// SPDX-License-Identifier: GPL-2.0-only
/*
 * Qualcomm Peripheral Image Loader helpers
 *
 * Copyright (C) 2016 Linaro Ltd
 * Copyright (C) 2015 Sony Mobile Communications Inc
 * Copyright (c) 2012-2013, The Linux Foundation. All rights reserved.
 */

#include <linux/firmware.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/notifier.h>
#include <linux/remoteproc.h>
#include <linux/remoteproc/qcom_rproc.h>
#include <linux/rpmsg/qcom_glink.h>
#include <linux/rpmsg/qcom_smd.h>
#include <linux/slab.h>
#include <linux/soc/qcom/mdt_loader.h>

#include "remoteproc_internal.h"
#include "qcom_common.h"

#define to_glink_subdev(d) container_of(d, struct qcom_rproc_glink, subdev)
#define to_smd_subdev(d) container_of(d, struct qcom_rproc_subdev, subdev)
#define to_ssr_subdev(d) container_of(d, struct qcom_rproc_ssr, subdev)

struct qcom_ssr_subsystem {
	const char *name;
	struct srcu_notifier_head notifier_list;
	struct list_head list;
};

static LIST_HEAD(qcom_ssr_subsystem_list);
static DEFINE_MUTEX(qcom_ssr_subsys_lock);

static int glink_subdev_start(struct rproc_subdev *subdev)
{
	struct qcom_rproc_glink *glink = to_glink_subdev(subdev);

	glink->edge = qcom_glink_smem_register(glink->dev, glink->node);

	return PTR_ERR_OR_ZERO(glink->edge);
}

static void glink_subdev_stop(struct rproc_subdev *subdev, bool crashed)
{
	struct qcom_rproc_glink *glink = to_glink_subdev(subdev);

	qcom_glink_smem_unregister(glink->edge);
	glink->edge = NULL;
}

static void glink_subdev_unprepare(struct rproc_subdev *subdev)
{
	struct qcom_rproc_glink *glink = to_glink_subdev(subdev);

	qcom_glink_ssr_notify(glink->ssr_name);
}

/**
 * qcom_add_glink_subdev() - try to add a GLINK subdevice to rproc
 * @rproc:	rproc handle to parent the subdevice
 * @glink:	reference to a GLINK subdev context
 * @ssr_name:	identifier of the associated remoteproc for ssr notifications
 */
void qcom_add_glink_subdev(struct rproc *rproc, struct qcom_rproc_glink *glink,
			   const char *ssr_name)
{
	struct device *dev = &rproc->dev;

	glink->node = of_get_child_by_name(dev->parent->of_node, "glink-edge");
	if (!glink->node)
		return;

	glink->ssr_name = kstrdup_const(ssr_name, GFP_KERNEL);
	if (!glink->ssr_name)
		return;

	glink->dev = dev;
	glink->subdev.start = glink_subdev_start;
	glink->subdev.stop = glink_subdev_stop;
	glink->subdev.unprepare = glink_subdev_unprepare;

	rproc_add_subdev(rproc, &glink->subdev);
}
EXPORT_SYMBOL_GPL(qcom_add_glink_subdev);

/**
 * qcom_remove_glink_subdev() - remove a GLINK subdevice from rproc
 * @rproc:	rproc handle
 * @glink:	reference to a GLINK subdev context
 */
void qcom_remove_glink_subdev(struct rproc *rproc, struct qcom_rproc_glink *glink)
{
	if (!glink->node)
		return;

	rproc_remove_subdev(rproc, &glink->subdev);
	kfree_const(glink->ssr_name);
	of_node_put(glink->node);
}
EXPORT_SYMBOL_GPL(qcom_remove_glink_subdev);

