Commit 8aa5bcb6 authored by Mikko Perttunen's avatar Mikko Perttunen Committed by Thierry Reding
Browse files

gpu: host1x: Add context device management code 



Add code to register context devices from device tree, allocate them
out and manage their refcounts.

Signed-off-by: default avatarMikko Perttunen <mperttunen@nvidia.com>
Signed-off-by: default avatarThierry Reding <treding@nvidia.com>
parent a72d4b18

drivers/gpu/host1x/Makefile

+3 −0
Original line number Diff line number Diff line
@@ -17,5 +17,8 @@ host1x-y = \ 
	hw/host1x06.o \

	hw/host1x07.o



host1x-$(CONFIG_IOMMU_API) += \

	context.o



obj-$(CONFIG_TEGRA_HOST1X) += host1x.o

obj-$(CONFIG_TEGRA_HOST1X_CONTEXT_BUS) += context_bus.o

drivers/gpu/host1x/context.c

0 → 100644
+160 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0-only

/*

 * Copyright (c) 2021, NVIDIA Corporation.

 */



#include <linux/device.h>

#include <linux/kref.h>

#include <linux/of.h>

#include <linux/of_platform.h>

#include <linux/pid.h>

#include <linux/slab.h>



#include "context.h"

#include "dev.h"



int host1x_memory_context_list_init(struct host1x *host1x)

{

	struct host1x_memory_context_list *cdl = &host1x->context_list;

	struct device_node *node = host1x->dev->of_node;

	struct host1x_memory_context *ctx;

	unsigned int i;

	int err;



	cdl->devs = NULL;

	cdl->len = 0;

	mutex_init(&cdl->lock);



	err = of_property_count_u32_elems(node, "iommu-map");

	if (err < 0)

		return 0;



	cdl->devs = kcalloc(err, sizeof(*cdl->devs), GFP_KERNEL);

	if (!cdl->devs)

		return -ENOMEM;

	cdl->len = err / 4;



	for (i = 0; i < cdl->len; i++) {

		struct iommu_fwspec *fwspec;



		ctx = &cdl->devs[i];



		ctx->host = host1x;



		device_initialize(&ctx->dev);



		/*

		 * Due to an issue with T194 NVENC, only 38 bits can be used.

		 * Anyway, 256GiB of IOVA ought to be enough for anyone.

		 */

		ctx->dma_mask = DMA_BIT_MASK(38);

		ctx->dev.dma_mask = &ctx->dma_mask;

		ctx->dev.coherent_dma_mask = ctx->dma_mask;

		dev_set_name(&ctx->dev, "host1x-ctx.%d", i);

		ctx->dev.bus = &host1x_context_device_bus_type;

		ctx->dev.parent = host1x->dev;



		dma_set_max_seg_size(&ctx->dev, UINT_MAX);



		err = device_add(&ctx->dev);

		if (err) {

			dev_err(host1x->dev, "could not add context device %d: %d\n", i, err);

			goto del_devices;

		}



		err = of_dma_configure_id(&ctx->dev, node, true, &i);

		if (err) {

			dev_err(host1x->dev, "IOMMU configuration failed for context device %d: %d\n",

				i, err);

			device_del(&ctx->dev);

			goto del_devices;

		}



		fwspec = dev_iommu_fwspec_get(&ctx->dev);

		if (!fwspec || !device_iommu_mapped(&ctx->dev)) {

			dev_err(host1x->dev, "Context device %d has no IOMMU!\n", i);

			device_del(&ctx->dev);

			goto del_devices;

		}



		ctx->stream_id = fwspec->ids[0] & 0xffff;

	}



	return 0;



del_devices:

	while (i--)

		device_del(&cdl->devs[i].dev);



	kfree(cdl->devs);

	cdl->len = 0;



	return err;

}



void host1x_memory_context_list_free(struct host1x_memory_context_list *cdl)

{

	unsigned int i;



	for (i = 0; i < cdl->len; i++)

		device_del(&cdl->devs[i].dev);



	kfree(cdl->devs);

	cdl->len = 0;

}



struct host1x_memory_context *host1x_memory_context_alloc(struct host1x *host1x,

							  struct pid *pid)

