Add the datapath component that manages BOs and submits them to running workloads on the qaic device via the dma_bridge hardware. This allows QAIC clients to interact with their workloads (run inferences) via the following ioctls along with mmap(): DRM_IOCTL_QAIC_CREATE_BO DRM_IOCTL_QAIC_MMAP_BO DRM_IOCTL_QAIC_ATTACH_SLICE_BO DRM_IOCTL_QAIC_EXECUTE_BO DRM_IOCTL_QAIC_PARTIAL_EXECUTE_BO DRM_IOCTL_QAIC_WAIT_BO DRM_IOCTL_QAIC_PERF_STATS_BO Signed-off-by: Jeffrey Hugo <quic_jhugo@xxxxxxxxxxx> Reviewed-by: Carl Vanderlip <quic_carlv@xxxxxxxxxxx> Reviewed-by: Pranjal Ramajor Asha Kanojiya <quic_pkanojiy@xxxxxxxxxxx> Reviewed-by: Stanislaw Gruszka <stanislaw.gruszka@xxxxxxxxxxxxxxx> --- drivers/accel/qaic/qaic_data.c | 1902 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 1902 insertions(+) create mode 100644 drivers/accel/qaic/qaic_data.c diff --git a/drivers/accel/qaic/qaic_data.c b/drivers/accel/qaic/qaic_data.c new file mode 100644 index 0000000..a9cbc79 --- /dev/null +++ b/drivers/accel/qaic/qaic_data.c @@ -0,0 +1,1902 @@ +// SPDX-License-Identifier: GPL-2.0-only + +/* Copyright (c) 2019-2021, The Linux Foundation. All rights reserved. */ +/* Copyright (c) 2021-2023 Qualcomm Innovation Center, Inc. All rights reserved. */ + +#include <linux/bitfield.h> +#include <linux/bits.h> +#include <linux/completion.h> +#include <linux/delay.h> +#include <linux/dma-buf.h> +#include <linux/dma-mapping.h> +#include <linux/interrupt.h> +#include <linux/kref.h> +#include <linux/list.h> +#include <linux/mm.h> +#include <linux/moduleparam.h> +#include <linux/scatterlist.h> +#include <linux/spinlock.h> +#include <linux/srcu.h> +#include <linux/types.h> +#include <linux/uaccess.h> +#include <linux/wait.h> +#include <drm/drm_file.h> +#include <drm/drm_gem.h> +#include <drm/drm_print.h> +#include <uapi/drm/qaic_accel.h> + +#include "qaic.h" + +#define SEM_VAL_MASK GENMASK_ULL(11, 0) +#define SEM_INDEX_MASK GENMASK_ULL(4, 0) +#define BULK_XFER BIT(3) +#define GEN_COMPLETION BIT(4) +#define INBOUND_XFER 1 +#define OUTBOUND_XFER 2 +#define REQHP_OFF 0x0 /* we read this */ +#define REQTP_OFF 0x4 /* we write this */ +#define RSPHP_OFF 0x8 /* we write this */ +#define RSPTP_OFF 0xc /* we read this */ + +#define ENCODE_SEM(val, index, sync, cmd, flags) \ + ({ \ + FIELD_PREP(GENMASK(11, 0), (val)) | \ + FIELD_PREP(GENMASK(20, 16), (index)) | \ + FIELD_PREP(BIT(22), (sync)) | \ + FIELD_PREP(GENMASK(26, 24), (cmd)) | \ + FIELD_PREP(GENMASK(30, 29), (flags)) | \ + FIELD_PREP(BIT(31), (cmd) ? 1 : 0); \ + }) +#define NUM_EVENTS 128 +#define NUM_DELAYS 10 + +static unsigned int wait_exec_default_timeout_ms = 5000; /* 5 sec default */ +module_param(wait_exec_default_timeout_ms, uint, 0600); +MODULE_PARM_DESC(wait_exec_default_timeout_ms, "Default timeout for DRM_IOCTL_QAIC_WAIT_BO"); + +static unsigned int datapath_poll_interval_us = 100; /* 100 usec default */ +module_param(datapath_poll_interval_us, uint, 0600); +MODULE_PARM_DESC(datapath_poll_interval_us, + "Amount of time to sleep between activity when datapath polling is enabled"); + +struct dbc_req { + /* + * A request ID is assigned to each memory handle going in DMA queue. + * As a single memory handle can enqueue multiple elements in DMA queue + * all of them will have the same request ID. + */ + __le16 req_id; + /* Future use */ + __u8 seq_id; + /* + * Special encoded variable + * 7 0 - Do not force to generate MSI after DMA is completed + * 1 - Force to generate MSI after DMA is completed + * 6:5 Reserved + * 4 1 - Generate completion element in the response queue + * 0 - No Completion Code + * 3 0 - DMA request is a Link list transfer + * 1 - DMA request is a Bulk transfer + * 2 Reserved + * 1:0 00 - No DMA transfer involved + * 01 - DMA transfer is part of inbound transfer + * 10 - DMA transfer has outbound transfer + * 11 - NA + */ + __u8 cmd; + __le32 resv; + /* Source address for the transfer */ + __le64 src_addr; + /* Destination address for the transfer */ + __le64 dest_addr; + /* Length of transfer request */ + __le32 len; + __le32 resv2; + /* Doorbell address */ + __le64 db_addr; + /* + * Special encoded variable + * 7 1 - Doorbell(db) write + * 0 - No doorbell write + * 6:2 Reserved + * 1:0 00 - 32 bit access, db address must be aligned to 32bit-boundary + * 01 - 16 bit access, db address must be aligned to 16bit-boundary + * 10 - 8 bit access, db address must be aligned to 8bit-boundary + * 11 - Reserved + */ + __u8 db_len; + __u8 resv3; + __le16 resv4; + /* 32 bit data written to doorbell address */ + __le32 db_data; + /* + * Special encoded variable + * All the fields of sem_cmdX are passed from user and all are ORed + * together to form sem_cmd. + * 0:11 Semaphore value + * 15:12 Reserved + * 20:16 Semaphore index + * 21 Reserved + * 22 Semaphore Sync + * 23 Reserved + * 26:24 Semaphore command + * 28:27 Reserved + * 29 Semaphore DMA out bound sync fence + * 30 Semaphore DMA in bound sync fence + * 31 Enable semaphore command + */ + __le32 sem_cmd0; + __le32 sem_cmd1; + __le32 sem_cmd2; + __le32 sem_cmd3; +} __packed; + +struct dbc_rsp { + /* Request ID of the memory handle whose DMA transaction is completed */ + __le16 req_id; + /* Status of the DMA transaction. 0 : Success otherwise failure */ + __le16 status; +} __packed; + +inline int get_dbc_req_elem_size(void) +{ + return sizeof(struct dbc_req); +} + +inline int get_dbc_rsp_elem_size(void) +{ + return sizeof(struct dbc_rsp); +} + +static void free_slice(struct kref *kref) +{ + struct bo_slice *slice = container_of(kref, struct bo_slice, ref_count); + + list_del(&slice->slice); + drm_gem_object_put(&slice->bo->base); + sg_free_table(slice->sgt); + kfree(slice->sgt); + kfree(slice->reqs); + kfree(slice); +} + +static int clone_range_of_sgt_for_slice(struct qaic_device *qdev, struct sg_table **sgt_out, + struct sg_table *sgt_in, u64 size, u64 offset) +{ + int total_len, len, nents, offf = 0, offl = 0; + struct scatterlist *sg, *sgn, *sgf, *sgl; + struct sg_table *sgt; + int ret, j; + + /* find out number of relevant nents needed for this mem */ + total_len = 0; + sgf = NULL; + sgl = NULL; + nents = 0; + + size = size ? size : PAGE_SIZE; + for (sg = sgt_in->sgl; sg; sg = sg_next(sg)) { + len = sg_dma_len(sg); + + if (!len) + continue; + if (offset >= total_len && offset < total_len + len) { + sgf = sg; + offf = offset - total_len; + } + if (sgf) + nents++; + if (offset + size >= total_len && + offset + size <= total_len + len) { + sgl = sg; + offl = offset + size - total_len; + break; + } + total_len += len; + } + + if (!sgf || !sgl) { + ret = -EINVAL; + goto out; + } + + sgt = kzalloc(sizeof(*sgt), GFP_KERNEL); + if (!sgt) { + ret = -ENOMEM; + goto out; + } + + ret = sg_alloc_table(sgt, nents, GFP_KERNEL); + if (ret) + goto free_sgt; + + /* copy relevant sg node and fix page and length */ + sgn = sgf; + for_each_sgtable_sg(sgt, sg, j) { + memcpy(sg, sgn, sizeof(*sg)); + if (sgn == sgf) { + sg_dma_address(sg) += offf; + sg_dma_len(sg) -= offf; + sg_set_page(sg, sg_page(sgn), sg_dma_len(sg), offf); + } else { + offf = 0; + } + if (sgn == sgl) { + sg_dma_len(sg) = offl - offf; + sg_set_page(sg, sg_page(sgn), offl - offf, offf); + sg_mark_end(sg); + break; + } + sgn = sg_next(sgn); + } + + *sgt_out = sgt; + return ret; + +free_sgt: + kfree(sgt); +out: + *sgt_out = NULL; + return ret; +} + +static int encode_reqs(struct qaic_device *qdev, struct bo_slice *slice, + struct qaic_attach_slice_entry *req) +{ + __le64 db_addr = cpu_to_le64(req->db_addr); + __le32 db_data = cpu_to_le32(req->db_data); + struct scatterlist *sg; + __u8 cmd = BULK_XFER; + int presync_sem; + u64 dev_addr; + __u8 db_len; + int i; + + if (!slice->no_xfer) + cmd |= (slice->dir == DMA_TO_DEVICE ? INBOUND_XFER : OUTBOUND_XFER); + + if (req->db_len && !IS_ALIGNED(req->db_addr, req->db_len / 8)) + return -EINVAL; + + presync_sem = req->sem0.presync + req->sem1.presync + req->sem2.presync + req->sem3.presync; + if (presync_sem > 1) + return -EINVAL; + + presync_sem = req->sem0.presync << 0 | req->sem1.presync << 1 | + req->sem2.presync << 2 | req->sem3.presync << 3; + + switch (req->db_len) { + case 32: + db_len = BIT(7); + break; + case 16: + db_len = BIT(7) | 1; + break; + case 8: + db_len = BIT(7) | 2; + break; + case 0: + db_len = 0; /* doorbell is not active for this command */ + break; + default: + return -EINVAL; /* should never hit this */ + } + + /* + * When we end up splitting up a single request (ie a buf slice) into + * multiple DMA requests, we have to manage the sync data carefully. + * There can only be one presync sem. That needs to be on every xfer + * so that the DMA engine doesn't transfer data before the receiver is + * ready. We only do the doorbell and postsync sems after the xfer. + * To guarantee previous xfers for the request are complete, we use a + * fence. + */ + dev_addr = req->dev_addr; + for_each_sgtable_sg(slice->sgt, sg, i) { + slice->reqs[i].cmd = cmd; + slice->reqs[i].src_addr = cpu_to_le64(slice->dir == DMA_TO_DEVICE ? + sg_dma_address(sg) : dev_addr); + slice->reqs[i].dest_addr = cpu_to_le64(slice->dir == DMA_TO_DEVICE ? + dev_addr : sg_dma_address(sg)); + /* + * sg_dma_len(sg) returns size of a DMA segment, maximum DMA + * segment size is set to UINT_MAX by qaic and hence return + * values of sg_dma_len(sg) can never exceed u32 range. So, + * by down sizing we are not corrupting the value. + */ + slice->reqs[i].len = cpu_to_le32((u32)sg_dma_len(sg)); + switch (presync_sem) { + case BIT(0): + slice->reqs[i].sem_cmd0 = cpu_to_le32(ENCODE_SEM(req->sem0.val, + req->sem0.index, + req->sem0.presync, + req->sem0.cmd, + req->sem0.flags)); + break; + case BIT(1): + slice->reqs[i].sem_cmd1 = cpu_to_le32(ENCODE_SEM(req->sem1.val, + req->sem1.index, + req->sem1.presync, + req->sem1.cmd, + req->sem1.flags)); + break; + case BIT(2): + slice->reqs[i].sem_cmd2 = cpu_to_le32(ENCODE_SEM(req->sem2.val, + req->sem2.index, + req->sem2.presync, + req->sem2.cmd, + req->sem2.flags)); + break; + case BIT(3): + slice->reqs[i].sem_cmd3 = cpu_to_le32(ENCODE_SEM(req->sem3.val, + req->sem3.index, + req->sem3.presync, + req->sem3.cmd, + req->sem3.flags)); + break; + } + dev_addr += sg_dma_len(sg); + } + /* add post transfer stuff to last segment */ + i--; + slice->reqs[i].cmd |= GEN_COMPLETION; + slice->reqs[i].db_addr = db_addr; + slice->reqs[i].db_len = db_len; + slice->reqs[i].db_data = db_data; + /* + * Add a fence if we have more than one request going to the hardware + * representing the entirety of the user request, and the user request + * has no presync condition. + * Fences are expensive, so we try to avoid them. We rely on the + * hardware behavior to avoid needing one when there is a presync + * condition. When a presync exists, all requests for that same + * presync will be queued into a fifo. Thus, since we queue the + * post xfer activity only on the last request we queue, the hardware + * will ensure that the last queued request is processed last, thus + * making sure the post xfer activity happens at the right time without + * a fence. + */ + if (i && !presync_sem) + req->sem0.flags |= (slice->dir == DMA_TO_DEVICE ? + QAIC_SEM_INSYNCFENCE : QAIC_SEM_OUTSYNCFENCE); + slice->reqs[i].sem_cmd0 = cpu_to_le32(ENCODE_SEM(req->sem0.val, req->sem0.index, + req->sem0.presync, req->sem0.cmd, + req->sem0.flags)); + slice->reqs[i].sem_cmd1 = cpu_to_le32(ENCODE_SEM(req->sem1.val, req->sem1.index, + req->sem1.presync, req->sem1.cmd, + req->sem1.flags)); + slice->reqs[i].sem_cmd2 = cpu_to_le32(ENCODE_SEM(req->sem2.val, req->sem2.index, + req->sem2.presync, req->sem2.cmd, + req->sem2.flags)); + slice->reqs[i].sem_cmd3 = cpu_to_le32(ENCODE_SEM(req->sem3.val, req->sem3.index, + req->sem3.presync, req->sem3.cmd, + req->sem3.flags)); + + return 0; +} + +static int qaic_map_one_slice(struct qaic_device *qdev, struct qaic_bo *bo, + struct qaic_attach_slice_entry *slice_ent) +{ + struct sg_table *sgt = NULL; + struct bo_slice *slice; + int ret; + + ret = clone_range_of_sgt_for_slice(qdev, &sgt, bo->sgt, slice_ent->size, slice_ent->offset); + if (ret) + goto out; + + slice = kmalloc(sizeof(*slice), GFP_KERNEL); + if (!slice) { + ret = -ENOMEM; + goto free_sgt; + } + + slice->reqs = kcalloc(sgt->nents, sizeof(*slice->reqs), GFP_KERNEL); + if (!slice->reqs) { + ret = -ENOMEM; + goto free_slice; + } + + slice->no_xfer = !slice_ent->size; + slice->sgt = sgt; + slice->nents = sgt->nents; + slice->dir = bo->dir; + slice->bo = bo; + slice->size = slice_ent->size; + slice->offset = slice_ent->offset; + + ret = encode_reqs(qdev, slice, slice_ent); + if (ret) + goto free_req; + + bo->total_slice_nents += sgt->nents; + kref_init(&slice->ref_count); + drm_gem_object_get(&bo->base); + list_add_tail(&slice->slice, &bo->slices); + + return 0; + +free_req: + kfree(slice->reqs); +free_slice: + kfree(slice); +free_sgt: + sg_free_table(sgt); + kfree(sgt); +out: + return ret; +} + +static int create_sgt(struct qaic_device *qdev, struct sg_table **sgt_out, u64 size) +{ + struct scatterlist *sg; + struct sg_table *sgt; + struct page **pages; + int *pages_order; + int buf_extra; + int max_order; + int nr_pages; + int ret = 0; + int i, j, k; + int order; + + if (size) { + nr_pages = DIV_ROUND_UP(size, PAGE_SIZE); + /* + * calculate how much extra we are going to allocate, to remove + * later + */ + buf_extra = (PAGE_SIZE - size % PAGE_SIZE) % PAGE_SIZE; + max_order = min(MAX_ORDER - 1, get_order(size)); + } else { + /* allocate a single page for book keeping */ + nr_pages = 1; + buf_extra = 0; + max_order = 0; + } + + pages = kvmalloc_array(nr_pages, sizeof(*pages) + sizeof(*pages_order), GFP_KERNEL); + if (!pages) { + ret = -ENOMEM; + goto out; + } + pages_order = (void *)pages + sizeof(*pages) * nr_pages; + + /* + * Allocate requested memory using alloc_pages. It is possible to allocate + * the requested memory in multiple chunks by calling alloc_pages + * multiple times. Use SG table to handle multiple allocated pages. + */ + i = 0; + while (nr_pages > 0) { + order = min(get_order(nr_pages * PAGE_SIZE), max_order); + while (1) { + pages[i] = alloc_pages(GFP_KERNEL | GFP_HIGHUSER | + __GFP_NOWARN | __GFP_ZERO | + (order ? __GFP_NORETRY : __GFP_RETRY_MAYFAIL), + order); + if (pages[i]) + break; + if (!order--) { + ret = -ENOMEM; + goto free_partial_alloc; + } + } + + max_order = order; + pages_order[i] = order; + + nr_pages -= 1 << order; + if (nr_pages <= 0) + /* account for over allocation */ + buf_extra += abs(nr_pages) * PAGE_SIZE; + i++; + } + + sgt = kmalloc(sizeof(*sgt), GFP_KERNEL); + if (!sgt) { + ret = -ENOMEM; + goto free_partial_alloc; + } + + if (sg_alloc_table(sgt, i, GFP_KERNEL)) { + ret = -ENOMEM; + goto free_sgt; + } + + /* Populate the SG table with the allocated memory pages */ + sg = sgt->sgl; + for (k = 0; k < i; k++, sg = sg_next(sg)) { + /* Last entry requires special handling */ + if (k < i - 1) { + sg_set_page(sg, pages[k], PAGE_SIZE << pages_order[k], 0); + } else { + sg_set_page(sg, pages[k], (PAGE_SIZE << pages_order[k]) - buf_extra, 0); + sg_mark_end(sg); + } + + } + + kvfree(pages); + *sgt_out = sgt; + return ret; + +free_sgt: + kfree(sgt); +free_partial_alloc: + for (j = 0; j < i; j++) + __free_pages(pages[j], pages_order[j]); + kvfree(pages); +out: + *sgt_out = NULL; + return ret; +} + +static bool invalid_sem(struct qaic_sem *sem) +{ + if (sem->val & ~SEM_VAL_MASK || sem->index & ~SEM_INDEX_MASK || + !(sem->presync == 0 || sem->presync == 1) || sem->pad || + sem->flags & ~(QAIC_SEM_INSYNCFENCE | QAIC_SEM_OUTSYNCFENCE) || + sem->cmd > QAIC_SEM_WAIT_GT_0) + return true; + return false; +} + +static int qaic_validate_req(struct qaic_device *qdev, struct qaic_attach_slice_entry *slice_ent, + u32 count, u64 total_size) +{ + int i; + + for (i = 0; i < count; i++) { + if (!(slice_ent[i].db_len == 32 || slice_ent[i].db_len == 16 || + slice_ent[i].db_len == 8 || slice_ent[i].db_len == 0) || + invalid_sem(&slice_ent[i].sem0) || invalid_sem(&slice_ent[i].sem1) || + invalid_sem(&slice_ent[i].sem2) || invalid_sem(&slice_ent[i].sem3)) + return -EINVAL; + + if (slice_ent[i].offset + slice_ent[i].size > total_size) + return -EINVAL; + } + + return 0; +} + +static void qaic_free_sgt(struct sg_table *sgt) +{ + struct scatterlist *sg; + + for (sg = sgt->sgl; sg; sg = sg_next(sg)) + if (sg_page(sg)) + __free_pages(sg_page(sg), get_order(sg->length)); + sg_free_table(sgt); + kfree(sgt); +} + +static void qaic_gem_print_info(struct drm_printer *p, unsigned int indent, + const struct drm_gem_object *obj) +{ + struct qaic_bo *bo = to_qaic_bo(obj); + + drm_printf_indent(p, indent, "user requested size=%llu\n", bo->size); +} + +static const struct vm_operations_struct drm_vm_ops = { + .open = drm_gem_vm_open, + .close = drm_gem_vm_close, +}; + +static int qaic_gem_object_mmap(struct drm_gem_object *obj, struct vm_area_struct *vma) +{ + struct qaic_bo *bo = to_qaic_bo(obj); + unsigned long offset = 0; + struct scatterlist *sg; + int ret; + + if (obj->import_attach) + return -EINVAL; + + for (sg = bo->sgt->sgl; sg; sg = sg_next(sg)) { + if (sg_page(sg)) { + ret = remap_pfn_range(vma, vma->vm_start + offset, page_to_pfn(sg_page(sg)), + sg->length, vma->vm_page_prot); + if (ret) + goto out; + offset += sg->length; + } + } + +out: + return ret; +} + +static void qaic_free_object(struct drm_gem_object *obj) +{ + struct qaic_bo *bo = to_qaic_bo(obj); + + if (obj->import_attach) { + /* DMABUF/PRIME Path */ + dma_buf_detach(obj->import_attach->dmabuf, obj->import_attach); + dma_buf_put(obj->import_attach->dmabuf); + } else { + /* Private buffer allocation path */ + qaic_free_sgt(bo->sgt); + } + + drm_gem_object_release(obj); + kfree(bo); +} + +static const struct drm_gem_object_funcs qaic_gem_funcs = { + .free = qaic_free_object, + .print_info = qaic_gem_print_info, + .mmap = qaic_gem_object_mmap, + .vm_ops = &drm_vm_ops, +}; + +static struct qaic_bo *qaic_alloc_init_bo(void) +{ + struct qaic_bo *bo; + + bo = kzalloc(sizeof(*bo), GFP_KERNEL); + if (!bo) + return ERR_PTR(-ENOMEM); + + INIT_LIST_HEAD(&bo->slices); + init_completion(&bo->xfer_done); + complete_all(&bo->xfer_done); + + return bo; +} + +int qaic_create_bo_ioctl(struct drm_device *dev, void *data, struct drm_file *file_priv) +{ + struct qaic_create_bo *args = data; + int usr_rcu_id, qdev_rcu_id; + struct drm_gem_object *obj; + struct qaic_device *qdev; + struct qaic_user *usr; + struct qaic_bo *bo; + size_t size; + int ret; + + if (args->pad) + return -EINVAL; + + usr = file_priv->driver_priv; + usr_rcu_id = srcu_read_lock(&usr->qddev_lock); + if (!usr->qddev) { + ret = -ENODEV; + goto unlock_usr_srcu; + } + + qdev = usr->qddev->qdev; + qdev_rcu_id = srcu_read_lock(&qdev->dev_lock); + if (qdev->in_reset) { + ret = -ENODEV; + goto unlock_dev_srcu; + } + + size = PAGE_ALIGN(args->size); + if (size == 0) { + ret = -EINVAL; + goto unlock_dev_srcu; + } + + bo = qaic_alloc_init_bo(); + if (IS_ERR(bo)) { + ret = PTR_ERR(bo); + goto unlock_dev_srcu; + } + obj = &bo->base; + + drm_gem_private_object_init(dev, obj, size); + + obj->funcs = &qaic_gem_funcs; + ret = create_sgt(qdev, &bo->sgt, size); + if (ret) + goto free_bo; + + bo->size = args->size; + + ret = drm_gem_handle_create(file_priv, obj, &args->handle); + if (ret) + goto free_sgt; + + bo->handle = args->handle; + drm_gem_object_put(obj); + srcu_read_unlock(&qdev->dev_lock, qdev_rcu_id); + srcu_read_unlock(&usr->qddev_lock, usr_rcu_id); + + return 0; + +free_sgt: + qaic_free_sgt(bo->sgt); +free_bo: + kfree(bo); +unlock_dev_srcu: + srcu_read_unlock(&qdev->dev_lock, qdev_rcu_id); +unlock_usr_srcu: + srcu_read_unlock(&usr->qddev_lock, usr_rcu_id); + return ret; +} + +int qaic_mmap_bo_ioctl(struct drm_device *dev, void *data, struct drm_file *file_priv) +{ + struct qaic_mmap_bo *args = data; + int usr_rcu_id, qdev_rcu_id; + struct drm_gem_object *obj; + struct qaic_device *qdev; + struct qaic_user *usr; + int ret; + + usr = file_priv->driver_priv; + usr_rcu_id = srcu_read_lock(&usr->qddev_lock); + if (!usr->qddev) { + ret = -ENODEV; + goto unlock_usr_srcu; + } + + qdev = usr->qddev->qdev; + qdev_rcu_id = srcu_read_lock(&qdev->dev_lock); + if (qdev->in_reset) { + ret = -ENODEV; + goto unlock_dev_srcu; + } + + obj = drm_gem_object_lookup(file_priv, args->handle); + if (!obj) { + ret = -ENOENT; + goto unlock_dev_srcu; + } + + ret = drm_gem_create_mmap_offset(obj); + if (ret == 0) + args->offset = drm_vma_node_offset_addr(&obj->vma_node); + + drm_gem_object_put(obj); + +unlock_dev_srcu: + srcu_read_unlock(&qdev->dev_lock, qdev_rcu_id); +unlock_usr_srcu: + srcu_read_unlock(&usr->qddev_lock, usr_rcu_id); + return ret; +} + +struct drm_gem_object *qaic_gem_prime_import(struct drm_device *dev, struct dma_buf *dma_buf) +{ + struct dma_buf_attachment *attach; + struct drm_gem_object *obj; + struct qaic_bo *bo; + size_t size; + int ret; + + bo = qaic_alloc_init_bo(); + if (IS_ERR(bo)) { + ret = PTR_ERR(bo); + goto out; + } + + obj = &bo->base; + get_dma_buf(dma_buf); + + attach = dma_buf_attach(dma_buf, dev->dev); + if (IS_ERR(attach)) { + ret = PTR_ERR(attach); + goto attach_fail; + } + + size = PAGE_ALIGN(attach->dmabuf->size); + if (size == 0) { + ret = -EINVAL; + goto size_align_fail; + } + + drm_gem_private_object_init(dev, obj, size); + /* + * skipping dma_buf_map_attachment() as we do not know the direction + * just yet. Once the direction is known in the subsequent IOCTL to + * attach slicing, we can do it then. + */ + + obj->funcs = &qaic_gem_funcs; + obj->import_attach = attach; + obj->resv = dma_buf->resv; + + return obj; + +size_align_fail: + dma_buf_detach(dma_buf, attach); +attach_fail: + dma_buf_put(dma_buf); + kfree(bo); +out: + return ERR_PTR(ret); +} + +static int qaic_prepare_import_bo(struct qaic_bo *bo, struct qaic_attach_slice_hdr *hdr) +{ + struct drm_gem_object *obj = &bo->base; + struct sg_table *sgt; + int ret; + + if (obj->import_attach->dmabuf->size < hdr->size) + return -EINVAL; + + sgt = dma_buf_map_attachment(obj->import_attach, hdr->dir); + if (IS_ERR(sgt)) { + ret = PTR_ERR(sgt); + return ret; + } + + bo->sgt = sgt; + bo->size = hdr->size; + + return 0; +} + +static int qaic_prepare_export_bo(struct qaic_device *qdev, struct qaic_bo *bo, + struct qaic_attach_slice_hdr *hdr) +{ + int ret; + + if (bo->size != hdr->size) + return -EINVAL; + + ret = dma_map_sgtable(&qdev->pdev->dev, bo->sgt, hdr->dir, 0); + if (ret) + return -EFAULT; + + return 0; +} + +static int qaic_prepare_bo(struct qaic_device *qdev, struct qaic_bo *bo, + struct qaic_attach_slice_hdr *hdr) +{ + int ret; + + if (bo->base.import_attach) + ret = qaic_prepare_import_bo(bo, hdr); + else + ret = qaic_prepare_export_bo(qdev, bo, hdr); + + if (ret == 0) + bo->dir = hdr->dir; + + return ret; +} + +static void qaic_unprepare_import_bo(struct qaic_bo *bo) +{ + dma_buf_unmap_attachment(bo->base.import_attach, bo->sgt, bo->dir); + bo->sgt = NULL; + bo->size = 0; +} + +static void qaic_unprepare_export_bo(struct qaic_device *qdev, struct qaic_bo *bo) +{ + dma_unmap_sgtable(&qdev->pdev->dev, bo->sgt, bo->dir, 0); +} + +static void qaic_unprepare_bo(struct qaic_device *qdev, struct qaic_bo *bo) +{ + if (bo->base.import_attach) + qaic_unprepare_import_bo(bo); + else + qaic_unprepare_export_bo(qdev, bo); + + bo->dir = 0; +} + +static void qaic_free_slices_bo(struct qaic_bo *bo) +{ + struct bo_slice *slice, *temp; + + list_for_each_entry_safe(slice, temp, &bo->slices, slice) + kref_put(&slice->ref_count, free_slice); +} + +static int qaic_attach_slicing_bo(struct qaic_device *qdev, struct qaic_bo *bo, + struct qaic_attach_slice_hdr *hdr, + struct qaic_attach_slice_entry *slice_ent) +{ + int ret, i; + + for (i = 0; i < hdr->count; i++) { + ret = qaic_map_one_slice(qdev, bo, &slice_ent[i]); + if (ret) { + qaic_free_slices_bo(bo); + return ret; + } + } + + if (bo->total_slice_nents > qdev->dbc[hdr->dbc_id].nelem) { + qaic_free_slices_bo(bo); + return -ENOSPC; + } + + bo->sliced = true; + bo->nr_slice = hdr->count; + list_add_tail(&bo->bo_list, &qdev->dbc[hdr->dbc_id].bo_lists); + + return 0; +} + +int qaic_attach_slice_bo_ioctl(struct drm_device *dev, void *data, struct drm_file *file_priv) +{ + struct qaic_attach_slice_entry *slice_ent; + struct qaic_attach_slice *args = data; + struct dma_bridge_chan *dbc; + int usr_rcu_id, qdev_rcu_id; + struct drm_gem_object *obj; + struct qaic_device *qdev; + unsigned long arg_size; + struct qaic_user *usr; + u8 __user *user_data; + struct qaic_bo *bo; + int ret; + + usr = file_priv->driver_priv; + usr_rcu_id = srcu_read_lock(&usr->qddev_lock); + if (!usr->qddev) { + ret = -ENODEV; + goto unlock_usr_srcu; + } + + qdev = usr->qddev->qdev; + qdev_rcu_id = srcu_read_lock(&qdev->dev_lock); + if (qdev->in_reset) { + ret = -ENODEV; + goto unlock_dev_srcu; + } + + if (args->hdr.count == 0) { + ret = -EINVAL; + goto unlock_dev_srcu; + } + + arg_size = args->hdr.count * sizeof(*slice_ent); + if (arg_size / args->hdr.count != sizeof(*slice_ent)) { + ret = -EINVAL; + goto unlock_dev_srcu; + } + + if (args->hdr.dbc_id >= qdev->num_dbc) { + ret = -EINVAL; + goto unlock_dev_srcu; + } + + if (args->hdr.size == 0) { + ret = -EINVAL; + goto unlock_dev_srcu; + } + + if (!