[RFC PATCH 5/8] qaic: Implement data path

From: Jeffrey Hugo
Date: Thu May 14 2020 - 10:08:53 EST

Once a user has configured the device via the control path for their
workload, the user may use the data path to execute the workload. Using
the data path involves several steps.

First, the user must use the memory ioctl to allocate one or more buffers
for use by the workload. These buffers hold input data, and results.
The memory ioctl can also be used to free buffers once no longer needed.

Next, the user must mmap() the buffers, to gain access to them.

To submit buffers to the device, the user uses the execute ioctl.

Finally, the user may use the wait for execute ioctl to determine when
the device has completed its handling of submitted buffers (ie consumed
input data, or produced output).

Signed-off-by: Jeffrey Hugo <jhugo@xxxxxxxxxxxxxx>
---
drivers/misc/qaic/Makefile | 3 +-
drivers/misc/qaic/qaic.h | 11 +
drivers/misc/qaic/qaic_data.c | 952 ++++++++++++++++++++++++++++++++++++++++++
drivers/misc/qaic/qaic_drv.c | 116 +++--
include/uapi/misc/qaic.h | 129 ++++++
5 files changed, 1175 insertions(+), 36 deletions(-)
create mode 100644 drivers/misc/qaic/qaic_data.c

diff --git a/drivers/misc/qaic/Makefile b/drivers/misc/qaic/Makefile
index 7a5513b..d17ee0a 100644
--- a/drivers/misc/qaic/Makefile
+++ b/drivers/misc/qaic/Makefile
@@ -8,4 +8,5 @@ obj-$(CONFIG_QAIC) := qaic.o
qaic-y := \
qaic_drv.o \
mhi_controller.o \
- qaic_control.o
+ qaic_control.o \
+ qaic_data.o
diff --git a/drivers/misc/qaic/qaic.h b/drivers/misc/qaic/qaic.h
index c35a4e1..5f774d4 100644
--- a/drivers/misc/qaic/qaic.h
+++ b/drivers/misc/qaic/qaic.h
@@ -8,6 +8,7 @@

#include <linux/cdev.h>
#include <linux/idr.h>
+#include <linux/interrupt.h>
#include <linux/kref.h>
#include <linux/mhi.h>
#include <linux/mutex.h>
@@ -80,6 +81,14 @@ int get_cntl_version(struct qaic_device *qdev, struct qaic_user *usr,
u16 *major, u16 *minor);
int qaic_manage_ioctl(struct qaic_device *qdev, struct qaic_user *usr,
unsigned long arg);
+int qaic_mem_ioctl(struct qaic_device *qdev, struct qaic_user *usr,
+ unsigned long arg);
+int qaic_execute_ioctl(struct qaic_device *qdev, struct qaic_user *usr,
+ unsigned long arg);
+int qaic_wait_exec_ioctl(struct qaic_device *qdev, struct qaic_user *usr,
+ unsigned long arg);
+int qaic_data_mmap(struct qaic_device *qdev, struct qaic_user *usr,
+ struct vm_area_struct *vma);

void qaic_mhi_ul_xfer_cb(struct mhi_device *mhi_dev,
struct mhi_result *mhi_result);
@@ -91,7 +100,9 @@ int qaic_control_open(struct qaic_device *qdev);
void qaic_control_close(struct qaic_device *qdev);
void qaic_release_usr(struct qaic_device *qdev, struct qaic_user *usr);

+irqreturn_t dbc_irq_handler(int irq, void *data);
int disable_dbc(struct qaic_device *qdev, u32 dbc_id, struct qaic_user *usr);
+void wakeup_dbc(struct qaic_device *qdev, u32 dbc_id);
void release_dbc(struct qaic_device *qdev, u32 dbc_id);

