};
/**
- * struct scmi_chan_info - Structure representing a SCMI channel informfation
+ * struct scmi_chan_info - Structure representing a SCMI channel information
*
* @cl: Mailbox Client
* @chan: Transmit/Receive mailbox channel
* @version: SCMI revision information containing protocol version,
* implementation version and (sub-)vendor identification.
* @minfo: Message info
- * @tx_idr: IDR object to map protocol id to channel info pointer
+ * @tx_idr: IDR object to map protocol id to Tx channel info pointer
* @protocols_imp: List of protocols implemented, currently maximum of
* MAX_PROTOCOLS_IMP elements allocated by the base protocol
* @node: List head
static inline void scmi_dump_header_dbg(struct device *dev,
struct scmi_msg_hdr *hdr)
{
- dev_dbg(dev, "Command ID: %x Sequence ID: %x Protocol: %x\n",
+ dev_dbg(dev, "Message ID: %x Sequence ID: %x Protocol: %x\n",
hdr->id, hdr->seq, hdr->protocol_id);
}
struct scmi_shared_mem __iomem *mem)
{
xfer->hdr.status = ioread32(mem->msg_payload);
- /* Skip the length of header and statues in payload area i.e 8 bytes*/
+ /* Skip the length of header and status in payload area i.e 8 bytes */
xfer->rx.len = min_t(size_t, xfer->rx.len, ioread32(&mem->length) - 8);
/* Take a copy to the rx buffer.. */
memcpy_fromio(xfer->rx.buf, mem->msg_payload + 4, xfer->rx.len);
}
-/**
- * scmi_rx_callback() - mailbox client callback for receive messages
- *
- * @cl: client pointer
- * @m: mailbox message
- *
- * Processes one received message to appropriate transfer information and
- * signals completion of the transfer.
- *
- * NOTE: This function will be invoked in IRQ context, hence should be
- * as optimal as possible.
- */
-static void scmi_rx_callback(struct mbox_client *cl, void *m)
-{
- u16 xfer_id;
- struct scmi_xfer *xfer;
- struct scmi_chan_info *cinfo = client_to_scmi_chan_info(cl);
- struct device *dev = cinfo->dev;
- struct scmi_info *info = handle_to_scmi_info(cinfo->handle);
- struct scmi_xfers_info *minfo = &info->minfo;
- struct scmi_shared_mem __iomem *mem = cinfo->payload;
-
- xfer_id = MSG_XTRACT_TOKEN(ioread32(&mem->msg_header));
-
- /* Are we even expecting this? */
- if (!test_bit(xfer_id, minfo->xfer_alloc_table)) {
- dev_err(dev, "message for %d is not expected!\n", xfer_id);
- return;
- }
-
- xfer = &minfo->xfer_block[xfer_id];
-
- scmi_dump_header_dbg(dev, &xfer->hdr);
- /* Is the message of valid length? */
- if (xfer->rx.len > info->desc->max_msg_size) {
- dev_err(dev, "unable to handle %zu xfer(max %d)\n",
- xfer->rx.len, info->desc->max_msg_size);
- return;
- }
-
- scmi_fetch_response(xfer, mem);
- complete(&xfer->done);
-}
-
/**
* pack_scmi_header() - packs and returns 32-bit header
*
* @hdr: pointer to header containing all the information on message id,
* protocol id and sequence id.
*
- * Return: 32-bit packed command header to be sent to the platform.
+ * Return: 32-bit packed message header to be sent to the platform.
*/
static inline u32 pack_scmi_header(struct scmi_msg_hdr *hdr)
{
struct scmi_chan_info *cinfo = client_to_scmi_chan_info(cl);
struct scmi_shared_mem __iomem *mem = cinfo->payload;
+ /*
+ * Ideally channel must be free by now unless OS timeout last
+ * request and platform continued to process the same, wait
+ * until it releases the shared memory, otherwise we may endup
+ * overwriting its response with new message payload or vice-versa
+ */
+ spin_until_cond(ioread32(&mem->channel_status) &
+ SCMI_SHMEM_CHAN_STAT_CHANNEL_FREE);
/* Mark channel busy + clear error */
iowrite32(0x0, &mem->channel_status);
iowrite32(t->hdr.poll_completion ? 0 : SCMI_SHMEM_FLAG_INTR_ENABLED,
*
* @handle: Pointer to SCMI entity handle
*
- * Helper function which is used by various command functions that are
+ * Helper function which is used by various message functions that are
* exposed to clients of this driver for allocating a message traffic event.
