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-rw-r--r--drivers/pci/doe.c724
1 files changed, 724 insertions, 0 deletions
diff --git a/drivers/pci/doe.c b/drivers/pci/doe.c
new file mode 100644
index 0000000000..e3aab5edaf
--- /dev/null
+++ b/drivers/pci/doe.c
@@ -0,0 +1,724 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Data Object Exchange
+ * PCIe r6.0, sec 6.30 DOE
+ *
+ * Copyright (C) 2021 Huawei
+ * Jonathan Cameron <Jonathan.Cameron@huawei.com>
+ *
+ * Copyright (C) 2022 Intel Corporation
+ * Ira Weiny <ira.weiny@intel.com>
+ */
+
+#define dev_fmt(fmt) "DOE: " fmt
+
+#include <linux/bitfield.h>
+#include <linux/delay.h>
+#include <linux/jiffies.h>
+#include <linux/mutex.h>
+#include <linux/pci.h>
+#include <linux/pci-doe.h>
+#include <linux/workqueue.h>
+
+#include "pci.h"
+
+#define PCI_DOE_PROTOCOL_DISCOVERY 0
+
+/* Timeout of 1 second from 6.30.2 Operation, PCI Spec r6.0 */
+#define PCI_DOE_TIMEOUT HZ
+#define PCI_DOE_POLL_INTERVAL (PCI_DOE_TIMEOUT / 128)
+
+#define PCI_DOE_FLAG_CANCEL 0
+#define PCI_DOE_FLAG_DEAD 1
+
+/* Max data object length is 2^18 dwords */
+#define PCI_DOE_MAX_LENGTH (1 << 18)
+
+/**
+ * struct pci_doe_mb - State for a single DOE mailbox
+ *
+ * This state is used to manage a single DOE mailbox capability. All fields
+ * should be considered opaque to the consumers and the structure passed into
+ * the helpers below after being created by pci_doe_create_mb().
+ *
+ * @pdev: PCI device this mailbox belongs to
+ * @cap_offset: Capability offset
+ * @prots: Array of protocols supported (encoded as long values)
+ * @wq: Wait queue for work item
+ * @work_queue: Queue of pci_doe_work items
+ * @flags: Bit array of PCI_DOE_FLAG_* flags
+ */
+struct pci_doe_mb {
+ struct pci_dev *pdev;
+ u16 cap_offset;
+ struct xarray prots;
+
+ wait_queue_head_t wq;
+ struct workqueue_struct *work_queue;
+ unsigned long flags;
+};
+
+struct pci_doe_protocol {
+ u16 vid;
+ u8 type;
+};
+
+/**
+ * struct pci_doe_task - represents a single query/response
+ *
+ * @prot: DOE Protocol
+ * @request_pl: The request payload
+ * @request_pl_sz: Size of the request payload (bytes)
+ * @response_pl: The response payload
+ * @response_pl_sz: Size of the response payload (bytes)
+ * @rv: Return value. Length of received response or error (bytes)
+ * @complete: Called when task is complete
+ * @private: Private data for the consumer
+ * @work: Used internally by the mailbox
+ * @doe_mb: Used internally by the mailbox
+ */
+struct pci_doe_task {
+ struct pci_doe_protocol prot;
+ const __le32 *request_pl;
+ size_t request_pl_sz;
+ __le32 *response_pl;
+ size_t response_pl_sz;
+ int rv;
+ void (*complete)(struct pci_doe_task *task);
+ void *private;
+
+ /* initialized by pci_doe_submit_task() */
+ struct work_struct work;
+ struct pci_doe_mb *doe_mb;
+};
+
