT:
return gb_bootrom_ready_to_boot(op);
default:
dev_err(&op->connection->bundle->dev,
"unsupported request: %u\n", type);
return -EINVAL;
}
}
static int gb_bootrom_get_version(struct gb_bootrom *bootrom)
{
struct gb_bundle *bundle = bootrom->connection->bundle;
struct gb_bootrom_version_request request;
struct gb_bootrom_version_response response;
int ret;
request.major = GB_BOOTROM_VERSION_MAJOR;
request.minor = GB_BOOTROM_VERSION_MINOR;
ret = gb_operation_sync(bootrom->connection,
GB_BOOTROM_TYPE_VERSION,
&request, sizeof(request), &response,
sizeof(response));
if (ret) {
dev_err(&bundle->dev,
"failed to get protocol version: %d\n",
ret);
return ret;
}
if (response.major > request.major) {
dev_err(&bundle->dev,
"unsupported major protocol version (%u > %u)\n",
response.major, request.major);
return -ENOTSUPP;
}
bootrom->protocol_major = response.major;
bootrom->protocol_minor = response.minor;
dev_dbg(&bundle->dev, "%s - %u.%u\n", __func__, response.major,
response.minor);
return 0;
}
static int gb_bootrom_probe(struct gb_bundle *bundle,
const struct greybus_bundle_id *id)
{
struct greybus_descriptor_cport *cport_desc;
struct gb_connection *connection;
struct gb_bootrom *bootrom;
int ret;
if (bundle->num_cports != 1)
return -ENODEV;
cport_desc = &bundle->cport_desc[0];
if (cport_desc->protocol_id != GREYBUS_PROTOCOL_BOOTROM)
return -ENODEV;
bootrom = kzalloc(sizeof(*bootrom), GFP_KERNEL);
if (!bootrom)
return -ENOMEM;
connection = gb_connection_create(bundle,
le16_to_cpu(cport_desc->id),
gb_bootrom_request_handler);
if (IS_ERR(connection)) {
ret = PTR_ERR(connection);
goto err_free_bootrom;
}
gb_connection_set_data(connection, bootrom);
bootrom->connection = connection;
mutex_init(&bootrom->mutex);
INIT_DELAYED_WORK(&bootrom->dwork, gb_bootrom_timedout);
greybus_set_drvdata(bundle, bootrom);
ret = gb_connection_enable_tx(connection);
if (ret)
goto err_connection_destroy;
ret = gb_bootrom_get_version(bootrom);
if (ret)
goto err_connection_disable;
bootrom_es2_fixup_vid_pid(bootrom);
ret = gb_connection_enable(connection);
if (ret)
goto err_connection_disable;
/* Refresh timeout */
gb_bootrom_set_timeout(bootrom, NEXT_REQ_FIRMWARE_SIZE,
NEXT_REQ_TIMEOUT_MS);
/* Tell bootrom we're ready. */
ret = gb_operation_sync(connection, GB_BOOTROM_TYPE_AP_READY, NULL, 0,
NULL, 0);
if (ret) {
dev_err(&connection->bundle->dev,
"failed to send AP READY: %d\n", ret);
goto err_cancel_timeout;
}
dev_dbg(&bundle->dev, "AP_READY sent\n");
return 0;
err_cancel_timeout:
gb_bootrom_cancel_timeout(bootrom);
err_connection_disable:
gb_connection_disable(connection);
err_connection_destroy:
gb_connection_destroy(connection);
err_free_bootrom:
kfree(bootrom);
return ret;
}
static void gb_bootrom_disconnect(struct gb_bundle *bundle)
{
struct gb_bootrom *bootrom = greybus_get_drvdata(bundle);
gb_connection_disable(bootrom->connection);
/* Disable timeouts */
gb_bootrom_cancel_timeout(bootrom);
/*
* Release firmware:
*
* As the connection and the delayed work are already disabled, we don't
* need to lock access to bootrom->fw here.
*/
free_firmware(bootrom);
gb_connection_destroy(bootrom->connection);
kfree(bootrom);
}
static const struct greybus_bundle_id gb_bootrom_id_table[] = {
{ GREYBUS_DEVICE_CLASS(GREYBUS_CLASS_BOOTROM) },
{ }
};
static struct greybus_driver gb_bootrom_driver = {
.name = "bootrom",
.probe = gb_bootrom_probe,
.disconnect = gb_bootrom_disconnect,
.id_table = gb_bootrom_id_table,
};
module_greybus_driver(gb_bootrom_driver);
MODULE_LICENSE("GPL v2");