From 3095a3e25d8f7d2cfa783aff51b3126c4c728109 Mon Sep 17 00:00:00 2001 From: Cristian Marussi Date: Wed, 18 Jan 2023 12:14:14 +0000 Subject: [PATCH] firmware: arm_scmi: Add xfer helpers to provide raw access Add a few SCMI helpers useful to implement SCMI raw access support. Signed-off-by: Cristian Marussi Tested-by: Florian Fainelli Tested-by: Vincent Guittot Link: https://lore.kernel.org/r/20230118121426.492864-6-cristian.marussi@arm.com Signed-off-by: Sudeep Holla --- drivers/firmware/arm_scmi/common.h | 12 +++ drivers/firmware/arm_scmi/driver.c | 147 +++++++++++++++++++++++++++++++++++++ 2 files changed, 159 insertions(+) diff --git a/drivers/firmware/arm_scmi/common.h b/drivers/firmware/arm_scmi/common.h index f785f0f..e9aa1cf 100644 --- a/drivers/firmware/arm_scmi/common.h +++ b/drivers/firmware/arm_scmi/common.h @@ -229,6 +229,18 @@ static inline bool is_polling_enabled(struct scmi_chan_info *cinfo, is_transport_polling_capable(desc); } +void scmi_xfer_raw_put(const struct scmi_handle *handle, + struct scmi_xfer *xfer); +struct scmi_xfer *scmi_xfer_raw_get(const struct scmi_handle *handle); +struct scmi_chan_info * +scmi_xfer_raw_channel_get(const struct scmi_handle *handle, u8 protocol_id); + +int scmi_xfer_raw_inflight_register(const struct scmi_handle *handle, + struct scmi_xfer *xfer); + +int scmi_xfer_raw_wait_for_message_response(struct scmi_chan_info *cinfo, + struct scmi_xfer *xfer, + unsigned int timeout_ms); #ifdef CONFIG_ARM_SCMI_TRANSPORT_MAILBOX extern const struct scmi_desc scmi_mailbox_desc; #endif diff --git a/drivers/firmware/arm_scmi/driver.c b/drivers/firmware/arm_scmi/driver.c index ce204a7..6707269 100644 --- a/drivers/firmware/arm_scmi/driver.c +++ b/drivers/firmware/arm_scmi/driver.c @@ -451,6 +451,53 @@ scmi_xfer_inflight_register_unlocked(struct scmi_xfer *xfer, } /** + * scmi_xfer_inflight_register - Try to register an xfer as in-flight + * + * @xfer: The xfer to register + * @minfo: Pointer to Tx/Rx Message management info based on channel type + * + * Note that this helper does NOT assume anything about the sequence number + * that was baked into the provided xfer, so it checks at first if it can + * be mapped to a free slot and fails with an error if another xfer with the + * same sequence number is currently still registered as in-flight. + * + * Return: 0 on Success or -EBUSY if sequence number embedded in the xfer + * could not rbe mapped to a free slot in the xfer_alloc_table. + */ +static int scmi_xfer_inflight_register(struct scmi_xfer *xfer, + struct scmi_xfers_info *minfo) +{ + int ret = 0; + unsigned long flags; + + spin_lock_irqsave(&minfo->xfer_lock, flags); + if (!test_bit(xfer->hdr.seq, minfo->xfer_alloc_table)) + scmi_xfer_inflight_register_unlocked(xfer, minfo); + else + ret = -EBUSY; + spin_unlock_irqrestore(&minfo->xfer_lock, flags); + + return ret; +} + +/** + * scmi_xfer_raw_inflight_register - An helper to register the given xfer as in + * flight on the TX channel, if possible. + * + * @handle: Pointer to SCMI entity handle + * @xfer: The xfer to register + * + * Return: 0 on Success, error otherwise + */ +int scmi_xfer_raw_inflight_register(const struct scmi_handle *handle, + struct scmi_xfer *xfer) +{ + struct scmi_info *info = handle_to_scmi_info(handle); + + return scmi_xfer_inflight_register(xfer, &info->tx_minfo); +} + +/** * scmi_xfer_pending_set - Pick a proper sequence number and mark the xfer * as pending in-flight * @@ -526,6 +573,63 @@ static struct scmi_xfer *scmi_xfer_get(const struct scmi_handle *handle, } /** + * scmi_xfer_raw_get - Helper to get a bare