// SPDX-License-Identifier: GPL-2.0-only/* * Tegra host1x Channel * * Copyright (c) 2010-2013, NVIDIA Corporation. */ #include <linux/slab.h>#include <linux/module.h> #include "channel.h"#include "dev.h"#include "job.h" /* Constructor for the host1x device list */int host1x_channel_list_init(struct host1x_channel_list *chlist,			     unsigned int num_channels){	chlist->channels = kzalloc_objs(struct host1x_channel, num_channels);	if (!chlist->channels)		return -ENOMEM; 	chlist->allocated_channels = bitmap_zalloc(num_channels, GFP_KERNEL);	if (!chlist->allocated_channels) {		kfree(chlist->channels);		return -ENOMEM;	} 	mutex_init(&chlist->lock); 	return 0;} void host1x_channel_list_free(struct host1x_channel_list *chlist){	bitmap_free(chlist->allocated_channels);	kfree(chlist->channels);} int host1x_job_submit(struct host1x_job *job){	struct host1x *host = dev_get_drvdata(job->channel->dev->parent); 	return host1x_hw_channel_submit(host, job);}EXPORT_SYMBOL(host1x_job_submit); struct host1x_channel *host1x_channel_get(struct host1x_channel *channel){	kref_get(&channel->refcount); 	return channel;}EXPORT_SYMBOL(host1x_channel_get); /** * host1x_channel_get_index() - Attempt to get channel reference by index * @host: Host1x device object * @index: Index of channel * * If channel number @index is currently allocated, increase its refcount * and return a pointer to it. Otherwise, return NULL. */struct host1x_channel *host1x_channel_get_index(struct host1x *host,						unsigned int index){	struct host1x_channel *ch = &host->channel_list.channels[index]; 	if (!kref_get_unless_zero(&ch->refcount))		return NULL; 	return ch;} void host1x_channel_stop(struct host1x_channel *channel){	struct host1x *host = dev_get_drvdata(channel->dev->parent); 	host1x_hw_cdma_stop(host, &channel->cdma);}EXPORT_SYMBOL(host1x_channel_stop); /** * host1x_channel_stop_all() - disable CDMA on allocated channels * @host: host1x instance * * Stop CDMA on allocated channels */void host1x_channel_stop_all(struct host1x *host){	struct host1x_channel_list *chlist = &host->channel_list;	int bit; 	mutex_lock(&chlist->lock); 	for_each_set_bit(bit, chlist->allocated_channels, host->info->nb_channels)		host1x_channel_stop(&chlist->channels[bit]); 	mutex_unlock(&chlist->lock);} static void release_channel(struct kref *kref){	struct host1x_channel *channel =		container_of(kref, struct host1x_channel, refcount);	struct host1x *host = dev_get_drvdata(channel->dev->parent);	struct host1x_channel_list *chlist = &host->channel_list; 	host1x_hw_cdma_stop(host, &channel->cdma);	host1x_cdma_deinit(&channel->cdma); 	clear_bit(channel->id, chlist->allocated_channels);} void host1x_channel_put(struct host1x_channel *channel){	kref_put(&channel->refcount, release_channel);}EXPORT_SYMBOL(host1x_channel_put); static struct host1x_channel *acquire_unused_channel(struct host1x *host){	struct host1x_channel_list *chlist = &host->channel_list;	unsigned int max_channels = host->info->nb_channels;	unsigned int index; 	mutex_lock(&chlist->lock); 	index = find_first_zero_bit(chlist->allocated_channels, max_channels);	if (index >= max_channels) {		mutex_unlock(&chlist->lock);		dev_err(host->dev, "failed to find free channel\n");		return NULL;	} 	chlist->channels[index].id = index; 	set_bit(index, chlist->allocated_channels); 	mutex_unlock(&chlist->lock); 	return &chlist->channels[index];} /** * host1x_channel_request() - Allocate a channel * @client: Host1x client this channel will be used to send commands to * * Allocates a new host1x channel for @client. May return NULL if CDMA * initialization fails. */struct host1x_channel *host1x_channel_request(struct host1x_client *client){	struct host1x *host = dev_get_drvdata(client->dev->parent);	struct host1x_channel_list *chlist = &host->channel_list;	struct host1x_channel *channel;	int err; 	channel = acquire_unused_channel(host);	if (!channel)		return NULL; 	kref_init(&channel->refcount);	mutex_init(&channel->submitlock);	channel->client = client;	channel->dev = client->dev; 	err = host1x_hw_channel_init(host, channel, channel->id);	if (err < 0)		goto fail; 	err = host1x_cdma_init(&channel->cdma);	if (err < 0)		goto fail; 	return channel; fail:	clear_bit(channel->id, chlist->allocated_channels); 	dev_err(client->dev, "failed to initialize channel\n"); 	return NULL;}EXPORT_SYMBOL(host1x_channel_request);