1 files changed, 513 insertions, 0 deletions
diff --git a/drivers/soc/qcom/rpmh.c b/drivers/soc/qcom/rpmh.c
new file mode 100644
index 000000000000..c7beb6841289
--- /dev/null
+++ b/drivers/soc/qcom/rpmh.c
@@ -0,0 +1,513 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2016-2018, The Linux Foundation. All rights reserved.
+ */
+
+#include <linux/atomic.h>
+#include <linux/bug.h>
+#include <linux/interrupt.h>
+#include <linux/jiffies.h>
+#include <linux/kernel.h>
+#include <linux/list.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/types.h>
+#include <linux/wait.h>
+
+#include <soc/qcom/rpmh.h>
+
+#include "rpmh-internal.h"
+
+#define RPMH_TIMEOUT_MS			msecs_to_jiffies(10000)
+
+#define DEFINE_RPMH_MSG_ONSTACK(dev, s, q, name)	\
+	struct rpmh_request name = {			\
+		.msg = {				\
+			.state = s,			\
+			.cmds = name.cmd,		\
+			.num_cmds = 0,			\
+			.wait_for_compl = true,		\
+		},					\
+		.cmd = { { 0 } },			\
+		.completion = q,			\
+		.dev = dev,				\
+		.needs_free = false,				\
+	}
+
+#define ctrlr_to_drv(ctrlr) container_of(ctrlr, struct rsc_drv, client)
+
+/**
+ * struct cache_req: the request object for caching
+ *
+ * @addr: the address of the resource
+ * @sleep_val: the sleep vote
+ * @wake_val: the wake vote
+ * @list: linked list obj
+ */
+struct cache_req {
+	u32 addr;
+	u32 sleep_val;
+	u32 wake_val;
+	struct list_head list;
+};
+
+/**
+ * struct batch_cache_req - An entry in our batch catch
+ *
+ * @list: linked list obj
+ * @count: number of messages
+ * @rpm_msgs: the messages
+ */
+
+struct batch_cache_req {
+	struct list_head list;
+	int count;
+	struct rpmh_request rpm_msgs[];
+};
+
+static struct rpmh_ctrlr *get_rpmh_ctrlr(const struct device *dev)
+{
+	struct rsc_drv *drv = dev_get_drvdata(dev->parent);
+
+	return &drv->client;
+}
+
+void rpmh_tx_done(const struct tcs_request *msg, int r)
+{
+	struct rpmh_request *rpm_msg = container_of(msg, struct rpmh_request,
+						    msg);
+	struct completion *compl = rpm_msg->completion;
+
+	rpm_msg->err = r;
+
+	if (r)
+		dev_err(rpm_msg->dev, "RPMH TX fail in msg addr=%#x, err=%d\n",
+			rpm_msg->msg.cmds[0].addr, r);
+
+	if (!compl)
+		goto exit;
+
+	/* Signal the blocking thread we are done */
+	complete(compl);
+
+exit:
+	if (rpm_msg->needs_free)
+		kfree(rpm_msg);
+}
+
+static struct cache_req *__find_req(struct rpmh_ctrlr *ctrlr, u32 addr)
+{
+	struct cache_req *p, *req = NULL;
+
+	list_for_each_entry(p, &ctrlr->cache, list) {
+		if (p->addr == addr) {
+			req = p;
+			break;
+		}
+	}
+
+	return req;
+}
+
+static struct cache_req *cache_rpm_request(struct rpmh_ctrlr *ctrlr,
+					   enum rpmh_state state,
+					   struct tcs_cmd *cmd)
+{
+	struct cache_req *req;
+	unsigned long flags;
+
+	spin_lock_irqsave(&ctrlr->cache_lock, flags);
+	req = __find_req(ctrlr, cmd->addr);
+	if (req)
+		goto existing;
+
+	req = kzalloc(sizeof(*req), GFP_ATOMIC);
+	if (!req) {
+		req = ERR_PTR(-ENOMEM);
+		goto unlock;
+	}
+
+	req->addr = cmd->addr;
+	req->sleep_val = req->wake_val = UINT_MAX;
+	INIT_LIST_HEAD(&req->list);
+	list_add_tail(&req->list, &ctrlr->cache);
+
+existing:
+	switch (state) {
+	case RPMH_ACTIVE_ONLY_STATE:
+		if (req->sleep_val != UINT_MAX)
+			req->wake_val = cmd->data;
+		break;
+	case RPMH_WAKE_ONLY_STATE:
+		req->wake_val = cmd->data;
+		break;
+	case RPMH_SLEEP_STATE:
+		req->sleep_val = cmd->data;
+		break;
+	default:
+		break;
+	}
+
+	ctrlr->dirty = true;
+unlock:
+	spin_unlock_irqrestore(&ctrlr->cache_lock, flags);
+
+	return req;
+}
+
+/**
+ * __rpmh_write: Cache and send the RPMH request
+ *
+ * @dev: The device making the request
+ * @state: Active/Sleep request type
+ * @rpm_msg: The data that needs to be sent (cmds).