void wake_all_cntl(struct qaic_device *qdev);
diff --git a/drivers/misc/qaic/qaic_data.c b/drivers/misc/qaic/qaic_data.c
new file mode 100644
index 0000000..4261a3c
--- /dev/null
+++ b/drivers/misc/qaic/qaic_data.c
@@ -0,0 +1,952 @@
+// SPDX-License-Identifier: GPL-2.0-only
+
+/* Copyright (c) 2019-2020, The Linux Foundation. All rights reserved. */
+
+#include <linux/completion.h>
+#include <linux/dma-mapping.h>
+#include <linux/idr.h>
+#include <linux/kref.h>
+#include <linux/list.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 <uapi/misc/qaic.h>
+
+#include "qaic.h"
+
+#define PGOFF_DBC_SHIFT 32
+#define PGOFF_DBC_MASK GENMASK_ULL(63, 32)
+#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) \
+ ((val) | \
+ (index) << 16 | \
+ (sync) << 22 | \
+ (cmd) << 24 | \
+ ((cmd) ? BIT(31) : 0) | \
+ (((flags) & SEM_INSYNCFENCE) ? BIT(30) : 0) | \
+ (((flags) & SEM_OUTSYNCFENCE) ? BIT(29) : 0))
+
+static unsigned int wait_exec_default_timeout = 5000; /* 5 sec default */
+module_param(wait_exec_default_timeout, uint, 0600);
+
+struct dbc_req { /* everything must be little endian encoded */
+ u16 req_id;
+ u8 seq_id;
+ u8 cmd;
+ u32 resv;
+ u64 src_addr;
+ u64 dest_addr;
+ u32 len;
+ u32 resv2;
+ u64 db_addr; /* doorbell address */
+ u8 db_len; /* not a raw value, special encoding */
+ u8 resv3;
+ u16 resv4;
+ u32 db_data;
+ u32 sem_cmd0;
+ u32 sem_cmd1;
+ u32 sem_cmd2;
+ u32 sem_cmd3;
+} __packed;
+
+struct dbc_rsp { /* everything must be little endian encoded */
+ u16 req_id;
+ u16 status;
+} __packed;
+
+struct mem_handle {
+ struct sg_table *sgt; /* Mapped pages */
+ int nents; /* num dma mapped elements in sgt */
+ int dir; /* see enum dma_data_direction */
+ struct dbc_req *reqs;
+ struct list_head list;
+ u16 req_id;/* req_id for the xfer while in flight */
+ struct completion xfer_done;
+ struct kref ref_count;
+ struct qaic_device *qdev;
+ bool queued;
+ bool no_xfer;
+};
+
+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 int reserve_pages(unsigned long start_pfn, unsigned long nr_pages,
+ bool reserve)
+{
+ unsigned long pfn;
+ unsigned long end_pfn = start_pfn + nr_pages;
+ struct page *page;
+
+ for (pfn = start_pfn; pfn < end_pfn; pfn++) {
+ if (!pfn_valid(pfn))
+ return -EINVAL;
+ page = pfn_to_page(pfn);
+ if (reserve)
+ SetPageReserved(page);
+ else
+ ClearPageReserved(page);
+ }
+ return 0;
+}
+
+static int alloc_handle(struct qaic_device *qdev, struct qaic_mem_req *req)
+{
+ struct mem_handle *mem;
+ struct scatterlist *sg;
+ struct sg_table *sgt;
+ struct page *page;
+ int buf_extra;
+ int max_order;
+ int nr_pages;
+ int order;
+ int nents;
+ int ret;
+
+ if (!(req->dir == DMA_TO_DEVICE || req->dir == DMA_FROM_DEVICE ||
+ req->dir == DMA_BIDIRECTIONAL)) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ mem = kmalloc(sizeof(*mem), GFP_KERNEL);
+ if (!mem) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ if (req->size) {
+ nr_pages = DIV_ROUND_UP(req->size, PAGE_SIZE);
+ /*
+ * calculate how much extra we are going to allocate, to remove
+ * later
+ */
+ buf_extra = (PAGE_SIZE - req->size % PAGE_SIZE) % PAGE_SIZE;
+ max_order = min(MAX_ORDER, get_order(req->size));
+ mem->no_xfer = false;
+ } else {
+ /* allocate a single page for book keeping */
+ nr_pages = 1;
+ buf_extra = 0;
+ max_order = 0;
+ mem->no_xfer = true;
+ }
+
+ sgt = kmalloc(sizeof(*sgt), GFP_KERNEL);
+ if (!sgt) {
+ ret = -ENOMEM;
+ goto free_mem;
+ }
+
+ if (sg_alloc_table(sgt, nr_pages, GFP_KERNEL)) {
+ ret = -ENOMEM;
+ goto free_sgt;
+ }
+
+ sg = sgt->sgl;
+ sgt->nents = 0;
+
+ /*
+ * Try to allocate enough pages to cover the request. High order pages
+ * will be contiguous, which will be conducive to DMA.
+ */
+ while (1) {
+ order = min(fls(nr_pages) - 1, max_order);
+ while (1) {
+ page = alloc_pages(GFP_KERNEL | GFP_HIGHUSER |
+ __GFP_NOWARN | __GFP_ZERO |
+ (order ? __GFP_NORETRY :
+ __GFP_RETRY_MAYFAIL),
+ order);
+ if (page)
+ break;
+ if (!order--) {
+ sg_set_page(sg, NULL, 0, 0);
+ sg_mark_end(sg);
+ ret = -ENOMEM;
+ goto free_partial_alloc;
+ }
+ max_order = order;
+ }
+
+ if (reserve_pages(page_to_pfn(page), 1 << order, true))
+ goto free_partial_alloc;
+
+ sg_set_page(sg, page, PAGE_SIZE << order, 0);
+ sgt->nents++;
+ nr_pages -= 1 << order;
+ if (!nr_pages) {
+ if (buf_extra)
+ sg_set_page(sg, page,
+ (PAGE_SIZE << order) - buf_extra,
+ 0);
+ sg_mark_end(sg);
+ break;
+ }
+ sg = sg_next(sg);
+ }
+
+ nents = dma_map_sg(&qdev->pdev->dev, sgt->sgl, sgt->nents, req->dir);
+ if (!nents) {
+ ret = -EFAULT;
+ goto free_partial_alloc;
+ }
+
+ if (req->dir == DMA_TO_DEVICE || req->dir == DMA_BIDIRECTIONAL)
+ dma_sync_sg_for_cpu(&qdev->pdev->dev, sgt->sgl, sgt->nents,
+ req->dir);
+
+ mem->reqs = kcalloc(nents, sizeof(*mem->reqs), GFP_KERNEL);
+ if (!mem->reqs) {
+ ret = -ENOMEM;
+ goto req_alloc_fail;
+ }
+
+ mem->sgt = sgt;
+ mem->nents = nents;
+ mem->dir = req->dir;
+ mem->qdev = qdev;
+ mem->queued = false;
+
+ ret = mutex_lock_interruptible(&qdev->dbc[req->dbc_id].mem_lock);
+ if (ret)
+ goto lock_fail;
+ ret = idr_alloc(&qdev->dbc[req->dbc_id].mem_handles, mem, 1, 0,
+ GFP_KERNEL);
+ mutex_unlock(&qdev->dbc[req->dbc_id].mem_lock);
+ if (ret < 0)
+ goto lock_fail;
+
+ req->handle = ret | (u64)req->dbc_id << PGOFF_DBC_SHIFT;
+ /*
+ * When userspace uses the handle as the offset parameter to mmap,
+ * it needs to be in multiples of PAGE_SIZE.
+ */
+ req->handle <<= PAGE_SHIFT;
+
+ kref_init(&mem->ref_count);
+
+ return 0;
+
+lock_fail:
+ kfree(mem->reqs);
+req_alloc_fail:
