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path: root/drivers/rpmsg/qcom_glink_native.c
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Diffstat (limited to 'drivers/rpmsg/qcom_glink_native.c')
-rw-r--r--drivers/rpmsg/qcom_glink_native.c1882
1 files changed, 1882 insertions, 0 deletions
diff --git a/drivers/rpmsg/qcom_glink_native.c b/drivers/rpmsg/qcom_glink_native.c
new file mode 100644
index 0000000000..82d460ff47
--- /dev/null
+++ b/drivers/rpmsg/qcom_glink_native.c
@@ -0,0 +1,1882 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2016-2017, Linaro Ltd
+ */
+
+#include <linux/idr.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/list.h>
+#include <linux/mfd/syscon.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/rpmsg.h>
+#include <linux/sizes.h>
+#include <linux/slab.h>
+#include <linux/wait.h>
+#include <linux/workqueue.h>
+#include <linux/mailbox_client.h>
+
+#include "rpmsg_internal.h"
+#include "qcom_glink_native.h"
+
+#define GLINK_NAME_SIZE 32
+#define GLINK_VERSION_1 1
+
+#define RPM_GLINK_CID_MIN 1
+#define RPM_GLINK_CID_MAX 65536
+
+struct glink_msg {
+ __le16 cmd;
+ __le16 param1;
+ __le32 param2;
+ u8 data[];
+} __packed;
+
+/**
+ * struct glink_defer_cmd - deferred incoming control message
+ * @node: list node
+ * @msg: message header
+ * @data: payload of the message
+ *
+ * Copy of a received control message, to be added to @rx_queue and processed
+ * by @rx_work of @qcom_glink.
+ */
+struct glink_defer_cmd {
+ struct list_head node;
+
+ struct glink_msg msg;
+ u8 data[];
+};
+
+/**
+ * struct glink_core_rx_intent - RX intent
+ * RX intent
+ *
+ * @data: pointer to the data (may be NULL for zero-copy)
+ * @id: remote or local intent ID
+ * @size: size of the original intent (do not modify)
+ * @reuse: To mark if the intent can be reused after first use
+ * @in_use: To mark if intent is already in use for the channel
+ * @offset: next write offset (initially 0)
+ * @node: list node
+ */
+struct glink_core_rx_intent {
+ void *data;
+ u32 id;
+ size_t size;
+ bool reuse;
+ bool in_use;
+ u32 offset;
+
+ struct list_head node;
+};
+
+/**
+ * struct qcom_glink - driver context, relates to one remote subsystem
+ * @dev: reference to the associated struct device
+ * @rx_pipe: pipe object for receive FIFO
+ * @tx_pipe: pipe object for transmit FIFO
+ * @rx_work: worker for handling received control messages
+ * @rx_lock: protects the @rx_queue
+ * @rx_queue: queue of received control messages to be processed in @rx_work
+ * @tx_lock: synchronizes operations on the tx fifo
+ * @idr_lock: synchronizes @lcids and @rcids modifications
+ * @lcids: idr of all channels with a known local channel id
+ * @rcids: idr of all channels with a known remote channel id
+ * @features: remote features
+ * @intentless: flag to indicate that there is no intent
+ * @tx_avail_notify: Waitqueue for pending tx tasks
+ * @sent_read_notify: flag to check cmd sent or not
+ * @abort_tx: flag indicating that all tx attempts should fail
+ */
+struct qcom_glink {
+ struct device *dev;
+
+ struct qcom_glink_pipe *rx_pipe;
+ struct qcom_glink_pipe *tx_pipe;
+
+ struct work_struct rx_work;
+ spinlock_t rx_lock;
+ struct list_head rx_queue;
+
+ spinlock_t tx_lock;
+
+ spinlock_t idr_lock;
+ struct idr lcids;
+ struct idr rcids;
+ unsigned long features;
+
+ bool intentless;
+ wait_queue_head_t tx_avail_notify;
+ bool sent_read_notify;
+
+ bool abort_tx;
+};
+
+enum {
+ GLINK_STATE_CLOSED,
+ GLINK_STATE_OPENING,
+ GLINK_STATE_OPEN,
+ GLINK_STATE_CLOSING,
+};
+
+/**
+ * struct glink_channel - internal representation of a channel
+ * @rpdev: rpdev reference, only used for primary endpoints
+ * @ept: rpmsg endpoint this channel is associated with
+ * @glink: qcom_glink context handle
+ * @refcount: refcount for the channel object
+ * @recv_lock: guard for @ept.cb
+ * @name: unique channel name/identifier
+ * @lcid: channel id, in local space
+ * @rcid: channel id, in remote space
+ * @intent_lock: lock for protection of @liids, @riids
+ * @liids: idr of all local intents
+ * @riids: idr of all remote intents
+ * @intent_work: worker responsible for transmitting rx_done packets
+ * @done_intents: list of intents that needs to be announced rx_done
+ * @buf: receive buffer, for gathering fragments
+ * @buf_offset: write offset in @buf
+ * @buf_size: size of current @buf
+ * @open_ack: completed once remote has acked the open-request
+ * @open_req: completed once open-request has been received
+ * @intent_req_lock: Synchronises multiple intent requests
+ * @intent_req_result: Result of intent request
+ * @intent_received: flag indicating that an intent has been received
+ * @intent_req_wq: wait queue for intent_req signalling
+ */
+struct glink_channel {
+ struct rpmsg_endpoint ept;
+
+ struct rpmsg_device *rpdev;
+ struct qcom_glink *glink;
+
+ struct kref refcount;
+
+ spinlock_t recv_lock;
+
+ char *name;
+ unsigned int lcid;
+ unsigned int rcid;
+
+ spinlock_t intent_lock;
+ struct idr liids;
+ struct idr riids;
+ struct work_struct intent_work;
+ struct list_head done_intents;
+
+ struct glink_core_rx_intent *buf;
+ int buf_offset;
+ int buf_size;
+
+ struct completion open_ack;
+ struct completion open_req;
+
+ struct mutex intent_req_lock;
+ int intent_req_result;
+ bool intent_received;
+ wait_queue_head_t intent_req_wq;
+};
+
+#define to_glink_channel(_ept) container_of(_ept, struct glink_channel, ept)
+
+static const struct rpmsg_endpoint_ops glink_endpoint_ops;
+
+#define GLINK_CMD_VERSION 0
+#define GLINK_CMD_VERSION_ACK 1
+#define GLINK_CMD_OPEN 2
+#define GLINK_CMD_CLOSE 3
+#define GLINK_CMD_OPEN_ACK 4
+#define GLINK_CMD_INTENT 5
+#define GLINK_CMD_RX_DONE 6
+#define GLINK_CMD_RX_INTENT_REQ 7
+#define GLINK_CMD_RX_INTENT_REQ_ACK 8
+#define GLINK_CMD_TX_DATA 9
+#define GLINK_CMD_CLOSE_ACK 11
+#define GLINK_CMD_TX_DATA_CONT 12
+#define GLINK_CMD_READ_NOTIF 13
+#define GLINK_CMD_RX_DONE_W_REUSE 14
+#define GLINK_CMD_SIGNALS 15
+
+#define GLINK_FEATURE_INTENTLESS BIT(1)
+
+#define NATIVE_DTR_SIG NATIVE_DSR_SIG
+#define NATIVE_DSR_SIG BIT(31)
+#define NATIVE_RTS_SIG NATIVE_CTS_SIG
