// SPDX-License-Identifier: GPL-2.0
|
/*
|
* Copyright (c) 2003-2018, Intel Corporation. All rights reserved.
|
* Intel Management Engine Interface (Intel MEI) Linux driver
|
*/
|
|
#include <linux/export.h>
|
#include <linux/kthread.h>
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#include <linux/interrupt.h>
|
#include <linux/fs.h>
|
#include <linux/jiffies.h>
|
#include <linux/slab.h>
|
#include <linux/pm_runtime.h>
|
|
#include <linux/mei.h>
|
|
#include "mei_dev.h"
|
#include "hbm.h"
|
#include "client.h"
|
|
|
/**
|
* mei_irq_compl_handler - dispatch complete handlers
|
* for the completed callbacks
|
*
|
* @dev: mei device
|
* @cmpl_list: list of completed cbs
|
*/
|
void mei_irq_compl_handler(struct mei_device *dev, struct list_head *cmpl_list)
|
{
|
struct mei_cl_cb *cb, *next;
|
struct mei_cl *cl;
|
|
list_for_each_entry_safe(cb, next, cmpl_list, list) {
|
cl = cb->cl;
|
list_del_init(&cb->list);
|
|
dev_dbg(dev->dev, "completing call back.\n");
|
mei_cl_complete(cl, cb);
|
}
|
}
|
EXPORT_SYMBOL_GPL(mei_irq_compl_handler);
|
|
/**
|
* mei_cl_hbm_equal - check if hbm is addressed to the client
|
*
|
* @cl: host client
|
* @mei_hdr: header of mei client message
|
*
|
* Return: true if matches, false otherwise
|
*/
|
static inline int mei_cl_hbm_equal(struct mei_cl *cl,
|
struct mei_msg_hdr *mei_hdr)
|
{
|
return mei_cl_host_addr(cl) == mei_hdr->host_addr &&
|
mei_cl_me_id(cl) == mei_hdr->me_addr;
|
}
|
|
/**
|
* mei_irq_discard_msg - discard received message
|
*
|
* @dev: mei device
|
* @hdr: message header
|
* @discard_len: the length of the message to discard (excluding header)
|
*/
|
static void mei_irq_discard_msg(struct mei_device *dev, struct mei_msg_hdr *hdr,
|
size_t discard_len)
|
{
|
if (hdr->dma_ring) {
|
mei_dma_ring_read(dev, NULL,
|
hdr->extension[dev->rd_msg_hdr_count - 2]);
|
discard_len = 0;
|
}
|
/*
|
* no need to check for size as it is guarantied
|
* that length fits into rd_msg_buf
|
*/
|
mei_read_slots(dev, dev->rd_msg_buf, discard_len);
|
dev_dbg(dev->dev, "discarding message " MEI_HDR_FMT "\n",
|
MEI_HDR_PRM(hdr));
|
}
|
|
/**
|
* mei_cl_irq_read_msg - process client message
|
*
|
* @cl: reading client
|
* @mei_hdr: header of mei client message
|
* @meta: extend meta header
|
* @cmpl_list: completion list
|
*
|
* Return: always 0
|
*/
|
static int mei_cl_irq_read_msg(struct mei_cl *cl,
|
struct mei_msg_hdr *mei_hdr,
|
struct mei_ext_meta_hdr *meta,
|
struct list_head *cmpl_list)
|
{
|
struct mei_device *dev = cl->dev;
|
struct mei_cl_cb *cb;
|
|
size_t buf_sz;
|
u32 length;
|
int ext_len;
|
|
length = mei_hdr->length;
|
ext_len = 0;
|
if (mei_hdr->extended) {
|
ext_len = sizeof(*meta) + mei_slots2data(meta->size);
|
length -= ext_len;
|
}
|
|
cb = list_first_entry_or_null(&cl->rd_pending, struct mei_cl_cb, list);
|
if (!cb) {
|
if (!mei_cl_is_fixed_address(cl)) {
|
cl_err(dev, cl, "pending read cb not found\n");
|
goto discard;
|
}
|
cb = mei_cl_alloc_cb(cl, mei_cl_mtu(cl), MEI_FOP_READ, cl->fp);
|
if (!cb)
|
goto discard;
|