+ dma_unmap_sg(&qdev->pdev->dev, sgt->sgl, sgt->nents, req->dir);
+free_partial_alloc:
+ for (sg = sgt->sgl; sg; sg = sg_next(sg))
+ if (sg_page(sg)) {
+ reserve_pages(page_to_pfn(sg_page(sg)),
+ DIV_ROUND_UP(sg->length, PAGE_SIZE),
+ false);
+ __free_pages(sg_page(sg), get_order(sg->length));
+ }
+ sg_free_table(sgt);
+free_sgt:
+ kfree(sgt);
+free_mem:
+ kfree(mem);
+out:
+ return ret;
+}
+
+static void free_handle_mem(struct kref *kref)
+{
+ struct mem_handle *mem = container_of(kref, struct mem_handle,
+ ref_count);
+ struct scatterlist *sg;
+ struct sg_table *sgt;
+
+ sgt = mem->sgt;
+ dma_unmap_sg(&mem->qdev->pdev->dev, sgt->sgl, sgt->nents, mem->dir);
+ for (sg = sgt->sgl; sg; sg = sg_next(sg))
+ if (sg_page(sg)) {
+ reserve_pages(page_to_pfn(sg_page(sg)),
+ DIV_ROUND_UP(sg->length, PAGE_SIZE),
+ false);
+ __free_pages(sg_page(sg), get_order(sg->length));
+ }
+ sg_free_table(sgt);
+ kfree(sgt);
+ kfree(mem->reqs);
+ kfree(mem);
+}
+
+static int free_handle(struct qaic_device *qdev, struct qaic_mem_req *req)
+{
+ struct mem_handle *mem;
+ unsigned long flags;
+ int handle;
+ int dbc_id;
+ int ret;
+
+ handle = req->handle & ~PGOFF_DBC_MASK;
+ dbc_id = (req->handle & PGOFF_DBC_MASK) >> PGOFF_DBC_SHIFT;
+
+ /* we shifted up by PAGE_SHIFT to make mmap happy, need to undo that */
+ handle >>= PAGE_SHIFT;
+ dbc_id >>= PAGE_SHIFT;
+
+ if (dbc_id != req->dbc_id)
+ return -EINVAL;
+
+ ret = mutex_lock_interruptible(&qdev->dbc[dbc_id].mem_lock);
+ if (ret)
+ goto lock_fail;
+ mem = idr_find(&qdev->dbc[dbc_id].mem_handles, handle);
+ if (mem) {
+ spin_lock_irqsave(&qdev->dbc[dbc_id].xfer_lock, flags);
+ if (mem->queued)
+ ret = -EINVAL;
+ else
+ idr_remove(&qdev->dbc[dbc_id].mem_handles, handle);
+ spin_unlock_irqrestore(&qdev->dbc[dbc_id].xfer_lock, flags);
+ } else {
+ ret = -ENODEV;
+ }
+ mutex_unlock(&qdev->dbc[dbc_id].mem_lock);
+ if (ret)
+ goto lock_fail;
+
+ kref_put(&mem->ref_count, free_handle_mem);
+
+ ret = 0;
+
+lock_fail:
+ return ret;
+}
+
+int qaic_mem_ioctl(struct qaic_device *qdev, struct qaic_user *usr,
+ unsigned long arg)
+{
+ struct qaic_mem_req req;
+ int rcu_id;
+ int ret;
+
+ if (copy_from_user(&req, (void __user *)arg, sizeof(req))) {
+ ret = -EFAULT;
+ goto out;
+ }
+
+ if (req.dbc_id >= QAIC_NUM_DBC || req.resv) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ rcu_id = srcu_read_lock(&qdev->dbc[req.dbc_id].ch_lock);
+ if (!qdev->dbc[req.dbc_id].usr ||
+ usr->handle != qdev->dbc[req.dbc_id].usr->handle) {
+ ret = -EPERM;
+ goto release_rcu;
+ }
+
+ if (!req.handle) {
+ ret = alloc_handle(qdev, &req);
+ if (!ret && copy_to_user((void __user *)arg, &req,
+ sizeof(req))) {
+ ret = -EFAULT;
+ free_handle(qdev, &req);
+ goto release_rcu;
+ }
+ } else {
+ ret = free_handle(qdev, &req);
+ }
+
+release_rcu:
+ srcu_read_unlock(&qdev->dbc[req.dbc_id].ch_lock, rcu_id);
+out:
+ return ret;
+}
+
+int qaic_data_mmap(struct qaic_device *qdev, struct qaic_user *usr,
+ struct vm_area_struct *vma)
+{
+ unsigned long offset = 0;
+ struct mem_handle *mem;
+ struct scatterlist *sg;
+ int handle;
+ int dbc_id;
+ int rcu_id;
+ int ret;
+
+ dbc_id = (vma->vm_pgoff & PGOFF_DBC_MASK) >> PGOFF_DBC_SHIFT;
+ handle = vma->vm_pgoff & ~PGOFF_DBC_MASK;
+
+ if (dbc_id >= QAIC_NUM_DBC) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ rcu_id = srcu_read_lock(&qdev->dbc[dbc_id].ch_lock);
+ if (!qdev->dbc[dbc_id].usr ||
+ usr->handle != qdev->dbc[dbc_id].usr->handle) {
+ ret = -EPERM;
+ goto release_rcu;
+ }
+
+ ret = mutex_lock_interruptible(&qdev->dbc[dbc_id].mem_lock);
+ if (ret)
+ goto release_rcu;
+ mem = idr_find(&qdev->dbc[dbc_id].mem_handles, handle);
+ mutex_unlock(&qdev->dbc[dbc_id].mem_lock);
+ if (!mem) {
+ ret = -ENODEV;
+ goto release_rcu;
+ }
+
+ if (mem->no_xfer) {
+ ret = -EINVAL;
+ goto release_rcu;
+ }
+
+ for (sg = mem->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 release_rcu;
+ offset += sg->length;
+ }
+ }
+
+release_rcu:
+ srcu_read_unlock(&qdev->dbc[dbc_id].ch_lock, rcu_id);
+out:
+ 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->resv ||
+ sem->flags & ~(SEM_INSYNCFENCE | SEM_OUTSYNCFENCE) ||
+ sem->cmd > SEM_WAIT_GT_0)
+ return true;
+ return false;
+}
+
+static int encode_execute(struct qaic_device *qdev, struct mem_handle *mem,
+ struct qaic_execute *exec, u16 req_id)
+{
+ u8 cmd = BULK_XFER;
+ u64 db_addr = cpu_to_le64(exec->db_addr);
+ u8 db_len;
+ u32 db_data = cpu_to_le32(exec->db_data);
+ struct scatterlist *sg;
+ u64 dev_addr;
+ int presync_sem;
+ int i;
+
+ if (!mem->no_xfer)
+ cmd |= (exec->dir == DMA_TO_DEVICE ? INBOUND_XFER :
+ OUTBOUND_XFER);
+
+ req_id = cpu_to_le16(req_id);
+
+ if (exec->db_len && !IS_ALIGNED(exec->db_addr, exec->db_len / 8))
+ return -EINVAL;
+
+ presync_sem = exec->sem0.presync + exec->sem1.presync +
+ exec->sem2.presync + exec->sem3.presync;
+ if (presync_sem > 1)
+ return -EINVAL;
+
+ presync_sem = exec->sem0.presync << 0 | exec->sem1.presync << 1 |
+ exec->sem2.presync << 2 | exec->sem3.presync << 3;
+
+ switch (exec->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 mem handle) 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 = exec->dev_addr;
+ for_each_sg(mem->sgt->sgl, sg, mem->nents, i) {
+ mem->reqs[i].req_id = req_id;
+ mem->reqs[i].cmd = cmd;
+ mem->reqs[i].src_addr =
+ cpu_to_le64(exec->dir == DMA_TO_DEVICE ?
+ sg_dma_address(sg) : dev_addr);
+ mem->reqs[i].dest_addr =
+ cpu_to_le64(exec->dir == DMA_TO_DEVICE ?
+ dev_addr : sg_dma_address(sg));
+ mem->reqs[i].len = cpu_to_le32(sg_dma_len(sg));
+ switch (presync_sem) {
+ case BIT(0):