free xfer from the TX channel + * + * @handle: Pointer to SCMI entity handle + * + * Note that xfer is taken from the TX channel structures. + * + * Return: A valid xfer on Success, or an error-pointer otherwise + */ +struct scmi_xfer *scmi_xfer_raw_get(const struct scmi_handle *handle) +{ + struct scmi_xfer *xfer; + struct scmi_info *info = handle_to_scmi_info(handle); + + xfer = scmi_xfer_get(handle, &info->tx_minfo); + if (!IS_ERR(xfer)) + xfer->flags |= SCMI_XFER_FLAG_IS_RAW; + + return xfer; +} + +/** + * scmi_xfer_raw_channel_get - Helper to get a reference to the proper channel + * to use for a specific protocol_id Raw transaction. + * + * @handle: Pointer to SCMI entity handle + * @protocol_id: Identifier of the protocol + * + * Note that in a regular SCMI stack, usually, a protocol has to be defined in + * the DT to have an associated channel and be usable; but in Raw mode any + * protocol in range is allowed, re-using the Base channel, so as to enable + * fuzzing on any protocol without the need of a fully compiled DT. + * + * Return: A reference to the channel to use, or an ERR_PTR + */ +struct scmi_chan_info * +scmi_xfer_raw_channel_get(const struct scmi_handle *handle, u8 protocol_id) +{ + struct scmi_chan_info *cinfo; + struct scmi_info *info = handle_to_scmi_info(handle); + + cinfo = idr_find(&info->tx_idr, protocol_id); + if (!cinfo) { + if (protocol_id == SCMI_PROTOCOL_BASE) + return ERR_PTR(-EINVAL); + /* Use Base channel for protocols not defined for DT */ + cinfo = idr_find(&info->tx_idr, SCMI_PROTOCOL_BASE); + if (!cinfo) + return ERR_PTR(-EINVAL); + dev_warn_once(handle->dev, + "Using Base channel for protocol 0x%X\n", + protocol_id); + } + + return cinfo; +} + +/** * __scmi_xfer_put() - Release a message * * @minfo: Pointer to Tx/Rx Message management info based on channel type @@ -554,6 +658,23 @@ __scmi_xfer_put(struct scmi_xfers_info *minfo, struct scmi_xfer *xfer) } /** + * scmi_xfer_raw_put - Release an xfer that was taken by @scmi_xfer_raw_get + * + * @handle: Pointer to SCMI entity handle + * @xfer: A reference to the xfer to put + * + * Note that as with other xfer_put() handlers the xfer is really effectively + * released only if there are no more users on the system. + */ +void scmi_xfer_raw_put(const struct scmi_handle *handle, struct scmi_xfer *xfer) +{ + struct scmi_info *info = handle_to_scmi_info(handle); + + xfer->flags &= ~SCMI_XFER_FLAG_IS_RAW; + return __scmi_xfer_put(&info->tx_minfo, xfer); +} + +/** * scmi_xfer_lookup_unlocked - Helper to lookup an xfer_id * * @minfo: Pointer to Tx/Rx Message management info based on channel type @@ -980,6 +1101,32 @@ static int scmi_wait_for_message_response(struct scmi_chan_info *cinfo, } /** + * scmi_xfer_raw_wait_for_message_response - An helper to wait for a message + * reply to an xfer raw request on a specific channel for the required timeout. + * + * @cinfo: SCMI channel info + * @xfer: Reference to the transfer being waited for. + * @timeout_ms: The maximum timeout in milliseconds + * + * Return: 0 on Success, error otherwise. + */ +int scmi_xfer_raw_wait_for_message_response(struct scmi_chan_info *cinfo, + struct scmi_xfer *xfer, + unsigned int timeout_ms) +{ + int ret; + struct scmi_info *info = handle_to_scmi_info(cinfo->handle); + struct device *dev = info->dev; + + ret = scmi_wait_for_reply(dev, info->desc, cinfo, xfer, timeout_ms); + if (ret) + dev_dbg(dev, "timed out in RAW response - HDR:%08X\n", + pack_scmi_header(&xfer->hdr)); + + return ret; +} + +/** * do_xfer() - Do one transfer * * @ph: Pointer to SCMI protocol handle -- 2.7.4