{

	struct host1x_memory_context_list *cdl = &host1x->context_list;

	struct host1x_memory_context *free = NULL;

	int i;



	if (!cdl->len)

		return ERR_PTR(-EOPNOTSUPP);



	mutex_lock(&cdl->lock);



	for (i = 0; i < cdl->len; i++) {

		struct host1x_memory_context *cd = &cdl->devs[i];



		if (cd->owner == pid) {

			refcount_inc(&cd->ref);

			mutex_unlock(&cdl->lock);

			return cd;

		} else if (!cd->owner && !free) {

			free = cd;

		}

	}



	if (!free) {

		mutex_unlock(&cdl->lock);

		return ERR_PTR(-EBUSY);

	}



	refcount_set(&free->ref, 1);

	free->owner = get_pid(pid);



	mutex_unlock(&cdl->lock);



	return free;

}

EXPORT_SYMBOL_GPL(host1x_memory_context_alloc);



void host1x_memory_context_get(struct host1x_memory_context *cd)

{

	refcount_inc(&cd->ref);

}

EXPORT_SYMBOL_GPL(host1x_memory_context_get);



void host1x_memory_context_put(struct host1x_memory_context *cd)

{

	struct host1x_memory_context_list *cdl = &cd->host->context_list;



	if (refcount_dec_and_mutex_lock(&cd->ref, &cdl->lock)) {

		put_pid(cd->owner);

		cd->owner = NULL;

		mutex_unlock(&cdl->lock);

	}

}

EXPORT_SYMBOL_GPL(host1x_memory_context_put);

drivers/gpu/host1x/context.h

0 → 100644
+38 −0
Original line number Diff line number Diff line 
/* SPDX-License-Identifier: GPL-2.0-only */

/*

 * Host1x context devices

 *

 * Copyright (c) 2020, NVIDIA Corporation.

 */



#ifndef __HOST1X_CONTEXT_H

#define __HOST1X_CONTEXT_H



#include <linux/mutex.h>

#include <linux/refcount.h>



struct host1x;



extern struct bus_type host1x_context_device_bus_type;



struct host1x_memory_context_list {

	struct mutex lock;

	struct host1x_memory_context *devs;

	unsigned int len;

};



#ifdef CONFIG_IOMMU_API

int host1x_memory_context_list_init(struct host1x *host1x);

void host1x_memory_context_list_free(struct host1x_memory_context_list *cdl);

#else

static inline int host1x_memory_context_list_init(struct host1x *host1x)

{

	return 0;

}



static inline void host1x_memory_context_list_free(struct host1x_memory_context_list *cdl)

{

}

#endif



#endif

drivers/gpu/host1x/dev.c

+11 −1
Original line number Diff line number Diff line
@@ -28,6 +28,7 @@ 


#include "bus.h"

#include "channel.h"

#include "context.h"

#include "debug.h"

#include "dev.h"

#include "intr.h"
@@ -503,10 +504,16 @@ static int host1x_probe(struct platform_device *pdev) 
		goto iommu_exit;

	}



	err = host1x_memory_context_list_init(host);

	if (err) {

		dev_err(&pdev->dev, "failed to initialize context list\n");

		goto free_channels;

	}



	err = host1x_syncpt_init(host);

	if (err) {

		dev_err(&pdev->dev, "failed to initialize syncpts\n");

		goto free_channels;

		goto free_contexts;

	}



	err = host1x_intr_init(host, syncpt_irq);
@@ -550,6 +557,8 @@ static int host1x_probe(struct platform_device *pdev) 
	host1x_intr_deinit(host);

deinit_syncpt:

	host1x_syncpt_deinit(host);

free_contexts:

	host1x_memory_context_list_free(&host->context_list);

free_channels:

	host1x_channel_list_free(&host->channel_list);

iommu_exit:
@@ -571,6 +580,7 @@ static int host1x_remove(struct platform_device *pdev) 


	host1x_intr_deinit(host);

	host1x_syncpt_deinit(host);

	host1x_memory_context_list_free(&host->context_list);

	host1x_channel_list_free(&host->channel_list);

	host1x_iommu_exit(host);

	host1x_bo_cache_destroy(&host->cache);

drivers/gpu/host1x/dev.h

+2 −0
Original line number Diff line number Diff line
@@ -14,6 +14,7 @@ 


#include "cdma.h"

#include "channel.h"

#include "context.h"

#include "intr.h"

#include "job.h"

#include "syncpt.h"
@@ -141,6 +142,7 @@ struct host1x { 
	struct mutex syncpt_mutex;



	struct host1x_channel_list channel_list;

	struct host1x_memory_context_list context_list;



	struct dentry *debugfs;