+ mem->reqs[i].sem_cmd0 = cpu_to_le32(
+ ENCODE_SEM(exec->sem0.val,
+ exec->sem0.index,
+ exec->sem0.presync,
+ exec->sem0.cmd,
+ exec->sem0.flags));
+ break;
+ case BIT(1):
+ mem->reqs[i].sem_cmd1 = cpu_to_le32(
+ ENCODE_SEM(exec->sem1.val,
+ exec->sem1.index,
+ exec->sem1.presync,
+ exec->sem1.cmd,
+ exec->sem1.flags));
+ break;
+ case BIT(2):
+ mem->reqs[i].sem_cmd2 = cpu_to_le32(
+ ENCODE_SEM(exec->sem2.val,
+ exec->sem2.index,
+ exec->sem2.presync,
+ exec->sem2.cmd,
+ exec->sem2.flags));
+ break;
+ case BIT(3):
+ mem->reqs[i].sem_cmd3 = cpu_to_le32(
+ ENCODE_SEM(exec->sem3.val,
+ exec->sem3.index,
+ exec->sem3.presync,
+ exec->sem3.cmd,
+ exec->sem3.flags));
+ break;
+ }
+ dev_addr += sg_dma_len(sg);
+ }
+ /* add post transfer stuff to last segment */
+ i--;
+ mem->reqs[i].cmd |= GEN_COMPLETION;
+ mem->reqs[i].db_addr = db_addr;
+ mem->reqs[i].db_len = db_len;
+ mem->reqs[i].db_data = db_data;
+ exec->sem0.flags |= (exec->dir == DMA_TO_DEVICE ? SEM_INSYNCFENCE :
+ SEM_OUTSYNCFENCE);
+ mem->reqs[i].sem_cmd0 = cpu_to_le32(ENCODE_SEM(exec->sem0.val,
+ exec->sem0.index,
+ exec->sem0.presync,
+ exec->sem0.cmd,
+ exec->sem0.flags));
+ mem->reqs[i].sem_cmd1 = cpu_to_le32(ENCODE_SEM(exec->sem1.val,
+ exec->sem1.index,
+ exec->sem1.presync,
+ exec->sem1.cmd,
+ exec->sem1.flags));
+ mem->reqs[i].sem_cmd2 = cpu_to_le32(ENCODE_SEM(exec->sem2.val,
+ exec->sem2.index,
+ exec->sem2.presync,
+ exec->sem2.cmd,
+ exec->sem2.flags));
+ mem->reqs[i].sem_cmd3 = cpu_to_le32(ENCODE_SEM(exec->sem3.val,
+ exec->sem3.index,
+ exec->sem3.presync,
+ exec->sem3.cmd,
+ exec->sem3.flags));
+
+ return 0;
+}
+
+static int commit_execute(struct qaic_device *qdev, struct mem_handle *mem,
+ u32 dbc_id)
+{
+ struct dma_bridge_chan *dbc = &qdev->dbc[dbc_id];
+ u32 head = le32_to_cpu(__raw_readl(dbc->dbc_base + REQHP_OFF));
+ u32 tail = le32_to_cpu(__raw_readl(dbc->dbc_base + REQTP_OFF));
+ u32 avail = head - tail;
+ struct dbc_req *reqs = mem->reqs;
+ bool two_copy = tail + mem->nents > dbc->nelem;
+
+ if (head == U32_MAX || tail == U32_MAX)
+ /* PCI link error */
+ return -ENODEV;
+
+ if (head <= tail)
+ avail += dbc->nelem;
+
+ --avail;
+
+ if (avail < mem->nents)
+ return -EAGAIN;
+
+ if (two_copy) {
+ avail = dbc->nelem - tail;
+ avail = min_t(u32, avail, mem->nents);
+ memcpy(dbc->req_q_base + tail * get_dbc_req_elem_size(),
+ reqs, sizeof(*reqs) * avail);
+ reqs += avail;
+ avail = mem->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) * mem->nents);
+ }
+
+ init_completion(&mem->xfer_done);
+ list_add_tail(&mem->list, &dbc->xfer_list);
+ tail = (tail + mem->nents) % dbc->nelem;
+ __raw_writel(cpu_to_le32(tail), dbc->dbc_base + REQTP_OFF);
+ return 0;
+}
+
+int qaic_execute_ioctl(struct qaic_device *qdev, struct qaic_user *usr,
+ unsigned long arg)
+{
+ struct mem_handle *mem;
+ struct qaic_execute *exec;
+ unsigned long flags;
+ bool queued;
+ u16 req_id;
+ int handle;
+ int dbc_id;
+ int rcu_id;
+ int ret;
+
+ exec = kmalloc(sizeof(*exec), GFP_KERNEL);
+ if (!exec) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ if (copy_from_user(exec, (void __user *)arg, sizeof(*exec))) {
+ ret = -EFAULT;
+ goto free_exec;
+ }
+
+ if (exec->dbc_id > QAIC_NUM_DBC || exec->ver != 1 ||
+ !(exec->dir == 1 || exec->dir == 2) ||
+ !(exec->db_len == 32 || exec->db_len == 16 || exec->db_len == 8 ||
+ exec->db_len == 0) ||
+ invalid_sem(&exec->sem0) || invalid_sem(&exec->sem1) ||
+ invalid_sem(&exec->sem2) || invalid_sem(&exec->sem3) ||
+ exec->resv) {
+ ret = -EINVAL;
+ goto free_exec;
+ }
+
+ rcu_id = srcu_read_lock(&qdev->dbc[exec->dbc_id].ch_lock);
+ if (!qdev->dbc[exec->dbc_id].usr ||
+ qdev->dbc[exec->dbc_id].usr->handle != usr->handle) {
+ ret = -EPERM;
+ goto release_rcu;
+ }
+
+ handle = exec->handle & ~PGOFF_DBC_MASK;
+ dbc_id = (exec->handle & PGOFF_DBC_MASK) >> PGOFF_DBC_SHIFT;
+
+ /* we shifted up by PAGE_SHIFT to make mmap happy, need to undo that */
+ handle >>= PAGE_SHIFT;
+ dbc_id >>= PAGE_SHIFT;
+
+ if (dbc_id != exec->dbc_id) {
+ ret = -EINVAL;
+ goto release_rcu;
+ }
+
+ ret = mutex_lock_interruptible(&qdev->dbc[exec->dbc_id].mem_lock);
+ if (ret)
+ goto release_rcu;
+ mem = idr_find(&qdev->dbc[exec->dbc_id].mem_handles, handle);
+ if (!mem) {
+ ret = -ENODEV;
+ mutex_unlock(&qdev->dbc[exec->dbc_id].mem_lock);
+ goto release_rcu;
+ }
+ /* prevent free_handle from taking the memory from under us */
+ kref_get(&mem->ref_count);
+ mutex_unlock(&qdev->dbc[exec->dbc_id].mem_lock);
+
+ if (mem->dir != DMA_BIDIRECTIONAL && mem->dir != exec->dir) {
+ ret = -EINVAL;
+ kref_put(&mem->ref_count, free_handle_mem);
+ goto release_rcu;
+ }
+
+ spin_lock_irqsave(&qdev->dbc[exec->dbc_id].xfer_lock, flags);
+ req_id = qdev->dbc[exec->dbc_id].next_req_id++;
+ queued = mem->queued;
+ mem->queued = true;
+ spin_unlock_irqrestore(&qdev->dbc[exec->dbc_id].xfer_lock, flags);
+ mem->req_id = req_id;
+
+ if (queued) {
+ ret = -EINVAL;
+ kref_put(&mem->ref_count, free_handle_mem);
+ goto release_rcu;
+ }
+
+ ret = encode_execute(qdev, mem, exec, req_id);
+ if (ret) {
+ mem->queued = false;
+ kref_put(&mem->ref_count, free_handle_mem);
+ goto release_rcu;
+ }
+
+ dma_sync_sg_for_device(&qdev->pdev->dev, mem->sgt->sgl, mem->sgt->nents,
+ mem->dir);
+
+ spin_lock_irqsave(&qdev->dbc[exec->dbc_id].xfer_lock, flags);
+ ret = commit_execute(qdev, mem, exec->dbc_id);
+ spin_unlock_irqrestore(&qdev->dbc[exec->dbc_id].xfer_lock, flags);
+ if (ret) {
+ mem->queued = false;
+ kref_put(&mem->ref_count, free_handle_mem);
+ goto sync_to_cpu;
+ }
+
+ goto release_rcu;
+