+#define NATIVE_CTS_SIG BIT(30)
+
+static void qcom_glink_rx_done_work(struct work_struct *work);
+
+static struct glink_channel *qcom_glink_alloc_channel(struct qcom_glink *glink,
+ const char *name)
+{
+ struct glink_channel *channel;
+
+ channel = kzalloc(sizeof(*channel), GFP_KERNEL);
+ if (!channel)
+ return ERR_PTR(-ENOMEM);
+
+ /* Setup glink internal glink_channel data */
+ spin_lock_init(&channel->recv_lock);
+ spin_lock_init(&channel->intent_lock);
+ mutex_init(&channel->intent_req_lock);
+
+ channel->glink = glink;
+ channel->name = kstrdup(name, GFP_KERNEL);
+ if (!channel->name) {
+ kfree(channel);
+ return ERR_PTR(-ENOMEM);
+ }
+
+ init_completion(&channel->open_req);
+ init_completion(&channel->open_ack);
+ init_waitqueue_head(&channel->intent_req_wq);
+
+ INIT_LIST_HEAD(&channel->done_intents);
+ INIT_WORK(&channel->intent_work, qcom_glink_rx_done_work);
+
+ idr_init(&channel->liids);
+ idr_init(&channel->riids);
+ kref_init(&channel->refcount);
+
+ return channel;
+}
+
+static void qcom_glink_channel_release(struct kref *ref)
+{
+ struct glink_channel *channel = container_of(ref, struct glink_channel,
+ refcount);
+ struct glink_core_rx_intent *intent;
+ struct glink_core_rx_intent *tmp;
+ unsigned long flags;
+ int iid;
+
+ /* cancel pending rx_done work */
+ cancel_work_sync(&channel->intent_work);
+
+ spin_lock_irqsave(&channel->intent_lock, flags);
+ /* Free all non-reuse intents pending rx_done work */
+ list_for_each_entry_safe(intent, tmp, &channel->done_intents, node) {
+ if (!intent->reuse) {
+ kfree(intent->data);
+ kfree(intent);
+ }
+ }
+
+ idr_for_each_entry(&channel->liids, tmp, iid) {
+ kfree(tmp->data);
+ kfree(tmp);
+ }
+ idr_destroy(&channel->liids);
+
+ idr_for_each_entry(&channel->riids, tmp, iid)
+ kfree(tmp);
+ idr_destroy(&channel->riids);
+ spin_unlock_irqrestore(&channel->intent_lock, flags);
+
+ kfree(channel->name);
+ kfree(channel);
+}
+
+static size_t qcom_glink_rx_avail(struct qcom_glink *glink)
+{
+ return glink->rx_pipe->avail(glink->rx_pipe);
+}
+
+static void qcom_glink_rx_peek(struct qcom_glink *glink,
+ void *data, unsigned int offset, size_t count)
+{
+ glink->rx_pipe->peek(glink->rx_pipe, data, offset, count);
+}
+
+static void qcom_glink_rx_advance(struct qcom_glink *glink, size_t count)
+{
+ glink->rx_pipe->advance(glink->rx_pipe, count);
+}
+
+static size_t qcom_glink_tx_avail(struct qcom_glink *glink)
+{
+ return glink->tx_pipe->avail(glink->tx_pipe);
+}
+
+static void qcom_glink_tx_write(struct qcom_glink *glink,
+ const void *hdr, size_t hlen,
+ const void *data, size_t dlen)
+{
+ glink->tx_pipe->write(glink->tx_pipe, hdr, hlen, data, dlen);
+}
+
+static void qcom_glink_tx_kick(struct qcom_glink *glink)
+{
+ glink->tx_pipe->kick(glink->tx_pipe);
+}
+
+static void qcom_glink_send_read_notify(struct qcom_glink *glink)
+{
+ struct glink_msg msg;
+
+ msg.cmd = cpu_to_le16(GLINK_CMD_READ_NOTIF);
+ msg.param1 = 0;
+ msg.param2 = 0;
+
+ qcom_glink_tx_write(glink, &msg, sizeof(msg), NULL, 0);
+
+ qcom_glink_tx_kick(glink);
+}
+
+static int qcom_glink_tx(struct qcom_glink *glink,
+ const void *hdr, size_t hlen,
+ const void *data, size_t dlen, bool wait)
+{
+ unsigned int tlen = hlen + dlen;
+ unsigned long flags;
+ int ret = 0;
+
+ /* Reject packets that are too big */
+ if (tlen >= glink->tx_pipe->length)
+ return -EINVAL;
+
+ spin_lock_irqsave(&glink->tx_lock, flags);
+
+ if (glink->abort_tx) {
+ ret = -EIO;
+ goto out;
+ }
+
+ while (qcom_glink_tx_avail(glink) < tlen) {
+ if (!wait) {
+ ret = -EAGAIN;
+ goto out;
+ }
+
+ if (glink->abort_tx) {
+ ret = -EIO;
+ goto out;
+ }
+
+ if (!glink->sent_read_notify) {
+ glink->sent_read_notify = true;
+ qcom_glink_send_read_notify(glink);
+ }
+
+ /* Wait without holding the tx_lock */
+ spin_unlock_irqrestore(&glink->tx_lock, flags);
+
+ wait_event_timeout(glink->tx_avail_notify,
+ qcom_glink_tx_avail(glink) >= tlen, 10 * HZ);
+
+ spin_lock_irqsave(&glink->tx_lock, flags);
+
+ if (qcom_glink_tx_avail(glink) >= tlen)
+ glink->sent_read_notify = false;
+ }
+
+ qcom_glink_tx_write(glink, hdr, hlen, data, dlen);
+ qcom_glink_tx_kick(glink);
+
+out:
+ spin_unlock_irqrestore(&glink->tx_lock, flags);
+
+ return ret;
+}
+
+static int qcom_glink_send_version(struct qcom_glink *glink)
+{
+ struct glink_msg msg;
+
+ msg.cmd = cpu_to_le16(GLINK_CMD_VERSION);
+ msg.param1 = cpu_to_le16(GLINK_VERSION_1);
+ msg.param2 = cpu_to_le32(glink->features);
+
+ return qcom_glink_tx(glink, &msg, sizeof(msg), NULL, 0, true);
+}
+
+static void qcom_glink_send_version_ack(struct qcom_glink *glink)
+{
+ struct glink_msg msg;
+
+ msg.cmd = cpu_to_le16(GLINK_CMD_VERSION_ACK);
+ msg.param1 = cpu_to_le16(GLINK_VERSION_1);
+ msg.param2 = cpu_to_le32(glink->features);
+
+ qcom_glink_tx(glink, &msg, sizeof(msg), NULL, 0, true);
+}
+
+static void qcom_glink_send_open_ack(struct qcom_glink *glink,
+ struct glink_channel *channel)
+{
+ struct glink_msg msg;
+
+ msg.cmd = cpu_to_le16(GLINK_CMD_OPEN_ACK);
+ msg.param1 = cpu_to_le16(channel->rcid);
+ msg.param2 = cpu_to_le32(0);
+
+ qcom_glink_tx(glink, &msg, sizeof(msg), NULL, 0, true);
+}
+
+static void qcom_glink_handle_intent_req_ack(struct qcom_glink *glink,
+ unsigned int cid, bool granted)
+{
+ struct glink_channel *channel;
+ unsigned long flags;
+
+ spin_lock_irqsave(&glink->idr_lock, flags);
+ channel = idr_find(&glink->rcids, cid);
+ spin_unlock_irqrestore(&glink->idr_lock, flags);
+ if (!channel) {
+ dev_err(glink->dev, "unable to find channel\n");
+ return;
+ }
+
+ WRITE_ONCE(channel->intent_req_result, granted);
+ wake_up_all(&channel->intent_req_wq);
+}
+
+static void qcom_glink_intent_req_abort(struct glink_channel *channel)
+{
+ WRITE_ONCE(channel->intent_req_result, 0);
+ wake_up_all(&channel->intent_req_wq);
+}
+
+/**
+ * qcom_glink_send_open_req() - send a GLINK_CMD_OPEN request to the remote
+ * @glink: Ptr to the glink edge
+ * @channel: Ptr to the channel that the open req is sent
+ *
+ * Allocates a local channel id and sends a GLINK_CMD_OPEN message to the remote.
+ * Will return with refcount held, regardless of outcome.
+ *
+ * Return: 0 on success, negative errno otherwise.
