linux/drivers/remoteproc/qcom_common.c
Rishabh Bhatnagar 5abfe5cf0b remoteproc: qcom: Add per subsystem SSR notification
Currently there is a single notification chain which is called whenever any
remoteproc shuts down. This leads to all the listeners being notified, and
is not an optimal design as kernel drivers might only be interested in
listening to notifications from a particular remoteproc. Create a global
list of remoteproc notification info data structures. This will hold the
name and notifier_list information for a particular remoteproc. The API
to register for notifications will use name argument to retrieve the
notification info data structure and the notifier block will be added to
that data structure's notification chain. Also move from blocking notifier
to srcu notifer based implementation to support dynamic notifier head
creation.

Reviewed-by: Alex Elder <elder@linaro.org>
Co-developed-by: Siddharth Gupta <sidgup@codeaurora.org>
Signed-off-by: Siddharth Gupta <sidgup@codeaurora.org>
Signed-off-by: Rishabh Bhatnagar <rishabhb@codeaurora.org>
Link: https://lore.kernel.org/r/1592965408-16908-2-git-send-email-rishabhb@codeaurora.org
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
2020-07-08 21:45:03 -07:00

321 lines
8.4 KiB
C

// 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/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 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, 0, &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.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");