+sync_to_cpu:
+ dma_sync_sg_for_cpu(&qdev->pdev->dev, mem->sgt->sgl, mem->sgt->nents,
+ mem->dir);
+release_rcu:
+ srcu_read_unlock(&qdev->dbc[exec->dbc_id].ch_lock, rcu_id);
+free_exec:
+ kfree(exec);
+out:
+ return ret;
+}
+
+irqreturn_t dbc_irq_handler(int irq, void *data)
+{
+ struct dma_bridge_chan *dbc = data;
+ struct qaic_device *qdev = dbc->qdev;
+ struct mem_handle *mem;
+ struct mem_handle *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);
+read_fifo:
+ /*
+ * if this channel isn't assigned or gets unassigned during processing
+ * we have nothing further to do
+ */
+ if (!dbc->usr) {
+ srcu_read_unlock(&dbc->ch_lock, rcu_id);
+ return IRQ_HANDLED;
+ }
+
+ head = le32_to_cpu(__raw_readl(dbc->dbc_base + RSPHP_OFF));
+ tail = le32_to_cpu(__raw_readl(dbc->dbc_base + RSPTP_OFF));
+
+ if (head == U32_MAX || tail == U32_MAX) {
+ /* PCI link error */
+ srcu_read_unlock(&dbc->ch_lock, rcu_id);
+ return IRQ_HANDLED;
+ }
+
+ if (head == tail) { /* queue empty */
+ srcu_read_unlock(&dbc->ch_lock, rcu_id);
+ return IRQ_HANDLED;
+ }
+
+ while (head != tail) {
+ 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);
+ list_for_each_entry_safe(mem, i, &dbc->xfer_list, list) {
+ if (mem->req_id == req_id) {
+ list_del(&mem->list);
+ dma_sync_sg_for_cpu(&qdev->pdev->dev,
+ mem->sgt->sgl,
+ mem->sgt->nents,
+ mem->dir);
+ mem->queued = false;
+ complete_all(&mem->xfer_done);
+ kref_put(&mem->ref_count, free_handle_mem);
+ break;
+ }
+ }
+ spin_unlock_irqrestore(&dbc->xfer_lock, flags);
+ head = (head + 1) % dbc->nelem;
+ __raw_writel(cpu_to_le32(head), dbc->dbc_base + RSPHP_OFF);
+ }
+
+ /* elements might have been put in the queue while we were processing */
+ goto read_fifo;
+}
+
+int qaic_wait_exec_ioctl(struct qaic_device *qdev, struct qaic_user *usr,
+ unsigned long arg)
+{
+ struct mem_handle *mem;
+ struct qaic_wait_exec *wait;
+ unsigned int timeout;
+ int handle;
+ int dbc_id;
+ int rcu_id;
+ int ret;
+
+ wait = kmalloc(sizeof(*wait), GFP_KERNEL);
+ if (!wait) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ if (copy_from_user(wait, (void __user *)arg, sizeof(*wait))) {
+ ret = -EFAULT;
+ goto free_wait;
+ }
+
+ if (wait->resv) {
+ ret = -EINVAL;
+ goto free_wait;
+ }
+
+ handle = wait->handle & ~PGOFF_DBC_MASK;
+ dbc_id = (wait->handle & PGOFF_DBC_MASK) >> PGOFF_DBC_SHIFT;
+
+ /* we shifted up by PAGE_SHIFT to make mmap happy, need to undo that */
+ handle >>= PAGE_SHIFT;
+ dbc_id >>= PAGE_SHIFT;
+
+ if (dbc_id > QAIC_NUM_DBC) {
+ ret = -EINVAL;
+ goto free_wait;
+ }
+
+ rcu_id = srcu_read_lock(&qdev->dbc[dbc_id].ch_lock);
+ if (!qdev->dbc[dbc_id].usr ||
+ qdev->dbc[dbc_id].usr->handle != usr->handle) {
+ ret = -EPERM;
+ goto release_rcu;
+ }
+
+ ret = mutex_lock_interruptible(&qdev->dbc[dbc_id].mem_lock);
+ if (ret)
+ goto release_rcu;
+ mem = idr_find(&qdev->dbc[dbc_id].mem_handles, handle);
+ mutex_unlock(&qdev->dbc[dbc_id].mem_lock);
+ if (!mem) {
+ ret = -ENODEV;
+ goto release_rcu;
+ }
+
+ /* we don't want the mem handle freed under us in case of deactivate */
+ kref_get(&mem->ref_count);
+ srcu_read_unlock(&qdev->dbc[dbc_id].ch_lock, rcu_id);
+ timeout = wait->timeout ? wait->timeout : wait_exec_default_timeout;
+ ret = wait_for_completion_interruptible_timeout(&mem->xfer_done,
+ msecs_to_jiffies(timeout));
+ rcu_id = srcu_read_lock(&qdev->dbc[dbc_id].ch_lock);
+ if (!ret)
+ ret = -ETIMEDOUT;
+ else if (ret > 0)
+ ret = 0;
+ if (!qdev->dbc[dbc_id].usr) {
+ ret = -EPERM;
+ goto release_rcu;
+ }
+
+ kref_put(&mem->ref_count, free_handle_mem);
+
+release_rcu:
+ srcu_read_unlock(&qdev->dbc[dbc_id].ch_lock, rcu_id);
+free_wait:
+ kfree(wait);
+out:
+ return ret;
+}
+
+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;
+}
+
+void wakeup_dbc(struct qaic_device *qdev, u32 dbc_id)
+{
+ struct mem_handle *mem;
+ struct mem_handle *i;
+
+ qdev->dbc[dbc_id].usr = NULL;
+ synchronize_srcu(&qdev->dbc[dbc_id].ch_lock);
+ list_for_each_entry_safe(mem, i, &qdev->dbc[dbc_id].xfer_list, list) {
+ list_del(&mem->list);
+ dma_sync_sg_for_cpu(&qdev->pdev->dev,
+ mem->sgt->sgl,
+ mem->sgt->nents,
+ mem->dir);
+ complete_all(&mem->xfer_done);
+ }
+}
+
+void release_dbc(struct qaic_device *qdev, u32 dbc_id)
+{
+ struct mem_handle *mem;
+ int next_id = 0;
+
+ wakeup_dbc(qdev, dbc_id);
+
+ dma_free_coherent(&qdev->pdev->dev, qdev->dbc[dbc_id].total_size,
+ qdev->dbc[dbc_id].req_q_base,
+ qdev->dbc[dbc_id].dma_addr);
+ qdev->dbc[dbc_id].total_size = 0;
+ qdev->dbc[dbc_id].req_q_base = NULL;
+ qdev->dbc[dbc_id].dma_addr = 0;
+ qdev->dbc[dbc_id].nelem = 0;
+ qdev->dbc[dbc_id].usr = NULL;
+ while (1) {
+ mem = idr_get_next(&qdev->dbc[dbc_id].mem_handles, &next_id);
+ if (!mem)
+ break;
+ idr_remove(&qdev->dbc[dbc_id].mem_handles, next_id);
+ /* account for the missing put from the irq handler */
+ if (mem->queued) {
+ mem->queued = false;
+ kref_put(&mem->ref_count, free_handle_mem);
+ }
+ kref_put(&mem->ref_count, free_handle_mem);
+ }
+ qdev->dbc[dbc_id].in_use = false;
+ wake_up(&qdev->dbc[dbc_id].dbc_release);
+}
diff --git a/drivers/misc/qaic/qaic_drv.c b/drivers/misc/qaic/qaic_drv.c
index 6feecc0..800769d 100644
--- a/drivers/misc/qaic/qaic_drv.c
+++ b/drivers/misc/qaic/qaic_drv.c
@@ -37,6 +37,7 @@ static bool link_up;
static int qaic_device_open(struct inode *inode, struct file *filp);
static int qaic_device_release(struct inode *inode, struct file *filp);
static long qaic_ioctl(struct file *filp, unsigned int cmd, unsigned long arg);
+static int qaic_mmap(struct file *filp, struct vm_area_struct *vma);