+static int pci_doe_wait(struct pci_doe_mb *doe_mb, unsigned long timeout)
+{
+ if (wait_event_timeout(doe_mb->wq,
+ test_bit(PCI_DOE_FLAG_CANCEL, &doe_mb->flags),
+ timeout))
+ return -EIO;
+ return 0;
+}
+
+static void pci_doe_write_ctrl(struct pci_doe_mb *doe_mb, u32 val)
+{
+ struct pci_dev *pdev = doe_mb->pdev;
+ int offset = doe_mb->cap_offset;
+
+ pci_write_config_dword(pdev, offset + PCI_DOE_CTRL, val);
+}
+
+static int pci_doe_abort(struct pci_doe_mb *doe_mb)
+{
+ struct pci_dev *pdev = doe_mb->pdev;
+ int offset = doe_mb->cap_offset;
+ unsigned long timeout_jiffies;
+
+ pci_dbg(pdev, "[%x] Issuing Abort\n", offset);
+
+ timeout_jiffies = jiffies + PCI_DOE_TIMEOUT;
+ pci_doe_write_ctrl(doe_mb, PCI_DOE_CTRL_ABORT);
+
+ do {
+ int rc;
+ u32 val;
+
+ rc = pci_doe_wait(doe_mb, PCI_DOE_POLL_INTERVAL);
+ if (rc)
+ return rc;
+ pci_read_config_dword(pdev, offset + PCI_DOE_STATUS, &val);
+
+ /* Abort success! */
+ if (!FIELD_GET(PCI_DOE_STATUS_ERROR, val) &&
+ !FIELD_GET(PCI_DOE_STATUS_BUSY, val))
+ return 0;
+
+ } while (!time_after(jiffies, timeout_jiffies));
+
+ /* Abort has timed out and the MB is dead */
+ pci_err(pdev, "[%x] ABORT timed out\n", offset);
+ return -EIO;
+}
+
+static int pci_doe_send_req(struct pci_doe_mb *doe_mb,
+ struct pci_doe_task *task)
+{
+ struct pci_dev *pdev = doe_mb->pdev;
+ int offset = doe_mb->cap_offset;
+ size_t length, remainder;
+ u32 val;
+ int i;
+
+ /*
+ * Check the DOE busy bit is not set. If it is set, this could indicate
+ * someone other than Linux (e.g. firmware) is using the mailbox. Note
+ * it is expected that firmware and OS will negotiate access rights via
+ * an, as yet to be defined, method.
+ */
+ pci_read_config_dword(pdev, offset + PCI_DOE_STATUS, &val);
+ if (FIELD_GET(PCI_DOE_STATUS_BUSY, val))
+ return -EBUSY;
+
+ if (FIELD_GET(PCI_DOE_STATUS_ERROR, val))
+ return -EIO;
+
+ /* Length is 2 DW of header + length of payload in DW */
+ length = 2 + DIV_ROUND_UP(task->request_pl_sz, sizeof(__le32));
+ if (length > PCI_DOE_MAX_LENGTH)
+ return -EIO;
+ if (length == PCI_DOE_MAX_LENGTH)
+ length = 0;
+
+ /* Write DOE Header */
+ val = FIELD_PREP(PCI_DOE_DATA_OBJECT_HEADER_1_VID, task->prot.vid) |
+ FIELD_PREP(PCI_DOE_DATA_OBJECT_HEADER_1_TYPE, task->prot.type);
+ pci_write_config_dword(pdev, offset + PCI_DOE_WRITE, val);
+ pci_write_config_dword(pdev, offset + PCI_DOE_WRITE,
+ FIELD_PREP(PCI_DOE_DATA_OBJECT_HEADER_2_LENGTH,
+ length));
+
+ /* Write payload */
+ for (i = 0; i < task->request_pl_sz / sizeof(__le32); i++)
+ pci_write_config_dword(pdev, offset + PCI_DOE_WRITE,
+ le32_to_cpu(task->request_pl[i]));
+
+ /* Write last payload dword */
+ remainder = task->request_pl_sz % sizeof(__le32);
+ if (remainder) {
+ val = 0;
+ memcpy(&val, &task->request_pl[i], remainder);
+ le32_to_cpus(&val);
