diff options
Diffstat (limited to 'drivers/firmware/arm_scmi/driver.c')
| -rw-r--r-- | drivers/firmware/arm_scmi/driver.c | 366 |
1 files changed, 233 insertions, 133 deletions
diff --git a/drivers/firmware/arm_scmi/driver.c b/drivers/firmware/arm_scmi/driver.c index b5bc4c7a8fab..3eb0382491ce 100644 --- a/drivers/firmware/arm_scmi/driver.c +++ b/drivers/firmware/arm_scmi/driver.c @@ -30,8 +30,14 @@ #include "common.h" #define MSG_ID_MASK GENMASK(7, 0) +#define MSG_XTRACT_ID(hdr) FIELD_GET(MSG_ID_MASK, (hdr)) #define MSG_TYPE_MASK GENMASK(9, 8) +#define MSG_XTRACT_TYPE(hdr) FIELD_GET(MSG_TYPE_MASK, (hdr)) +#define MSG_TYPE_COMMAND 0 +#define MSG_TYPE_DELAYED_RESP 2 +#define MSG_TYPE_NOTIFICATION 3 #define MSG_PROTOCOL_ID_MASK GENMASK(17, 10) +#define MSG_XTRACT_PROT_ID(hdr) FIELD_GET(MSG_PROTOCOL_ID_MASK, (hdr)) #define MSG_TOKEN_ID_MASK GENMASK(27, 18) #define MSG_XTRACT_TOKEN(hdr) FIELD_GET(MSG_TOKEN_ID_MASK, (hdr)) #define MSG_TOKEN_MAX (MSG_XTRACT_TOKEN(MSG_TOKEN_ID_MASK) + 1) @@ -86,7 +92,7 @@ struct scmi_desc { }; /** - * 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 @@ -111,8 +117,9 @@ struct scmi_chan_info { * @handle: Instance of SCMI handle to send to clients * @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_minfo: Universal Transmit Message management info + * @tx_idr: IDR object to map protocol id to Tx channel info pointer + * @rx_idr: IDR object to map protocol id to Rx channel info pointer * @protocols_imp: List of protocols implemented, currently maximum of * MAX_PROTOCOLS_IMP elements allocated by the base protocol * @node: List head @@ -123,8 +130,9 @@ struct scmi_info { const struct scmi_desc *desc; struct scmi_revision_info version; struct scmi_handle handle; - struct scmi_xfers_info minfo; + struct scmi_xfers_info tx_minfo; struct idr tx_idr; + struct idr rx_idr; u8 *protocols_imp; struct list_head node; int users; @@ -182,7 +190,7 @@ static inline int scmi_to_linux_errno(int errno) 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); } @@ -190,7 +198,7 @@ static void scmi_fetch_response(struct scmi_xfer *xfer, 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.. */ @@ -198,56 +206,12 @@ static void scmi_fetch_response(struct scmi_xfer *xfer, } /** - * 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) { @@ -257,6 +221,18 @@ static inline u32 pack_scmi_header(struct scmi_msg_hdr *hdr) } /** + * unpack_scmi_header() - unpacks and records message and protocol id + * + * @msg_hdr: 32-bit packed message header sent from the platform + * @hdr: pointer to header to fetch message and protocol id. + */ +static inline void unpack_scmi_header(u32 msg_hdr, struct scmi_msg_hdr *hdr) +{ + hdr->id = MSG_XTRACT_ID(msg_hdr); + hdr->protocol_id = MSG_XTRACT_PROT_ID(msg_hdr); +} + +/** * scmi_tx_prepare() - mailbox client callback to prepare for the transfer * * @cl: client pointer @@ -271,6 +247,14 @@ static void scmi_tx_prepare(struct mbox_client *cl, void *m) 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, @@ -285,8 +269,9 @@ static void scmi_tx_prepare(struct mbox_client *cl, void *m) * scmi_xfer_get() - Allocate one message * * @handle: Pointer to SCMI entity handle + * @minfo: Pointer to Tx/Rx Message management info based on channel type * - * 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 @@ -295,13 +280,13 @@ static void scmi_tx_prepare(struct mbox_client *cl, void *m) * * Return: 0 if all went fine, else corresponding error. */ -static struct scmi_xfer *scmi_xfer_get(const struct scmi_handle *handle) +static struct scmi_xfer *scmi_xfer_get(const struct scmi_handle *handle, + struct