(args->hdr.dir == DMA_TO_DEVICE || args->hdr.dir == DMA_FROM_DEVICE)) { + ret = -EINVAL; + goto unlock_dev_srcu; + } + + dbc = &qdev->dbc[args->hdr.dbc_id]; + if (dbc->usr != usr) { + ret = -EINVAL; + goto unlock_dev_srcu; + } + + if (args->data == 0) { + ret = -EINVAL; + goto unlock_dev_srcu; + } + + user_data = u64_to_user_ptr(args->data); + + slice_ent = kzalloc(arg_size, GFP_KERNEL); + if (!slice_ent) { + ret = -EINVAL; + goto unlock_dev_srcu; + } + + ret = copy_from_user(slice_ent, user_data, arg_size); + if (ret) { + ret = -EFAULT; + goto free_slice_ent; + } + + ret = qaic_validate_req(qdev, slice_ent, args->hdr.count, args->hdr.size); + if (ret) + goto free_slice_ent; + + obj = drm_gem_object_lookup(file_priv, args->hdr.handle); + if (!obj) { + ret = -ENOENT; + goto free_slice_ent; + } + + bo = to_qaic_bo(obj); + + ret = qaic_prepare_bo(qdev, bo, &args->hdr); + if (ret) + goto put_bo; + + ret = qaic_attach_slicing_bo(qdev, bo, &args->hdr, slice_ent); + if (ret) + goto unprepare_bo; + + if (args->hdr.dir == DMA_TO_DEVICE) + dma_sync_sgtable_for_cpu(&qdev->pdev->dev, bo->sgt, args->hdr.dir); + + bo->dbc = dbc; + drm_gem_object_put(obj); + srcu_read_unlock(&qdev->dev_lock, qdev_rcu_id); + srcu_read_unlock(&usr->qddev_lock, usr_rcu_id); + + return 0; + +unprepare_bo: + qaic_unprepare_bo(qdev, bo); +put_bo: + drm_gem_object_put(obj); +free_slice_ent: + kfree(slice_ent); +unlock_dev_srcu: + srcu_read_unlock(&qdev->dev_lock, qdev_rcu_id); +unlock_usr_srcu: + srcu_read_unlock(&usr->qddev_lock, usr_rcu_id); + return ret; +} + +static inline int copy_exec_reqs(struct qaic_device *qdev, struct bo_slice *slice, u32 dbc_id, + u32 head, u32 *ptail) +{ + struct dma_bridge_chan *dbc = &qdev->dbc[dbc_id]; + struct dbc_req *reqs = slice->reqs; + u32 tail = *ptail; + u32 avail; + + avail = head - tail; + if (head <= tail) + avail += dbc->nelem; + + --avail; + + if (avail < slice->nents) + return -EAGAIN; + + if (tail + slice->nents > dbc->nelem) { + avail = dbc->nelem - tail; + avail = min_t(u32, avail, slice->nents); + memcpy(dbc->req_q_base + tail * get_dbc_req_elem_size(), reqs, + sizeof(*reqs) * avail); + reqs += avail; + avail = slice->nents - avail; + if (avail) + memcpy(dbc->req_q_base, reqs, sizeof(*reqs) * avail); + } else { + memcpy(dbc->req_q_base + tail * get_dbc_req_elem_size(), reqs, + sizeof(*reqs) * slice->nents); + } + + *ptail = (tail + slice->nents) % dbc->nelem; + + return 0; +} + +/* + * Based on the value of resize we may only need to transmit first_n + * entries and the last entry, with last_bytes to send from the last entry. + * Note that first_n could be 0. + */ +static inline int copy_partial_exec_reqs(struct qaic_device *qdev, struct bo_slice *slice, + u64 resize, u32 dbc_id, u32 head, u32 *ptail) +{ + struct dma_bridge_chan *dbc = &qdev->dbc[dbc_id]; + struct dbc_req *reqs = slice->reqs; + struct dbc_req *last_req; + u32 tail = *ptail; + u64 total_bytes; + u64 last_bytes; + u32 first_n; + u32 avail; + int ret; + int i; + + avail = head - tail; + if (head <= tail) + avail += dbc->nelem; + + --avail; + + total_bytes = 0; + for (i = 0; i < slice->nents; i++) { + total_bytes += le32_to_cpu(reqs[i].len); + if (total_bytes >= resize) + break; + } + + if (total_bytes < resize) { + /* User space should have used the full buffer path. */ + ret = -EINVAL; + return ret; + } + + first_n = i; + last_bytes = i ? resize + le32_to_cpu(reqs[i].len) - total_bytes : resize; + + if (avail < (first_n + 1)) + return -EAGAIN; + + if (first_n) { + if (tail + first_n > dbc->nelem) { + avail = dbc->nelem - tail; + avail = min_t(u32, avail, first_n); + memcpy(dbc->req_q_base + tail * get_dbc_req_elem_size(), reqs, + sizeof(*reqs) * avail); + last_req = reqs + avail; + avail = first_n - avail; + if (avail) + memcpy(dbc->req_q_base, last_req, sizeof(*reqs) * avail); + } else { + memcpy(dbc->req_q_base + tail * get_dbc_req_elem_size(), reqs, + sizeof(*reqs) * first_n); + } + } + + /* Copy over the last entry. Here we need to adjust len to the left over + * size, and set src and dst to the entry it is copied to. + */ + last_req = dbc->req_q_base + (tail + first_n) % dbc->nelem * get_dbc_req_elem_size(); + memcpy(last_req, reqs + slice->nents - 1, sizeof(*reqs)); + + /* + * last_bytes holds size of a DMA segment, maximum DMA segment size is + * set to UINT_MAX by qaic and hence last_bytes can never exceed u32 + * range. So, by down sizing we are not corrupting the value. + */ + last_req->len = cpu_to_le32((u32)last_bytes); + last_req->src_addr = reqs[first_n].src_addr; + last_req->dest_addr = reqs[first_n].dest_addr; + + *ptail = (tail + first_n + 1) % dbc->nelem; + + return 0; +} + +static int send_bo_list_to_device(struct qaic_device *qdev, struct drm_file *file_priv, + struct qaic_execute_entry *exec, unsigned int count, + bool is_partial, struct dma_bridge_chan *dbc, u32 head, + u32 *tail) +{ + struct qaic_partial_execute_entry *pexec = (struct qaic_partial_execute_entry *)exec; + struct drm_gem_object *obj; + struct bo_slice *slice; + unsigned long flags; + struct qaic_bo *bo; + bool queued; + int i, j; + int ret; + + for (i = 0; i < count; i++) { + /* + * ref count will be decremented when the transfer of this + * buffer is complete. It is inside dbc_irq_threaded_fn(). + */ + obj = drm_gem_object_lookup(file_priv, + is_partial ? pexec[i].handle : exec[i].handle); + if (!obj) { + ret = -ENOENT; + goto failed_to_send_bo; + } + + bo = to_qaic_bo(obj); + + if (!bo->sliced) { + ret = -EINVAL; + goto failed_to_send_bo; + } + + if (is_partial && pexec[i].resize > bo->size) { + ret = -EINVAL; + goto failed_to_send_bo; + } + + spin_lock_irqsave(&dbc->xfer_lock, flags); + queued = bo->queued; + bo->queued = true; + if (queued) { + spin_unlock_irqrestore(&dbc->xfer_lock, flags); + ret = -EINVAL; + goto failed_to_send_bo; + } + + bo->req_id = dbc->next_req_id++; + + list_for_each_entry(slice, &bo->slices, slice) { + /* + * If this slice does not fall under the given + * resize