+ pci_write_config_dword(pdev, offset + PCI_DOE_WRITE, val);
+ }
+
+ pci_doe_write_ctrl(doe_mb, PCI_DOE_CTRL_GO);
+
+ return 0;
+}
+
+static bool pci_doe_data_obj_ready(struct pci_doe_mb *doe_mb)
+{
+ struct pci_dev *pdev = doe_mb->pdev;
+ int offset = doe_mb->cap_offset;
+ u32 val;
+
+ pci_read_config_dword(pdev, offset + PCI_DOE_STATUS, &val);
+ if (FIELD_GET(PCI_DOE_STATUS_DATA_OBJECT_READY, val))
+ return true;
+ return false;
+}
+
+static int pci_doe_recv_resp(struct pci_doe_mb *doe_mb, struct pci_doe_task *task)
+{
+ size_t length, payload_length, remainder, received;
+ struct pci_dev *pdev = doe_mb->pdev;
+ int offset = doe_mb->cap_offset;
+ int i = 0;
+ u32 val;
+
+ /* Read the first dword to get the protocol */
+ pci_read_config_dword(pdev, offset + PCI_DOE_READ, &val);
+ if ((FIELD_GET(PCI_DOE_DATA_OBJECT_HEADER_1_VID, val) != task->prot.vid) ||
+ (FIELD_GET(PCI_DOE_DATA_OBJECT_HEADER_1_TYPE, val) != task->prot.type)) {
+ dev_err_ratelimited(&pdev->dev, "[%x] expected [VID, Protocol] = [%04x, %02x], got [%04x, %02x]\n",
+ doe_mb->cap_offset, task->prot.vid, task->prot.type,
+ FIELD_GET(PCI_DOE_DATA_OBJECT_HEADER_1_VID, val),
+ FIELD_GET(PCI_DOE_DATA_OBJECT_HEADER_1_TYPE, val));
+ return -EIO;
+ }
+
+ pci_write_config_dword(pdev, offset + PCI_DOE_READ, 0);
+ /* Read the second dword to get the length */
+ pci_read_config_dword(pdev, offset + PCI_DOE_READ, &val);
+ pci_write_config_dword(pdev, offset + PCI_DOE_READ, 0);
+
+ length = FIELD_GET(PCI_DOE_DATA_OBJECT_HEADER_2_LENGTH, val);
+ /* A value of 0x0 indicates max data object length */
+ if (!length)
+ length = PCI_DOE_MAX_LENGTH;
+ if (length < 2)
+ return -EIO;
+
+ /* First 2 dwords have already been read */
+ length -= 2;
+ received = task->response_pl_sz;
+ payload_length = DIV_ROUND_UP(task->response_pl_sz, sizeof(__le32));
+ remainder = task->response_pl_sz % sizeof(__le32);
+
+ /* remainder signifies number of data bytes in last payload dword */
+ if (!remainder)
+ remainder = sizeof(__le32);
+
+ if (length < payload_length) {
+ received = length * sizeof(__le32);
+ payload_length = length;
+ remainder = sizeof(__le32);
+ }
+
+ if (payload_length) {
+ /* Read all payload dwords except the last */
+ for (; i < payload_length - 1; i++) {
+ pci_read_config_dword(pdev, offset + PCI_DOE_READ,
+ &val);
+ task->response_pl[i] = cpu_to_le32(val);
+ pci_write_config_dword(pdev, offset + PCI_DOE_READ, 0);
+ }
+
+ /* Read last payload dword */
+ pci_read_config_dword(pdev, offset + PCI_DOE_READ, &val);
+ cpu_to_le32s(&val);
+ memcpy(&task->response_pl[i], &val, remainder);
+ /* Prior to the last ack, ensure Data Object Ready */
+ if (!pci_doe_data_obj_ready(doe_mb))
+ return -EIO;
+ pci_write_config_dword(pdev, offset + PCI_DOE_READ, 0);
+ i++;
+ }
+
+ /* Flush excess length */
+ for (; i < length; i++) {