+ */
+static int qcom_glink_send_open_req(struct qcom_glink *glink,
+ struct glink_channel *channel)
+{
+ struct {
+ struct glink_msg msg;
+ u8 name[GLINK_NAME_SIZE];
+ } __packed req;
+ int name_len = strlen(channel->name) + 1;
+ int req_len = ALIGN(sizeof(req.msg) + name_len, 8);
+ int ret;
+ unsigned long flags;
+
+ kref_get(&channel->refcount);
+
+ spin_lock_irqsave(&glink->idr_lock, flags);
+ ret = idr_alloc_cyclic(&glink->lcids, channel,
+ RPM_GLINK_CID_MIN, RPM_GLINK_CID_MAX,
+ GFP_ATOMIC);
+ spin_unlock_irqrestore(&glink->idr_lock, flags);
+ if (ret < 0)
+ return ret;
+
+ channel->lcid = ret;
+
+ req.msg.cmd = cpu_to_le16(GLINK_CMD_OPEN);
+ req.msg.param1 = cpu_to_le16(channel->lcid);
+ req.msg.param2 = cpu_to_le32(name_len);
+ strcpy(req.name, channel->name);
+
+ ret = qcom_glink_tx(glink, &req, req_len, NULL, 0, true);
+ if (ret)
+ goto remove_idr;
+
+ return 0;
+
+remove_idr:
+ spin_lock_irqsave(&glink->idr_lock, flags);
+ idr_remove(&glink->lcids, channel->lcid);
+ channel->lcid = 0;
+ spin_unlock_irqrestore(&glink->idr_lock, flags);
+
+ return ret;
+}
+
+static void qcom_glink_send_close_req(struct qcom_glink *glink,
+ struct glink_channel *channel)
+{
+ struct glink_msg req;
+
+ req.cmd = cpu_to_le16(GLINK_CMD_CLOSE);
+ req.param1 = cpu_to_le16(channel->lcid);
+ req.param2 = 0;
+
+ qcom_glink_tx(glink, &req, sizeof(req), NULL, 0, true);
+}
+
+static void qcom_glink_send_close_ack(struct qcom_glink *glink,
+ unsigned int rcid)
+{
+ struct glink_msg req;
+
+ req.cmd = cpu_to_le16(GLINK_CMD_CLOSE_ACK);
+ req.param1 = cpu_to_le16(rcid);
+ req.param2 = 0;
+
+ qcom_glink_tx(glink, &req, sizeof(req), NULL, 0, true);
+}
+
+static void qcom_glink_rx_done_work(struct work_struct *work)
+{
+ struct glink_channel *channel = container_of(work, struct glink_channel,
+ intent_work);
+ struct qcom_glink *glink = channel->glink;
+ struct glink_core_rx_intent *intent, *tmp;
+ struct {
+ u16 id;
+ u16 lcid;
+ u32 liid;
+ } __packed cmd;
+
+ unsigned int cid = channel->lcid;
+ unsigned int iid;
+ bool reuse;
+ unsigned long flags;
+
+ spin_lock_irqsave(&channel->intent_lock, flags);
+ list_for_each_entry_safe(intent, tmp, &channel->done_intents, node) {
+ list_del(&intent->node);
+ spin_unlock_irqrestore(&channel->intent_lock, flags);
+ iid = intent->id;
+ reuse = intent->reuse;
+
+ cmd.id = reuse ? GLINK_CMD_RX_DONE_W_REUSE : GLINK_CMD_RX_DONE;
+ cmd.lcid = cid;
+ cmd.liid = iid;
+
+ qcom_glink_tx(glink, &cmd, sizeof(cmd), NULL, 0, true);
+ if (!reuse) {
+ kfree(intent->data);
+ kfree(intent);
+ }
+ spin_lock_irqsave(&channel->intent_lock, flags);
+ }
+ spin_unlock_irqrestore(&channel->intent_lock, flags);
+}
+
+static void qcom_glink_rx_done(struct qcom_glink *glink,
+ struct glink_channel *channel,
+ struct glink_core_rx_intent *intent)
+{
+ /* We don't send RX_DONE to intentless systems */
+ if (glink->intentless) {
+ kfree(intent->data);
+ kfree(intent);
+ return;
+ }
+
+ /* Take it off the tree of receive intents */
+ if (!intent->reuse) {
+ spin_lock(&channel->intent_lock);
+ idr_remove(&channel->liids, intent->id);
+ spin_unlock(&channel->intent_lock);
+ }
+
+ /* Schedule the sending of a rx_done indication */
+ spin_lock(&channel->intent_lock);
+ list_add_tail(&intent->node, &channel->done_intents);
+ spin_unlock(&channel->intent_lock);
+
+ schedule_work(&channel->intent_work);
+}
+
+/**
+ * qcom_glink_receive_version() - receive version/features from remote system
+ *
+ * @glink: pointer to transport interface
+ * @version: remote version
+ * @features: remote features
+ *
+ * This function is called in response to a remote-initiated version/feature
+ * negotiation sequence.
+ */
+static void qcom_glink_receive_version(struct qcom_glink *glink,
+ u32 version,
+ u32 features)
+{
+ switch (version) {
+ case 0:
+ break;
+ case GLINK_VERSION_1:
+ glink->features &= features;
+ fallthrough;
+ default:
+ qcom_glink_send_version_ack(glink);
+ break;
+ }
+}
+
+/**
+ * qcom_glink_receive_version_ack() - receive negotiation ack from remote system
+ *
+ * @glink: pointer to transport interface
+ * @version: remote version response
+ * @features: remote features response
+ *
+ * This function is called in response to a local-initiated version/feature
+ * negotiation sequence and is the counter-offer from the remote side based
+ * upon the initial version and feature set requested.
+ */
+static void qcom_glink_receive_version_ack(struct qcom_glink *glink,
+ u32 version,
+ u32 features)
+{
+ switch (version) {
+ case 0:
+ /* Version negotiation failed */
+ break;
+ case GLINK_VERSION_1:
+ if (features == glink->features)
+ break;
+
+ glink->features &= features;
+ fallthrough;
+ default:
+ qcom_glink_send_version(glink);
+ break;
+ }
+}
+
+/**
+ * qcom_glink_send_intent_req_ack() - convert an rx intent request ack cmd to
+ * wire format and transmit
+ * @glink: The transport to transmit on.
+ * @channel: The glink channel
+ * @granted: The request response to encode.
+ *
+ * Return: 0 on success or standard Linux error code.
+ */
+static int qcom_glink_send_intent_req_ack(struct qcom_glink *glink,
+ struct glink_channel *channel,
+ bool granted)
+{
+ struct glink_msg msg;
+
+ msg.cmd = cpu_to_le16(GLINK_CMD_RX_INTENT_REQ_ACK);
+ msg.param1 = cpu_to_le16(channel->lcid);
+ msg.param2 = cpu_to_le32(granted);
+
+ qcom_glink_tx(glink, &msg, sizeof(msg), NULL, 0, true);
+
+ return 0;
+}
+
+/**
+ * qcom_glink_advertise_intent - convert an rx intent cmd to wire format and
+ * transmit
+ * @glink: The transport to transmit on.
+ * @channel: The local channel
+ * @intent: The intent to pass on to remote.
+ *
+ * Return: 0 on success or standard Linux error code.
