diff options
Diffstat (limited to 'drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c')
| -rw-r--r-- | drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c | 897 |
1 files changed, 897 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c b/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c new file mode 100644 index 000000000000..b49115517510 --- /dev/null +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c @@ -0,0 +1,897 @@ +// SPDX-License-Identifier: MIT +/* + * Copyright © 2016-2019 Intel Corporation + */ + +#include "i915_drv.h" +#include "intel_guc_ct.h" + +#ifdef CONFIG_DRM_I915_DEBUG_GUC +#define CT_DEBUG_DRIVER(...) DRM_DEBUG_DRIVER(__VA_ARGS__) +#else +#define CT_DEBUG_DRIVER(...) do { } while (0) +#endif + +struct ct_request { + struct list_head link; + u32 fence; + u32 status; + u32 response_len; + u32 *response_buf; +}; + +struct ct_incoming_request { + struct list_head link; + u32 msg[]; +}; + +enum { CTB_SEND = 0, CTB_RECV = 1 }; + +enum { CTB_OWNER_HOST = 0 }; + +static void ct_incoming_request_worker_func(struct work_struct *w); + +/** + * intel_guc_ct_init_early - Initialize CT state without requiring device access + * @ct: pointer to CT struct + */ +void intel_guc_ct_init_early(struct intel_guc_ct *ct) +{ + /* we're using static channel owners */ + ct->host_channel.owner = CTB_OWNER_HOST; + + spin_lock_init(&ct->lock); + INIT_LIST_HEAD(&ct->pending_requests); + INIT_LIST_HEAD(&ct->incoming_requests); + INIT_WORK(&ct->worker, ct_incoming_request_worker_func); +} + +static inline struct intel_guc *ct_to_guc(struct intel_guc_ct *ct) +{ + return container_of(ct, struct intel_guc, ct); +} + +static inline const char *guc_ct_buffer_type_to_str(u32 type) +{ + switch (type) { + case INTEL_GUC_CT_BUFFER_TYPE_SEND: + return "SEND"; + case INTEL_GUC_CT_BUFFER_TYPE_RECV: + return "RECV"; + default: + return "<invalid>"; + } +} + +static void guc_ct_buffer_desc_init(struct guc_ct_buffer_desc *desc, + u32 cmds_addr, u32 size, u32 owner) +{ + CT_DEBUG_DRIVER("CT: desc %p init addr=%#x size=%u owner=%u\n", + desc, cmds_addr, size, owner); + memset(desc, 0, sizeof(*desc)); + desc->addr = cmds_addr; + desc->size = size; + desc->owner = owner; +} + +static void guc_ct_buffer_desc_reset(struct guc_ct_buffer_desc *desc) +{ + CT_DEBUG_DRIVER("CT: desc %p reset head=%u tail=%u\n", + desc, desc->head, desc->tail); + desc->head = 0; + desc->tail = 0; + desc->is_in_error = 0; +} + +static int guc_action_register_ct_buffer(struct intel_guc *guc, + u32 desc_addr, + u32 type) +{ + u32 action[] = { + INTEL_GUC_ACTION_REGISTER_COMMAND_TRANSPORT_BUFFER, + desc_addr, + sizeof(struct guc_ct_buffer_desc), + type + }; + int err; + + /* Can't use generic send(), CT registration must go over MMIO */ + err = intel_guc_send_mmio(guc, action, ARRAY_SIZE(action), NULL, 0); + if (err) + DRM_ERROR("CT: register %s buffer failed; err=%d\n", + guc_ct_buffer_type_to_str(type), err); + return err; +} + +static int guc_action_deregister_ct_buffer(struct intel_guc *guc, + u32 owner, + u32 type) +{ + u32 action[] = { + INTEL_GUC_ACTION_DEREGISTER_COMMAND_TRANSPORT_BUFFER, + owner, + type + }; + int err; + + /* Can't use generic send(), CT deregistration must go over MMIO */ + err = intel_guc_send_mmio(guc, action, ARRAY_SIZE(action), NULL, 0); + if (err) + DRM_ERROR("CT: deregister %s buffer failed; owner=%d