+ pci_read_config_dword(pdev, offset + PCI_DOE_READ, &val);
+ pci_write_config_dword(pdev, offset + PCI_DOE_READ, 0);
+ }
+
+ /* Final error check to pick up on any since Data Object Ready */
+ pci_read_config_dword(pdev, offset + PCI_DOE_STATUS, &val);
+ if (FIELD_GET(PCI_DOE_STATUS_ERROR, val))
+ return -EIO;
+
+ return received;
+}
+
+static void signal_task_complete(struct pci_doe_task *task, int rv)
+{
+ task->rv = rv;
+ destroy_work_on_stack(&task->work);
+ task->complete(task);
+}
+
+static void signal_task_abort(struct pci_doe_task *task, int rv)
+{
+ struct pci_doe_mb *doe_mb = task->doe_mb;
+ struct pci_dev *pdev = doe_mb->pdev;
+
+ if (pci_doe_abort(doe_mb)) {
+ /*
+ * If the device can't process an abort; set the mailbox dead
+ * - no more submissions
+ */
+ pci_err(pdev, "[%x] Abort failed marking mailbox dead\n",
+ doe_mb->cap_offset);
+ set_bit(PCI_DOE_FLAG_DEAD, &doe_mb->flags);
+ }
+ signal_task_complete(task, rv);
+}
+
+static void doe_statemachine_work(struct work_struct *work)
+{
+ struct pci_doe_task *task = container_of(work, struct pci_doe_task,
+ work);
+ struct pci_doe_mb *doe_mb = task->doe_mb;
+ struct pci_dev *pdev = doe_mb->pdev;
+ int offset = doe_mb->cap_offset;
+ unsigned long timeout_jiffies;
+ u32 val;
+ int rc;
+
+ if (test_bit(PCI_DOE_FLAG_DEAD, &doe_mb->flags)) {
+ signal_task_complete(task, -EIO);
+ return;
+ }
+
+ /* Send request */
+ rc = pci_doe_send_req(doe_mb, task);
+ if (rc) {
+ /*
+ * The specification does not provide any guidance on how to
+ * resolve conflicting requests from other entities.
+ * Furthermore, it is likely that busy will not be detected
+ * most of the time. Flag any detection of status busy with an
+ * error.
+ */
+ if (rc == -EBUSY)
+ dev_err_ratelimited(&pdev->dev, "[%x] busy detected; another entity is sending conflicting requests\n",
+ offset);
+ signal_task_abort(task, rc);
+ return;
+ }
+
+ timeout_jiffies = jiffies + PCI_DOE_TIMEOUT;
+ /* Poll for response */
+retry_resp:
+ pci_read_config_dword(pdev, offset + PCI_DOE_STATUS, &val);
+ if (FIELD_GET(PCI_DOE_STATUS_ERROR, val)) {
+ signal_task_abort(task, -EIO);
+ return;
+ }
+
+ if (!FIELD_GET(PCI_DOE_STATUS_DATA_OBJECT_READY, val)) {
+ if (time_after(jiffies, timeout_jiffies)) {
+ signal_task_abort(task, -EIO);
+ return;
+ }
+ rc = pci_doe_wait(doe_mb, PCI_DOE_POLL_INTERVAL);
+ if (rc) {
+ signal_task_abort(task, rc);
+ return;
+ }
+ goto retry_resp;
+ }
+
+ rc = pci_doe_recv_resp(doe_mb, task);
+ if (rc < 0) {
+ signal_task_abort(task, rc);
+ return;
+ }
+
+ signal_task_complete(task, rc);
+}
+
+static void pci_doe_task_complete(struct pci_doe_task *task)
+{
+ complete(task->private);
+}
+
+static int pci_doe_discovery(struct pci_doe_mb *doe_mb, u8 *index, u16 *vid,
+ u8 *protocol)
+{
+ u32 request_pl = FIELD_PREP(PCI_DOE_DATA_OBJECT_DISC_REQ_3_INDEX,
+ *index);