+ */
+static int qcom_glink_advertise_intent(struct qcom_glink *glink,
+ struct glink_channel *channel,
+ struct glink_core_rx_intent *intent)
+{
+ struct command {
+ __le16 id;
+ __le16 lcid;
+ __le32 count;
+ __le32 size;
+ __le32 liid;
+ } __packed;
+ struct command cmd;
+
+ cmd.id = cpu_to_le16(GLINK_CMD_INTENT);
+ cmd.lcid = cpu_to_le16(channel->lcid);
+ cmd.count = cpu_to_le32(1);
+ cmd.size = cpu_to_le32(intent->size);
+ cmd.liid = cpu_to_le32(intent->id);
+
+ qcom_glink_tx(glink, &cmd, sizeof(cmd), NULL, 0, true);
+
+ return 0;
+}
+
+static struct glink_core_rx_intent *
+qcom_glink_alloc_intent(struct qcom_glink *glink,
+ struct glink_channel *channel,
+ size_t size,
+ bool reuseable)
+{
+ struct glink_core_rx_intent *intent;
+ int ret;
+ unsigned long flags;
+
+ intent = kzalloc(sizeof(*intent), GFP_KERNEL);
+ if (!intent)
+ return NULL;
+
+ intent->data = kzalloc(size, GFP_KERNEL);
+ if (!intent->data)
+ goto free_intent;
+
+ spin_lock_irqsave(&channel->intent_lock, flags);
+ ret = idr_alloc_cyclic(&channel->liids, intent, 1, -1, GFP_ATOMIC);
+ if (ret < 0) {
+ spin_unlock_irqrestore(&channel->intent_lock, flags);
+ goto free_data;
+ }
+ spin_unlock_irqrestore(&channel->intent_lock, flags);
+
+ intent->id = ret;
+ intent->size = size;
+ intent->reuse = reuseable;
+
+ return intent;
+
+free_data:
+ kfree(intent->data);
+free_intent:
+ kfree(intent);
+ return NULL;
+}
+
+static void qcom_glink_handle_rx_done(struct qcom_glink *glink,
+ u32 cid, uint32_t iid,
+ bool reuse)
+{
+ struct glink_core_rx_intent *intent;
+ struct glink_channel *channel;
+ unsigned long flags;
+
+ spin_lock_irqsave(&glink->idr_lock, flags);
+ channel = idr_find(&glink->rcids, cid);
+ spin_unlock_irqrestore(&glink->idr_lock, flags);
+ if (!channel) {
+ dev_err(glink->dev, "invalid channel id received\n");
+ return;
+ }
+
+ spin_lock_irqsave(&channel->intent_lock, flags);
+ intent = idr_find(&channel->riids, iid);
+
+ if (!intent) {
+ spin_unlock_irqrestore(&channel->intent_lock, flags);
+ dev_err(glink->dev, "invalid intent id received\n");
+ return;
+ }
+
+ intent->in_use = false;
+
+ if (!reuse) {
+ idr_remove(&channel->riids, intent->id);
+ kfree(intent);
+ }
+ spin_unlock_irqrestore(&channel->intent_lock, flags);
+
+ if (reuse) {
+ WRITE_ONCE(channel->intent_received, true);
+ wake_up_all(&channel->intent_req_wq);
+ }
+}
+
+/**
+ * qcom_glink_handle_intent_req() - Receive a request for rx_intent
+ * from remote side
+ * @glink: Pointer to the transport interface
+ * @cid: Remote channel ID
+ * @size: size of the intent
+ *
+ * The function searches for the local channel to which the request for
+ * rx_intent has arrived and allocates and notifies the remote back
+ */
+static void qcom_glink_handle_intent_req(struct qcom_glink *glink,
+ u32 cid, size_t size)
+{
+ struct glink_core_rx_intent *intent;
+ struct glink_channel *channel;
+ unsigned long flags;
+
+ spin_lock_irqsave(&glink->idr_lock, flags);
+ channel = idr_find(&glink->rcids, cid);
+ spin_unlock_irqrestore(&glink->idr_lock, flags);
+
+ if (!channel) {
+ pr_err("%s channel not found for cid %d\n", __func__, cid);
+ return;
+ }
+
+ intent = qcom_glink_alloc_intent(glink, channel, size, false);
+ if (intent)
+ qcom_glink_advertise_intent(glink, channel, intent);
+
+ qcom_glink_send_intent_req_ack(glink, channel, !!intent);
+}
+
+static int qcom_glink_rx_defer(struct qcom_glink *glink, size_t extra)
+{
+ struct glink_defer_cmd *dcmd;
+
+ extra = ALIGN(extra, 8);
+
+ if (qcom_glink_rx_avail(glink) < sizeof(struct glink_msg) + extra) {
+ dev_dbg(glink->dev, "Insufficient data in rx fifo");
+ return -ENXIO;
+ }
+
+ dcmd = kzalloc(struct_size(dcmd, data, extra), GFP_ATOMIC);
+ if (!dcmd)
+ return -ENOMEM;
+
+ INIT_LIST_HEAD(&dcmd->node);
+
+ qcom_glink_rx_peek(glink, &dcmd->msg, 0, sizeof(dcmd->msg) + extra);
+
+ spin_lock(&glink->rx_lock);
+ list_add_tail(&dcmd->node, &glink->rx_queue);
+ spin_unlock(&glink->rx_lock);
+
+ schedule_work(&glink->rx_work);
+ qcom_glink_rx_advance(glink, sizeof(dcmd->msg) + extra);
+
+ return 0;
+}
+
+static int qcom_glink_rx_data(struct qcom_glink *glink, size_t avail)
+{
+ struct glink_core_rx_intent *intent;
+ struct glink_channel *channel;
+ struct {
+ struct glink_msg msg;
+ __le32 chunk_size;
+ __le32 left_size;
+ } __packed hdr;
+ unsigned int chunk_size;
+ unsigned int left_size;
+ unsigned int rcid;
+ unsigned int liid;
+ int ret = 0;
+ unsigned long flags;
+
+ if (avail < sizeof(hdr)) {
+ dev_dbg(glink->dev, "Not enough data in fifo\n");
+ return -EAGAIN;
+ }
+
+ qcom_glink_rx_peek(glink, &hdr, 0, sizeof(hdr));
+ chunk_size = le32_to_cpu(hdr.chunk_size);
+ left_size = le32_to_cpu(hdr.left_size);
+
+ if (avail < sizeof(hdr) + chunk_size) {
+ dev_dbg(glink->dev, "Payload not yet in fifo\n");
+ return -EAGAIN;
+ }
+
+ rcid = le16_to_cpu(hdr.msg.param1);
+ spin_lock_irqsave(&glink->idr_lock, flags);
+ channel = idr_find(&glink->rcids, rcid);
+ spin_unlock_irqrestore(&glink->idr_lock, flags);
+ if (!channel) {
+ dev_dbg(glink->dev, "Data on non-existing channel\n");
+
+ /* Drop the message */
+ goto advance_rx;
+ }
+
+ if (glink->intentless) {
+ /* Might have an ongoing, fragmented, message to append */
+ if (!channel->buf) {
+ intent = kzalloc(sizeof(*intent), GFP_ATOMIC);
+ if (!intent)
+ return -ENOMEM;
+
+ intent->data = kmalloc(chunk_size + left_size,
+ GFP_ATOMIC);
+ if (!intent->data) {
+ kfree(intent);
+ return -ENOMEM;
+ }
+
+ intent->id = 0xbabababa;
+ intent->size = chunk_size + left_size;
+ intent->offset = 0;
+
+ channel->buf = intent;
+ } else {
+ intent = channel->buf;
+ }
+ } else {
+ liid = le32_to_cpu(hdr.msg.param2);
+
+ spin_lock_irqsave(&channel->intent_lock, flags);
+ intent = idr_find(&channel->liids, liid);
+ spin_unlock_irqrestore(&channel->intent_lock, flags);
+
+ if (!intent) {
+ dev_err(glink->dev,
+ "no intent found for channel %s intent %d",
+ channel->name, liid);
+ ret = -ENOENT;
+ goto advance_rx;
+ }
+ }
+
+ if (intent->size - intent->offset < chunk_size) {
+ dev_err(glink->dev, "Insufficient space in intent\n");
+
+ /* The packet header lied, drop payload */
+ goto advance_rx;
+ }
+
+ qcom_glink_rx_peek(glink, intent->data + intent->offset,
+ sizeof(hdr), chunk_size);
+ intent->offset += chunk_size;
+
+ /* Handle message when no fragments remain to be received */
+ if (!left_size) {
+ spin_lock(&channel->recv_lock);
+ if (channel->ept.cb) {
+ channel->ept.cb(channel->ept.rpdev,
+ intent->data,
+ intent->offset,
+ channel->ept.priv,
+ RPMSG_ADDR_ANY);
+ }
+ spin_unlock(&channel->recv_lock);
+
+ intent->offset = 0;
+ channel->buf = NULL;
+
+ qcom_glink_rx_done(glink, channel, intent);
+ }
+
+advance_rx:
+ qcom_glink_rx_advance(glink, ALIGN(sizeof(hdr) + chunk_size, 8));
+
+ return ret;
+}
+
+static void qcom_glink_handle_intent(struct qcom_glink *glink,
+ unsigned int cid,
+ unsigned int count,
+ size_t avail)
+{
+ struct glink_core_rx_intent *intent;
+ struct glink_channel *channel;
+ struct intent_pair {