static const struct file_operations qaic_ops = {
.owner = THIS_MODULE,
@@ -44,6 +45,7 @@ static const struct file_operations qaic_ops = {
.release = qaic_device_release,
.unlocked_ioctl = qaic_ioctl,
.compat_ioctl = qaic_ioctl,
+ .mmap = qaic_mmap,
};

static void free_usr(struct kref *kref)
@@ -109,6 +111,7 @@ static int qaic_device_release(struct inode *inode, struct file *filp)
struct qaic_device *qdev = usr->qdev;
int qdev_rcu_id;
int usr_rcu_id;
+ int i;

usr_rcu_id = srcu_read_lock(&usr->qdev_lock);
if (qdev) {
@@ -117,6 +120,10 @@ static int qaic_device_release(struct inode *inode, struct file *filp)
pci_dbg(qdev->pdev, "%s pid:%d\n", __func__,
current->pid);
qaic_release_usr(qdev, usr);
+ for (i = 0; i < QAIC_NUM_DBC; ++i)
+ if (qdev->dbc[i].usr &&
+ qdev->dbc[i].usr->handle == usr->handle)
+ release_dbc(qdev, i);
}
srcu_read_unlock(&qdev->dev_lock, qdev_rcu_id);

@@ -171,6 +178,30 @@ static long qaic_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
}
ret = qaic_manage_ioctl(qdev, usr, arg);
break;
+ case QAIC_IOCTL_MEM_NR:
+ if (_IOC_DIR(cmd) != (_IOC_READ | _IOC_WRITE) ||
+ _IOC_SIZE(cmd) != sizeof(struct qaic_mem_req)) {
+ ret = -EINVAL;
+ break;
+ }
+ ret = qaic_mem_ioctl(qdev, usr, arg);
+ break;
+ case QAIC_IOCTL_EXECUTE_NR:
+ if (_IOC_DIR(cmd) != _IOC_WRITE ||
+ _IOC_SIZE(cmd) != sizeof(struct qaic_execute)) {
+ ret = -EINVAL;
+ break;
+ }
+ ret = qaic_execute_ioctl(qdev, usr, arg);
+ break;
+ case QAIC_IOCTL_WAIT_EXEC_NR:
+ if (_IOC_DIR(cmd) != _IOC_WRITE ||
+ _IOC_SIZE(cmd) != sizeof(struct qaic_wait_exec)) {
+ ret = -EINVAL;
+ break;
+ }
+ ret = qaic_wait_exec_ioctl(qdev, usr, arg);
+ break;
default:
ret = -ENOTTY;
}
@@ -180,6 +211,34 @@ static long qaic_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
return ret;
}