+ __le32 request_pl_le = cpu_to_le32(request_pl);
+ __le32 response_pl_le;
+ u32 response_pl;
+ int rc;
+
+ rc = pci_doe(doe_mb, PCI_VENDOR_ID_PCI_SIG, PCI_DOE_PROTOCOL_DISCOVERY,
+ &request_pl_le, sizeof(request_pl_le),
+ &response_pl_le, sizeof(response_pl_le));
+ if (rc < 0)
+ return rc;
+
+ if (rc != sizeof(response_pl_le))
+ return -EIO;
+
+ response_pl = le32_to_cpu(response_pl_le);
+ *vid = FIELD_GET(PCI_DOE_DATA_OBJECT_DISC_RSP_3_VID, response_pl);
+ *protocol = FIELD_GET(PCI_DOE_DATA_OBJECT_DISC_RSP_3_PROTOCOL,
+ response_pl);
+ *index = FIELD_GET(PCI_DOE_DATA_OBJECT_DISC_RSP_3_NEXT_INDEX,
+ response_pl);
+
+ return 0;
+}
+
+static void *pci_doe_xa_prot_entry(u16 vid, u8 prot)
+{
+ return xa_mk_value((vid << 8) | prot);
+}
+
+static int pci_doe_cache_protocols(struct pci_doe_mb *doe_mb)
+{
+ u8 index = 0;
+ u8 xa_idx = 0;
+
+ do {
+ int rc;
+ u16 vid;
+ u8 prot;
+
+ rc = pci_doe_discovery(doe_mb, &index, &vid, &prot);
+ if (rc)
+ return rc;
+
+ pci_dbg(doe_mb->pdev,
+ "[%x] Found protocol %d vid: %x prot: %x\n",
+ doe_mb->cap_offset, xa_idx, vid, prot);
+
+ rc = xa_insert(&doe_mb->prots, xa_idx++,
+ pci_doe_xa_prot_entry(vid, prot), GFP_KERNEL);
+ if (rc)
+ return rc;
+ } while (index);
+
+ return 0;
+}
+
+static void pci_doe_cancel_tasks(struct pci_doe_mb *doe_mb)
+{
+ /* Stop all pending work items from starting */
+ set_bit(PCI_DOE_FLAG_DEAD, &doe_mb->flags);
+
+ /* Cancel an in progress work item, if necessary */
+ set_bit(PCI_DOE_FLAG_CANCEL, &doe_mb->flags);
+ wake_up(&doe_mb->wq);
+}
+
+/**
+ * pci_doe_create_mb() - Create a DOE mailbox object
+ *
+ * @pdev: PCI device to create the DOE mailbox for
+ * @cap_offset: Offset of the DOE mailbox
+ *
+ * Create a single mailbox object to manage the mailbox protocol at the
+ * cap_offset specified.
+ *
+ * RETURNS: created mailbox object on success
+ * ERR_PTR(-errno) on failure
+ */
+static struct pci_doe_mb *pci_doe_create_mb(struct pci_dev *pdev,
+ u16 cap_offset)
+{
+ struct pci_doe_mb *doe_mb;
+ int rc;
+
+ doe_mb = kzalloc(sizeof(*doe_mb), GFP_KERNEL);
+ if (!doe_mb)
+ return ERR_PTR(-ENOMEM);
+
+ doe_mb->pdev = pdev;
+ doe_mb->cap_offset = cap_offset;
+ init_waitqueue_head(&doe_mb->wq);
+ xa_init(&doe_mb->prots);
+
+ doe_mb->work_queue = alloc_ordered_workqueue("%s %s DOE [%x]", 0,
+ dev_bus_name(&pdev->dev),
+ pci_name(pdev),
+ doe_mb->cap_offset);
+ if (!doe_mb->work_queue) {
+ pci_err(pdev, "[%x] failed to allocate work queue\n",
+ doe_mb->cap_offset);
+ rc = -ENOMEM;
+ goto err_free;
+ }
+
+ /* Reset the mailbox by issuing an abort */
+ rc = pci_doe_abort(doe_mb);
+ if (rc) {
+ pci_err(pdev, "[%x] failed to reset mailbox with abort command : %d\n",
+ doe_mb->cap_offset, rc);
+ goto err_destroy_wq;
+ }
+
+ /*
+ * The state machine and the mailbox should be in sync now;
+ * Use the mailbox to query protocols.