list_add_tail(&cb->list, &cl->rd_pending);
|
}
|
|
if (mei_hdr->extended) {
|
struct mei_ext_hdr *ext;
|
struct mei_ext_hdr *vtag = NULL;
|
|
ext = mei_ext_begin(meta);
|
do {
|
switch (ext->type) {
|
case MEI_EXT_HDR_VTAG:
|
vtag = ext;
|
break;
|
case MEI_EXT_HDR_NONE:
|
fallthrough;
|
default:
|
cb->status = -EPROTO;
|
break;
|
}
|
|
ext = mei_ext_next(ext);
|
} while (!mei_ext_last(meta, ext));
|
|
if (!vtag) {
|
cl_dbg(dev, cl, "vtag not found in extended header.\n");
|
cb->status = -EPROTO;
|
goto discard;
|
}
|
|
cl_dbg(dev, cl, "vtag: %d\n", vtag->ext_payload[0]);
|
if (cb->vtag && cb->vtag != vtag->ext_payload[0]) {
|
cl_err(dev, cl, "mismatched tag: %d != %d\n",
|
cb->vtag, vtag->ext_payload[0]);
|
cb->status = -EPROTO;
|
goto discard;
|
}
|
cb->vtag = vtag->ext_payload[0];
|
}
|
|
if (!mei_cl_is_connected(cl)) {
|
cl_dbg(dev, cl, "not connected\n");
|
cb->status = -ENODEV;
|
goto discard;
|
}
|
|
if (mei_hdr->dma_ring)
|
length = mei_hdr->extension[mei_data2slots(ext_len)];
|
|
buf_sz = length + cb->buf_idx;
|
/* catch for integer overflow */
|
if (buf_sz < cb->buf_idx) {
|
cl_err(dev, cl, "message is too big len %d idx %zu\n",
|
length, cb->buf_idx);
|
cb->status = -EMSGSIZE;
|
goto discard;
|
}
|
|
if (cb->buf.size < buf_sz) {
|
cl_dbg(dev, cl, "message overflow. size %zu len %d idx %zu\n",
|
cb->buf.size, length, cb->buf_idx);
|
cb->status = -EMSGSIZE;
|
goto discard;
|
}
|
|
if (mei_hdr->dma_ring) {
|
mei_dma_ring_read(dev, cb->buf.data + cb->buf_idx, length);
|
/* for DMA read 0 length to generate interrupt to the device */
|
mei_read_slots(dev, cb->buf.data + cb->buf_idx, 0);
|
} else {
|
mei_read_slots(dev, cb->buf.data + cb->buf_idx, length);
|
}
|
|
cb->buf_idx += length;
|
|
if (mei_hdr->msg_complete) {
|
cl_dbg(dev, cl, "completed read length = %zu\n", cb->buf_idx);
|
list_move_tail(&cb->list, cmpl_list);
|
} else {
|
pm_runtime_mark_last_busy(dev->dev);
|
pm_request_autosuspend(dev->dev);
|
}
|
|
return 0;
|
|
discard:
|
if (cb)
|
list_move_tail(&cb->list, cmpl_list);
|
mei_irq_discard_msg(dev, mei_hdr, length);
|
return 0;
|
}
|
|
/**
|
* mei_cl_irq_disconnect_rsp - send disconnection response message
|
*
|
* @cl: client
|
* @cb: callback block.
|
* @cmpl_list: complete list.
|
*
|
* Return: 0, OK; otherwise, error.
|
*/
|
static int mei_cl_irq_disconnect_rsp(struct mei_cl *cl, struct mei_cl_cb *cb,
|
struct list_head *cmpl_list)
|
{
|
struct mei_device *dev = cl->dev;
|
u32 msg_slots;
|
int slots;
|
int ret;
|
|
msg_slots = mei_hbm2slots(sizeof(struct hbm_client_connect_response));
|
slots = mei_hbuf_empty_slots(dev);
|
if (slots < 0)
|
return -EOVERFLOW;
|
|
if ((u32)slots < msg_slots)
|
return -EMSGSIZE;
|
|
ret = mei_hbm_cl_disconnect_rsp(dev, cl);
|
list_move_tail(&cb->list, cmpl_list);
|
|
return ret;
|
}
|
|
/**
|
* mei_cl_irq_read - processes client read related operation from the
|
* interrupt thread context - request for flow control credits
|
*
|
* @cl: client
|
* @cb: callback block.
|
* @cmpl_list: complete list.
|
*
|
* Return: 0, OK; otherwise, error.