+ __le32 size;
+ __le32 iid;
+ };
+
+ struct {
+ struct glink_msg msg;
+ struct intent_pair intents[];
+ } __packed * msg;
+
+ const size_t msglen = struct_size(msg, intents, count);
+ int ret;
+ int i;
+ unsigned long flags;
+
+ if (avail < msglen) {
+ dev_dbg(glink->dev, "Not enough data in fifo\n");
+ return;
+ }
+
+ spin_lock_irqsave(&glink->idr_lock, flags);
+ channel = idr_find(&glink->rcids, cid);
+ spin_unlock_irqrestore(&glink->idr_lock, flags);
+ if (!channel) {
+ dev_err(glink->dev, "intents for non-existing channel\n");
+ qcom_glink_rx_advance(glink, ALIGN(msglen, 8));
+ return;
+ }
+
+ msg = kmalloc(msglen, GFP_ATOMIC);
+ if (!msg)
+ return;
+
+ qcom_glink_rx_peek(glink, msg, 0, msglen);
+
+ for (i = 0; i < count; ++i) {
+ intent = kzalloc(sizeof(*intent), GFP_ATOMIC);
+ if (!intent)
+ break;
+
+ intent->id = le32_to_cpu(msg->intents[i].iid);
+ intent->size = le32_to_cpu(msg->intents[i].size);
+
+ spin_lock_irqsave(&channel->intent_lock, flags);
+ ret = idr_alloc(&channel->riids, intent,
+ intent->id, intent->id + 1, GFP_ATOMIC);
+ spin_unlock_irqrestore(&channel->intent_lock, flags);
+
+ if (ret < 0)
+ dev_err(glink->dev, "failed to store remote intent\n");
+ }
+
+ WRITE_ONCE(channel->intent_received, true);
+ wake_up_all(&channel->intent_req_wq);
+
+ kfree(msg);
+ qcom_glink_rx_advance(glink, ALIGN(msglen, 8));
+}
+
+static int qcom_glink_rx_open_ack(struct qcom_glink *glink, unsigned int lcid)
+{
+ struct glink_channel *channel;
+
+ spin_lock(&glink->idr_lock);
+ channel = idr_find(&glink->lcids, lcid);
+ spin_unlock(&glink->idr_lock);
+ if (!channel) {
+ dev_err(glink->dev, "Invalid open ack packet\n");
+ return -EINVAL;
+ }
+
+ complete_all(&channel->open_ack);
+
+ return 0;
+}
+
+/**
+ * qcom_glink_set_flow_control() - convert a signal cmd to wire format and transmit
+ * @ept: Rpmsg endpoint for channel.
+ * @pause: Pause transmission
+ * @dst: destination address of the endpoint
+ *
+ * Return: 0 on success or standard Linux error code.
+ */
+static int qcom_glink_set_flow_control(struct rpmsg_endpoint *ept, bool pause, u32 dst)
+{
+ struct glink_channel *channel = to_glink_channel(ept);
+ struct qcom_glink *glink = channel->glink;
+ struct glink_msg msg;
+ u32 sigs = 0;
+
+ if (pause)
+ sigs |= NATIVE_DTR_SIG | NATIVE_RTS_SIG;
+
+ msg.cmd = cpu_to_le16(GLINK_CMD_SIGNALS);
+ msg.param1 = cpu_to_le16(channel->lcid);
+ msg.param2 = cpu_to_le32(sigs);
+
+ return qcom_glink_tx(glink, &msg, sizeof(msg), NULL, 0, true);
+}
+
+static void qcom_glink_handle_signals(struct qcom_glink *glink,
+ unsigned int rcid, unsigned int sigs)
+{
+ struct glink_channel *channel;
+ unsigned long flags;
+ bool enable;
+
+ spin_lock_irqsave(&glink->idr_lock, flags);
+ channel = idr_find(&glink->rcids, rcid);
+ spin_unlock_irqrestore(&glink->idr_lock, flags);
+ if (!channel) {
+ dev_err(glink->dev, "signal for non-existing channel\n");
+ return;
+ }
+
+ enable = sigs & NATIVE_DSR_SIG || sigs & NATIVE_CTS_SIG;
+
+ if (channel->ept.flow_cb)
+ channel->ept.flow_cb(channel->ept.rpdev, channel->ept.priv, enable);
+}
+
+void qcom_glink_native_rx(struct qcom_glink *glink)
+{
+ struct glink_msg msg;
+ unsigned int param1;
+ unsigned int param2;
+ unsigned int avail;
+ unsigned int cmd;
+ int ret = 0;
+
+ /* To wakeup any blocking writers */
+ wake_up_all(&glink->tx_avail_notify);
+
+ for (;;) {
+ avail = qcom_glink_rx_avail(glink);
+ if (avail < sizeof(msg))
+ break;
+
+ qcom_glink_rx_peek(glink, &msg, 0, sizeof(msg));
+
+ cmd = le16_to_cpu(msg.cmd);
+ param1 = le16_to_cpu(msg.param1);
+ param2 = le32_to_cpu(msg.param2);
+
+ switch (cmd) {
+ case GLINK_CMD_VERSION:
+ case GLINK_CMD_VERSION_ACK:
+ case GLINK_CMD_CLOSE:
+ case GLINK_CMD_CLOSE_ACK:
+ case GLINK_CMD_RX_INTENT_REQ:
+ ret = qcom_glink_rx_defer(glink, 0);
+ break;
+ case GLINK_CMD_OPEN_ACK:
+ ret = qcom_glink_rx_open_ack(glink, param1);
+ qcom_glink_rx_advance(glink, ALIGN(sizeof(msg), 8));
+ break;
+ case GLINK_CMD_OPEN:
+ ret = qcom_glink_rx_defer(glink, param2);
+ break;
+ case GLINK_CMD_TX_DATA:
+ case GLINK_CMD_TX_DATA_CONT:
+ ret = qcom_glink_rx_data(glink, avail);
+ break;
+ case GLINK_CMD_READ_NOTIF:
+ qcom_glink_rx_advance(glink, ALIGN(sizeof(msg), 8));
+ qcom_glink_tx_kick(glink);
+ break;
+ case GLINK_CMD_INTENT:
+ qcom_glink_handle_intent(glink, param1, param2, avail);
+ break;
+ case GLINK_CMD_RX_DONE:
+ qcom_glink_handle_rx_done(glink, param1, param2, false);
+ qcom_glink_rx_advance(glink, ALIGN(sizeof(msg), 8));
+ break;
+ case GLINK_CMD_RX_DONE_W_REUSE:
+ qcom_glink_handle_rx_done(glink, param1, param2, true);
+ qcom_glink_rx_advance(glink, ALIGN(sizeof(msg), 8));
+ break;
+ case GLINK_CMD_RX_INTENT_REQ_ACK:
+ qcom_glink_handle_intent_req_ack(glink, param1, param2);
+ qcom_glink_rx_advance(glink, ALIGN(sizeof(msg), 8));
+ break;
+ case GLINK_CMD_SIGNALS:
+ qcom_glink_handle_signals(glink, param1, param2);
+ qcom_glink_rx_advance(glink, ALIGN(sizeof(msg), 8));
+ break;
+ default:
+ dev_err(glink->dev, "unhandled rx cmd: %d\n", cmd);
+ ret = -EINVAL;
+ break;
+ }
+
+ if (ret)
+ break;
+ }
+}
+EXPORT_SYMBOL(qcom_glink_native_rx);
+
+/* Locally initiated rpmsg_create_ept */
+static struct glink_channel *qcom_glink_create_local(struct qcom_glink *glink,
+ const char *name)
+{
+ struct glink_channel *channel;
+ int ret;
+ unsigned long flags;
+
+ channel = qcom_glink_alloc_channel(glink, name);
+ if (IS_ERR(channel))
+ return ERR_CAST(channel);
+
+ ret = qcom_glink_send_open_req(glink, channel);
+ if (ret)
+ goto release_channel;
+
+ ret = wait_for_completion_timeout(&channel->open_ack, 5 * HZ);
+ if (!ret)
+ goto err_timeout;
+
+ ret = wait_for_completion_timeout(&channel->open_req, 5 * HZ);
+ if (!ret)
+ goto err_timeout;
+
+ qcom_glink_send_open_ack(glink, channel);
+
+ return channel;
+
+err_timeout:
+ /* qcom_glink_send_open_req() did register the channel in lcids*/
+ spin_lock_irqsave(&glink->idr_lock, flags);
+ idr_remove(&glink->lcids, channel->lcid);
+ spin_unlock_irqrestore(&glink->idr_lock, flags);
+
+release_channel:
+ /* Release qcom_glink_send_open_req() reference */
+ kref_put(&channel->refcount, qcom_glink_channel_release);
+ /* Release qcom_glink_alloc_channel() reference */
+ kref_put(&channel->refcount, qcom_glink_channel_release);
+
+ return ERR_PTR(-ETIMEDOUT);
+}
+
+/* Remote initiated rpmsg_create_ept */
+static int qcom_glink_create_remote(struct qcom_glink *glink,
+ struct glink_channel *channel)
+{
+ int ret;
+
+ qcom_glink_send_open_ack(glink, channel);
+
+ ret = qcom_glink_send_open_req(glink, channel);
+ if (ret)
+ goto close_link;
+
+ ret = wait_for_completion_timeout(&channel->open_ack, 5 * HZ);
+ if (!ret) {
+ ret = -ETIMEDOUT;
+ goto close_link;
+ }
+
+ return 0;
+
+close_link:
+ /*
+ * Send a close request to "undo" our open-ack. The close-ack will
+ * release qcom_glink_send_open_req() reference and the last reference
+ * will be relesed after receiving remote_close or transport unregister
+ * by calling qcom_glink_native_remove().