+ */
+ rc = pci_doe_cache_protocols(doe_mb);
+ if (rc) {
+ pci_err(pdev, "[%x] failed to cache protocols : %d\n",
+ doe_mb->cap_offset, rc);
+ goto err_cancel;
+ }
+
+ return doe_mb;
+
+err_cancel:
+ pci_doe_cancel_tasks(doe_mb);
+ xa_destroy(&doe_mb->prots);
+err_destroy_wq:
+ destroy_workqueue(doe_mb->work_queue);
+err_free:
+ kfree(doe_mb);
+ return ERR_PTR(rc);
+}
+
+/**
+ * pci_doe_destroy_mb() - Destroy a DOE mailbox object
+ *
+ * @doe_mb: DOE mailbox
+ *
+ * Destroy all internal data structures created for the DOE mailbox.
+ */
+static void pci_doe_destroy_mb(struct pci_doe_mb *doe_mb)
+{
+ pci_doe_cancel_tasks(doe_mb);
+ xa_destroy(&doe_mb->prots);
+ destroy_workqueue(doe_mb->work_queue);
+ kfree(doe_mb);
+}
+
+/**
+ * pci_doe_supports_prot() - Return if the DOE instance supports the given
+ * protocol
+ * @doe_mb: DOE mailbox capability to query
+ * @vid: Protocol Vendor ID
+ * @type: Protocol type
+ *
+ * RETURNS: True if the DOE mailbox supports the protocol specified
+ */
+static bool pci_doe_supports_prot(struct pci_doe_mb *doe_mb, u16 vid, u8 type)
+{
+ unsigned long index;
+ void *entry;
+
+ /* The discovery protocol must always be supported */
+ if (vid == PCI_VENDOR_ID_PCI_SIG && type == PCI_DOE_PROTOCOL_DISCOVERY)
+ return true;
+
+ xa_for_each(&doe_mb->prots, index, entry)
+ if (entry == pci_doe_xa_prot_entry(vid, type))
+ return true;
+
+ return false;
+}
+
+/**
+ * pci_doe_submit_task() - Submit a task to be processed by the state machine
+ *
+ * @doe_mb: DOE mailbox capability to submit to
+ * @task: task to be queued
+ *
+ * Submit a DOE task (request/response) to the DOE mailbox to be processed.
+ * Returns upon queueing the task object. If the queue is full this function
+ * will sleep until there is room in the queue.
+ *
+ * task->complete will be called when the state machine is done processing this
+ * task.
+ *
+ * @task must be allocated on the stack.
+ *
+ * Excess data will be discarded.
+ *
+ * RETURNS: 0 when task has been successfully queued, -ERRNO on error
+ */
+static int pci_doe_submit_task(struct pci_doe_mb *doe_mb,
+ struct pci_doe_task *task)
+{
+ if (!pci_doe_supports_prot(doe_mb, task->prot.vid, task->prot.type))
+ return -EINVAL;
+
+ if (test_bit(PCI_DOE_FLAG_DEAD, &doe_mb->flags))
+ return -EIO;
+
+ task->doe_mb = doe_mb;
+ INIT_WORK_ONSTACK(&task->work, doe_statemachine_work);
+ queue_work(doe_mb->work_queue, &task->work);
+ return 0;
+}
+
+/**
+ * pci_doe() - Perform Data Object Exchange
+ *
+ * @doe_mb: DOE Mailbox
+ * @vendor: Vendor ID
+ * @type: Data Object Type
+ * @request: Request payload
+ * @request_sz: Size of request payload (bytes)
+ * @response: Response payload
+ * @response_sz: Size of response payload (bytes)
+ *
+ * Submit @request to @doe_mb and store the @response.
+ * The DOE exchange is performed synchronously and may therefore sleep.