+ *
+ * Cache the RPMH request and send if the state is ACTIVE_ONLY.
+ * SLEEP/WAKE_ONLY requests are not sent to the controller at
+ * this time. Use rpmh_flush() to send them to the controller.
+ */
+static int __rpmh_write(const struct device *dev, enum rpmh_state state,
+			struct rpmh_request *rpm_msg)
+{
+	struct rpmh_ctrlr *ctrlr = get_rpmh_ctrlr(dev);
+	int ret = -EINVAL;
+	struct cache_req *req;
+	int i;
+
+	rpm_msg->msg.state = state;
+
+	/* Cache the request in our store and link the payload */
+	for (i = 0; i < rpm_msg->msg.num_cmds; i++) {
+		req = cache_rpm_request(ctrlr, state, &rpm_msg->msg.cmds[i]);
+		if (IS_ERR(req))
+			return PTR_ERR(req);
+	}
+
+	rpm_msg->msg.state = state;
+
+	if (state == RPMH_ACTIVE_ONLY_STATE) {
+		WARN_ON(irqs_disabled());
+		ret = rpmh_rsc_send_data(ctrlr_to_drv(ctrlr), &rpm_msg->msg);
+	} else {
+		ret = rpmh_rsc_write_ctrl_data(ctrlr_to_drv(ctrlr),
+				&rpm_msg->msg);
+		/* Clean up our call by spoofing tx_done */
+		rpmh_tx_done(&rpm_msg->msg, ret);
+	}
+
+	return ret;
+}
+
+static int __fill_rpmh_msg(struct rpmh_request *req, enum rpmh_state state,
+		const struct tcs_cmd *cmd, u32 n)
+{
+	if (!cmd || !n || n > MAX_RPMH_PAYLOAD)
+		return -EINVAL;
+
+	memcpy(req->cmd, cmd, n * sizeof(*cmd));
+
+	req->msg.state = state;
+	req->msg.cmds = req->cmd;
+	req->msg.num_cmds = n;
+
+	return 0;
+}
+
+/**
+ * rpmh_write_async: Write a set of RPMH commands
+ *
+ * @dev: The device making the request
+ * @state: Active/sleep set
+ * @cmd: The payload data
+ * @n: The number of elements in payload
+ *
+ * Write a set of RPMH commands, the order of commands is maintained
+ * and will be sent as a single shot.
+ */
+int rpmh_write_async(const struct device *dev, enum rpmh_state state,
+		     const struct tcs_cmd *cmd, u32 n)
+{
+	struct rpmh_request *rpm_msg;
+	int ret;
+
+	rpm_msg = kzalloc(sizeof(*rpm_msg), GFP_ATOMIC);
+	if (!rpm_msg)
+		return -ENOMEM;
+	rpm_msg->needs_free = true;
+
+	ret = __fill_rpmh_msg(rpm_msg, state, cmd, n);
+	if (ret) {
+		kfree(rpm_msg);
+		return ret;
+	}
+
+	return __rpmh_write(dev, state, rpm_msg);
+}
+EXPORT_SYMBOL(rpmh_write_async);
+
+/**
+ * rpmh_write: Write a set of RPMH commands and block until response
+ *
+ * @rc: The RPMH handle got from rpmh_get_client
+ * @state: Active/sleep set
+ * @cmd: The payload data
+ * @n: The number of elements in @cmd
+ *
+ * May sleep. Do not call from atomic contexts.