err=%d\n", + guc_ct_buffer_type_to_str(type), owner, err); + return err; +} + +static int ctch_init(struct intel_guc *guc, + struct intel_guc_ct_channel *ctch) +{ + struct i915_vma *vma; + void *blob; + int err; + int i; + + GEM_BUG_ON(ctch->vma); + + /* We allocate 1 page to hold both descriptors and both buffers. + * ___________..................... + * |desc (SEND)| : + * |___________| PAGE/4 + * :___________....................: + * |desc (RECV)| : + * |___________| PAGE/4 + * :_______________________________: + * |cmds (SEND) | + * | PAGE/4 + * |_______________________________| + * |cmds (RECV) | + * | PAGE/4 + * |_______________________________| + * + * Each message can use a maximum of 32 dwords and we don't expect to + * have more than 1 in flight at any time, so we have enough space. + * Some logic further ahead will rely on the fact that there is only 1 + * page and that it is always mapped, so if the size is changed the + * other code will need updating as well. + */ + + /* allocate vma */ + vma = intel_guc_allocate_vma(guc, PAGE_SIZE); + if (IS_ERR(vma)) { + err = PTR_ERR(vma); + goto err_out; + } + ctch->vma = vma; + + /* map first page */ + blob = i915_gem_object_pin_map(vma->obj, I915_MAP_WB); + if (IS_ERR(blob)) { + err = PTR_ERR(blob); + goto err_vma; + } + CT_DEBUG_DRIVER("CT: vma base=%#x\n", + intel_guc_ggtt_offset(guc, ctch->vma)); + + /* store pointers to desc and cmds */ + for (i = 0; i < ARRAY_SIZE(ctch->ctbs); i++) { + GEM_BUG_ON((i != CTB_SEND) && (i != CTB_RECV)); + ctch->ctbs[i].desc = blob + PAGE_SIZE/4 * i; + ctch->ctbs[i].cmds = blob + PAGE_SIZE/4 * i + PAGE_SIZE/2; + } + + return 0; + +err_vma: + i915_vma_unpin_and_release(&ctch->vma, 0); +err_out: + CT_DEBUG_DRIVER("CT: channel %d initialization failed; err=%d\n", + ctch->owner, err); + return err; +} + +static void ctch_fini(struct intel_guc *guc, + struct intel_guc_ct_channel *ctch) +{ + GEM_BUG_ON(ctch->enabled); + + i915_vma_unpin_and_release(&ctch->vma, I915_VMA_RELEASE_MAP); +} + +static int ctch_enable(struct intel_guc *guc, + struct intel_guc_ct_channel *ctch) +{ + u32 base; + int err; + int i; + + GEM_BUG_ON(!ctch->vma); + + GEM_BUG_ON(ctch->enabled); + + /* vma should be already allocated and map'ed */ + base = intel_guc_ggtt_offset(guc, ctch->vma); + + /* (re)initialize descriptors + * cmds buffers are in the second half of the blob page + */ + for (i = 0; i < ARRAY_SIZE(ctch->ctbs); i++) { + GEM_BUG_ON((i != CTB_SEND) && (i != CTB_RECV)); + guc_ct_buffer_desc_init(ctch->ctbs[i].desc, + base + PAGE_SIZE/4 * i + PAGE_SIZE/2, + PAGE_SIZE/4, + ctch->owner); + } + + /* register buffers, starting wirh RECV buffer + * descriptors are in first half of the blob + */ + err = guc_action_register_ct_buffer(guc, + base + PAGE_SIZE/4 * CTB_RECV, + INTEL_GUC_CT_BUFFER_TYPE_RECV); + if (unlikely(err)) + goto err_out; + + err = guc_action_register_ct_buffer(guc, + base + PAGE_SIZE/4 * CTB_SEND, + INTEL_GUC_CT_BUFFER_TYPE_SEND); + if (unlikely(err)) + goto err_deregister; + + ctch->enabled = true; + + return 0; + +err_deregister: + guc_action_deregister_ct_buffer(guc, + ctch->owner, + INTEL_GUC_CT_BUFFER_TYPE_RECV); +err_out: + DRM_ERROR("CT: can't open channel %d; err=%d\n", ctch->owner, err); + return err; +} + +static void ctch_disable(struct intel_guc *guc, + struct intel_guc_ct_channel *ctch) +{ + GEM_BUG_ON(!ctch->enabled); + + ctch->enabled = false; + + guc_action_deregister_ct_buffer(guc, + ctch->owner, + INTEL_GUC_CT_BUFFER_TYPE_SEND); + guc_action_deregister_ct_buffer(guc, + ctch->owner, + INTEL_GUC_CT_BUFFER_TYPE_RECV); +} + +static u32 ctch_get_next_fence(struct intel_guc_ct_channel *ctch) +{ + /* For now it's trivial */ + return ++ctch->next_fence; +} + +/** + * DOC: CTB Host to GuC request + * + * Format of the CTB Host to GuC request message is as follows:: + * + * +------------+---------+---------+---------+---------+ + * | msg[0] | [1] | [2] | ... | [n-1] | + * +------------+---------+---------+---------+---------+ + * | MESSAGE | MESSAGE PAYLOAD | + * + HEADER +---------+---------+---------+---------+ + * | | 0 | 1 | ... | n | + * +============+=========+=========+=========+=========+ + * | len >= 1 | FENCE | request specific data | + * +------+-----+---------+---------+---------+---------+ + * + * ^-----------------len-------------------^ + */ + +static int ctb_write(struct intel_guc_ct_buffer *ctb, + const u32 *action, + u32 len /* in dwords */, + u32 fence, + bool want_response) +{ + struct guc_ct_buffer_desc *desc = ctb->desc; + u32 head = desc->head / 4; /* in dwords */ + u32 tail = desc->tail / 4; /* in dwords */ + u32 size = desc->size / 4; /* in dwords */ + u32 used; /* in dwords */ + u32 header; + u32 *cmds = ctb->cmds; + unsigned int i; + + GEM_BUG_ON(desc->size % 4); + GEM_BUG_ON(desc->head % 4); + GEM_BUG_ON(desc->tail % 4); + GEM_BUG_ON(tail >= size); + + /* + * tail == head condition indicates empty. GuC FW does not support + * using up the entire buffer to get tail == head meaning full. + */ + if (tail < head) + used = (size - head) + tail; + else + used = tail - head; + + /* make sure there is a space including extra dw for the fence */ + if (unlikely(used + len + 1 >= size)) + return -ENOSPC; + + /* + * Write the message. The format is the following: + * DW0: header (including action code) + * DW1: fence + * DW2+: action data + */ + header = (len << GUC_CT_MSG_LEN_SHIFT) | + (GUC_CT_MSG_WRITE_FENCE_TO_DESC) | + (want_response ? GUC_CT_MSG_SEND_STATUS : 0) | + (action[0] << GUC_CT_MSG_ACTION_SHIFT); + + CT_DEBUG_DRIVER("CT: writing %*ph %*ph %*ph\n", + 4, &header, 4, &fence, + 4 * (len - 1), &action[1]); + + cmds[tail] = header; + tail = (tail + 1) % size; + + cmds[tail] = fence; + tail = (tail + 1) % size; + + for (i = 1; i < len; i++) { + cmds[tail] = action[i]; + tail = (tail + 1) % size; + } + + /* now update desc tail (back in bytes) */ + desc->tail = tail * 4; + GEM_BUG_ON(desc->tail > desc->size); + + return 0; +} + +/** + * wait_for_ctb_desc_update - Wait for the CT buffer descriptor update. + * @desc: buffer descriptor + * @fence: response fence + * @status: placeholder for status + * + * Guc will update CT buffer descriptor with new fence and status + * after processing the command identified by the fence. Wait for + * specified fence and then read from the descriptor status of the + * command. + * + * Return: + * * 0 response received (status is valid) + * * -ETIMEDOUT no response within hardcoded timeout + * * -EPROTO no response, CT buffer is in error + */ +static int wait_for_ctb_desc_update(struct guc_ct_buffer_desc *desc, + u32 fence, + u32 *status) +{ + int err; + + /* + * Fast commands should complete in less than 10us, so sample quickly + * up to that length of time, then switch to a slower sleep-wait loop. + * No GuC