diff options
Diffstat (limited to 'drivers/misc/mei/interrupt.c')
-rw-r--r-- | drivers/misc/mei/interrupt.c | 655 |
1 files changed, 655 insertions, 0 deletions
diff --git a/drivers/misc/mei/interrupt.c b/drivers/misc/mei/interrupt.c new file mode 100644 index 000000000..070632215 --- /dev/null +++ b/drivers/misc/mei/interrupt.c @@ -0,0 +1,655 @@ +// 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> +#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 *vtag_hdr = NULL; + + ext = mei_ext_begin(meta); + do { + switch (ext->type) { + case MEI_EXT_HDR_VTAG: + vtag_hdr = (struct mei_ext_hdr_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_hdr) { + cl_dbg(dev, cl, "vtag not found in extended header.\n"); + cb->status = -EPROTO; + goto discard; + } + + cl_dbg(dev, cl, "vtag: %d\n", vtag_hdr->vtag); + if (cb->vtag && cb->vtag != vtag_hdr->vtag) { + cl_err(dev, cl, "mismatched tag: %d != %d\n", + cb->vtag, vtag_hdr->vtag); + cb->status = -EPROTO; + goto discard; + } + cb->vtag = vtag_hdr->vtag; + } + + 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); + + list_move_tail(&cb->list, &cl->rd_pending); + + return 0; +} + +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; +} + +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) + 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; +} + +/** + * 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 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]) { + dev->rd_msg_hdr[1] = mei_read_hdr(dev); + dev->rd_msg_hdr_count++; + (*slots)--; + dev_dbg(dev->dev, "extended header is %08x\n", dev->rd_msg_hdr[1]); + } + 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; + case MEI_FOP_DMA_MAP: + ret = mei_cl_irq_dma_map(cl, cb, cmpl_list); + if (ret) + return ret; + break; + case MEI_FOP_DMA_UNMAP: + ret = mei_cl_irq_dma_unmap(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); +} |