then skip this slice and continue the loop + */ + if (is_partial && pexec[i].resize && pexec[i].resize <= slice->offset) + continue; + + for (j = 0; j < slice->nents; j++) + slice->reqs[j].req_id = cpu_to_le16(bo->req_id); + + /* + * If it is a partial execute ioctl call then check if + * resize has cut this slice short then do a partial copy + * else do complete copy + */ + if (is_partial && pexec[i].resize && + pexec[i].resize < slice->offset + slice->size) + ret = copy_partial_exec_reqs(qdev, slice, + pexec[i].resize - slice->offset, + dbc->id, head, tail); + else + ret = copy_exec_reqs(qdev, slice, dbc->id, head, tail); + if (ret) { + bo->queued = false; + spin_unlock_irqrestore(&dbc->xfer_lock, flags); + goto failed_to_send_bo; + } + } + reinit_completion(&bo->xfer_done); + list_add_tail(&bo->xfer_list, &dbc->xfer_list); + spin_unlock_irqrestore(&dbc->xfer_lock, flags); + dma_sync_sgtable_for_device(&qdev->pdev->dev, bo->sgt, bo->dir); + } + + return 0; + +failed_to_send_bo: + if (likely(obj)) + drm_gem_object_put(obj); + for (j = 0; j < i; j++) { + spin_lock_irqsave(&dbc->xfer_lock, flags); + bo = list_last_entry(&dbc->xfer_list, struct qaic_bo, xfer_list); + obj = &bo->base; + bo->queued = false; + list_del(&bo->xfer_list); + spin_unlock_irqrestore(&dbc->xfer_lock, flags); + dma_sync_sgtable_for_cpu(&qdev->pdev->dev, bo->sgt, bo->dir); + drm_gem_object_put(obj); + } + return ret; +} + +static void update_profiling_data(struct drm_file *file_priv, + struct qaic_execute_entry *exec, unsigned int count, + bool is_partial, u64 received_ts, u64 submit_ts, u32 queue_level) +{ + struct qaic_partial_execute_entry *pexec = (struct qaic_partial_execute_entry *)exec; + struct drm_gem_object *obj; + struct qaic_bo *bo; + int i; + + for (i = 0; i < count; i++) { + /* + * Since we already committed the BO to hardware, the only way + * this should fail is a pending signal. We can't cancel the + * submit to hardware, so we have to just skip the profiling + * data. In case the signal is not fatal to the process, we + * return success so that the user doesn't try to resubmit. + */ + obj = drm_gem_object_lookup(file_priv, + is_partial ? pexec[i].handle : exec[i].handle); + if (!obj) + break; + bo = to_qaic_bo(obj); + bo->perf_stats.req_received_ts = received_ts; + bo->perf_stats.req_submit_ts = submit_ts; + bo->perf_stats.queue_level_before = queue_level; + queue_level += bo->total_slice_nents; + drm_gem_object_put(obj); + } +} + +static int __qaic_execute_bo_ioctl(struct drm_device *dev, void *data, struct drm_file *file_priv, + bool is_partial) +{ + struct qaic_partial_execute_entry *pexec; + struct qaic_execute *args = data; + struct qaic_execute_entry *exec; + struct dma_bridge_chan *dbc; + int usr_rcu_id, qdev_rcu_id; + struct qaic_device *qdev; + struct qaic_user *usr; + u8 __user *user_data; + unsigned long n; + u64 received_ts; + u32 queue_level; + u64 submit_ts; + int rcu_id; + u32 head; + u32 tail; + u64 size; + int ret; + + received_ts = ktime_get_ns(); + + size = is_partial ? sizeof(*pexec) : sizeof(*exec); + + n = (unsigned long)size * args->hdr.count; + if (args->hdr.count == 0 || n / args->hdr.count != size) + return -EINVAL; + + user_data = u64_to_user_ptr(args->data); + + exec = kcalloc(args->hdr.count, size, GFP_KERNEL); + pexec = (struct qaic_partial_execute_entry *)exec; + if (!exec) + return -ENOMEM; + + if (copy_from_user(exec, user_data, n)) { + ret = -EFAULT; + goto free_exec; + } + + usr = file_priv->driver_priv; + usr_rcu_id = srcu_read_lock(&usr->qddev_lock); + if (!usr->qddev) { + ret = -ENODEV; + goto unlock_usr_srcu; + } + + qdev = usr->qddev->qdev; + qdev_rcu_id = srcu_read_lock(&qdev->dev_lock); + if (qdev->in_reset) { + ret = -ENODEV; + goto unlock_dev_srcu; + } + + if (args->hdr.dbc_id >= qdev->num_dbc) { + ret = -EINVAL; + goto unlock_dev_srcu; + } + + dbc = &qdev->dbc[args->hdr.dbc_id]; + + rcu_id = srcu_read_lock(&dbc->ch_lock); + if (!dbc->usr || dbc->usr->handle != usr->handle) { + ret = -EPERM; + goto release_ch_rcu; + } + + head = readl(dbc->dbc_base + REQHP_OFF); + tail = readl(dbc->dbc_base + REQTP_OFF); + + if (head == U32_MAX || tail == U32_MAX) { + /* PCI link error */ + ret = -ENODEV; + goto release_ch_rcu; + } + + queue_level = head <= tail ? tail - head : dbc->nelem - (head - tail); + + ret = send_bo_list_to_device(qdev, file_priv, exec, args->hdr.count, is_partial, dbc, + head, &tail); + if (ret) + goto release_ch_rcu; + + /* Finalize commit to hardware */ + submit_ts = ktime_get_ns(); + writel(tail, dbc->dbc_base + REQTP_OFF); + + update_profiling_data(file_priv, exec, args->hdr.count, is_partial, received_ts, + submit_ts, queue_level); + + if (datapath_polling) + schedule_work(&dbc->poll_work); + +release_ch_rcu: + srcu_read_unlock(&dbc->ch_lock, rcu_id); +unlock_dev_srcu: + srcu_read_unlock(&qdev->dev_lock, qdev_rcu_id); +unlock_usr_srcu: + srcu_read_unlock(&usr->qddev_lock, usr_rcu_id); +free_exec: + kfree(exec); + return ret; +} + +int qaic_execute_bo_ioctl(struct drm_device *dev, void *data, struct drm_file *file_priv) +{ + return __qaic_execute_bo_ioctl(dev, data, file_priv, false); +} + +int qaic_partial_execute_bo_ioctl(struct drm_device *dev, void *data, struct drm_file *file_priv) +{ + return __qaic_execute_bo_ioctl(dev, data, file_priv, true); +} + +/* + * Our interrupt handling is a bit more complicated than a simple ideal, but + * sadly necessary. + * + * Each dbc has a completion queue. Entries in the queue correspond to DMA + * requests which the device has processed. The hardware already has a built + * in irq mitigation. When the device puts an entry into the queue, it will + * only trigger an interrupt if the queue was empty. Therefore, when adding + * the Nth event to a non-empty queue, the hardware doesn't trigger an + * interrupt. This means the host doesn't get additional interrupts signaling + * the same thing - the queue has something to process. + * This behavior can be overridden in the DMA request. + * This means that when the host receives an interrupt, it is required to + * drain the queue. + * + * This behavior is what NAPI attempts to accomplish, although we can't use + * NAPI as we don't have a netdev. We use threaded irqs