|
*/
|
static int mei_cl_irq_read(struct mei_cl *cl, struct mei_cl_cb *cb,
|
struct list_head *cmpl_list)
|
{
|
struct mei_device *dev = cl->dev;
|
u32 msg_slots;
|
int slots;
|
int ret;
|
|
if (!list_empty(&cl->rd_pending))
|
return 0;
|
|
msg_slots = mei_hbm2slots(sizeof(struct hbm_flow_control));
|
slots = mei_hbuf_empty_slots(dev);
|
if (slots < 0)
|
return -EOVERFLOW;
|
|
if ((u32)slots < msg_slots)
|
return -EMSGSIZE;
|
|
ret = mei_hbm_cl_flow_control_req(dev, cl);
|
if (ret) {
|
cl->status = ret;
|
cb->buf_idx = 0;
|
list_move_tail(&cb->list, cmpl_list);
|
return ret;
|
}
|
|
pm_runtime_mark_last_busy(dev->dev);
|
pm_request_autosuspend(dev->dev);
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|
list_move_tail(&cb->list, &cl->rd_pending);
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|
return 0;
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}
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|
static inline bool hdr_is_hbm(struct mei_msg_hdr *mei_hdr)
|
{
|
return mei_hdr->host_addr == 0 && mei_hdr->me_addr == 0;
|
}
|
|
static inline bool hdr_is_fixed(struct mei_msg_hdr *mei_hdr)
|
{
|
return mei_hdr->host_addr == 0 && mei_hdr->me_addr != 0;
|
}
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|
static inline int hdr_is_valid(u32 msg_hdr)
|
{
|
struct mei_msg_hdr *mei_hdr;
|
u32 expected_len = 0;
|
|
mei_hdr = (struct mei_msg_hdr *)&msg_hdr;
|
if (!msg_hdr || mei_hdr->reserved)
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return -EBADMSG;
|
|
if (mei_hdr->dma_ring)
|
expected_len += MEI_SLOT_SIZE;
|
if (mei_hdr->extended)
|
expected_len += MEI_SLOT_SIZE;
|
if (mei_hdr->length < expected_len)
|
return -EBADMSG;
|
|
return 0;
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}
|
|
/**
|
* mei_irq_read_handler - bottom half read routine after ISR to
|
* handle the read processing.
|
*
|
* @dev: the device structure
|
* @cmpl_list: An instance of our list structure
|
* @slots: slots to read.
|
*
|
* Return: 0 on success, <0 on failure.
|
*/
|
int mei_irq_read_handler(struct mei_device *dev,
|
struct list_head *cmpl_list, s32 *slots)
|
{
|
struct mei_msg_hdr *mei_hdr;
|
struct mei_ext_meta_hdr *meta_hdr = NULL;
|
struct mei_cl *cl;
|
int ret;
|
u32 ext_meta_hdr_u32;
|
u32 hdr_size_left;
|
u32 hdr_size_ext;
|
int i;
|
int ext_hdr_end;
|
|
if (!dev->rd_msg_hdr[0]) {
|
dev->rd_msg_hdr[0] = mei_read_hdr(dev);
|
dev->rd_msg_hdr_count = 1;
|
(*slots)--;
|
dev_dbg(dev->dev, "slots =%08x.\n", *slots);
|
|
ret = hdr_is_valid(dev->rd_msg_hdr[0]);
|
if (ret) {
|
dev_err(dev->dev, "corrupted message header 0x%08X\n",
|
dev->rd_msg_hdr[0]);
|
goto end;
|
}
|
}
|
|
mei_hdr = (struct mei_msg_hdr *)dev->rd_msg_hdr;
|
dev_dbg(dev->dev, MEI_HDR_FMT, MEI_HDR_PRM(mei_hdr));
|
|
if (mei_slots2data(*slots) < mei_hdr->length) {
|
dev_err(dev->dev, "less data available than length=%08x.\n",
|
*slots);
|
/* we can't read the message */
|
ret = -ENODATA;
|
goto end;
|
}
|
|
ext_hdr_end = 1;
|