*
* This function can sleep depending on pending requests already in the system
spin_unlock_irqrestore(&minfo->xfer_lock, flags);
}
+/**
+ * scmi_rx_callback() - mailbox client callback for receive messages
+ *
+ * @cl: client pointer
+ * @m: mailbox message
+ *
+ * Processes one received message to appropriate transfer information and
+ * signals completion of the transfer.
+ *
+ * NOTE: This function will be invoked in IRQ context, hence should be
+ * as optimal as possible.
+ */
+static void scmi_rx_callback(struct mbox_client *cl, void *m)
+{
+ u16 xfer_id;
+ struct scmi_xfer *xfer;
+ struct scmi_chan_info *cinfo = client_to_scmi_chan_info(cl);
+ struct device *dev = cinfo->dev;
+ struct scmi_info *info = handle_to_scmi_info(cinfo->handle);
+ struct scmi_xfers_info *minfo = &info->minfo;
+ struct scmi_shared_mem __iomem *mem = cinfo->payload;
+
+ xfer_id = MSG_XTRACT_TOKEN(ioread32(&mem->msg_header));
+
+ /* Are we even expecting this? */
+ if (!test_bit(xfer_id, minfo->xfer_alloc_table)) {
+ dev_err(dev, "message for %d is not expected!\n", xfer_id);
+ return;
+ }
+
+ xfer = &minfo->xfer_block[xfer_id];
+
+ scmi_dump_header_dbg(dev, &xfer->hdr);
+
+ scmi_fetch_response(xfer, mem);
+ complete(&xfer->done);
+}
+
static bool
scmi_xfer_poll_done(const struct scmi_chan_info *cinfo, struct scmi_xfer *xfer)
{
return 0;
}
-static const struct scmi_desc scmi_generic_desc = {
- .max_rx_timeout_ms = 30, /* We may increase this if required */
- .max_msg = 20, /* Limited by MBOX_TX_QUEUE_LEN */
- .max_msg_size = 128,
-};
-
-/* Each compatible listed below must have descriptor associated with it */
-static const struct of_device_id scmi_of_match[] = {
- { .compatible = "arm,scmi", .data = &scmi_generic_desc },
- { /* Sentinel */ },
-};
-
-MODULE_DEVICE_TABLE(of, scmi_of_match);
-
static int scmi_xfer_info_init(struct scmi_info *sinfo)
{
int i;
return 0;
}
-static int scmi_mailbox_check(struct device_node *np)
+static int scmi_mailbox_check(struct device_node *np, int idx)
{
- return of_parse_phandle_with_args(np, "mboxes", "#mbox-cells", 0, NULL);
+ return of_parse_phandle_with_args(np, "mboxes", "#mbox-cells",
+ idx, NULL);
}
-static int scmi_mbox_free_channel(int id, void *p, void *data)
-{
- struct scmi_chan_info *cinfo = p;
- struct idr *idr = data;
-
- if (!IS_ERR_OR_NULL(cinfo->chan)) {
- mbox_free_channel(cinfo->chan);
- cinfo->chan = NULL;
- }
-
- idr_remove(idr, id);
-
- return 0;
-}
-
-static int scmi_remove(struct platform_device *pdev)
+static int scmi_mbox_chan_setup(struct scmi_info *info, struct device *dev,
+ int prot_id, bool tx)
{
- int ret = 0;
- struct scmi_info *info = platform_get_drvdata(pdev);
- struct idr *idr = &info->tx_idr;
-
- mutex_lock(&scmi_list_mutex);
- if (info->users)
- ret = -EBUSY;
- else
- list_del(&info->node);
- mutex_unlock(&scmi_list_mutex);
-
- if (ret)
- return ret;
-
- /* Safe to free channels since no more users */
- ret = idr_for_each(idr, scmi_mbox_free_channel, idr);
- idr_destroy(&info->tx_idr);
-
- return ret;
-}
-
-static inline int
-scmi_mbox_chan_setup(struct scmi_info *info, struct device *dev, int prot_id)
-{
- int ret;
+ int ret, idx;
struct resource res;
resource_size_t size;
struct device_node *shmem, *np = dev->of_node;
struct scmi_chan_info *cinfo;
struct mbox_client *cl;
+ const char *desc = tx ? "Tx" : "Rx";
- if (scmi_mailbox_check(np)) {
