firmware: arm_scmi: Add xfer helpers to provide raw access (3095a3e2) · Commits · EulixOS / Software / Kernel

drivers/firmware/arm_scmi/common.h

+12 −0

Original line number	Diff line number	Diff line
		@@ -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

drivers/firmware/arm_scmi/driver.c

+147 −0

Original line number	Diff line number	Diff line
		@@ -450,6 +450,53 @@ scmi_xfer_inflight_register_unlocked(struct scmi_xfer *xfer,
		xfer->pending = true;
		}

		/**
		* 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
		@@ -525,6 +572,63 @@ static struct scmi_xfer scmi_xfer_get(const struct scmi_handle handle,
		return xfer;
		}

		/**
		* 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
		*
		@@ -553,6 +657,23 @@ __scmi_xfer_put(struct scmi_xfers_info minfo, struct scmi_xfer xfer)
		spin_unlock_irqrestore(&minfo->xfer_lock, flags);
		}

		/**
		* 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
		*
		@@ -979,6 +1100,32 @@ static int scmi_wait_for_message_response(struct scmi_chan_info *cinfo,
		info->desc->max_rx_timeout_ms);
		}

		/**
		* 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
		*