hdr_size_left = mei_hdr->length;
|
|
if (mei_hdr->extended) {
|
if (!dev->rd_msg_hdr[1]) {
|
ext_meta_hdr_u32 = mei_read_hdr(dev);
|
dev->rd_msg_hdr[1] = ext_meta_hdr_u32;
|
dev->rd_msg_hdr_count++;
|
(*slots)--;
|
dev_dbg(dev->dev, "extended header is %08x\n",
|
ext_meta_hdr_u32);
|
}
|
meta_hdr = ((struct mei_ext_meta_hdr *)dev->rd_msg_hdr + 1);
|
if (check_add_overflow((u32)sizeof(*meta_hdr),
|
mei_slots2data(meta_hdr->size),
|
&hdr_size_ext)) {
|
dev_err(dev->dev, "extended message size too big %d\n",
|
meta_hdr->size);
|
return -EBADMSG;
|
}
|
if (hdr_size_left < hdr_size_ext) {
|
dev_err(dev->dev, "corrupted message header len %d\n",
|
mei_hdr->length);
|
return -EBADMSG;
|
}
|
hdr_size_left -= hdr_size_ext;
|
|
ext_hdr_end = meta_hdr->size + 2;
|
for (i = dev->rd_msg_hdr_count; i < ext_hdr_end; i++) {
|
dev->rd_msg_hdr[i] = mei_read_hdr(dev);
|
dev_dbg(dev->dev, "extended header %d is %08x\n", i,
|
dev->rd_msg_hdr[i]);
|
dev->rd_msg_hdr_count++;
|
(*slots)--;
|
}
|
}
|
|
if (mei_hdr->dma_ring) {
|
if (hdr_size_left != sizeof(dev->rd_msg_hdr[ext_hdr_end])) {
|
dev_err(dev->dev, "corrupted message header len %d\n",
|
mei_hdr->length);
|
return -EBADMSG;
|
}
|
|
dev->rd_msg_hdr[ext_hdr_end] = mei_read_hdr(dev);
|
dev->rd_msg_hdr_count++;
|
(*slots)--;
|
mei_hdr->length -= sizeof(dev->rd_msg_hdr[ext_hdr_end]);
|
}
|
|
/* HBM message */
|
if (hdr_is_hbm(mei_hdr)) {
|
ret = mei_hbm_dispatch(dev, mei_hdr);
|
if (ret) {
|
dev_dbg(dev->dev, "mei_hbm_dispatch failed ret = %d\n",
|
ret);
|
goto end;
|
}
|
goto reset_slots;
|
}
|
|
/* find recipient cl */
|
list_for_each_entry(cl, &dev->file_list, link) {
|
if (mei_cl_hbm_equal(cl, mei_hdr)) {
|
cl_dbg(dev, cl, "got a message\n");
|
ret = mei_cl_irq_read_msg(cl, mei_hdr, meta_hdr, cmpl_list);
|
goto reset_slots;
|
}
|
}
|
|
/* if no recipient cl was found we assume corrupted header */
|
/* A message for not connected fixed address clients
|
* should be silently discarded
|
* On power down client may be force cleaned,
|
* silently discard such messages
|
*/
|
if (hdr_is_fixed(mei_hdr) ||
|
dev->dev_state == MEI_DEV_POWER_DOWN) {
|
mei_irq_discard_msg(dev, mei_hdr, mei_hdr->length);
|
ret = 0;
|
goto reset_slots;
|
}
|
dev_err(dev->dev, "no destination client found 0x%08X\n", dev->rd_msg_hdr[0]);
|
ret = -EBADMSG;
|
goto end;
|
|
reset_slots:
|
/* reset the number of slots and header */
|
memset(dev->rd_msg_hdr, 0, sizeof(dev->rd_msg_hdr));
|
dev->rd_msg_hdr_count = 0;
|
*slots = mei_count_full_read_slots(dev);
|
if (*slots == -EOVERFLOW) {
|
/* overflow - reset */
|
dev_err(dev->dev, "resetting due to slots overflow.\n");
|
/* set the event since message has been read */
|
ret = -ERANGE;
|
goto end;
|
}
|
end:
|
return ret;
|
}
|
EXPORT_SYMBOL_GPL(mei_irq_read_handler);
|
|
|
/**
|
* mei_irq_write_handler - dispatch write requests
|
* after irq received
|
*
|
* @dev: the device structure
|
* @cmpl_list: An instance of our list structure
|
*
|
* Return: 0 on success, <0 on failure.