+static int qaic_mmap(struct file *filp, struct vm_area_struct *vma)
+{
+ struct qaic_user *usr = filp->private_data;
+ struct qaic_device *qdev = usr->qdev;
+ int qdev_rcu_id;
+ int usr_rcu_id;
+ int ret;
+
+ usr_rcu_id = srcu_read_lock(&usr->qdev_lock);
+ if (!qdev) {
+ srcu_read_unlock(&usr->qdev_lock, usr_rcu_id);
+ return -ENODEV;
+ }
+
+ qdev_rcu_id = srcu_read_lock(&qdev->dev_lock);
+ if (qdev->in_reset) {
+ srcu_read_unlock(&qdev->dev_lock, qdev_rcu_id);
+ srcu_read_unlock(&usr->qdev_lock, usr_rcu_id);
+ return -ENODEV;
+ }
+
+ ret = qaic_data_mmap(qdev, usr, vma);
+
+ srcu_read_unlock(&qdev->dev_lock, qdev_rcu_id);
+ srcu_read_unlock(&usr->qdev_lock, usr_rcu_id);
+ return ret;
+}
+
static int qaic_mhi_probe(struct mhi_device *mhi_dev,
const struct mhi_device_id *id)
{
@@ -284,10 +343,13 @@ void qaic_dev_reset_clean_local_state(struct qaic_device *qdev)
struct qaic_user *usr;
struct qaic_user *u;
dev_t devno;
+ int i;

qdev->in_reset = true;
/* wake up any waiters to avoid waiting for timeouts at sync */
wake_all_cntl(qdev);
+ for (i = 0; i < QAIC_NUM_DBC; ++i)
+ wakeup_dbc(qdev, i);
synchronize_srcu(&qdev->dev_lock);

/*
@@ -318,41 +380,10 @@ void qaic_dev_reset_clean_local_state(struct qaic_device *qdev)
synchronize_srcu(&usr->qdev_lock);
kref_put(&usr->ref_count, free_usr);
}
-}
-
-inline int get_dbc_req_elem_size(void)
-{
- return 64;
-}

-inline int get_dbc_rsp_elem_size(void)
-{
- return 4;
-}
-
-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;
-}
-
-void release_dbc(struct qaic_device *qdev, u32 dbc_id)
-{
- dma_free_coherent(&qdev->pdev->dev, qdev->dbc[dbc_id].total_size,
- qdev->dbc[dbc_id].req_q_base,
- qdev->dbc[dbc_id].dma_addr);
- qdev->dbc[dbc_id].total_size = 0;
- qdev->dbc[dbc_id].req_q_base = NULL;
- qdev->dbc[dbc_id].dma_addr = 0;
- qdev->dbc[dbc_id].nelem = 0;
- qdev->dbc[dbc_id].usr = NULL;
- qdev->dbc[dbc_id].in_use = false;
- wake_up(&qdev->dbc[dbc_id].dbc_release);
+ /* start tearing things down */
+ for (i = 0; i < QAIC_NUM_DBC; ++i)
+ release_dbc(qdev, i);
}

static int qaic_pci_probe(struct pci_dev *pdev,
@@ -451,6 +482,14 @@ static int qaic_pci_probe(struct pci_dev *pdev,
goto get_mhi_irq_fail;
}

+ for (i = 0; i < QAIC_NUM_DBC; ++i) {
+ ret = devm_request_irq(&pdev->dev, pci_irq_vector(pdev, i + 1),
+ dbc_irq_handler, IRQF_SHARED, "qaic_dbc",
+ &qdev->dbc[i]);
+ if (ret)
+ goto get_dbc_irq_failed;
+ }
+
qdev->mhi_cntl = qaic_mhi_register_controller(pdev, qdev->bar_0,
mhi_irq);
if (IS_ERR(qdev->mhi_cntl)) {
@@ -462,6 +501,10 @@ static int qaic_pci_probe(struct pci_dev *pdev,
return 0;

mhi_register_fail:
+get_dbc_irq_failed:
+ for (i = 0; i < QAIC_NUM_DBC; ++i)
+ devm_free_irq(&pdev->dev, pci_irq_vector(pdev, i + 1),
+ &qdev->dbc[i]);
get_mhi_irq_fail:
invalid_msi_config:
pci_free_irq_vectors(pdev);
@@ -499,8 +542,11 @@ static void qaic_pci_remove(struct pci_dev *pdev)

qaic_dev_reset_clean_local_state(qdev);
qaic_mhi_free_controller(qdev->mhi_cntl, link_up);
- for (i = 0; i < QAIC_NUM_DBC; ++i)
+ for (i = 0; i < QAIC_NUM_DBC; ++i) {
+ devm_free_irq(&pdev->dev, pci_irq_vector(pdev, i + 1),
+ &qdev->dbc[i]);
cleanup_srcu_struct(&qdev->dbc[i].ch_lock);
+ }
destroy_workqueue(qdev->cntl_wq);
pci_free_irq_vectors(pdev);
iounmap(qdev->bar_0);
diff --git a/include/uapi/misc/qaic.h b/include/uapi/misc/qaic.h
index 9bcc33f..9e7f816 100644
--- a/include/uapi/misc/qaic.h
+++ b/include/uapi/misc/qaic.h
@@ -11,6 +11,21 @@

