1 files changed, 186 insertions, 96 deletions

diff --git a/drivers/firmware/arm_scmi/clock.c b/drivers/firmware/arm_scmi/clock.c
index 8f9017206c..2c902835a0 100644
--- a/drivers/firmware/arm_scmi/clock.c
+++ b/drivers/firmware/arm_scmi/clock.c
@@ -2,13 +2,13 @@
 /*
  * System Control and Management Interface (SCMI) Clock Protocol
  *
- * Copyright (C) 2018-2021 ARM Ltd.
+ * Copyright (C) 2018-2022 ARM Ltd.
  */
 
 #include <common.h>
 #include <qsort.h>
 
-#include "common.h"
+#include "protocols.h"
 
 enum scmi_clock_protocol_cmd {
 	CLOCK_ATTRIBUTES = 0x3,
@@ -16,6 +16,7 @@ enum scmi_clock_protocol_cmd {
 	CLOCK_RATE_SET = 0x5,
 	CLOCK_RATE_GET = 0x6,
 	CLOCK_CONFIG_SET = 0x7,
+	CLOCK_NAME_GET = 0x8,
 };
 
 struct scmi_msg_resp_clock_protocol_attributes {
@@ -27,7 +28,9 @@ struct scmi_msg_resp_clock_protocol_attributes {
 struct scmi_msg_resp_clock_attributes {
 	__le32 attributes;
 #define	CLOCK_ENABLE	BIT(0)
-	    u8 name[SCMI_MAX_STR_SIZE];
+#define SUPPORTS_EXTENDED_NAMES(x)		((x) & BIT(29))
+	u8 name[SCMI_SHORT_NAME_MAX_SIZE];
+	__le32 clock_enable_latency;
 };
 
 struct scmi_clock_set_config {
@@ -48,7 +51,7 @@ struct scmi_msg_resp_clock_describe_rates {
 	struct {
 		__le32 value_low;
 		__le32 value_high;
-	} rate[0];
+	} rate[];
 #define RATE_TO_U64(X)		\
 ({				\
 	typeof(X) x = (X);	\
@@ -67,11 +70,15 @@ struct scmi_clock_set_rate {
 	__le32 value_high;
 };
 
+struct scmi_msg_resp_set_rate_complete {
+	__le32 id;
+	__le32 rate_low;
+	__le32 rate_high;
+};
+
 struct clock_info {
 	u32 version;
 	int num_clocks;
-	int max_async_req;
-	unsigned cur_async_req;
 	struct scmi_clock_info *clk;
 };
 
@@ -91,19 +98,19 @@ scmi_clock_protocol_attributes_get(const struct scmi_protocol_handle *ph,
 	attr = t->rx.buf;
 
 	ret = ph->xops->do_xfer(ph, t);
-	if (!ret) {
+	if (!ret)
 		ci->num_clocks = le16_to_cpu(attr->num_clocks);
-		ci->max_async_req = attr->max_async_req;
-	}
 
 	ph->xops->xfer_put(ph, t);
 	return ret;
 }
 
 static int scmi_clock_attributes_get(const struct scmi_protocol_handle *ph,
-				     u32 clk_id, struct scmi_clock_info *clk)
+				     u32 clk_id, struct scmi_clock_info *clk,
+				     u32 version)
 {
 	int ret;
+	u32 attributes;
 	struct scmi_xfer *t;
 	struct scmi_msg_resp_clock_attributes *attr;
 
@@ -116,12 +123,30 @@ static int scmi_clock_attributes_get(const struct scmi_protocol_handle *ph,
 	attr = t->rx.buf;
 
 	ret = ph->xops->do_xfer(ph, t);
-	if (!ret)
-		strlcpy(clk->name, attr->name, SCMI_MAX_STR_SIZE);
-	else
-		clk->name[0] = '\0';
+	if (!ret) {
+		u32 latency = 0;
+		attributes = le32_to_cpu(attr->attributes);
+		strscpy(clk->name, attr->name, SCMI_SHORT_NAME_MAX_SIZE);
+		/* clock_enable_latency field is present only since SCMI v3.1 */
+		if (PROTOCOL_REV_MAJOR(version) >= 0x2)
+			latency = le32_to_cpu(attr->clock_enable_latency);
+		clk->enable_latency = latency ? : U32_MAX;
+	}
 
 	ph->xops->xfer_put(ph, t);
+
+	/*
+	 * If supported overwrite short name with the extended one;
+	 * on error just carry on and use already provided short name.
+	 */
+	if (!ret && PROTOCOL_REV_MAJOR(version) >= 0x2) {
+		if (SUPPORTS_EXTENDED_NAMES(attributes))
+			ph->hops->extended_name_get(ph, CLOCK_NAME_GET, clk_id,
+						    clk->name,
+						    SCMI_MAX_STR_SIZE);
+
+	}
+
 	return ret;
 }
 