/**
 * qcom_register_dump_segments() - register segments for coredump
 * @rproc:	remoteproc handle
 * @fw:		firmware header
 *
 * Register all segments of the ELF in the remoteproc coredump segment list
 *
 * Return: 0 on success, negative errno on failure.
 */
int qcom_register_dump_segments(struct rproc *rproc,
				const struct firmware *fw)
{
	const struct elf32_phdr *phdrs;
	const struct elf32_phdr *phdr;
	const struct elf32_hdr *ehdr;
	int ret;
	int i;

	ehdr = (struct elf32_hdr *)fw->data;
	phdrs = (struct elf32_phdr *)(ehdr + 1);

	for (i = 0; i < ehdr->e_phnum; i++) {
		phdr = &phdrs[i];

		if (phdr->p_type != PT_LOAD)
			continue;

		if ((phdr->p_flags & QCOM_MDT_TYPE_MASK) == QCOM_MDT_TYPE_HASH)
			continue;

		if (!phdr->p_memsz)
			continue;

		ret = rproc_coredump_add_segment(rproc, phdr->p_paddr,
						 phdr->p_memsz);
		if (ret)
			return ret;
	}

	return 0;
}
EXPORT_SYMBOL_GPL(qcom_register_dump_segments);

static int smd_subdev_start(struct rproc_subdev *subdev)
{
	struct qcom_rproc_subdev *smd = to_smd_subdev(subdev);

	smd->edge = qcom_smd_register_edge(smd->dev, smd->node);

	return PTR_ERR_OR_ZERO(smd->edge);
}

static void smd_subdev_stop(struct rproc_subdev *subdev, bool crashed)
{
	struct qcom_rproc_subdev *smd = to_smd_subdev(subdev);

	qcom_smd_unregister_edge(smd->edge);
	smd->edge = NULL;
}

/**
 * qcom_add_smd_subdev() - try to add a SMD subdevice to rproc
 * @rproc:	rproc handle to parent the subdevice
 * @smd:	reference to a Qualcomm subdev context
 */
void qcom_add_smd_subdev(struct rproc *rproc, struct qcom_rproc_subdev *smd)
{
	struct device *dev = &rproc->dev;

	smd->node = of_get_child_by_name(dev->parent->of_node, "smd-edge");
	if (!smd->node)
		return;

	smd->dev = dev;
	smd->subdev.start = smd_subdev_start;
	smd->subdev.stop = smd_subdev_stop;

	rproc_add_subdev(rproc, &smd->subdev);
}
EXPORT_SYMBOL_GPL(qcom_add_smd_subdev);

/**
 * qcom_remove_smd_subdev() - remove the smd subdevice from rproc
 * @rproc:	rproc handle
 * @smd:	the SMD subdevice to remove
 */
void qcom_remove_smd_subdev(struct rproc *rproc, struct qcom_rproc_subdev *smd)
{
	if (!smd->node)
		return;

	rproc_remove_subdev(rproc, &smd->subdev);
	of_node_put(smd->node);
}
EXPORT_SYMBOL_GPL(qcom_remove_smd_subdev);

static struct qcom_ssr_subsystem *qcom_ssr_get_subsys(const char *name)
{
	struct qcom_ssr_subsystem *info;

	mutex_lock(&qcom_ssr_subsys_lock);
	/* Match in the global qcom_ssr_subsystem_list with name */
	list_for_each_entry(info, &qcom_ssr_subsystem_list, list)
		if (!strcmp(info->name, name))
			goto out;

	info = kzalloc(sizeof(*info), GFP_KERNEL);
	if (!info) {
		info = ERR_PTR(-ENOMEM);
		goto out;
	}
	info->name = kstrdup_const(name, GFP_KERNEL);
	srcu_init_notifier_head(&info->notifier_list);

	/* Add to global notification list */
	list_add_tail(&info->list, &qcom_ssr_subsystem_list);

out:
	mutex_unlock(&qcom_ssr_subsys_lock);
	return info;
}

/**
 * qcom_register_ssr_notifier() - register SSR notification handler
 * @name:	Subsystem's SSR name
 * @nb:		notifier_block to be invoked upon subsystem's state change
 *
 * This registers the @nb notifier block as part the notifier chain for a
 * remoteproc associated with @name. The notifier block's callback
 * will be invoked when the remote processor's SSR events occur
 * (pre/post startup and pre/post shutdown).
 *
 * Return: a subsystem cookie on success, ERR_PTR on failure.
 */
void *qcom_register_ssr_notifier(const char *name, struct notifier_block *nb)
{
	struct qcom_ssr_subsystem *info;

	info = qcom_ssr_get_subsys(name);
	if (IS_ERR(info))
		return info;

	srcu_notifier_chain_register(&info->notifier_list, nb);

	return &info->notifier_list;
}
EXPORT_SYMBOL_GPL(qcom_register_ssr_notifier);