+ /* Transmit channel is first entry i.e. index 0 */
+ idx = tx ? 0 : 1;
+
+ if (scmi_mailbox_check(np, idx)) {
cinfo = idr_find(&info->tx_idr, SCMI_PROTOCOL_BASE);
goto idr_alloc;
}
cl = &cinfo->cl;
cl->dev = dev;
cl->rx_callback = scmi_rx_callback;
- cl->tx_prepare = scmi_tx_prepare;
+ cl->tx_prepare = tx ? scmi_tx_prepare : NULL;
cl->tx_block = false;
- cl->knows_txdone = true;
+ cl->knows_txdone = tx;
- shmem = of_parse_phandle(np, "shmem", 0);
+ shmem = of_parse_phandle(np, "shmem", idx);
ret = of_address_to_resource(shmem, 0, &res);
of_node_put(shmem);
if (ret) {
- dev_err(dev, "failed to get SCMI Tx payload mem resource\n");
+ dev_err(dev, "failed to get SCMI %s payload memory\n", desc);
return ret;
}
size = resource_size(&res);
cinfo->payload = devm_ioremap(info->dev, res.start, size);
if (!cinfo->payload) {
- dev_err(dev, "failed to ioremap SCMI Tx payload\n");
+ dev_err(dev, "failed to ioremap SCMI %s payload\n", desc);
return -EADDRNOTAVAIL;
}
- /* Transmit channel is first entry i.e. index 0 */
- cinfo->chan = mbox_request_channel(cl, 0);
+ cinfo->chan = mbox_request_channel(cl, idx);
if (IS_ERR(cinfo->chan)) {
ret = PTR_ERR(cinfo->chan);
if (ret != -EPROBE_DEFER)
- dev_err(dev, "failed to request SCMI Tx mailbox\n");
+ dev_err(dev, "failed to request SCMI %s mailbox\n",
+ desc);
return ret;
}
return;
}
- if (scmi_mbox_chan_setup(info, &sdev->dev, prot_id)) {
+ if (scmi_mbox_chan_setup(info, &sdev->dev, prot_id, true)) {
dev_err(&sdev->dev, "failed to setup transport\n");
scmi_device_destroy(sdev);
return;
struct device_node *child, *np = dev->of_node;
/* Only mailbox method supported, check for the presence of one */
- if (scmi_mailbox_check(np)) {
+ if (scmi_mailbox_check(np, 0)) {
dev_err(dev, "no mailbox found in %pOF\n", np);
return -EINVAL;
}
handle->dev = info->dev;
handle->version = &info->version;
- ret = scmi_mbox_chan_setup(info, dev, SCMI_PROTOCOL_BASE);
+ ret = scmi_mbox_chan_setup(info, dev, SCMI_PROTOCOL_BASE, true);
if (ret)
return ret;
return 0;
}
+static int scmi_mbox_free_channel(int id, void *p, void *data)
+{
+ struct scmi_chan_info *cinfo = p;
+ struct idr *idr = data;
+
+ if (!IS_ERR_OR_NULL(cinfo->chan)) {
+ mbox_free_channel(cinfo->chan);
+ cinfo->chan = NULL;
+ }
+
+ idr_remove(idr, id);
+
+ return 0;
+}
+
+static int scmi_remove(struct platform_device *pdev)
+{
+ int ret = 0;
+ struct scmi_info *info = platform_get_drvdata(pdev);
+ struct idr *idr = &info->tx_idr;
+
+ mutex_lock(&scmi_list_mutex);
+ if (info->users)
+ ret = -EBUSY;
+ else
+ list_del(&info->node);
+ mutex_unlock(&scmi_list_mutex);
+
+ if (ret)
+ return ret;
+
+ /* Safe to free channels since no more users */
+ ret = idr_for_each(idr, scmi_mbox_free_channel, idr);
+ idr_destroy(&info->tx_idr);
+
+ return ret;
+}
+
+static const struct scmi_desc scmi_generic_desc = {
+ .max_rx_timeout_ms = 30, /* We may increase this if required */
+ .max_msg = 20, /* Limited by MBOX_TX_QUEUE_LEN */
+ .max_msg_size = 128,
+};
+
+/* Each compatible listed below must have descriptor associated with it */
+static const struct of_device_id scmi_of_match[] = {
+ { .compatible = "arm,scmi", .data = &scmi_generic_desc },
+ { /* Sentinel */ },
+};
+
+MODULE_DEVICE_TABLE(of, scmi_of_match);
+
static struct platform_driver scmi_driver = {
.driver = {
.name = "arm-scmi",
projects / linux-block.git / blobdiff