|
*/
|
int mei_irq_write_handler(struct mei_device *dev, struct list_head *cmpl_list)
|
{
|
|
struct mei_cl *cl;
|
struct mei_cl_cb *cb, *next;
|
s32 slots;
|
int ret;
|
|
|
if (!mei_hbuf_acquire(dev))
|
return 0;
|
|
slots = mei_hbuf_empty_slots(dev);
|
if (slots < 0)
|
return -EOVERFLOW;
|
|
if (slots == 0)
|
return -EMSGSIZE;
|
|
/* complete all waiting for write CB */
|
dev_dbg(dev->dev, "complete all waiting for write cb.\n");
|
|
list_for_each_entry_safe(cb, next, &dev->write_waiting_list, list) {
|
cl = cb->cl;
|
|
cl->status = 0;
|
cl_dbg(dev, cl, "MEI WRITE COMPLETE\n");
|
cl->writing_state = MEI_WRITE_COMPLETE;
|
list_move_tail(&cb->list, cmpl_list);
|
}
|
|
/* complete control write list CB */
|
dev_dbg(dev->dev, "complete control write list cb.\n");
|
list_for_each_entry_safe(cb, next, &dev->ctrl_wr_list, list) {
|
cl = cb->cl;
|
switch (cb->fop_type) {
|
case MEI_FOP_DISCONNECT:
|
/* send disconnect message */
|
ret = mei_cl_irq_disconnect(cl, cb, cmpl_list);
|
if (ret)
|
return ret;
|
|
break;
|
case MEI_FOP_READ:
|
/* send flow control message */
|
ret = mei_cl_irq_read(cl, cb, cmpl_list);
|
if (ret)
|
return ret;
|
|
break;
|
case MEI_FOP_CONNECT:
|
/* connect message */
|
ret = mei_cl_irq_connect(cl, cb, cmpl_list);
|
if (ret)
|
return ret;
|
|
break;
|
case MEI_FOP_DISCONNECT_RSP:
|
/* send disconnect resp */
|
ret = mei_cl_irq_disconnect_rsp(cl, cb, cmpl_list);
|
if (ret)
|
return ret;
|
break;
|
|
case MEI_FOP_NOTIFY_START:
|
case MEI_FOP_NOTIFY_STOP:
|
ret = mei_cl_irq_notify(cl, cb, cmpl_list);
|
if (ret)
|
return ret;
|
break;
|
default:
|
BUG();
|
}
|
|
}
|
/* complete write list CB */
|
dev_dbg(dev->dev, "complete write list cb.\n");
|
list_for_each_entry_safe(cb, next, &dev->write_list, list) {
|
cl = cb->cl;
|
ret = mei_cl_irq_write(cl, cb, cmpl_list);
|
if (ret)
|
return ret;
|
}
|
return 0;
|
}
|
EXPORT_SYMBOL_GPL(mei_irq_write_handler);
|
|
|
/**
|
* mei_connect_timeout - connect/disconnect timeouts
|
*
|
* @cl: host client
|
*/
|
static void mei_connect_timeout(struct mei_cl *cl)
|
{
|
struct mei_device *dev = cl->dev;
|
|
if (cl->state == MEI_FILE_CONNECTING) {
|
if (dev->hbm_f_dot_supported) {
|
cl->state = MEI_FILE_DISCONNECT_REQUIRED;
|
wake_up(&cl->wait);
|
return;
|
}
|
}
|
mei_reset(dev);
|
}
|
|
#define MEI_STALL_TIMER_FREQ (2 * HZ)
|
/**
|
* mei_schedule_stall_timer - re-arm stall_timer work
|
*
|
* Schedule stall timer
|
*
|
* @dev: the device structure
|
*/
|
void mei_schedule_stall_timer(struct mei_device *dev)
|
{
|
schedule_delayed_work(&dev->timer_work, MEI_STALL_TIMER_FREQ);
|
}
|
|
/**
|
* mei_timer - timer function.
|
*
|
* @work: pointer to the work_struct structure
|
*
|
*/
|
void mei_timer(struct work_struct *work)
|
{
|
struct mei_cl *cl;
|
struct mei_device *dev = container_of(work,
|
struct mei_device, timer_work.work);
|
bool reschedule_timer = false;
|
|
mutex_lock(&dev->device_lock);
|
|
/* Catch interrupt stalls during HBM init handshake */
|
if (dev->dev_state == MEI_DEV_INIT_CLIENTS &&
|
dev->hbm_state != MEI_HBM_IDLE) {
|
|
if (dev->init_clients_timer) {
|
if (--dev->init_clients_timer == 0) {
|
dev_err(dev->dev, "timer: init clients timeout hbm_state = %d.\n",
|
dev->hbm_state);
|
mei_reset(dev);
|
goto out;
|
}
|
reschedule_timer = true;
|
}
|
}
|
|
if (dev->dev_state != MEI_DEV_ENABLED)
|
goto out;
|
|
/*** connect/disconnect timeouts ***/
|
list_for_each_entry(cl, &dev->file_list, link) {
|
if (cl->timer_count) {
|
if (--cl->timer_count == 0) {
|
dev_err(dev->dev, "timer: connect/disconnect timeout.\n");
|
mei_connect_timeout(cl);
|
goto out;
|
}
|
reschedule_timer = true;
|
}
|
}
|
|
out:
|
if (dev->dev_state != MEI_DEV_DISABLED && reschedule_timer)
|
mei_schedule_stall_timer(dev);
|
|
mutex_unlock(&dev->device_lock);
|
}
|