command should ever take longer than 10ms. + */ +#define done (READ_ONCE(desc->fence) == fence) + err = wait_for_us(done, 10); + if (err) + err = wait_for(done, 10); +#undef done + + if (unlikely(err)) { + DRM_ERROR("CT: fence %u failed; reported fence=%u\n", + fence, desc->fence); + + if (WARN_ON(desc->is_in_error)) { + /* Something went wrong with the messaging, try to reset + * the buffer and hope for the best + */ + guc_ct_buffer_desc_reset(desc); + err = -EPROTO; + } + } + + *status = desc->status; + return err; +} + +/** + * wait_for_ct_request_update - Wait for CT request state update. + * @req: pointer to pending request + * @status: placeholder for status + * + * For each sent request, Guc shall send bac CT response message. + * Our message handler will update status of tracked request once + * response message with given fence is received. Wait here and + * check for valid response status value. + * + * Return: + * * 0 response received (status is valid) + * * -ETIMEDOUT no response within hardcoded timeout + */ +static int wait_for_ct_request_update(struct ct_request *req, u32 *status) +{ + int err; + + /* + * Fast commands should complete in less than 10us, so sample quickly + * up to that length of time, then switch to a slower sleep-wait loop. + * No GuC command should ever take longer than 10ms. + */ +#define done INTEL_GUC_MSG_IS_RESPONSE(READ_ONCE(req->status)) + err = wait_for_us(done, 10); + if (err) + err = wait_for(done, 10); +#undef done + + if (unlikely(err)) + DRM_ERROR("CT: fence %u err %d\n", req->fence, err); + + *status = req->status; + return err; +} + +static int ctch_send(struct intel_guc_ct *ct, + struct intel_guc_ct_channel *ctch, + const u32 *action, + u32 len, + u32 *response_buf, + u32 response_buf_size, + u32 *status) +{ + struct intel_guc_ct_buffer *ctb = &ctch->ctbs[CTB_SEND]; + struct guc_ct_buffer_desc *desc = ctb->desc; + struct ct_request request; + unsigned long flags; + u32 fence; + int err; + + GEM_BUG_ON(!ctch->enabled); + GEM_BUG_ON(!len); + GEM_BUG_ON(len & ~GUC_CT_MSG_LEN_MASK); + GEM_BUG_ON(!response_buf && response_buf_size); + + fence = ctch_get_next_fence(ctch); + request.fence = fence; + request.status = 0; + request.response_len = response_buf_size; + request.response_buf = response_buf; + + spin_lock_irqsave(&ct->lock, flags); + list_add_tail(&request.link, &ct->pending_requests); + spin_unlock_irqrestore(&ct->lock, flags); + + err = ctb_write(ctb, action, len, fence, !!response_buf); + if (unlikely(err)) + goto unlink; + + intel_guc_notify(ct_to_guc(ct)); + + if (response_buf) + err = wait_for_ct_request_update(&request, status); + else + err = wait_for_ctb_desc_update(desc, fence, status); + if (unlikely(err)) + goto unlink; + + if (!INTEL_GUC_MSG_IS_RESPONSE_SUCCESS(*status)) { + err = -EIO; + goto unlink; + } + + if (response_buf) { + /* There shall be no data in the status */ + WARN_ON(INTEL_GUC_MSG_TO_DATA(request.status)); + /* Return actual response len */ + err = request.response_len; + } else { + /* There shall be no response payload */ + WARN_ON(request.response_len); + /* Return data decoded from the status dword */ + err = INTEL_GUC_MSG_TO_DATA(*status); + } + +unlink: + spin_lock_irqsave(&ct->lock, flags); + list_del(&request.link); + spin_unlock_irqrestore(&ct->lock, flags); + + return err; +} + +/* + * Command Transport (CT) buffer based GuC send