instead. + * + * However, there is a situation where the host drains the queue fast enough + * that every event causes an interrupt. Typically this is not a problem as + * the rate of events would be low. However, that is not the case with + * lprnet for example. On an Intel Xeon D-2191 where we run 8 instances of + * lprnet, the host receives roughly 80k interrupts per second from the device + * (per /proc/interrupts). While NAPI documentation indicates the host should + * just chug along, sadly that behavior causes instability in some hosts. + * + * Therefore, we implement an interrupt disable scheme similar to NAPI. The + * key difference is that we will delay after draining the queue for a small + * time to allow additional events to come in via polling. Using the above + * lprnet workload, this reduces the number of interrupts processed from + * ~80k/sec to about 64 in 5 minutes and appears to solve the system + * instability. + */ +irqreturn_t dbc_irq_handler(int irq, void *data) +{ + struct dma_bridge_chan *dbc = data; + int rcu_id; + u32 head; + u32 tail; + + rcu_id = srcu_read_lock(&dbc->ch_lock); + + if (!dbc->usr) { + srcu_read_unlock(&dbc->ch_lock, rcu_id); + return IRQ_HANDLED; + } + + head = readl(dbc->dbc_base + RSPHP_OFF); + if (head == U32_MAX) { /* PCI link error */ + srcu_read_unlock(&dbc->ch_lock, rcu_id); + return IRQ_NONE; + } + + tail = readl(dbc->dbc_base + RSPTP_OFF); + if (tail == U32_MAX) { /* PCI link error */ + srcu_read_unlock(&dbc->ch_lock, rcu_id); + return IRQ_NONE; + } + + if (head == tail) { /* queue empty */ + srcu_read_unlock(&dbc->ch_lock, rcu_id); + return IRQ_NONE; + } + + disable_irq_nosync(irq); + srcu_read_unlock(&dbc->ch_lock, rcu_id); + return IRQ_WAKE_THREAD; +} + +void irq_polling_work(struct work_struct *work) +{ + struct dma_bridge_chan *dbc = container_of(work, struct dma_bridge_chan, poll_work); + unsigned long flags; + int rcu_id; + u32 head; + u32 tail; + + rcu_id = srcu_read_lock(&dbc->ch_lock); + + while (1) { + if (dbc->qdev->in_reset) { + srcu_read_unlock(&dbc->ch_lock, rcu_id); + return; + } + if (!dbc->usr) { + srcu_read_unlock(&dbc->ch_lock, rcu_id); + return; + } + spin_lock_irqsave(&dbc->xfer_lock, flags); + if (list_empty(&dbc->xfer_list)) { + spin_unlock_irqrestore(&dbc->xfer_lock, flags); + srcu_read_unlock(&dbc->ch_lock, rcu_id); + return; + } + spin_unlock_irqrestore(&dbc->xfer_lock, flags); + + head = readl(dbc->dbc_base + RSPHP_OFF); + if (head == U32_MAX) { /* PCI link error */ + srcu_read_unlock(&dbc->ch_lock, rcu_id); + return; + } + + tail = readl(dbc->dbc_base + RSPTP_OFF); + if (tail == U32_MAX) { /* PCI link error */ + srcu_read_unlock(&dbc->ch_lock, rcu_id); + return; + } + + if (head != tail) { + irq_wake_thread(dbc->irq, dbc); + srcu_read_unlock(&dbc->ch_lock, rcu_id); + return; + } + + cond_resched(); + usleep_range(datapath_poll_interval_us, 2 * datapath_poll_interval_us); + } +} + +irqreturn_t dbc_irq_threaded_fn(int irq, void *data) +{ + struct dma_bridge_chan *dbc = data; + int event_count = NUM_EVENTS; + int delay_count = NUM_DELAYS; + struct qaic_device *qdev; + struct qaic_bo *bo, *i; + struct dbc_rsp *rsp; + unsigned long flags; + int rcu_id; + u16 status; + u16 req_id; + u32 head; + u32 tail; + + rcu_id = srcu_read_lock(&dbc->ch_lock); + + head = readl(dbc->dbc_base + RSPHP_OFF); + if (head == U32_MAX) /* PCI link error */ + goto error_out; + + qdev = dbc->qdev; +read_fifo: + + if (!event_count) { + event_count = NUM_EVENTS; + cond_resched(); + } + + /* + * if this channel isn't assigned or gets unassigned during processing + * we have nothing further to do + */ + if (!dbc->usr) + goto error_out; + + tail = readl(dbc->dbc_base + RSPTP_OFF); + if (tail == U32_MAX) /* PCI link error */ + goto error_out; + + if (head == tail) { /* queue empty */ + if (delay_count) { + --delay_count; + usleep_range(100, 200); + goto read_fifo; /* check for a new event */ + } + goto normal_out; + } + + delay_count = NUM_DELAYS; + while (head != tail) { + if (!event_count) + break; + --event_count; + rsp = dbc->rsp_q_base + head * sizeof(*rsp); + req_id = le16_to_cpu(rsp->req_id); + status = le16_to_cpu(rsp->status); + if (status) + pci_dbg(qdev->pdev, "req_id %d failed with status %d\n", req_id, status); + spin_lock_irqsave(&dbc->xfer_lock, flags); + /* + * A BO can receive multiple interrupts, since a BO can be + * divided into multiple slices and a buffer receives as many + * interrupts as slices. So until it receives interrupts for + * all the slices we cannot mark that buffer complete. + */ + list_for_each_entry_safe(bo, i, &dbc->xfer_list, xfer_list) { + if (bo->req_id == req_id) + bo->nr_slice_xfer_done++; + else + continue; + + if (bo->nr_slice_xfer_done < bo->nr_slice) + break; + + /* + * At this point we have received all the interrupts for + * BO, which means BO execution is complete. + */ + dma_sync_sgtable_for_cpu(&qdev->pdev->dev, bo->sgt, bo->dir); + bo->nr_slice_xfer_done = 0; + bo->queued = false; + list_del(&bo->xfer_list); + bo->perf_stats.req_processed_ts = ktime_get_ns(); + complete_all(&bo->xfer_done); + drm_gem_object_put(&bo->base); + break; + } + spin_unlock_irqrestore(&dbc->xfer_lock, flags); + head = (head + 1) % dbc->nelem; + } + + /* + * Update the head pointer of response queue and let the device know + * that we have consumed elements from the queue. + */ + writel(head, dbc->dbc_base + RSPHP_OFF); + + /* elements might have been put in the queue while we were processing */ + goto read_fifo; + +normal_out: + if (likely(!datapath_polling)) + enable_irq(irq); + else + schedule_work(&dbc->poll_work); + /* checking the fifo and enabling irqs is a race, missed event check */ + tail = readl(dbc->dbc_base + RSPTP_OFF); + if (tail != U32_MAX && head != tail) { + if (likely(!datapath_polling)) + disable_irq_nosync(irq); + goto read_fifo; + } + srcu_read_unlock(&dbc->ch_lock, rcu_id); + return IRQ_HANDLED; + +error_out: + srcu_read_unlock(&dbc->ch_lock, rcu_id); + if (likely(!datapath_polling)) + enable_irq(irq); + else + schedule_work(&dbc->poll_work); + + return IRQ_HANDLED; +} + +int qaic_wait_bo_ioctl(struct drm_device *dev, void *data, struct drm_file *file_priv) +{ + struct qaic_wait *args = data; + int