gpu: host1x: Add context bus

The context bus is a "dummy" bus that contains struct devices that
correspond to IOMMU contexts assigned through Host1x to processes.

Even when host1x itself is built as a module, the bus is registered
in built-in code so that the built-in ARM SMMU driver is able to
reference it.

Signed-off-by: Mikko Perttunen <mperttunen@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
This commit is contained in:
Mikko Perttunen 2022-05-16 11:52:51 +03:00 committed by Thierry Reding
parent cb7e1abc2c
commit 597b89d30b
5 changed files with 53 additions and 2 deletions

View file

@ -2,7 +2,6 @@
# drm/tegra depends on host1x, so if both drivers are built-in care must be
# taken to initialize them in the correct order. Link order is the only way
# to ensure this currently.
obj-$(CONFIG_TEGRA_HOST1X) += host1x/
obj-y += drm/ vga/
obj-y += host1x/ drm/ vga/
obj-$(CONFIG_IMX_IPUV3_CORE) += ipu-v3/
obj-$(CONFIG_TRACE_GPU_MEM) += trace/

View file

@ -1,8 +1,13 @@
# SPDX-License-Identifier: GPL-2.0-only
config TEGRA_HOST1X_CONTEXT_BUS
bool
config TEGRA_HOST1X
tristate "NVIDIA Tegra host1x driver"
depends on ARCH_TEGRA || (ARM && COMPILE_TEST)
select DMA_SHARED_BUFFER
select TEGRA_HOST1X_CONTEXT_BUS
select IOMMU_IOVA
help
Driver for the NVIDIA Tegra host1x hardware.

View file

@ -18,3 +18,4 @@ host1x-y = \
hw/host1x07.o
obj-$(CONFIG_TEGRA_HOST1X) += host1x.o
obj-$(CONFIG_TEGRA_HOST1X_CONTEXT_BUS) += context_bus.o

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@ -0,0 +1,31 @@
// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (c) 2021, NVIDIA Corporation.
*/
#include <linux/device.h>
#include <linux/of.h>
struct bus_type host1x_context_device_bus_type = {
.name = "host1x-context",
};
EXPORT_SYMBOL_GPL(host1x_context_device_bus_type);
static int __init host1x_context_device_bus_init(void)
{
int err;
if (!of_machine_is_compatible("nvidia,tegra186") &&
!of_machine_is_compatible("nvidia,tegra194") &&
!of_machine_is_compatible("nvidia,tegra234"))
return 0;
err = bus_register(&host1x_context_device_bus_type);
if (err < 0) {
pr_err("bus type registration failed: %d\n", err);
return err;
}
return 0;
}
postcore_initcall(host1x_context_device_bus_init);

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@ -0,0 +1,15 @@
/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
* Copyright (c) 2021, NVIDIA Corporation. All rights reserved.
*/
#ifndef __LINUX_HOST1X_CONTEXT_BUS_H
#define __LINUX_HOST1X_CONTEXT_BUS_H
#include <linux/device.h>
#ifdef CONFIG_TEGRA_HOST1X_CONTEXT_BUS
extern struct bus_type host1x_context_device_bus_type;
#endif
#endif