Commit ac8aaf34 authored by Sudeep Holla's avatar Sudeep Holla
Browse files

firmware: arm_scmi: Add discovery of SCMI v2.0 performance fastchannels 



SCMI v2.0 adds support for "FastChannel", a lightweight unidirectional
channel that is dedicated to a single SCMI message type for controlling
a specific platform resource. They do not use a message header as they
are specialized for a single message.

Only PERFORMANCE_LIMITS_{SET,GET} and PERFORMANCE_LEVEL_{SET,GET}
commands are supported over fastchannels. As they are optional, they
need to be discovered by PERFORMANCE_DESCRIBE_FASTCHANNEL command.
Further {LIMIT,LEVEL}_SET commands can have optional doorbell support.

Add support for discovery of these fastchannels.

Cc: Ionela Voinescu <Ionela.Voinescu@arm.com>
Cc: Chris Redpath <Chris.Redpath@arm.com>
Cc: Quentin Perret <Quentin.Perret@arm.com>
Reviewed-by: default avatarPeng Fan <peng.fan@nxp.com>
Signed-off-by: default avatarSudeep Holla <sudeep.holla@arm.com>
parent aa90ac45

drivers/firmware/arm_scmi/perf.c

+149 −4
Original line number Diff line number Diff line
@@ -5,7 +5,9 @@ 
 * Copyright (C) 2018 ARM Ltd.

 */



#include <linux/bits.h>

#include <linux/of.h>

#include <linux/io.h>

#include <linux/platform_device.h>

#include <linux/pm_opp.h>

#include <linux/sort.h>
@@ -21,6 +23,7 @@ enum scmi_performance_protocol_cmd { 
	PERF_LEVEL_GET = 0x8,

	PERF_NOTIFY_LIMITS = 0x9,

	PERF_NOTIFY_LEVEL = 0xa,

	PERF_DESCRIBE_FASTCHANNEL = 0xb,

};



struct scmi_opp {
@@ -44,6 +47,7 @@ struct scmi_msg_resp_perf_domain_attributes { 
#define SUPPORTS_SET_PERF_LVL(x)	((x) & BIT(30))

#define SUPPORTS_PERF_LIMIT_NOTIFY(x)	((x) & BIT(29))

#define SUPPORTS_PERF_LEVEL_NOTIFY(x)	((x) & BIT(28))

#define SUPPORTS_PERF_FASTCHANNELS(x)	((x) & BIT(27))

	__le32 rate_limit_us;

	__le32 sustained_freq_khz;

	__le32 sustained_perf_level;
@@ -87,17 +91,56 @@ struct scmi_msg_resp_perf_describe_levels { 
	} opp[0];

};



struct scmi_perf_get_fc_info {

	__le32 domain;

	__le32 message_id;

};



struct scmi_msg_resp_perf_desc_fc {

	__le32 attr;

#define SUPPORTS_DOORBELL(x)		((x) & BIT(0))

#define DOORBELL_REG_WIDTH(x)		FIELD_GET(GENMASK(2, 1), (x))

	__le32 rate_limit;

	__le32 chan_addr_low;

	__le32 chan_addr_high;

	__le32 chan_size;

	__le32 db_addr_low;

	__le32 db_addr_high;

	__le32 db_set_lmask;

	__le32 db_set_hmask;

	__le32 db_preserve_lmask;

	__le32 db_preserve_hmask;

};



struct scmi_fc_db_info {

	int width;

	u64 set;

	u64 mask;

	void __iomem *addr;

};



struct scmi_fc_info {

	void __iomem *level_set_addr;

	void __iomem *limit_set_addr;

	void __iomem *level_get_addr;

	void __iomem *limit_get_addr;

	struct scmi_fc_db_info *level_set_db;

	struct scmi_fc_db_info *limit_set_db;

};



struct perf_dom_info {

	bool set_limits;

	bool set_perf;

	bool perf_limit_notify;

	bool perf_level_notify;

	bool perf_fastchannels;

	u32 opp_count;

	u32 sustained_freq_khz;

	u32 sustained_perf_level;

	u32 mult_factor;

	char name[SCMI_MAX_STR_SIZE];

	struct scmi_opp opp[MAX_OPPS];

	struct scmi_fc_info *fc_info;

};



struct scmi_perf_info {
@@ -162,6 +205,7 @@ scmi_perf_domain_attributes_get(const struct scmi_handle *handle, u32 domain, 
		dom_info->set_perf = SUPPORTS_SET_PERF_LVL(flags);

		dom_info->perf_limit_notify = SUPPORTS_PERF_LIMIT_NOTIFY(flags);

		dom_info->perf_level_notify = SUPPORTS_PERF_LEVEL_NOTIFY(flags);

		dom_info->perf_fastchannels = SUPPORTS_PERF_FASTCHANNELS(flags);

		dom_info->sustained_freq_khz =

					le32_to_cpu(attr->sustained_freq_khz);

		dom_info->sustained_perf_level =
@@ -343,6 +387,104 @@ static int scmi_perf_level_get(const struct scmi_handle *handle, u32 domain, 
	return ret;