@@ -137,80 +162,134 @@ static int rate_cmp_func(const void *_r1, const void *_r2)
 		return 1;
 }
 
-static int
-scmi_clock_describe_rates_get(const struct scmi_protocol_handle *ph, u32 clk_id,
-			      struct scmi_clock_info *clk)
-{
-	u64 *rate = NULL;
-	int ret, cnt;
-	bool rate_discrete = false;
-	u32 tot_rate_cnt = 0, rates_flag;
-	u16 num_returned, num_remaining;
-	struct scmi_xfer *t;
-	struct scmi_msg_clock_describe_rates *clk_desc;
-	struct scmi_msg_resp_clock_describe_rates *rlist;
+struct scmi_clk_ipriv {
+	struct device *dev;
+	u32 clk_id;
+	struct scmi_clock_info *clk;
+};
 
-	ret = ph->xops->xfer_get_init(ph, CLOCK_DESCRIBE_RATES,
-				      sizeof(*clk_desc), 0, &t);
-	if (ret)
-		return ret;
+static void iter_clk_describe_prepare_message(void *message,
+					      const unsigned int desc_index,
+					      const void *priv)
+{
+	struct scmi_msg_clock_describe_rates *msg = message;
+	const struct scmi_clk_ipriv *p = priv;
 
-	clk_desc = t->tx.buf;
-	rlist = t->rx.buf;
+	msg->id = cpu_to_le32(p->clk_id);
+	/* Set the number of rates to be skipped/already read */
+	msg->rate_index = cpu_to_le32(desc_index);
+}
 
-	do {
-		clk_desc->id = cpu_to_le32(clk_id);
-		/* Set the number of rates to be skipped/already read */
-		clk_desc->rate_index = cpu_to_le32(tot_rate_cnt);
+static int
+iter_clk_describe_update_state(struct scmi_iterator_state *st,
+			       const void *response, void *priv)
+{
+	u32 flags;
+	struct scmi_clk_ipriv *p = priv;
+	const struct scmi_msg_resp_clock_describe_rates *r = response;
+
+	flags = le32_to_cpu(r->num_rates_flags);
+	st->num_remaining = NUM_REMAINING(flags);
+	st->num_returned = NUM_RETURNED(flags);
+	p->clk->rate_discrete = RATE_DISCRETE(flags);
+
+	/* Warn about out of spec replies ... */
+	if (!p->clk->rate_discrete &&
+	    (st->num_returned != 3 || st->num_remaining != 0)) {
+		dev_warn(p->dev,
+			 "Out-of-spec CLOCK_DESCRIBE_RATES reply for %s - returned:%d remaining:%d rx_len:%zd\n",
+			 p->clk->name, st->num_returned, st->num_remaining,
+			 st->rx_len);
 
-		ret = ph->xops->do_xfer(ph, t);
-		if (ret)
-			goto err;
+		/*
+		 * A known quirk: a triplet is returned but num_returned != 3
+		 * Check for a safe payload size and fix.
+		 */
+		if (st->num_returned != 3 && st->num_remaining == 0 &&
+		    st->rx_len == sizeof(*r) + sizeof(__le32) * 2 * 3) {
+			st->num_returned = 3;
+			st->num_remaining = 0;
+		} else {
+			dev_err(p->dev,
+				"Cannot fix out-of-spec reply !\n");
+			return -EPROTO;
+		}
+	}
 
-		rates_flag = le32_to_cpu(rlist->num_rates_flags);
-		num_remaining = NUM_REMAINING(rates_flag);
-		rate_discrete = RATE_DISCRETE(rates_flag);
-		num_returned = NUM_RETURNED(rates_flag);
+	return 0;
+}
 