+ */
+int rpmh_write(const struct device *dev, enum rpmh_state state,
+	       const struct tcs_cmd *cmd, u32 n)
+{
+	DECLARE_COMPLETION_ONSTACK(compl);
+	DEFINE_RPMH_MSG_ONSTACK(dev, state, &compl, rpm_msg);
+	int ret;
+
+	if (!cmd || !n || n > MAX_RPMH_PAYLOAD)
+		return -EINVAL;
+
+	memcpy(rpm_msg.cmd, cmd, n * sizeof(*cmd));
+	rpm_msg.msg.num_cmds = n;
+
+	ret = __rpmh_write(dev, state, &rpm_msg);
+	if (ret)
+		return ret;
+
+	ret = wait_for_completion_timeout(&compl, RPMH_TIMEOUT_MS);
+	WARN_ON(!ret);
+	return (ret > 0) ? 0 : -ETIMEDOUT;
+}
+EXPORT_SYMBOL(rpmh_write);
+
+static void cache_batch(struct rpmh_ctrlr *ctrlr, struct batch_cache_req *req)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&ctrlr->cache_lock, flags);
+	list_add_tail(&req->list, &ctrlr->batch_cache);
+	spin_unlock_irqrestore(&ctrlr->cache_lock, flags);
+}
+
+static int flush_batch(struct rpmh_ctrlr *ctrlr)
+{
+	struct batch_cache_req *req;
+	const struct rpmh_request *rpm_msg;
+	unsigned long flags;
+	int ret = 0;
+	int i;
+
+	/* Send Sleep/Wake requests to the controller, expect no response */
+	spin_lock_irqsave(&ctrlr->cache_lock, flags);
+	list_for_each_entry(req, &ctrlr->batch_cache, list) {
+		for (i = 0; i < req->count; i++) {
+			rpm_msg = req->rpm_msgs + i;
+			ret = rpmh_rsc_write_ctrl_data(ctrlr_to_drv(ctrlr),
+						       &rpm_msg->msg);
+			if (ret)
+				break;
+		}
+	}
+	spin_unlock_irqrestore(&ctrlr->cache_lock, flags);
+
+	return ret;
+}
+
+static void invalidate_batch(struct rpmh_ctrlr *ctrlr)
+{
+	struct batch_cache_req *req, *tmp;
+	unsigned long flags;
+
+	spin_lock_irqsave(&ctrlr->cache_lock, flags);
+	list_for_each_entry_safe(req, tmp, &ctrlr->batch_cache, list)
+		kfree(req);
+	INIT_LIST_HEAD(&ctrlr->batch_cache);
+	spin_unlock_irqrestore(&ctrlr->cache_lock, flags);
+}
+
+/**
+ * rpmh_write_batch: Write multiple sets of RPMH commands and wait for the
+ * batch to finish.
+ *
+ * @dev: the device making the request
+ * @state: Active/sleep set
+ * @cmd: The payload data
+ * @n: The array of count of elements in each batch, 0 terminated.
+ *
+ * Write a request to the RSC controller without caching. If the request
+ * state is ACTIVE, then the requests are treated as completion request
+ * and sent to the controller immediately. The function waits until all the
+ * commands are complete. If the request was to SLEEP or WAKE_ONLY, then the
+ * request is sent as fire-n-forget and no ack is expected.
+ *
+ * May sleep. Do not call from atomic contexts for ACTIVE_ONLY requests.
+ */
+int rpmh_write_batch(const struct device *dev, enum rpmh_state state,
+		     const struct tcs_cmd *cmd, u32 *n)
+{
+	struct batch_cache_req *req;
+	struct rpmh_request *rpm_msgs;
+	DECLARE_COMPLETION_ONSTACK(compl);
+	struct rpmh_ctrlr *ctrlr = get_rpmh_ctrlr(dev);
+	unsigned long time_left;
+	int count = 0;
+	int ret, i, j;
+
+	if (!cmd || !n)
+		return -EINVAL;
+
+	while (n[count] > 0)
+		count++;
+	if (!count)
+		return -EINVAL;
+
+	req = kzalloc(sizeof(*req) + count * sizeof(req->rpm_msgs[0]),
+		      GFP_ATOMIC);
+	if (!req)
+		return -ENOMEM;
+	req->count = count;
+	rpm_msgs = req->rpm_msgs;
+
+	for (i = 0; i < count; i++) {
+		__fill_rpmh_msg(rpm_msgs + i, state, cmd, n[i]);
+		cmd += n[i];
+	}
+
+	if (state != RPMH_ACTIVE_ONLY_STATE) {
+		cache_batch(ctrlr, req);
+		return 0;
+	}
+
+	for (i = 0; i < count; i++) {
+		rpm_msgs[i].completion = &compl;
+		ret = rpmh_rsc_send_data(ctrlr_to_drv(ctrlr), &rpm_msgs[i].msg);
+		if (ret) {
+			pr_err("Error(%d) sending RPMH message addr=%#x\n",
+			       ret, rpm_msgs[i].msg.cmds[0].addr);
+			for (j = i; j < count; j++)
+				rpmh_tx_done(&rpm_msgs[j].msg, ret);
+			break;
+		}
+	}
+
+	time_left = RPMH_TIMEOUT_MS;
+	for (i = 0; i < count; i++) {
+		time_left = wait_for_completion_timeout(&compl, time_left);
+		if (!time_left) {
+			/*
+			 * Better hope they never finish because they'll signal
+			 * the completion on our stack and that's bad once
+			 * we've returned from the function.