}



static bool scmi_perf_fc_size_is_valid(u32 msg, u32 size)

{

	if ((msg == PERF_LEVEL_GET || msg == PERF_LEVEL_SET) && size == 4)

		return true;

	if ((msg == PERF_LIMITS_GET || msg == PERF_LIMITS_SET) && size == 8)

		return true;

	return false;

}



static void

scmi_perf_domain_desc_fc(const struct scmi_handle *handle, u32 domain,

			 u32 message_id, void __iomem **p_addr,

			 struct scmi_fc_db_info **p_db)

{

	int ret;

	u32 flags;

	u64 phys_addr;

	u8 size;

	void __iomem *addr;

	struct scmi_xfer *t;

	struct scmi_fc_db_info *db;

	struct scmi_perf_get_fc_info *info;

	struct scmi_msg_resp_perf_desc_fc *resp;



	if (!p_addr)

		return;



	ret = scmi_xfer_get_init(handle, PERF_DESCRIBE_FASTCHANNEL,

				 SCMI_PROTOCOL_PERF,

				 sizeof(*info), sizeof(*resp), &t);

	if (ret)

		return;



	info = t->tx.buf;

	info->domain = cpu_to_le32(domain);

	info->message_id = cpu_to_le32(message_id);



	ret = scmi_do_xfer(handle, t);

	if (ret)

		goto err_xfer;



	resp = t->rx.buf;

	flags = le32_to_cpu(resp->attr);

	size = le32_to_cpu(resp->chan_size);

	if (!scmi_perf_fc_size_is_valid(message_id, size))

		goto err_xfer;



	phys_addr = le32_to_cpu(resp->chan_addr_low);

	phys_addr |= (u64)le32_to_cpu(resp->chan_addr_high) << 32;

	addr = devm_ioremap(handle->dev, phys_addr, size);

	if (!addr)

		goto err_xfer;

	*p_addr = addr;



	if (p_db && SUPPORTS_DOORBELL(flags)) {

		db = devm_kzalloc(handle->dev, sizeof(*db), GFP_KERNEL);

		if (!db)

			goto err_xfer;



		size = 1 << DOORBELL_REG_WIDTH(flags);

		phys_addr = le32_to_cpu(resp->db_addr_low);

		phys_addr |= (u64)le32_to_cpu(resp->db_addr_high) << 32;

		addr = devm_ioremap(handle->dev, phys_addr, size);

		if (!addr)

			goto err_xfer;



		db->addr = addr;

		db->width = size;

		db->set = le32_to_cpu(resp->db_set_lmask);

		db->set |= (u64)le32_to_cpu(resp->db_set_hmask) << 32;

		db->mask = le32_to_cpu(resp->db_preserve_lmask);

		db->mask |= (u64)le32_to_cpu(resp->db_preserve_hmask) << 32;

		*p_db = db;

	}

err_xfer:

	scmi_xfer_put(handle, t);

}



static void scmi_perf_domain_init_fc(const struct scmi_handle *handle,

				     u32 domain, struct scmi_fc_info **p_fc)

{

	struct scmi_fc_info *fc;



	fc = devm_kzalloc(handle->dev, sizeof(*fc), GFP_KERNEL);

	if (!fc)

		return;



	scmi_perf_domain_desc_fc(handle, domain, PERF_LEVEL_SET,

				 &fc->level_set_addr, &fc->level_set_db);

	scmi_perf_domain_desc_fc(handle, domain, PERF_LEVEL_GET,

				 &fc->level_get_addr, NULL);

	scmi_perf_domain_desc_fc(handle, domain, PERF_LIMITS_SET,

				 &fc->limit_set_addr, &fc->limit_set_db);

	scmi_perf_domain_desc_fc(handle, domain, PERF_LIMITS_GET,

				 &fc->limit_get_addr, NULL);

	*p_fc = fc;

}



/* Device specific ops */

static int scmi_dev_domain_id(struct device *dev)

{
@@ -494,6 +636,9 @@ static int scmi_perf_protocol_init(struct scmi_handle *handle) 


		scmi_perf_domain_attributes_get(handle, domain, dom);

		scmi_perf_describe_levels_get(handle, domain, dom);



		if (dom->perf_fastchannels)

			scmi_perf_domain_init_fc(handle, domain, &dom->fc_info);

	}



	handle->perf_ops = &perf_ops;

CRA Git | Maintained and supported by SUSTech CRA and CCSE