-		if (tot_rate_cnt + num_returned > SCMI_MAX_NUM_RATES) {
-			dev_err(ph->dev, "No. of rates > MAX_NUM_RATES");
+static int
+iter_clk_describe_process_response(const struct scmi_protocol_handle *ph,
+				   const void *response,
+				   struct scmi_iterator_state *st, void *priv)
+{
+	int ret = 0;
+	struct scmi_clk_ipriv *p = priv;
+	const struct scmi_msg_resp_clock_describe_rates *r = response;
+
+	if (!p->clk->rate_discrete) {
+		switch (st->desc_index + st->loop_idx) {
+		case 0:
+			p->clk->range.min_rate = RATE_TO_U64(r->rate[0]);
 			break;
-		}
-
-		if (!rate_discrete) {
-			clk->range.min_rate = RATE_TO_U64(rlist->rate[0]);
-			clk->range.max_rate = RATE_TO_U64(rlist->rate[1]);
-			clk->range.step_size = RATE_TO_U64(rlist->rate[2]);
-			dev_dbg(ph->dev, "Min %llu Max %llu Step %llu Hz\n",
-				clk->range.min_rate, clk->range.max_rate,
-				clk->range.step_size);
+		case 1:
+			p->clk->range.max_rate = RATE_TO_U64(r->rate[1]);
+			break;
+		case 2:
+			p->clk->range.step_size = RATE_TO_U64(r->rate[2]);
+			break;
+		default:
+			ret = -EINVAL;
 			break;
 		}
+	} else {
+		u64 *rate = &p->clk->list.rates[st->desc_index + st->loop_idx];
 
-		rate = &clk->list.rates[tot_rate_cnt];
-		for (cnt = 0; cnt < num_returned; cnt++, rate++) {
-			*rate = RATE_TO_U64(rlist->rate[cnt]);
-			dev_dbg(ph->dev, "Rate %llu Hz\n", *rate);
-		}
+		*rate = RATE_TO_U64(r->rate[st->loop_idx]);
+		p->clk->list.num_rates++;
+	}
 
-		tot_rate_cnt += num_returned;
+	return ret;
+}
 
-		ph->xops->reset_rx_to_maxsz(ph, t);
-		/*
-		 * check for both returned and remaining to avoid infinite
-		 * loop due to buggy firmware
-		 */
-	} while (num_returned && num_remaining);
+static int
+scmi_clock_describe_rates_get(const struct scmi_protocol_handle *ph, u32 clk_id,
+			      struct scmi_clock_info *clk)
+{
+	int ret;
+	void *iter;
+	struct scmi_iterator_ops ops = {
+		.prepare_message = iter_clk_describe_prepare_message,
+		.update_state = iter_clk_describe_update_state,
+		.process_response = iter_clk_describe_process_response,
+	};
+	struct scmi_clk_ipriv cpriv = {
+		.clk_id = clk_id,
+		.clk = clk,
+		.dev = ph->dev,
+	};
+
+	iter = ph->hops->iter_response_init(ph, &ops, SCMI_MAX_NUM_RATES,
+					    CLOCK_DESCRIBE_RATES,
+					    sizeof(struct scmi_msg_clock_describe_rates),
+					    &cpriv);
+	if (IS_ERR(iter))
+		return PTR_ERR(iter);
+
+	ret = ph->hops->iter_response_run(iter);
+	if (ret)
+		return ret;
 
-	if (rate_discrete && rate) {
-		clk->list.num_rates = tot_rate_cnt;
-		qsort(rate, tot_rate_cnt, sizeof(*rate), rate_cmp_func);
+	if (!clk->rate_discrete) {
+		dev_dbg(ph->dev, "Min %llu Max %llu Step %llu Hz\n",
+			clk->range.min_rate, clk->range.max_rate,
+			clk->range.step_size);
+	} else if (clk->list.num_rates) {
+		qsort(clk->list.rates, clk->list.num_rates,
+		     sizeof(clk->list.rates[0]), rate_cmp_func);
 	}
 
-	clk->rate_discrete = rate_discrete;
-
-err:
-	ph->xops->xfer_put(ph, t);
 	return ret;
 }
 
@@ -240,32 +319,20 @@ static int scmi_clock_rate_set(const struct scmi_protocol_handle *ph,
 			       u32 clk_id, u64 rate)
 {
 	int ret;
-	u32 flags = 0;
 	struct scmi_xfer *t;
 	struct scmi_clock_set_rate *cfg;
-	struct clock_info *ci = ph->get_priv(ph);
 
 	ret = ph->xops->xfer_get_init(ph, CLOCK_RATE_SET, sizeof(*cfg), 0, &t);
 	if (ret)
 		return ret;
 
-	if (ci->max_async_req &&
-	    ci->cur_async_req++ < ci->max_async_req)
-		flags |= CLOCK_SET_ASYNC;
-
 	cfg = t->tx.buf;
-	cfg->flags = cpu_to_le32(flags);
+	cfg->flags = cpu_to_le32(0);
 	cfg->id = cpu_to_le32(clk_id);
 	cfg->value_low = cpu_to_le32(rate & 0xffffffff);
 	cfg->value_high = cpu_to_le32(rate >> 32);
 
