Commit d8283ac2 authored by Marek Vasut's avatar Marek Vasut Committed by Sudeep Holla
Browse files

firmware: arm_scmi: Implement arm,no-completion-irq property 



Implement new property arm,no-completion-irq, which sets all SCMI
operation into poll mode. This is meant to work around uncooperative
SCP implementations, which do not generate completion interrupts.
This applies to mbox/shmem based implementations.

With this property set, such implementations which do not generate
interrupts can be interacted with, until they are fixed to generate
interrupts properly.

Signed-off-by: default avatarMarek Vasut <marek.vasut+renesas@mailbox.org>
Reviewed-by: default avatarCristian Marussi <cristian.marussi@arm.com>
Message-Id: <20260117010241.186685-2-marek.vasut+renesas@mailbox.org>
Signed-off-by: default avatarSudeep Holla <sudeep.holla@kernel.org>
parent 0c5453bf

drivers/firmware/arm_scmi/common.h

+4 −0
Original line number Diff line number Diff line
@@ -235,6 +235,9 @@ struct scmi_transport_ops { 
 *		      to have an execution latency lesser-equal to the threshold

 *		      should be considered for atomic mode operation: such

 *		      decision is finally left up to the SCMI drivers.

 * @no_completion_irq: Flag to indicate that this transport has no completion

 *		       interrupt and has to be polled. This is similar to the

 *		       force_polling below, except this is set via DT property.

 * @force_polling: Flag to force this whole transport to use SCMI core polling

 *		   mechanism instead of completion interrupts even if available.

 * @sync_cmds_completed_on_ret: Flag to indicate that the transport assures
@@ -254,6 +257,7 @@ struct scmi_desc { 
	int max_msg;

	int max_msg_size;

	unsigned int atomic_threshold;

	bool no_completion_irq;

	const bool force_polling;

	const bool sync_cmds_completed_on_ret;

	const bool atomic_enabled;

drivers/firmware/arm_scmi/driver.c

+4 −0
Original line number Diff line number Diff line
@@ -2735,6 +2735,7 @@ static int scmi_chan_setup(struct scmi_info *info, struct device_node *of_node, 
	cinfo->is_p2a = !tx;

	cinfo->rx_timeout_ms = info->desc->max_rx_timeout_ms;

	cinfo->max_msg_size = info->desc->max_msg_size;

	cinfo->no_completion_irq = info->desc->no_completion_irq;



	/* Create a unique name for this transport device */

	snprintf(name, 32, "__scmi_transport_device_%s_%02X",
@@ -3150,6 +3151,9 @@ static const struct scmi_desc *scmi_transport_setup(struct device *dev) 
	if (ret && ret != -EINVAL)

		dev_err(dev, "Malformed arm,max-msg DT property.\n");



	trans->desc.no_completion_irq = of_property_read_bool(dev->of_node,

							      "arm,no-completion-irq");



	dev_info(dev,

		 "SCMI max-rx-timeout: %dms / max-msg-size: %dbytes / max-msg: %d\n",

		 trans->desc.max_rx_timeout_ms, trans->desc.max_msg_size,