/**
 * qcom_unregister_ssr_notifier() - unregister SSR notification handler
 * @notify:	subsystem cookie returned from qcom_register_ssr_notifier
 * @nb:		notifier_block to unregister
 *
 * This function will unregister the notifier from the particular notifier
 * chain.
 *
 * Return: 0 on success, %ENOENT otherwise.
 */
int qcom_unregister_ssr_notifier(void *notify, struct notifier_block *nb)
{
	return srcu_notifier_chain_unregister(notify, nb);
}
EXPORT_SYMBOL_GPL(qcom_unregister_ssr_notifier);

static int ssr_notify_prepare(struct rproc_subdev *subdev)
{
	struct qcom_rproc_ssr *ssr = to_ssr_subdev(subdev);
	struct qcom_ssr_notify_data data = {
		.name = ssr->info->name,
		.crashed = false,
	};

	srcu_notifier_call_chain(&ssr->info->notifier_list,
				 QCOM_SSR_BEFORE_POWERUP, &data);
	return 0;
}

static int ssr_notify_start(struct rproc_subdev *subdev)
{
	struct qcom_rproc_ssr *ssr = to_ssr_subdev(subdev);
	struct qcom_ssr_notify_data data = {
		.name = ssr->info->name,
		.crashed = false,
	};

	srcu_notifier_call_chain(&ssr->info->notifier_list,
				 QCOM_SSR_AFTER_POWERUP, &data);
	return 0;
}

static void ssr_notify_stop(struct rproc_subdev *subdev, bool crashed)
{
	struct qcom_rproc_ssr *ssr = to_ssr_subdev(subdev);
	struct qcom_ssr_notify_data data = {
		.name = ssr->info->name,
		.crashed = crashed,
	};

	srcu_notifier_call_chain(&ssr->info->notifier_list,
				 QCOM_SSR_BEFORE_SHUTDOWN, &data);
}

static void ssr_notify_unprepare(struct rproc_subdev *subdev)
{
	struct qcom_rproc_ssr *ssr = to_ssr_subdev(subdev);
	struct qcom_ssr_notify_data data = {
		.name = ssr->info->name,
		.crashed = false,
	};

	srcu_notifier_call_chain(&ssr->info->notifier_list,
				 QCOM_SSR_AFTER_SHUTDOWN, &data);
}

/**
 * qcom_add_ssr_subdev() - register subdevice as restart notification source
 * @rproc:	rproc handle
 * @ssr:	SSR subdevice handle
 * @ssr_name:	identifier to use for notifications originating from @rproc
 *
 * As the @ssr is registered with the @rproc SSR events will be sent to all
 * registered listeners for the remoteproc when it's SSR events occur
 * (pre/post startup and pre/post shutdown).
 */
void qcom_add_ssr_subdev(struct rproc *rproc, struct qcom_rproc_ssr *ssr,
			 const char *ssr_name)
{
	struct qcom_ssr_subsystem *info;

	info = qcom_ssr_get_subsys(ssr_name);
	if (IS_ERR(info)) {
		dev_err(&rproc->dev, "Failed to add ssr subdevice\n");
		return;
	}

	ssr->info = info;
	ssr->subdev.prepare = ssr_notify_prepare;
	ssr->subdev.start = ssr_notify_start;
	ssr->subdev.stop = ssr_notify_stop;
	ssr->subdev.unprepare = ssr_notify_unprepare;

	rproc_add_subdev(rproc, &ssr->subdev);
}
EXPORT_SYMBOL_GPL(qcom_add_ssr_subdev);

/**
 * qcom_remove_ssr_subdev() - remove subdevice as restart notification source
 * @rproc:	rproc handle
 * @ssr:	SSR subdevice handle
 */
void qcom_remove_ssr_subdev(struct rproc *rproc, struct qcom_rproc_ssr *ssr)
{
	rproc_remove_subdev(rproc, &ssr->subdev);
	ssr->info = NULL;
}
EXPORT_SYMBOL_GPL(qcom_remove_ssr_subdev);

MODULE_DESCRIPTION("Qualcomm Remoteproc helper driver");
MODULE_LICENSE("GPL v2");