usr_rcu_id, qdev_rcu_id; + struct dma_bridge_chan *dbc; + struct drm_gem_object *obj; + struct qaic_device *qdev; + unsigned long timeout; + struct qaic_user *usr; + struct qaic_bo *bo; + int rcu_id; + int ret; + + usr = file_priv->driver_priv; + usr_rcu_id = srcu_read_lock(&usr->qddev_lock); + if (!usr->qddev) { + ret = -ENODEV; + goto unlock_usr_srcu; + } + + qdev = usr->qddev->qdev; + qdev_rcu_id = srcu_read_lock(&qdev->dev_lock); + if (qdev->in_reset) { + ret = -ENODEV; + goto unlock_dev_srcu; + } + + if (args->pad != 0) { + ret = -EINVAL; + goto unlock_dev_srcu; + } + + if (args->dbc_id >= qdev->num_dbc) { + ret = -EINVAL; + goto unlock_dev_srcu; + } + + dbc = &qdev->dbc[args->dbc_id]; + + rcu_id = srcu_read_lock(&dbc->ch_lock); + if (dbc->usr != usr) { + ret = -EPERM; + goto unlock_ch_srcu; + } + + obj = drm_gem_object_lookup(file_priv, args->handle); + if (!obj) { + ret = -ENOENT; + goto unlock_ch_srcu; + } + + bo = to_qaic_bo(obj); + timeout = args->timeout ? args->timeout : wait_exec_default_timeout_ms; + timeout = msecs_to_jiffies(timeout); + ret = wait_for_completion_interruptible_timeout(&bo->xfer_done, timeout); + if (!ret) { + ret = -ETIMEDOUT; + goto put_obj; + } + if (ret > 0) + ret = 0; + + if (!dbc->usr) + ret = -EPERM; + +put_obj: + drm_gem_object_put(obj); +unlock_ch_srcu: + srcu_read_unlock(&dbc->ch_lock, rcu_id); +unlock_dev_srcu: + srcu_read_unlock(&qdev->dev_lock, qdev_rcu_id); +unlock_usr_srcu: + srcu_read_unlock(&usr->qddev_lock, usr_rcu_id); + return ret; +} + +int qaic_perf_stats_bo_ioctl(struct drm_device *dev, void *data, struct drm_file *file_priv) +{ + struct qaic_perf_stats_entry *ent = NULL; + struct qaic_perf_stats *args = data; + int usr_rcu_id, qdev_rcu_id; + struct drm_gem_object *obj; + struct qaic_device *qdev; + struct qaic_user *usr; + struct qaic_bo *bo; + int ret, i; + + usr = file_priv->driver_priv; + usr_rcu_id = srcu_read_lock(&usr->qddev_lock); + if (!usr->qddev) { + ret = -ENODEV; + goto unlock_usr_srcu; + } + + qdev = usr->qddev->qdev; + qdev_rcu_id = srcu_read_lock(&qdev->dev_lock); + if (qdev->in_reset) { + ret = -ENODEV; + goto unlock_dev_srcu; + } + + if (args->hdr.dbc_id >= qdev->num_dbc) { + ret = -EINVAL; + goto unlock_dev_srcu; + } + + ent = kcalloc(args->hdr.count, sizeof(*ent), GFP_KERNEL); + if (!ent) { + ret = -EINVAL; + goto unlock_dev_srcu; + } + + ret = copy_from_user(ent, u64_to_user_ptr(args->data), args->hdr.count * sizeof(*ent)); + if (ret) { + ret = -EFAULT; + goto free_ent; + } + + for (i = 0; i < args->hdr.count; i++) { + obj = drm_gem_object_lookup(file_priv, ent[i].handle); + if (!obj) { + ret = -ENOENT; + goto free_ent; + } + bo = to_qaic_bo(obj); + /* + * perf stats ioctl is called before wait ioctl is complete then + * the latency information is invalid. + */ + if (bo->perf_stats.req_processed_ts < bo->perf_stats.req_submit_ts) { + ent[i].device_latency_us = 0; + } else { + ent[i].device_latency_us = (bo->perf_stats.req_processed_ts - + bo->perf_stats.req_submit_ts) / 1000; + } + ent[i].submit_latency_us = (bo->perf_stats.req_submit_ts - + bo->perf_stats.req_received_ts) / 1000; + ent[i].queue_level_before = bo->perf_stats.queue_level_before; + ent[i].num_queue_element = bo->total_slice_nents; + drm_gem_object_put(obj); + } + + if (copy_to_user(u64_to_user_ptr(args->data), ent, args->hdr.count * sizeof(*ent))) + ret = -EFAULT; + +free_ent: + kfree(ent); +unlock_dev_srcu: + srcu_read_unlock(&qdev->dev_lock, qdev_rcu_id); +unlock_usr_srcu: + srcu_read_unlock(&usr->qddev_lock, usr_rcu_id); + return ret; +} + +static void empty_xfer_list(struct qaic_device *qdev, struct dma_bridge_chan *dbc) +{ + unsigned long flags; + struct qaic_bo *bo; + + spin_lock_irqsave(&dbc->xfer_lock, flags); + while (!list_empty(&dbc->xfer_list)) { + bo = list_first_entry(&dbc->xfer_list, typeof(*bo), xfer_list); + bo->queued = false; + list_del(&bo->xfer_list); + spin_unlock_irqrestore(&dbc->xfer_lock, flags); + dma_sync_sgtable_for_cpu(&qdev->pdev->dev, bo->sgt, bo->dir); + complete_all(&bo->xfer_done); + drm_gem_object_put(&bo->base); + spin_lock_irqsave(&dbc->xfer_lock, flags); + } + spin_unlock_irqrestore(&dbc->xfer_lock, flags); +} + +int disable_dbc(struct qaic_device *qdev, u32 dbc_id, struct qaic_user *usr) +{ + if (!qdev->dbc[dbc_id].usr || qdev->dbc[dbc_id].usr->handle != usr->handle) + return -EPERM; + + qdev->dbc[dbc_id].usr = NULL; + synchronize_srcu(&qdev->dbc[dbc_id].ch_lock); + return 0; +} + +/** + * enable_dbc - Enable the DBC. DBCs are disabled by removing the context of + * user. Add user context back to DBC to enable it. This function trusts the + * DBC ID passed and expects the DBC to be disabled. + * @qdev: Qranium device handle + * @dbc_id: ID of the DBC + * @usr: User context + */ +void enable_dbc(struct qaic_device *qdev, u32 dbc_id, struct qaic_user *usr) +{ + qdev->dbc[dbc_id].usr = usr; +} + +void wakeup_dbc(struct qaic_device *qdev, u32 dbc_id) +{ + struct dma_bridge_chan *dbc = &qdev->dbc[dbc_id]; + + dbc->usr = NULL; + empty_xfer_list(qdev, dbc); + synchronize_srcu(&dbc->ch_lock); +} + +void release_dbc(struct qaic_device *qdev, u32 dbc_id) +{ + struct bo_slice *slice, *slice_temp; + struct qaic_bo *bo, *bo_temp; + struct dma_bridge_chan *dbc; + + dbc = &qdev->dbc[dbc_id]; + if (!dbc->in_use) + return; + + wakeup_dbc(qdev, dbc_id); + + dma_free_coherent(&qdev->pdev->dev, dbc->total_size, dbc->req_q_base, dbc->dma_addr); + dbc->total_size = 0; + dbc->req_q_base = NULL; + dbc->dma_addr = 0; + dbc->nelem = 0; + dbc->usr = NULL; + + list_for_each_entry_safe(bo, bo_temp, &dbc->bo_lists, bo_list) { + list_for_each_entry_safe(slice, slice_temp, &bo->slices, slice) + kref_put(&slice->ref_count, free_slice); + bo->sliced = false; + INIT_LIST_HEAD(&bo->slices); + bo->total_slice_nents = 0; + bo->dir = 0; + bo->dbc = NULL; + bo->nr_slice = 0; + bo->nr_slice_xfer_done = 0; + bo->queued = false; + bo->req_id = 0; + init_completion(&bo->xfer_done); + complete_all(&bo->xfer_done); + list_del(&bo->bo_list); + bo->perf_stats.req_received_ts = 0; + bo->perf_stats.req_submit_ts = 0; + bo->perf_stats.req_processed_ts = 0; + bo->perf_stats.queue_level_before = 0; + } + + dbc->in_use = false; + wake_up(&dbc->dbc_release); +} -- 2.7.4