+ */
+ qcom_glink_send_close_req(glink, channel);
+
+ return ret;
+}
+
+static struct rpmsg_endpoint *qcom_glink_create_ept(struct rpmsg_device *rpdev,
+ rpmsg_rx_cb_t cb,
+ void *priv,
+ struct rpmsg_channel_info
+ chinfo)
+{
+ struct glink_channel *parent = to_glink_channel(rpdev->ept);
+ struct glink_channel *channel;
+ struct qcom_glink *glink = parent->glink;
+ struct rpmsg_endpoint *ept;
+ const char *name = chinfo.name;
+ int cid;
+ int ret;
+ unsigned long flags;
+
+ spin_lock_irqsave(&glink->idr_lock, flags);
+ idr_for_each_entry(&glink->rcids, channel, cid) {
+ if (!strcmp(channel->name, name))
+ break;
+ }
+ spin_unlock_irqrestore(&glink->idr_lock, flags);
+
+ if (!channel) {
+ channel = qcom_glink_create_local(glink, name);
+ if (IS_ERR(channel))
+ return NULL;
+ } else {
+ ret = qcom_glink_create_remote(glink, channel);
+ if (ret)
+ return NULL;
+ }
+
+ ept = &channel->ept;
+ ept->rpdev = rpdev;
+ ept->cb = cb;
+ ept->priv = priv;
+ ept->ops = &glink_endpoint_ops;
+
+ return ept;
+}
+
+static int qcom_glink_announce_create(struct rpmsg_device *rpdev)
+{
+ struct glink_channel *channel = to_glink_channel(rpdev->ept);
+ struct device_node *np = rpdev->dev.of_node;
+ struct qcom_glink *glink = channel->glink;
+ struct glink_core_rx_intent *intent;
+ const struct property *prop = NULL;
+ __be32 defaults[] = { cpu_to_be32(SZ_1K), cpu_to_be32(5) };
+ int num_intents;
+ int num_groups = 1;
+ __be32 *val = defaults;
+ int size;
+
+ if (glink->intentless || !completion_done(&channel->open_ack))
+ return 0;
+
+ prop = of_find_property(np, "qcom,intents", NULL);
+ if (prop) {
+ val = prop->value;
+ num_groups = prop->length / sizeof(u32) / 2;
+ }
+
+ /* Channel is now open, advertise base set of intents */
+ while (num_groups--) {
+ size = be32_to_cpup(val++);
+ num_intents = be32_to_cpup(val++);
+ while (num_intents--) {
+ intent = qcom_glink_alloc_intent(glink, channel, size,
+ true);
+ if (!intent)
+ break;
+
+ qcom_glink_advertise_intent(glink, channel, intent);
+ }
+ }
+ return 0;
+}
+
+static void qcom_glink_destroy_ept(struct rpmsg_endpoint *ept)
+{
+ struct glink_channel *channel = to_glink_channel(ept);
+ struct qcom_glink *glink = channel->glink;
+ unsigned long flags;
+
+ spin_lock_irqsave(&channel->recv_lock, flags);
+ channel->ept.cb = NULL;
+ spin_unlock_irqrestore(&channel->recv_lock, flags);
+
+ /* Decouple the potential rpdev from the channel */
+ channel->rpdev = NULL;
+
+ qcom_glink_send_close_req(glink, channel);
+}
+
+static int qcom_glink_request_intent(struct qcom_glink *glink,
+ struct glink_channel *channel,
+ size_t size)
+{
+ struct {
+ u16 id;
+ u16 cid;
+ u32 size;
+ } __packed cmd;
+
+ int ret;
+
+ mutex_lock(&channel->intent_req_lock);
+
+ WRITE_ONCE(channel->intent_req_result, -1);
+ WRITE_ONCE(channel->intent_received, false);
+
+ cmd.id = GLINK_CMD_RX_INTENT_REQ;
+ cmd.cid = channel->lcid;
+ cmd.size = size;
+
+ ret = qcom_glink_tx(glink, &cmd, sizeof(cmd), NULL, 0, true);
+ if (ret)
+ goto unlock;
+
+ ret = wait_event_timeout(channel->intent_req_wq,
+ READ_ONCE(channel->intent_req_result) >= 0 &&
+ READ_ONCE(channel->intent_received),
+ 10 * HZ);
+ if (!ret) {
+ dev_err(glink->dev, "intent request timed out\n");
+ ret = -ETIMEDOUT;
+ } else {
+ ret = READ_ONCE(channel->intent_req_result) ? 0 : -ECANCELED;
+ }
+
+unlock:
+ mutex_unlock(&channel->intent_req_lock);
+ return ret;
+}
+
+static int __qcom_glink_send(struct glink_channel *channel,
+ void *data, int len, bool wait)
+{
+ struct qcom_glink *glink = channel->glink;
+ struct glink_core_rx_intent *intent = NULL;
+ struct glink_core_rx_intent *tmp;
+ int iid = 0;
+ struct {
+ struct glink_msg msg;
+ __le32 chunk_size;
+ __le32 left_size;
+ } __packed req;
+ int ret;
+ unsigned long flags;
+ int chunk_size = len;
+ size_t offset = 0;
+
+ if (!glink->intentless) {
+ while (!intent) {
+ spin_lock_irqsave(&channel->intent_lock, flags);
+ idr_for_each_entry(&channel->riids, tmp, iid) {
+ if (tmp->size >= len && !tmp->in_use) {
+ if (!intent)
+ intent = tmp;
+ else if (intent->size > tmp->size)
+ intent = tmp;
+ if (intent->size == len)
+ break;
+ }
+ }
+ if (intent)
+ intent->in_use = true;
+ spin_unlock_irqrestore(&channel->intent_lock, flags);
+
+ /* We found an available intent */
+ if (intent)
+ break;
+
+ if (!wait)
+ return -EBUSY;
+
+ ret = qcom_glink_request_intent(glink, channel, len);
+ if (ret < 0)
+ return ret;
+ }
+
+ iid = intent->id;
+ }
+
+ while (offset < len) {
+ chunk_size = len - offset;
+ if (chunk_size > SZ_8K && wait)
+ chunk_size = SZ_8K;
+
+ req.msg.cmd = cpu_to_le16(offset == 0 ? GLINK_CMD_TX_DATA : GLINK_CMD_TX_DATA_CONT);
+ req.msg.param1 = cpu_to_le16(channel->lcid);
+ req.msg.param2 = cpu_to_le32(iid);
+ req.chunk_size = cpu_to_le32(chunk_size);
+ req.left_size = cpu_to_le32(len - offset - chunk_size);
+
+ ret = qcom_glink_tx(glink, &req, sizeof(req), data + offset, chunk_size, wait);
+ if (ret) {
+ /* Mark intent available if we failed */
+ if (intent)
+ intent->in_use = false;
+ return ret;
+ }
+
+ offset += chunk_size;
+ }
+
+ return 0;
+}
+
+static int qcom_glink_send(struct rpmsg_endpoint *ept, void *data, int len)
+{
+ struct glink_channel *channel = to_glink_channel(ept);
+
+ return __qcom_glink_send(channel, data, len, true);
+}
+
+static int qcom_glink_trysend(struct rpmsg_endpoint *ept, void *data, int len)
+{
+ struct glink_channel *channel = to_glink_channel(ept);
+
+ return __qcom_glink_send(channel, data, len, false);
+}
+
+static int qcom_glink_sendto(struct rpmsg_endpoint *ept, void *data, int len, u32 dst)
+{
+ struct glink_channel *channel = to_glink_channel(ept);
+
+ return __qcom_glink_send(channel, data, len, true);
+}
+
+static int qcom_glink_trysendto(struct rpmsg_endpoint *ept, void *data, int len, u32 dst)
+{
+ struct glink_channel *channel = to_glink_channel(ept);
+
+ return __qcom_glink_send(channel, data, len, false);
+}
+
+/*
+ * Finds the device_node for the glink child interested in this channel.