-	if (flags & CLOCK_SET_ASYNC)
-		ret = ph->xops->do_xfer_with_response(ph, t);
-	else
-		ret = ph->xops->do_xfer(ph, t);
-
-	if (ci->max_async_req)
-		ci->cur_async_req--;
+	ret = ph->xops->do_xfer(ph, t);
 
 	ph->xops->xfer_put(ph, t);
 	return ret;
@@ -273,7 +340,7 @@ static int scmi_clock_rate_set(const struct scmi_protocol_handle *ph,
 
 static int
 scmi_clock_config_set(const struct scmi_protocol_handle *ph, u32 clk_id,
-		      u32 config)
+		      u32 config, bool atomic)
 {
 	int ret;
 	struct scmi_xfer *t;
@@ -296,12 +363,24 @@ scmi_clock_config_set(const struct scmi_protocol_handle *ph, u32 clk_id,
 
 static int scmi_clock_enable(const struct scmi_protocol_handle *ph, u32 clk_id)
 {
-	return scmi_clock_config_set(ph, clk_id, CLOCK_ENABLE);
+	return scmi_clock_config_set(ph, clk_id, CLOCK_ENABLE, false);
 }
 
 static int scmi_clock_disable(const struct scmi_protocol_handle *ph, u32 clk_id)
 {
-	return scmi_clock_config_set(ph, clk_id, 0);
+	return scmi_clock_config_set(ph, clk_id, 0, false);
+}
+
+static int scmi_clock_enable_atomic(const struct scmi_protocol_handle *ph,
+				    u32 clk_id)
+{
+	return scmi_clock_config_set(ph, clk_id, CLOCK_ENABLE, true);
+}
+
+static int scmi_clock_disable_atomic(const struct scmi_protocol_handle *ph,
+				     u32 clk_id)
+{
+	return scmi_clock_config_set(ph, clk_id, 0, true);
 }
 
 static int scmi_clock_count_get(const struct scmi_protocol_handle *ph)
@@ -314,9 +393,13 @@ static int scmi_clock_count_get(const struct scmi_protocol_handle *ph)
 static const struct scmi_clock_info *
 scmi_clock_info_get(const struct scmi_protocol_handle *ph, u32 clk_id)
 {
+	struct scmi_clock_info *clk;
 	struct clock_info *ci = ph->get_priv(ph);
-	struct scmi_clock_info *clk = ci->clk + clk_id;
 
+	if (clk_id >= ci->num_clocks)
+		return NULL;
+
+	clk = ci->clk + clk_id;
 	if (!clk->name[0])
 		return NULL;
 
@@ -330,6 +413,8 @@ static const struct scmi_clk_proto_ops clk_proto_ops = {
 	.rate_set = scmi_clock_rate_set,
 	.enable = scmi_clock_enable,
 	.disable = scmi_clock_disable,
+	.enable_atomic = scmi_clock_enable_atomic,
+	.disable_atomic = scmi_clock_disable_atomic,
 };
 
 static int scmi_clock_protocol_init(const struct scmi_protocol_handle *ph)
@@ -338,25 +423,30 @@ static int scmi_clock_protocol_init(const struct scmi_protocol_handle *ph)
 	int clkid, ret;
 	struct clock_info *cinfo;
 
-	ph->xops->version_get(ph, &version);
+	ret = ph->xops->version_get(ph, &version);
+	if (ret)
+		return ret;
 
 	dev_dbg(ph->dev, "Clock Version %d.%d\n",
 		PROTOCOL_REV_MAJOR(version), PROTOCOL_REV_MINOR(version));
 
-	cinfo = kzalloc(sizeof(*cinfo), GFP_KERNEL);
+	cinfo = devm_kzalloc(ph->dev, sizeof(*cinfo), GFP_KERNEL);
 	if (!cinfo)
 		return -ENOMEM;
 
-	scmi_clock_protocol_attributes_get(ph, cinfo);
+	ret = scmi_clock_protocol_attributes_get(ph, cinfo);
+	if (ret)
+		return ret;
 
-	cinfo->clk = kcalloc(cinfo->num_clocks, sizeof(*cinfo->clk), GFP_KERNEL);
+	cinfo->clk = devm_kcalloc(ph->dev, cinfo->num_clocks,
+				  sizeof(*cinfo->clk), GFP_KERNEL);
 	if (!cinfo->clk)
 		return -ENOMEM;
 
 	for (clkid = 0; clkid < cinfo->num_clocks; clkid++) {
 		struct scmi_clock_info *clk = cinfo->clk + clkid;
 
-		ret = scmi_clock_attributes_get(ph, clkid, clk);
+		ret = scmi_clock_attributes_get(ph, clkid, clk, version);
 		if (!ret)
 			scmi_clock_describe_rates_get(ph, clkid, clk);
 	}