scmi_xfers_info *minfo) { u16 xfer_id; struct scmi_xfer *xfer; unsigned long flags, bit_pos; struct scmi_info *info = handle_to_scmi_info(handle); - struct scmi_xfers_info *minfo = &info->minfo; /* Keep the locked section as small as possible */ spin_lock_irqsave(&minfo->xfer_lock, flags); @@ -324,18 +309,17 @@ static struct scmi_xfer *scmi_xfer_get(const struct scmi_handle *handle) } /** - * scmi_xfer_put() - Release a message + * __scmi_xfer_put() - Release a message * - * @handle: Pointer to SCMI entity handle + * @minfo: Pointer to Tx/Rx Message management info based on channel type * @xfer: message that was reserved by scmi_xfer_get * * This holds a spinlock to maintain integrity of internal data structures. */ -void scmi_xfer_put(const struct scmi_handle *handle, struct scmi_xfer *xfer) +static void +__scmi_xfer_put(struct scmi_xfers_info *minfo, struct scmi_xfer *xfer) { unsigned long flags; - struct scmi_info *info = handle_to_scmi_info(handle); - struct scmi_xfers_info *minfo = &info->minfo; /* * Keep the locked section as small as possible @@ -347,6 +331,68 @@ void scmi_xfer_put(const struct scmi_handle *handle, struct scmi_xfer *xfer) 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) +{ + u8 msg_type; + u32 msg_hdr; + 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->tx_minfo; + struct scmi_shared_mem __iomem *mem = cinfo->payload; + + msg_hdr = ioread32(&mem->msg_header); + msg_type = MSG_XTRACT_TYPE(msg_hdr); + xfer_id = MSG_XTRACT_TOKEN(msg_hdr); + + if (msg_type == MSG_TYPE_NOTIFICATION) + return; /* Notifications not yet supported */ + + /* 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); + + if (msg_type == MSG_TYPE_DELAYED_RESP) + complete(xfer->async_done); + else + complete(&xfer->done); +} + +/** + * scmi_xfer_put() - Release a transmit message + * + * @handle: Pointer to SCMI entity handle + * @xfer: message that was reserved by scmi_xfer_get + */ +void scmi_xfer_put(const struct scmi_handle *handle, struct scmi_xfer *xfer) +{ + struct scmi_info *info = handle_to_scmi_info(handle); + + __scmi_xfer_put(&info->tx_minfo, xfer); +} + static bool scmi_xfer_poll_done(const struct scmi_chan_info *cinfo, struct scmi_xfer *xfer) { @@ -435,8 +481,36 @@ int scmi_do_xfer(const struct scmi_handle *handle, struct scmi_xfer *xfer) return ret; } +#define SCMI_MAX_RESPONSE_TIMEOUT (2 * MSEC_PER_SEC) + +/** + * scmi_do_xfer_with_response() - Do one transfer and wait until the delayed + * response is received + * + * @handle: Pointer to SCMI entity handle + * @xfer: Transfer to initiate and wait for response + * + * Return: -ETIMEDOUT in case of no delayed response, if transmit error, + * return corresponding error, else if all goes well, return 0. + */ +int scmi_do_xfer_with_response(const struct scmi_handle *handle, + struct scmi_xfer *xfer) +{ + int ret, timeout = msecs_to_jiffies(SCMI_MAX_RESPONSE_TIMEOUT); + DECLARE_COMPLETION_ONSTACK(async_response); + + xfer->async_done = &async_response; + + ret = scmi_do_xfer(handle, xfer); + if (!ret && !wait_for_completion_timeout(xfer->async_done, timeout)) + ret = -ETIMEDOUT; + + xfer->async_done = NULL; + return ret; +} + /** - * scmi_xfer_get_init() - Allocate and initialise one message + * scmi_xfer_get_init() - Allocate and initialise one message for transmit * * @handle: Pointer to SCMI entity handle * @msg_id: Message identifier @@ -457,6 +531,7 @@ int scmi_xfer_get_init(const struct scmi_handle *handle, u8 msg_id, u8 prot_id, int ret; struct scmi_xfer *xfer; struct scmi_info *info = handle_to_scmi_info(handle); + struct scmi_xfers_info *minfo = &info->tx_minfo; struct