+ */
+static struct device_node *qcom_glink_match_channel(struct device_node *node,
+ const char *channel)
+{
+ struct device_node *child;
+ const char *name;
+ const char *key;
+ int ret;
+
+ for_each_available_child_of_node(node, child) {
+ key = "qcom,glink-channels";
+ ret = of_property_read_string(child, key, &name);
+ if (ret)
+ continue;
+
+ if (strcmp(name, channel) == 0)
+ return child;
+ }
+
+ return NULL;
+}
+
+static const struct rpmsg_device_ops glink_device_ops = {
+ .create_ept = qcom_glink_create_ept,
+ .announce_create = qcom_glink_announce_create,
+};
+
+static const struct rpmsg_endpoint_ops glink_endpoint_ops = {
+ .destroy_ept = qcom_glink_destroy_ept,
+ .send = qcom_glink_send,
+ .sendto = qcom_glink_sendto,
+ .trysend = qcom_glink_trysend,
+ .trysendto = qcom_glink_trysendto,
+ .set_flow_control = qcom_glink_set_flow_control,
+};
+
+static void qcom_glink_rpdev_release(struct device *dev)
+{
+ struct rpmsg_device *rpdev = to_rpmsg_device(dev);
+
+ kfree(rpdev->driver_override);
+ kfree(rpdev);
+}
+
+static int qcom_glink_rx_open(struct qcom_glink *glink, unsigned int rcid,
+ char *name)
+{
+ struct glink_channel *channel;
+ struct rpmsg_device *rpdev;
+ bool create_device = false;
+ struct device_node *node;
+ int lcid;
+ int ret;
+ unsigned long flags;
+
+ spin_lock_irqsave(&glink->idr_lock, flags);
+ idr_for_each_entry(&glink->lcids, channel, lcid) {
+ if (!strcmp(channel->name, name))
+ break;
+ }
+ spin_unlock_irqrestore(&glink->idr_lock, flags);
+
+ if (!channel) {
+ channel = qcom_glink_alloc_channel(glink, name);
+ if (IS_ERR(channel))
+ return PTR_ERR(channel);
+
+ /* The opening dance was initiated by the remote */
+ create_device = true;
+ }
+
+ spin_lock_irqsave(&glink->idr_lock, flags);
+ ret = idr_alloc(&glink->rcids, channel, rcid, rcid + 1, GFP_ATOMIC);
+ if (ret < 0) {
+ dev_err(glink->dev, "Unable to insert channel into rcid list\n");
+ spin_unlock_irqrestore(&glink->idr_lock, flags);
+ goto free_channel;
+ }
+ channel->rcid = ret;
+ spin_unlock_irqrestore(&glink->idr_lock, flags);
+
+ complete_all(&channel->open_req);
+
+ if (create_device) {
+ rpdev = kzalloc(sizeof(*rpdev), GFP_KERNEL);
+ if (!rpdev) {
+ ret = -ENOMEM;
+ goto rcid_remove;
+ }
+
+ rpdev->ept = &channel->ept;
+ strscpy_pad(rpdev->id.name, name, RPMSG_NAME_SIZE);
+ rpdev->src = RPMSG_ADDR_ANY;
+ rpdev->dst = RPMSG_ADDR_ANY;
+ rpdev->ops = &glink_device_ops;
+
+ node = qcom_glink_match_channel(glink->dev->of_node, name);
+ rpdev->dev.of_node = node;
+ rpdev->dev.parent = glink->dev;
+ rpdev->dev.release = qcom_glink_rpdev_release;
+
+ ret = rpmsg_register_device(rpdev);
+ if (ret)
+ goto rcid_remove;
+
+ channel->rpdev = rpdev;
+ }
+
+ return 0;
+
+rcid_remove:
+ spin_lock_irqsave(&glink->idr_lock, flags);
+ idr_remove(&glink->rcids, channel->rcid);
+ channel->rcid = 0;
+ spin_unlock_irqrestore(&glink->idr_lock, flags);
+free_channel:
+ /* Release the reference, iff we took it */
+ if (create_device)
+ kref_put(&channel->refcount, qcom_glink_channel_release);
+
+ return ret;
+}
+
+static void qcom_glink_rx_close(struct qcom_glink *glink, unsigned int rcid)
+{
+ struct rpmsg_channel_info chinfo;
+ struct glink_channel *channel;
+ unsigned long flags;
+
+ spin_lock_irqsave(&glink->idr_lock, flags);
+ channel = idr_find(&glink->rcids, rcid);
+ spin_unlock_irqrestore(&glink->idr_lock, flags);
+ if (WARN(!channel, "close request on unknown channel\n"))
+ return;
+
+ /* cancel pending rx_done work */
+ cancel_work_sync(&channel->intent_work);
+
+ if (channel->rpdev) {
+ strscpy_pad(chinfo.name, channel->name, sizeof(chinfo.name));
+ chinfo.src = RPMSG_ADDR_ANY;
+ chinfo.dst = RPMSG_ADDR_ANY;
+
+ rpmsg_unregister_device(glink->dev, &chinfo);
+ }
+ channel->rpdev = NULL;
+
+ qcom_glink_send_close_ack(glink, channel->rcid);
+
+ spin_lock_irqsave(&glink->idr_lock, flags);
+ idr_remove(&glink->rcids, channel->rcid);
+ channel->rcid = 0;
+ spin_unlock_irqrestore(&glink->idr_lock, flags);
+
+ kref_put(&channel->refcount, qcom_glink_channel_release);
+}
+
+static void qcom_glink_rx_close_ack(struct qcom_glink *glink, unsigned int lcid)
+{
+ struct rpmsg_channel_info chinfo;
+ struct glink_channel *channel;
+ unsigned long flags;
+
+ /* To wakeup any blocking writers */
+ wake_up_all(&glink->tx_avail_notify);
+
+ spin_lock_irqsave(&glink->idr_lock, flags);
+ channel = idr_find(&glink->lcids, lcid);
+ if (WARN(!channel, "close ack on unknown channel\n")) {
+ spin_unlock_irqrestore(&glink->idr_lock, flags);
+ return;
+ }
+
+ idr_remove(&glink->lcids, channel->lcid);
+ channel->lcid = 0;
+ spin_unlock_irqrestore(&glink->idr_lock, flags);
+
+ /* Decouple the potential rpdev from the channel */
+ if (channel->rpdev) {
+ strscpy(chinfo.name, channel->name, sizeof(chinfo.name));
+ chinfo.src = RPMSG_ADDR_ANY;
+ chinfo.dst = RPMSG_ADDR_ANY;
+
+ rpmsg_unregister_device(glink->dev, &chinfo);
+ }
+ channel->rpdev = NULL;
+
+ kref_put(&channel->refcount, qcom_glink_channel_release);
+}
+
+static void qcom_glink_work(struct work_struct *work)
+{
+ struct qcom_glink *glink = container_of(work, struct qcom_glink,
+ rx_work);
+ struct glink_defer_cmd *dcmd;
+ struct glink_msg *msg;
+ unsigned long flags;
+ unsigned int param1;
+ unsigned int param2;
+ unsigned int cmd;
+
+ for (;;) {