function. + */ +int intel_guc_send_ct(struct intel_guc *guc, const u32 *action, u32 len, + u32 *response_buf, u32 response_buf_size) +{ + struct intel_guc_ct *ct = &guc->ct; + struct intel_guc_ct_channel *ctch = &ct->host_channel; + u32 status = ~0; /* undefined */ + int ret; + + mutex_lock(&guc->send_mutex); + + ret = ctch_send(ct, ctch, action, len, response_buf, response_buf_size, + &status); + if (unlikely(ret < 0)) { + DRM_ERROR("CT: send action %#X failed; err=%d status=%#X\n", + action[0], ret, status); + } else if (unlikely(ret)) { + CT_DEBUG_DRIVER("CT: send action %#x returned %d (%#x)\n", + action[0], ret, ret); + } + + mutex_unlock(&guc->send_mutex); + return ret; +} + +static inline unsigned int ct_header_get_len(u32 header) +{ + return (header >> GUC_CT_MSG_LEN_SHIFT) & GUC_CT_MSG_LEN_MASK; +} + +static inline unsigned int ct_header_get_action(u32 header) +{ + return (header >> GUC_CT_MSG_ACTION_SHIFT) & GUC_CT_MSG_ACTION_MASK; +} + +static inline bool ct_header_is_response(u32 header) +{ + return !!(header & GUC_CT_MSG_IS_RESPONSE); +} + +static int ctb_read(struct intel_guc_ct_buffer *ctb, u32 *data) +{ + struct guc_ct_buffer_desc *desc = ctb->desc; + u32 head = desc->head / 4; /* in dwords */ + u32 tail = desc->tail / 4; /* in dwords */ + u32 size = desc->size / 4; /* in dwords */ + u32 *cmds = ctb->cmds; + s32 available; /* in dwords */ + unsigned int len; + unsigned int i; + + GEM_BUG_ON(desc->size % 4); + GEM_BUG_ON(desc->head % 4); + GEM_BUG_ON(desc->tail % 4); + GEM_BUG_ON(tail >= size); + GEM_BUG_ON(head >= size); + + /* tail == head condition indicates empty */ + available = tail - head; + if (unlikely(available == 0)) + return -ENODATA; + + /* beware of buffer wrap case */ + if (unlikely(available < 0)) + available += size; + CT_DEBUG_DRIVER("CT: available %d (%u:%u)\n", available, head, tail); + GEM_BUG_ON(available < 0); + + data[0] = cmds[head]; + head = (head + 1) % size; + + /* message len with header */ + len = ct_header_get_len(data[0]) + 1; + if (unlikely(len > (u32)available)) { + DRM_ERROR("CT: incomplete message %*ph %*ph %*ph\n", + 4, data, + 4 * (head + available - 1 > size ? + size - head : available - 1), &cmds[head], + 4 * (head + available - 1 > size ? + available - 1 - size + head : 0), &cmds[0]); + return -EPROTO; + } + + for (i = 1; i < len; i++) { + data[i] = cmds[head]; + head = (head + 1) % size; + } + CT_DEBUG_DRIVER("CT: received %*ph\n", 4 * len, data); + + desc->head = head * 4; + return 0; +} + +/** + * DOC: CTB GuC to Host response + * + * Format of the CTB GuC to Host response message is as follows:: + * + * +------------+---------+---------+---------+---------+---------+ + * | msg[0] | [1] | [2] | [3] | ... | [n-1] | + * +------------+---------+---------+---------+---------+---------+ + * | MESSAGE | MESSAGE PAYLOAD | + * + HEADER +---------+---------+---------+---------+---------+ + * | | 0 | 1 | 2 | ... | n | + * +============+=========+=========+=========+=========+=========+ + * | len >= 2 | FENCE | STATUS | response specific data | + * +------+-----+---------+---------+---------+---------+---------+ + * + * ^-----------------------len-----------------------^ + */ + +static int ct_handle_response(struct intel_guc_ct *ct, const u32 *msg) +{ + u32 header = msg[0]; + u32 len = ct_header_get_len(header); + u32 msglen = len + 1; /* total message length including