device *dev = info->dev; /* Ensure we have sane transfer sizes */ @@ -464,7 +539,7 @@ int scmi_xfer_get_init(const struct scmi_handle *handle, u8 msg_id, u8 prot_id, tx_size > info->desc->max_msg_size) return -ERANGE; - xfer = scmi_xfer_get(handle); + xfer = scmi_xfer_get(handle, minfo); if (IS_ERR(xfer)) { ret = PTR_ERR(xfer); dev_err(dev, "failed to get free message slot(%d)\n", ret); @@ -597,27 +672,13 @@ int scmi_handle_put(const struct scmi_handle *handle) 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; struct scmi_xfer *xfer; struct device *dev = sinfo->dev; const struct scmi_desc *desc = sinfo->desc; - struct scmi_xfers_info *info = &sinfo->minfo; + struct scmi_xfers_info *info = &sinfo->tx_minfo; /* Pre-allocated messages, no more than what hdr.seq can support */ if (WARN_ON(desc->max_msg >= MSG_TOKEN_MAX)) { @@ -652,61 +713,32 @@ static int scmi_xfer_info_init(struct scmi_info *sinfo) 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) +static int scmi_mbox_chan_setup(struct scmi_info *info, struct device *dev, + int prot_id, bool tx) { - 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 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; + struct idr *idr; + const char *desc = tx ? "Tx" : "Rx"; - if (scmi_mailbox_check(np)) { - cinfo = idr_find(&info->tx_idr, SCMI_PROTOCOL_BASE); + /* Transmit channel is first entry i.e. index 0 */ + idx = tx ? 0 : 1; + idr = tx ? &info->tx_idr : &info->rx_idr; + + if (scmi_mailbox_check(np, idx)) { + cinfo = idr_find(idr, SCMI_PROTOCOL_BASE); + if (unlikely(!cinfo)) /* Possible only if platform has no Rx */ + return -EINVAL; goto idr_alloc; } @@ -719,36 +751,36 @@ scmi_mbox_chan_setup(struct scmi_info *info, struct device *dev, int prot_id) 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; } idr_alloc: - ret = idr_alloc(&info->tx_idr, cinfo, prot_id, prot_id + 1, GFP_KERNEL); + ret = idr_alloc(idr, cinfo, prot_id, prot_id + 1, GFP_KERNEL); if (ret != prot_id) { dev_err(dev, "unable to allocate SCMI idr slot err %d\n", ret); return ret; @@ -758,6 +790,17 @@ idr_alloc: return 0; } +static inline int +scmi_mbox_txrx_setup(struct scmi_info *info, struct device *dev, int prot_id) +{ + int ret = scmi_mbox_chan_setup(info, dev, prot_id, true); + + if (!ret) /* Rx is optional, hence no error check */ + scmi_mbox_chan_setup(info, dev, prot_id, false); + + return ret; +} + static inline void scmi_create_protocol_device(struct device_node *np, struct scmi_info *info, int prot_id) @@ -771,7 +814,7 @@ scmi_create_protocol_device(struct device_node *np, struct scmi_info *info, return; } - if (scmi_mbox_chan_setup(info, &sdev->dev, prot_id)) { + if (scmi_mbox_txrx_setup(info, &sdev->dev, prot_id)) { dev_err(&sdev->dev, "failed to setup transport\n"); scmi_device_destroy(sdev); return; @@ -791,7 +834,7 @@ static int scmi_probe(struct platform_device *pdev) 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; } @@ -814,12 +857,13 @@ static int scmi_probe(struct platform_device *pdev) platform_set_drvdata(pdev, info); idr_init(&info->tx_idr); + idr_init(&info->rx_idr); handle = &info->handle; handle->dev = info->dev; handle->version = &info->version; - ret = scmi_mbox_chan_setup(info, dev, SCMI_PROTOCOL_BASE); + ret = scmi_mbox_txrx_setup(info, dev, SCMI_PROTOCOL_BASE); if (ret) return ret; @@ -854,6 +898,62 @@ static int scmi_probe(struct platform_device *pdev) 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); + + idr = &info->rx_idr; + ret = idr_for_each(idr, scmi_mbox_free_channel, idr); + idr_destroy(&info->rx_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", |