+ spin_lock_irqsave(&glink->rx_lock, flags);
+ if (list_empty(&glink->rx_queue)) {
+ spin_unlock_irqrestore(&glink->rx_lock, flags);
+ break;
+ }
+ dcmd = list_first_entry(&glink->rx_queue,
+ struct glink_defer_cmd, node);
+ list_del(&dcmd->node);
+ spin_unlock_irqrestore(&glink->rx_lock, flags);
+
+ msg = &dcmd->msg;
+ cmd = le16_to_cpu(msg->cmd);
+ param1 = le16_to_cpu(msg->param1);
+ param2 = le32_to_cpu(msg->param2);
+
+ switch (cmd) {
+ case GLINK_CMD_VERSION:
+ qcom_glink_receive_version(glink, param1, param2);
+ break;
+ case GLINK_CMD_VERSION_ACK:
+ qcom_glink_receive_version_ack(glink, param1, param2);
+ break;
+ case GLINK_CMD_OPEN:
+ qcom_glink_rx_open(glink, param1, msg->data);
+ break;
+ case GLINK_CMD_CLOSE:
+ qcom_glink_rx_close(glink, param1);
+ break;
+ case GLINK_CMD_CLOSE_ACK:
+ qcom_glink_rx_close_ack(glink, param1);
+ break;
+ case GLINK_CMD_RX_INTENT_REQ:
+ qcom_glink_handle_intent_req(glink, param1, param2);
+ break;
+ default:
+ WARN(1, "Unknown defer object %d\n", cmd);
+ break;
+ }
+
+ kfree(dcmd);
+ }
+}
+
+static void qcom_glink_cancel_rx_work(struct qcom_glink *glink)
+{
+ struct glink_defer_cmd *dcmd;
+ struct glink_defer_cmd *tmp;
+
+ /* cancel any pending deferred rx_work */
+ cancel_work_sync(&glink->rx_work);
+
+ list_for_each_entry_safe(dcmd, tmp, &glink->rx_queue, node)
+ kfree(dcmd);
+}
+
+static ssize_t rpmsg_name_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ int ret = 0;
+ const char *name;
+
+ ret = of_property_read_string(dev->of_node, "label", &name);
+ if (ret < 0)
+ name = dev->of_node->name;
+
+ return sysfs_emit(buf, "%s\n", name);
+}
+static DEVICE_ATTR_RO(rpmsg_name);
+
+static struct attribute *qcom_glink_attrs[] = {
+ &dev_attr_rpmsg_name.attr,
+ NULL
+};
+ATTRIBUTE_GROUPS(qcom_glink);
+
+static void qcom_glink_device_release(struct device *dev)
+{
+ struct rpmsg_device *rpdev = to_rpmsg_device(dev);
+ struct glink_channel *channel = to_glink_channel(rpdev->ept);
+
+ /* Release qcom_glink_alloc_channel() reference */
+ kref_put(&channel->refcount, qcom_glink_channel_release);
+ kfree(rpdev->driver_override);
+ kfree(rpdev);
+}
+
+static int qcom_glink_create_chrdev(struct qcom_glink *glink)
+{
+ struct rpmsg_device *rpdev;
+ struct glink_channel *channel;
+
+ rpdev = kzalloc(sizeof(*rpdev), GFP_KERNEL);
+ if (!rpdev)
+ return -ENOMEM;
+
+ channel = qcom_glink_alloc_channel(glink, "rpmsg_chrdev");
+ if (IS_ERR(channel)) {
+ kfree(rpdev);
+ return PTR_ERR(channel);
+ }
+ channel->rpdev = rpdev;
+
+ rpdev->ept = &channel->ept;
+ rpdev->ops = &glink_device_ops;
+ rpdev->dev.parent = glink->dev;
+ rpdev->dev.release = qcom_glink_device_release;
+
+ return rpmsg_ctrldev_register_device(rpdev);
+}
+
+struct qcom_glink *qcom_glink_native_probe(struct device *dev,
+ unsigned long features,
+ struct qcom_glink_pipe *rx,
+ struct qcom_glink_pipe *tx,
+ bool intentless)
+{
+ int ret;
+ struct qcom_glink *glink;
+
+ glink = devm_kzalloc(dev, sizeof(*glink), GFP_KERNEL);
+ if (!glink)
+ return ERR_PTR(-ENOMEM);
+
+ glink->dev = dev;
+ glink->tx_pipe = tx;
+ glink->rx_pipe = rx;
+
+ glink->features = features;
+ glink->intentless = intentless;
+
+ spin_lock_init(&glink->tx_lock);
+ spin_lock_init(&glink->rx_lock);
+ INIT_LIST_HEAD(&glink->rx_queue);
+ INIT_WORK(&glink->rx_work, qcom_glink_work);
+ init_waitqueue_head(&glink->tx_avail_notify);
+
+ spin_lock_init(&glink->idr_lock);
+ idr_init(&glink->lcids);
+ idr_init(&glink->rcids);
+
+ glink->dev->groups = qcom_glink_groups;
+
+ ret = device_add_groups(dev, qcom_glink_groups);
+ if (ret)
+ dev_err(dev, "failed to add groups\n");
+
+ ret = qcom_glink_send_version(glink);
+ if (ret)
+ return ERR_PTR(ret);
+
+ ret = qcom_glink_create_chrdev(glink);
+ if (ret)
+ dev_err(glink->dev, "failed to register chrdev\n");
+
+ return glink;
+}
+EXPORT_SYMBOL_GPL(qcom_glink_native_probe);
+
+static int qcom_glink_remove_device(struct device *dev, void *data)
+{
+ device_unregister(dev);
+
+ return 0;
+}
+
+void qcom_glink_native_remove(struct qcom_glink *glink)
+{
+ struct glink_channel *channel;
+ unsigned long flags;
+ int cid;
+ int ret;
+
+ qcom_glink_cancel_rx_work(glink);
+
+ /* Fail all attempts at sending messages */
+ spin_lock_irqsave(&glink->tx_lock, flags);
+ glink->abort_tx = true;
+ wake_up_all(&glink->tx_avail_notify);
+ spin_unlock_irqrestore(&glink->tx_lock, flags);
+
+ /* Abort any senders waiting for intent requests */
+ spin_lock_irqsave(&glink->idr_lock, flags);
+ idr_for_each_entry(&glink->lcids, channel, cid)
+ qcom_glink_intent_req_abort(channel);
+ spin_unlock_irqrestore(&glink->idr_lock, flags);
+
+ ret = device_for_each_child(glink->dev, NULL, qcom_glink_remove_device);
+ if (ret)
+ dev_warn(glink->dev, "Can't remove GLINK devices: %d\n", ret);
+
+ /* Release any defunct local channels, waiting for close-ack */
+ idr_for_each_entry(&glink->lcids, channel, cid)
+ kref_put(&channel->refcount, qcom_glink_channel_release);
+
+ /* Release any defunct local channels, waiting for close-req */
+ idr_for_each_entry(&glink->rcids, channel, cid)
+ kref_put(&channel->refcount, qcom_glink_channel_release);
+
+ idr_destroy(&glink->lcids);
+ idr_destroy(&glink->rcids);
+}
+EXPORT_SYMBOL_GPL(qcom_glink_native_remove);
+
+MODULE_DESCRIPTION("Qualcomm GLINK driver");
+MODULE_LICENSE("GPL v2");