header */ + u32 fence; + u32 status; + u32 datalen; + struct ct_request *req; + bool found = false; + + GEM_BUG_ON(!ct_header_is_response(header)); + GEM_BUG_ON(!in_irq()); + + /* Response payload shall at least include fence and status */ + if (unlikely(len < 2)) { + DRM_ERROR("CT: corrupted response %*ph\n", 4 * msglen, msg); + return -EPROTO; + } + + fence = msg[1]; + status = msg[2]; + datalen = len - 2; + + /* Format of the status follows RESPONSE message */ + if (unlikely(!INTEL_GUC_MSG_IS_RESPONSE(status))) { + DRM_ERROR("CT: corrupted response %*ph\n", 4 * msglen, msg); + return -EPROTO; + } + + CT_DEBUG_DRIVER("CT: response fence %u status %#x\n", fence, status); + + spin_lock(&ct->lock); + list_for_each_entry(req, &ct->pending_requests, link) { + if (unlikely(fence != req->fence)) { + CT_DEBUG_DRIVER("CT: request %u awaits response\n", + req->fence); + continue; + } + if (unlikely(datalen > req->response_len)) { + DRM_ERROR("CT: response %u too long %*ph\n", + req->fence, 4 * msglen, msg); + datalen = 0; + } + if (datalen) + memcpy(req->response_buf, msg + 3, 4 * datalen); + req->response_len = datalen; + WRITE_ONCE(req->status, status); + found = true; + break; + } + spin_unlock(&ct->lock); + + if (!found) + DRM_ERROR("CT: unsolicited response %*ph\n", 4 * msglen, msg); + return 0; +} + +static void ct_process_request(struct intel_guc_ct *ct, + u32 action, u32 len, const u32 *payload) +{ + struct intel_guc *guc = ct_to_guc(ct); + int ret; + + CT_DEBUG_DRIVER("CT: request %x %*ph\n", action, 4 * len, payload); + + switch (action) { + case INTEL_GUC_ACTION_DEFAULT: + ret = intel_guc_to_host_process_recv_msg(guc, payload, len); + if (unlikely(ret)) + goto fail_unexpected; + break; + + default: +fail_unexpected: + DRM_ERROR("CT: unexpected request %x %*ph\n", + action, 4 * len, payload); + break; + } +} + +static bool ct_process_incoming_requests(struct intel_guc_ct *ct) +{ + unsigned long flags; + struct ct_incoming_request *request; + u32 header; + u32 *payload; + bool done; + + spin_lock_irqsave(&ct->lock, flags); + request = list_first_entry_or_null(&ct->incoming_requests, + struct ct_incoming_request, link); + if (request) + list_del(&request->link); + done = !!list_empty(&ct->incoming_requests); + spin_unlock_irqrestore(&ct->lock, flags); + + if (!request) + return true; + + header = request->msg[0]; + payload = &request->msg[1]; + ct_process_request(ct, + ct_header_get_action(header), + ct_header_get_len(header), + payload); + + kfree(request); + return done; +} + +static void ct_incoming_request_worker_func(struct work_struct *w) +{ + struct intel_guc_ct *ct = container_of(w, struct intel_guc_ct, worker); + bool done; + + done = ct_process_incoming_requests(ct); + if (!done) + queue_work(system_unbound_wq, &ct->worker); +} + +/** + * DOC: CTB GuC to Host request + * + * Format of the CTB GuC to Host request message is as follows:: + * + * +------------+---------+---------+---------+---------+---------+ + * | msg[0] | [1] | [2] | [3] | ... | [n-1] | + * +------------+---------+---------+---------+---------+---------+ + * | MESSAGE | MESSAGE PAYLOAD | + * + HEADER +---------+---------+---------+---------+---------+ + * | | 0 | 1 | 2 | ... | n | + * +============+=========+=========+=========+=========+=========+ + * | len | request specific data | + * +------+-----+---------+---------+---------+---------+---------+ + * + * ^-----------------------len-----------------------^ + */ + +static int ct_handle_request(struct intel_guc_ct *ct, const u32 *msg) +{ + u32 header = msg[0]; + u32 len = ct_header_get_len(header); + u32 msglen = len + 1; /* total message length including header */ + struct ct_incoming_request *request; + unsigned long flags; + + GEM_BUG_ON(ct_header_is_response(header)); + + request = kmalloc(sizeof(*request) + 4 * msglen, GFP_ATOMIC); + if (unlikely(!request)) { + DRM_ERROR("CT: dropping request %*ph\n", 4 * msglen, msg); + return 0; /* XXX: -ENOMEM ? */ + } + memcpy(request->msg, msg, 4 * msglen); + + spin_lock_irqsave(&ct->lock, flags); + list_add_tail(&request->link, &ct->incoming_requests); + spin_unlock_irqrestore(&ct->lock, flags); + + queue_work(system_unbound_wq, &ct->worker); + return 0; +} + +static void ct_process_host_channel(struct intel_guc_ct *ct) +{ + struct intel_guc_ct_channel *ctch = &ct->host_channel; + struct intel_guc_ct_buffer *ctb = &ctch->ctbs[CTB_RECV]; + u32 msg[GUC_CT_MSG_LEN_MASK + 1]; /* one extra dw for the header */ + int err = 0; + + if (!ctch->enabled) + return; + + do { + err = ctb_read(ctb, msg); + if (err) + break; + + if (ct_header_is_response(msg[0])) + err = ct_handle_response(ct, msg); + else + err = ct_handle_request(ct, msg); + } while (!err); + + if (GEM_WARN_ON(err == -EPROTO)) { + DRM_ERROR("CT: corrupted message detected!\n"); + ctb->desc->is_in_error = 1; + } +} + +/* + * When we're communicating with the GuC over CT, GuC uses events + * to notify us about new messages being posted on the RECV buffer. + */ +void intel_guc_to_host_event_handler_ct(struct intel_guc *guc) +{ + struct intel_guc_ct *ct = &guc->ct; + + ct_process_host_channel(ct); +} + +/** + * intel_guc_ct_init - Init CT communication + * @ct: pointer to CT struct + * + * Allocate memory required for communication via + * the CT channel. + * + * Return: 0 on success, a negative errno code on failure. + */ +int intel_guc_ct_init(struct intel_guc_ct *ct) +{ + struct intel_guc *guc = ct_to_guc(ct); + struct intel_guc_ct_channel *ctch = &ct->host_channel; + int err; + + err = ctch_init(guc, ctch); + if (unlikely(err)) { + DRM_ERROR("CT: can't open channel %d; err=%d\n", + ctch->owner, err); + return err; + } + + GEM_BUG_ON(!ctch->vma); + return 0; +} + +/** + * intel_guc_ct_fini - Fini CT communication + * @ct: pointer to CT struct + * + * Deallocate memory required for communication via + * the CT channel. + */ +void intel_guc_ct_fini(struct intel_guc_ct *ct) +{ + struct intel_guc *guc = ct_to_guc(ct); + struct intel_guc_ct_channel *ctch = &ct->host_channel; + + ctch_fini(guc, ctch); +} + +/** + * intel_guc_ct_enable - Enable buffer based command transport. + * @ct: pointer to CT struct + * + * Return: 0 on success, a negative errno code on failure. + */ +int intel_guc_ct_enable(struct intel_guc_ct *ct) +{ + struct intel_guc *guc = ct_to_guc(ct); + struct intel_guc_ct_channel *ctch = &ct->host_channel; + + if (ctch->enabled) + return 0; + + return ctch_enable(guc, ctch); +} + +/** + * intel_guc_ct_disable - Disable buffer based command transport. + * @ct: pointer to CT struct + */ +void intel_guc_ct_disable(struct intel_guc_ct *ct) +{ + struct intel_guc *guc = ct_to_guc(ct); + struct intel_guc_ct_channel *ctch = &ct->host_channel; + + if (!ctch->enabled) + return; + + ctch_disable(guc, ctch); +} |