On 1/14/26 2:46 AM, Tomeu Vizoso wrote:

Some SoCs from Texas Instruments contain DSPs that can be used for general compute tasks.

This driver provides a drm/accel UABI to userspace for submitting jobs to the DSP cores and managing the input, output and intermediate memory.

Signed-off-by: Tomeu Vizoso tomeu@tomeuvizoso.net

Documentation/accel/thames/index.rst | 28 +++++ MAINTAINERS | 9 ++ drivers/accel/Kconfig | 1 + drivers/accel/Makefile | 3 +- drivers/accel/thames/Kconfig | 26 +++++ drivers/accel/thames/Makefile | 9 ++ drivers/accel/thames/thames_core.c | 155 ++++++++++++++++++++++++++ drivers/accel/thames/thames_core.h | 53 +++++++++ drivers/accel/thames/thames_device.c | 93 ++++++++++++++++ drivers/accel/thames/thames_device.h | 46 ++++++++ drivers/accel/thames/thames_drv.c | 155 ++++++++++++++++++++++++++ drivers/accel/thames/thames_drv.h | 21 ++++ drivers/accel/thames/thames_ipc.h | 204 +++++++++++++++++++++++++++++++++++ drivers/accel/thames/thames_rpmsg.c | 155 ++++++++++++++++++++++++++ drivers/accel/thames/thames_rpmsg.h | 27 +++++ 15 files changed, 984 insertions(+), 1 deletion(-)

diff --git a/Documentation/accel/thames/index.rst b/Documentation/accel/thames/index.rst new file mode 100644 index 0000000000000000000000000000000000000000..ca8391031f226f7ef1dc210a356c86acbe126c6f --- /dev/null +++ b/Documentation/accel/thames/index.rst @@ -0,0 +1,28 @@ +.. SPDX-License-Identifier: GPL-2.0-only

+============================================================

• accel/thames Driver for the C7x DSPs from Texas Instruments

+============================================================

+The accel/thames driver supports the C7x DSPs inside some Texas Instruments SoCs +such as the J722S. These can be used as accelerators for various workloads, +including machine learning inference.

+This driver controls the power state of the hardware via :doc:`remoteproc </staging/remoteproc>` +and communicates with the firmware running on the DSP via :doc:`rpmsg_virtio </staging/rpmsg_virtio>`. +The kernel driver itself allocates buffers, manages contexts, and submits jobs +to the DSP firmware. Buffers are mapped by the DSP itself using its MMU, +providing memory isolation among different clients.

+The source code for the firmware running on the DSP is available at: +https://gitlab.freedesktop.org/tomeu/thames_firmware/.

+Everything else is done in userspace, as a Gallium driver (also called thames) +that is part of the Mesa3D project: https://docs.mesa3d.org/teflon.html

+If there is more than one core that advertises the same rpmsg_virtio service +name, the driver will load balance jobs between them with drm-gpu-scheduler.

+Hardware currently supported:

+* J722S diff --git a/MAINTAINERS b/MAINTAINERS index dc731d37c8feeff25613c59fe9c929927dadaa7e..a3fc809c797269d0792dfe5202cc1b49f6ff57e9 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -7731,6 +7731,15 @@ F: Documentation/devicetree/bindings/npu/rockchip,rk3588-rknn-core.yaml F: drivers/accel/rocket/ F: include/uapi/drm/rocket_accel.h +DRM ACCEL DRIVER FOR TI C7x DSPS +M: Tomeu Vizoso tomeu@tomeuvizoso.net +L: dri-devel@lists.freedesktop.org +S: Supported +T: git https://gitlab.freedesktop.org/drm/misc/kernel.git +F: Documentation/accel/thames/ +F: drivers/accel/thames/ +F: include/uapi/drm/thames_accel.h

• DRM COMPUTE ACCELERATORS DRIVERS AND FRAMEWORK M: Oded Gabbay ogabbay@kernel.org L: dri-devel@lists.freedesktop.org

