From c92c3e382ebd2382b26a41e312a266a40c4fb05c Mon Sep 17 00:00:00 2001 From: Igor Skalkin Date: Tue, 3 Aug 2021 14:10:19 +0100 Subject: [PATCH] firmware: arm_scmi: Add method to override max message number The maximum number of simultaneously pending messages is a transport specific quantity that is usually described statically in struct scmi_desc. Some transports, though, can calculate such number only at run-time after some initial transport specific setup and probing is completed; moreover the resulting max message numbers could also be different between rx and tx channels. Add an optional get_max_msg() operation so that a transport can report more accurate max message numbers for each channel type. The value in scmi_desc.max_msg is still used as default when transport does not provide any get_max_msg() method. Link: https://lore.kernel.org/r/20210803131024.40280-11-cristian.marussi@arm.com Co-developed-by: Peter Hilber Co-developed-by: Cristian Marussi Signed-off-by: Igor Skalkin [ Peter: Adapted patch for submission to upstream. ] Signed-off-by: Peter Hilber [ Cristian: refactored how get_max_msg() is used to minimize core changes ] Signed-off-by: Cristian Marussi Signed-off-by: Sudeep Holla --- drivers/firmware/arm_scmi/common.h | 9 +++++-- drivers/firmware/arm_scmi/driver.c | 40 +++++++++++++++++++++++++++--- 2 files changed, 43 insertions(+), 6 deletions(-) diff --git a/drivers/firmware/arm_scmi/common.h b/drivers/firmware/arm_scmi/common.h index 204cde53a9a7..6320345865e8 100644 --- a/drivers/firmware/arm_scmi/common.h +++ b/drivers/firmware/arm_scmi/common.h @@ -351,6 +351,9 @@ struct scmi_chan_info { * @chan_available: Callback to check if channel is available or not * @chan_setup: Callback to allocate and setup a channel * @chan_free: Callback to free a channel + * @get_max_msg: Optional callback to provide max_msg dynamically + * Returns the maximum number of messages for the channel type + * (tx or rx) that can be pending simultaneously in the system * @send_message: Callback to send a message * @mark_txdone: Callback to mark tx as done * @fetch_response: Callback to fetch response @@ -363,6 +366,7 @@ struct scmi_transport_ops { int (*chan_setup)(struct scmi_chan_info *cinfo, struct device *dev, bool tx); int (*chan_free)(int id, void *p, void *data); + unsigned int (*get_max_msg)(struct scmi_chan_info *base_cinfo); int (*send_message)(struct scmi_chan_info *cinfo, struct scmi_xfer *xfer); void (*mark_txdone)(struct scmi_chan_info *cinfo, int ret); @@ -390,8 +394,9 @@ struct scmi_device *scmi_child_dev_find(struct device *parent, * de-initialization, so after SCMI core removal. * @ops: Pointer to the transport specific ops structure * @max_rx_timeout_ms: Timeout for communication with SoC (in Milliseconds) - * @max_msg: Maximum number of messages that can be pending - * simultaneously in the system + * @max_msg: Maximum number of messages for a channel type (tx or rx) that can + * be pending simultaneously in the system. May be overridden by the + * get_max_msg op. * @max_msg_size: Maximum size of data per message that can be handled. */ struct scmi_desc { diff --git a/drivers/firmware/arm_scmi/driver.c b/drivers/firmware/arm_scmi/driver.c index d20e6760b488..a907f3fe4c08 100644 --- a/drivers/firmware/arm_scmi/driver.c +++ b/drivers/firmware/arm_scmi/driver.c @@ -72,6 +72,7 @@ struct scmi_requested_dev { * Index of this bitmap table is also used for message * sequence identifier. * @xfer_lock: Protection for message allocation + * @max_msg: Maximum number of messages that can be pending * @free_xfers: A free list for available to use xfers. It is initialized with * a number of xfers equal to the maximum allowed in-flight * messages. @@ -81,6 +82,7 @@ struct scmi_requested_dev { struct scmi_xfers_info { unsigned long *xfer_alloc_table; spinlock_t xfer_lock; + int max_msg; struct hlist_head free_xfers; DECLARE_HASHTABLE(pending_xfers, SCMI_PENDING_XFERS_HT_ORDER_SZ); }; @@ -1373,10 +1375,10 @@ static int __scmi_xfer_info_init(struct scmi_info *sinfo, const struct scmi_desc *desc = sinfo->desc; /* Pre-allocated messages, no more than what hdr.seq can support */ - if (WARN_ON(!desc->max_msg || desc->max_msg > MSG_TOKEN_MAX)) { + if (WARN_ON(!info->max_msg || info->max_msg > MSG_TOKEN_MAX)) { dev_err(dev, "Invalid maximum messages %d, not in range [1 - %lu]\n", - desc->max_msg, MSG_TOKEN_MAX); + info->max_msg, MSG_TOKEN_MAX); return -EINVAL; } @@ -1394,7 +1396,7 @@ static int __scmi_xfer_info_init(struct scmi_info *sinfo, * attach all of them to the free list */ INIT_HLIST_HEAD(&info->free_xfers); - for (i = 0; i < desc->max_msg; i++) { + for (i = 0; i < info->max_msg; i++) { xfer = devm_kzalloc(dev, sizeof(*xfer), GFP_KERNEL); if (!xfer) return -ENOMEM; @@ -1417,10 +1419,40 @@ static int __scmi_xfer_info_init(struct scmi_info *sinfo, return 0; } +static int scmi_channels_max_msg_configure(struct scmi_info *sinfo) +{ + const struct scmi_desc *desc = sinfo->desc; + + if (!desc->ops->get_max_msg) { + sinfo->tx_minfo.max_msg = desc->max_msg; + sinfo->rx_minfo.max_msg = desc->max_msg; + } else { + struct scmi_chan_info *base_cinfo; + + base_cinfo = idr_find(&sinfo->tx_idr, SCMI_PROTOCOL_BASE); + if (!base_cinfo) + return -EINVAL; + sinfo->tx_minfo.max_msg = desc->ops->get_max_msg(base_cinfo); + + /* RX channel is optional so can be skipped */ + base_cinfo = idr_find(&sinfo->rx_idr, SCMI_PROTOCOL_BASE); + if (base_cinfo) + sinfo->rx_minfo.max_msg = + desc->ops->get_max_msg(base_cinfo); + } + + return 0; +} + static int scmi_xfer_info_init(struct scmi_info *sinfo) { - int ret = __scmi_xfer_info_init(sinfo, &sinfo->tx_minfo); + int ret; + ret = scmi_channels_max_msg_configure(sinfo); + if (ret) + return ret; + + ret = __scmi_xfer_info_init(sinfo, &sinfo->tx_minfo); if (!ret && idr_find(&sinfo->rx_idr, SCMI_PROTOCOL_BASE)) ret = __scmi_xfer_info_init(sinfo, &sinfo->rx_minfo);