#define QAIC_MANAGE_MAX_MSG_LENGTH 16364

+enum qaic_sem_flags {
+ SEM_INSYNCFENCE = 0x1,
+ SEM_OUTSYNCFENCE = 0x2,
+};
+
+enum qaic_sem_cmd {
+ SEM_NOP = 0,
+ SEM_INIT = 1,
+ SEM_INC = 2,
+ SEM_DEC = 3,
+ SEM_WAIT_EQUAL = 4,
+ SEM_WAIT_GT_EQ = 5, /* Greater than or equal */
+ SEM_WAIT_GT_0 = 6, /* Greater than 0 */
+};
+
enum qaic_manage_transaction_type {
TRANS_UNDEFINED = 0,
TRANS_PASSTHROUGH_FROM_USR = 1,
@@ -87,7 +102,51 @@ struct qaic_manage_msg {
__u8 data[QAIC_MANAGE_MAX_MSG_LENGTH];
};

+struct qaic_mem_req {
+ __u64 handle; /* 0 to alloc, or a valid handle to free */
+ __u64 size; /* size to alloc, will be rounded to PAGE_SIZE */
+ __u32 dir; /* direction of data: 0 = bidirectional data,
+ 1 = to device, 2 = from device */
+ __u32 dbc_id; /* Identifier of assigned DMA Bridge channel */
+ __u64 resv; /* reserved for future use, must be 0 */
+};
+
+struct qaic_sem { /* semaphore command */
+ __u16 val; /* only lower 12 bits are valid */
+ __u8 index; /* only lower 5 bits are valid */
+ __u8 presync; /* 1 if presync operation, 0 if postsync */
+ __u8 cmd; /* see enum sem_cmd */
+ __u8 flags; /* see sem_flags for valid bits. All others must be 0 */
+ __u16 resv; /* reserved for future use, must be 0 */
+};
+
+struct qaic_execute {
+ __u16 ver; /* struct version, must be 1 */
+ __u8 dir; /* 1 = to device, 2 = from device */
+ __u8 db_len; /* doorbell length - 32, 16, or 8 bits. 0 means
+ doorbell is inactive */
+ __u32 db_data;/* data to write to doorbell */
+ __u64 db_addr;/* doorbell address */
+ __u64 handle; /* mem handle from mem_req */
+ __u64 dev_addr;
+ __u32 dbc_id; /* Identifier of assigned DMA Bridge channel */
+ __u32 resv; /* reserved for future use, must be 0 */
+ struct qaic_sem sem0; /* Must be zero if not valid */
+ struct qaic_sem sem1; /* Must be zero if not valid */
+ struct qaic_sem sem2; /* Must be zero if not valid */
+ struct qaic_sem sem3; /* Must be zero if not valid */
+};
+
+struct qaic_wait_exec {
+ __u64 handle; /* handle to wait on until execute is complete */
+ __u32 timeout;/* timeout for wait (in ms). 0 means use default */
+ __u32 resv; /* reserved for future use, must be 0 */
+};
+
#define QAIC_IOCTL_MANAGE_NR 0x01
+#define QAIC_IOCTL_MEM_NR 0x02
+#define QAIC_IOCTL_EXECUTE_NR 0x03
+#define QAIC_IOCTL_WAIT_EXEC_NR 0x04

/*
* Send Manage command to the device
@@ -114,4 +173,74 @@ struct qaic_manage_msg {
*/
#define QAIC_IOCTL_MANAGE _IOWR('Q', QAIC_IOCTL_MANAGE_NR, struct manage_msg)

+/*
+ * Memory alloc/free
+ *
+ * Allows user to request buffers to send/receive data to/from the device
+ * via a DMA Bridge channel. An allocated buffer may then be mmap'd to be
+ * accessed. Buffers are tied to a specific dbc. It is expected that the
+ * user will request a pool of buffers, and reuse the buffers as necessary
+ * to send/receive multiple sets of data with the device over time.
+ *
+ * The handle to the allocated buffer will be returned in the struct upon
+ * success. A buffer to be freed cannot be accessed after the ioctl is called.
+ *
+ * A request for a 0 size buffer is valid. This signals that the DMA
+ * operation to/from the device does not transfer data, but does perform
+ * other tasks (ring doorbell, etc). A handle from a zero size request cannot
+ * be mmap()'d.
+ *
+ * The return value is 0 for success, or a standard error code. Some of the
+ * possible errors:
+ *
+ * EINTR - Kernel waiting was interrupted (IE received a signal for user)
+ * ENOMEM - Unable to obtain memory while processing request
+ * EPERM - Invalid permissions to access resource
+ * EINVAL - Invalid request
+ * EFAULT - Error in accessing memory from user
+ * ENODEV - Resource does not exist
+ */
+#define QAIC_IOCTL_MEM _IOWR('Q', QAIC_IOCTL_MEM_NR, struct mem_req)
+
+/*
+ * Execute DMA Bridge transaction
+ *
+ * Allows user to execute a DMA Bridge transaction using a previously allocated
+ * memory resource. This operation is non-blocking - success return only
+ * indicates the transaction is queued with the hardware, not that it is
+ * complete. The user must ensure that the transaction is complete before
+ * reusing the memory resource. It is invalid to attempt to execute multiple
+ * transactions concurrently which use the same memory resource in the same
+ * direction.
+ *
+ * The return value is 0 for success, or a standard error code. Some of the
+ * possible errors:
+ *
+ * ENOMEM - Unable to obtain memory while processing request
+ * EPERM - Invalid permissions to access resource
+ * EINVAL - Invalid request
+ * EFAULT - Error in accessing memory from user
+ * ENODEV - Resource does not exist
+ */
+#define QAIC_IOCTL_EXECUTE _IOW('Q', QAIC_IOCTL_EXECUTE_NR, struct execute)
+
+/*
+ * Wait for executed DMA Bridge transaction
+ *
+ * Allows user to wait for a previously executed DMA Bridge transaction.
+ * This operation is blocking.
+ *
+ * The return value is 0 for success, or a standard error code. Some of the
+ * possible errors:
+ *
+ * ENOMEM - Unable to obtain memory while processing request
+ * EPERM - Invalid permissions to access resource
+ * EINVAL - Invalid request
+ * EFAULT - Error in accessing memory from user
+ * ENODEV - Resource does not exist
+ * ETIMEDOUT - The transaction did not complete before the timeout expired
+ */
+#define QAIC_IOCTL_WAIT_EXEC _IOW('Q', QAIC_IOCTL_WAIT_EXEC_NR, \
+ struct wait_exec)
+
#endif /* QAIC_H_ */
--
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