+			 */
+			WARN_ON(1);
+			ret = -ETIMEDOUT;
+			goto exit;
+		}
+	}
+
+exit:
+	kfree(req);
+
+	return ret;
+}
+EXPORT_SYMBOL(rpmh_write_batch);
+
+static int is_req_valid(struct cache_req *req)
+{
+	return (req->sleep_val != UINT_MAX &&
+		req->wake_val != UINT_MAX &&
+		req->sleep_val != req->wake_val);
+}
+
+static int send_single(const struct device *dev, enum rpmh_state state,
+		       u32 addr, u32 data)
+{
+	DEFINE_RPMH_MSG_ONSTACK(dev, state, NULL, rpm_msg);
+	struct rpmh_ctrlr *ctrlr = get_rpmh_ctrlr(dev);
+
+	/* Wake sets are always complete and sleep sets are not */
+	rpm_msg.msg.wait_for_compl = (state == RPMH_WAKE_ONLY_STATE);
+	rpm_msg.cmd[0].addr = addr;
+	rpm_msg.cmd[0].data = data;
+	rpm_msg.msg.num_cmds = 1;
+
+	return rpmh_rsc_write_ctrl_data(ctrlr_to_drv(ctrlr), &rpm_msg.msg);
+}
+
+/**
+ * rpmh_flush: Flushes the buffered active and sleep sets to TCS
+ *
+ * @dev: The device making the request
+ *
+ * Return: -EBUSY if the controller is busy, probably waiting on a response
+ * to a RPMH request sent earlier.
+ *
+ * This function is always called from the sleep code from the last CPU
+ * that is powering down the entire system. Since no other RPMH API would be
+ * executing at this time, it is safe to run lockless.
+ */
+int rpmh_flush(const struct device *dev)
+{
+	struct cache_req *p;
+	struct rpmh_ctrlr *ctrlr = get_rpmh_ctrlr(dev);
+	int ret;
+
+	if (!ctrlr->dirty) {
+		pr_debug("Skipping flush, TCS has latest data.\n");
+		return 0;
+	}
+
+	/* First flush the cached batch requests */
+	ret = flush_batch(ctrlr);
+	if (ret)
+		return ret;
+
+	/*
+	 * Nobody else should be calling this function other than system PM,
+	 * hence we can run without locks.
+	 */
+	list_for_each_entry(p, &ctrlr->cache, list) {
+		if (!is_req_valid(p)) {
+			pr_debug("%s: skipping RPMH req: a:%#x s:%#x w:%#x",
+				 __func__, p->addr, p->sleep_val, p->wake_val);
+			continue;
+		}
+		ret = send_single(dev, RPMH_SLEEP_STATE, p->addr, p->sleep_val);
+		if (ret)
+			return ret;
+		ret = send_single(dev, RPMH_WAKE_ONLY_STATE,
+				  p->addr, p->wake_val);
+		if (ret)
+			return ret;
+	}
+
+	ctrlr->dirty = false;
+
+	return 0;
+}
+EXPORT_SYMBOL(rpmh_flush);
+
+/**
+ * rpmh_invalidate: Invalidate all sleep and active sets
+ * sets.
+ *
+ * @dev: The device making the request
+ *
+ * Invalidate the sleep and active values in the TCS blocks.
+ */
+int rpmh_invalidate(const struct device *dev)
+{
+	struct rpmh_ctrlr *ctrlr = get_rpmh_ctrlr(dev);
+	int ret;
+
+	invalidate_batch(ctrlr);
+	ctrlr->dirty = true;
+
+	do {
+		ret = rpmh_rsc_invalidate(ctrlr_to_drv(ctrlr));
+	} while (ret == -EAGAIN);
+
+	return ret;
+}
+EXPORT_SYMBOL(rpmh_invalidate);