+ *
+ * Payloads are treated as opaque byte streams which are transmitted verbatim,
+ * without byte-swapping. If payloads contain little-endian register values,
+ * the caller is responsible for conversion with cpu_to_le32() / le32_to_cpu().
+ *
+ * For convenience, arbitrary payload sizes are allowed even though PCIe r6.0
+ * sec 6.30.1 specifies the Data Object Header 2 "Length" in dwords. The last
+ * (partial) dword is copied with byte granularity and padded with zeroes if
+ * necessary. Callers are thus relieved of using dword-sized bounce buffers.
+ *
+ * RETURNS: Length of received response or negative errno.
+ * Received data in excess of @response_sz is discarded.
+ * The length may be smaller than @response_sz and the caller
+ * is responsible for checking that.
+ */
+int pci_doe(struct pci_doe_mb *doe_mb, u16 vendor, u8 type,
+ const void *request, size_t request_sz,
+ void *response, size_t response_sz)
+{
+ DECLARE_COMPLETION_ONSTACK(c);
+ struct pci_doe_task task = {
+ .prot.vid = vendor,
+ .prot.type = type,
+ .request_pl = request,
+ .request_pl_sz = request_sz,
+ .response_pl = response,
+ .response_pl_sz = response_sz,
+ .complete = pci_doe_task_complete,
+ .private = &c,
+ };
+ int rc;
+
+ rc = pci_doe_submit_task(doe_mb, &task);
+ if (rc)
+ return rc;
+
+ wait_for_completion(&c);
+
+ return task.rv;
+}
+EXPORT_SYMBOL_GPL(pci_doe);
+
+/**
+ * pci_find_doe_mailbox() - Find Data Object Exchange mailbox
+ *
+ * @pdev: PCI device
+ * @vendor: Vendor ID
+ * @type: Data Object Type
+ *
+ * Find first DOE mailbox of a PCI device which supports the given protocol.
+ *
+ * RETURNS: Pointer to the DOE mailbox or NULL if none was found.
+ */
+struct pci_doe_mb *pci_find_doe_mailbox(struct pci_dev *pdev, u16 vendor,
+ u8 type)
+{
+ struct pci_doe_mb *doe_mb;
+ unsigned long index;
+
+ xa_for_each(&pdev->doe_mbs, index, doe_mb)
+ if (pci_doe_supports_prot(doe_mb, vendor, type))
+ return doe_mb;
+
+ return NULL;
+}
+EXPORT_SYMBOL_GPL(pci_find_doe_mailbox);
+
+void pci_doe_init(struct pci_dev *pdev)
+{
+ struct pci_doe_mb *doe_mb;
+ u16 offset = 0;
+ int rc;
+
+ xa_init(&pdev->doe_mbs);
+
+ while ((offset = pci_find_next_ext_capability(pdev, offset,
+ PCI_EXT_CAP_ID_DOE))) {
+ doe_mb = pci_doe_create_mb(pdev, offset);
+ if (IS_ERR(doe_mb)) {
+ pci_err(pdev, "[%x] failed to create mailbox: %ld\n",
+ offset, PTR_ERR(doe_mb));
+ continue;
+ }
+
+ rc = xa_insert(&pdev->doe_mbs, offset, doe_mb, GFP_KERNEL);
+ if (rc) {
+ pci_err(pdev, "[%x] failed to insert mailbox: %d\n",
+ offset, rc);
+ pci_doe_destroy_mb(doe_mb);
+ }
+ }
+}
+
+void pci_doe_destroy(struct pci_dev *pdev)
+{
+ struct pci_doe_mb *doe_mb;
+ unsigned long index;
+
+ xa_for_each(&pdev->doe_mbs, index, doe_mb)
+ pci_doe_destroy_mb(doe_mb);
+
+ xa_destroy(&pdev->doe_mbs);
+}
+
+void pci_doe_disconnected(struct pci_dev *pdev)
+{
+ struct pci_doe_mb *doe_mb;
+ unsigned long index;
+
+ xa_for_each(&pdev->doe_mbs, index, doe_mb)
+ pci_doe_cancel_tasks(doe_mb);
+}