diff --git a/drivers/accel/Kconfig b/drivers/accel/Kconfig index bdf48ccafcf21b2fd685ec963e39e256196e6e17..cb49c71cd4e4a4220624f7041a75ba950a1a2ee1 100644 --- a/drivers/accel/Kconfig +++ b/drivers/accel/Kconfig @@ -30,5 +30,6 @@ source "drivers/accel/habanalabs/Kconfig" source "drivers/accel/ivpu/Kconfig" source "drivers/accel/qaic/Kconfig" source "drivers/accel/rocket/Kconfig" +source "drivers/accel/thames/Kconfig" endif diff --git a/drivers/accel/Makefile b/drivers/accel/Makefile index 1d3a7251b950f39e2ae600a2fc07a3ef7e41831e..8472989cbe22746f1e7292d2401fa0f7424a6c15 100644 --- a/drivers/accel/Makefile +++ b/drivers/accel/Makefile @@ -5,4 +5,5 @@ obj-$(CONFIG_DRM_ACCEL_ARM_ETHOSU) += ethosu/ obj-$(CONFIG_DRM_ACCEL_HABANALABS) += habanalabs/ obj-$(CONFIG_DRM_ACCEL_IVPU) += ivpu/ obj-$(CONFIG_DRM_ACCEL_QAIC) += qaic/ -obj-$(CONFIG_DRM_ACCEL_ROCKET) += rocket/ \ No newline at end of file +obj-$(CONFIG_DRM_ACCEL_ROCKET) += rocket/ +obj-$(CONFIG_DRM_ACCEL_THAMES) += thames/ \ No newline at end of file diff --git a/drivers/accel/thames/Kconfig b/drivers/accel/thames/Kconfig new file mode 100644 index 0000000000000000000000000000000000000000..50e0b6ac2a16a942ba8463333991f5b0161b99ac --- /dev/null +++ b/drivers/accel/thames/Kconfig @@ -0,0 +1,26 @@ +# SPDX-License-Identifier: GPL-2.0-only

+config DRM_ACCEL_THAMES

• tristate "Thames (support for TI C7x DSP accelerators)"
• depends on DRM_ACCEL
• depends on TI_K3_R5_REMOTEPROC || COMPILE_TEST

COMPILE_TEST part shouldn't be needed here, TI_K3_R5_REMOTEPROC can be built under COMPILE_TEST so TI_K3_R5_REMOTEPROC would just be enabled to test.

• depends on RPMSG
• depends on MMU
• select DRM_SCHED
• select DRM_GEM_SHMEM_HELPER
• help

•  Choose this option if you have a Texas Instruments SoC that contains
  

•  C7x DSP cores that can be used as compute accelerators. This includes
  

•  SoCs such as the AM62A, J721E, J721S2, and J784S4.
  

•  The C7x DSP cores can be used for general-purpose compute acceleration
  

•  and are exposed through the DRM accel subsystem.
  

•  The interface exposed to userspace is described in
  

•  include/uapi/drm/thames_accel.h and is used by the Thames userspace
  

•  driver in Mesa3D.
  

•  If unsure, say N.
  

•  To compile this driver as a module, choose M here: the
  

•  module will be called thames.
  

diff --git a/drivers/accel/thames/Makefile b/drivers/accel/thames/Makefile new file mode 100644 index 0000000000000000000000000000000000000000..7ccd8204f0f5ea800f30e84b319f355be948109d --- /dev/null +++ b/drivers/accel/thames/Makefile @@ -0,0 +1,9 @@ +# SPDX-License-Identifier: GPL-2.0-only

+obj-$(CONFIG_DRM_ACCEL_THAMES) := thames.o

+thames-y := \

• thames_core.o \
• thames_device.o \
• thames_drv.o \
• thames_rpmsg.o

diff --git a/drivers/accel/thames/thames_core.c b/drivers/accel/thames/thames_core.c new file mode 100644 index 0000000000000000000000000000000000000000..92af1d68063116bcfa28a33960cbe829029fc1bf --- /dev/null +++ b/drivers/accel/thames/thames_core.c @@ -0,0 +1,155 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* Copyright 2026 Texas Instruments Incorporated - https://www.ti.com/ */

+#include "linux/remoteproc.h" +#include <linux/dev_printk.h> +#include <linux/err.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/platform_device.h> +#include <linux/completion.h> +#include <linux/jiffies.h> +#include <linux/rpmsg.h>

+#include "thames_core.h" +#include "thames_device.h" +#include "thames_rpmsg.h"

+/* Shift to convert bytes to megabytes (divide by 1048576) */ +#define THAMES_BYTES_TO_MB_SHIFT 20

Seems unused/unneeded.

[...]

+static const struct rpmsg_device_id thames_rpmsg_id_table[] = { { .name = THAMES_SERVICE_NAME },

• 						{} };
  

Some odd formatting here.

+static struct rpmsg_driver thames_rpmsg_driver = {

• .drv = {

• .name = "thames",
  

• .owner = THIS_MODULE,
  

Above line shoulnd't be needed.

Andrew