accel: add accel dummy driveraccel_v5

Signed-off-by: Oded Gabbay <ogabbay@kernel.org>

6 files changed, 176 insertions, 0 deletions

diff --git a/drivers/Makefile b/drivers/Makefile
index bdf1c66141c9bd..d2de100753c213 100644
--- a/drivers/Makefile
+++ b/drivers/Makefile
@@ -62,6 +62,9 @@ obj-y				+= iommu/
 # gpu/ comes after char for AGP vs DRM startup and after iommu
 obj-y				+= gpu/
 
+# accel is part of drm so it must come after gpu
+obj-$(CONFIG_DRM_ACCEL)		+= accel/
+
 obj-$(CONFIG_CONNECTOR)		+= connector/
 
 # i810fb and intelfb depend on char/agp/
diff --git a/drivers/accel/Kconfig b/drivers/accel/Kconfig
index c9ce849b2984af..4fc7729b35f2e9 100644
--- a/drivers/accel/Kconfig
+++ b/drivers/accel/Kconfig
@@ -22,3 +22,5 @@ menuconfig DRM_ACCEL
 	  major number than GPUs, and will be exposed to user-space using
 	  different device files, called accel/accel* (in /dev, sysfs
 	  and debugfs).
+
+source "drivers/accel/dummy/Kconfig"
diff --git a/drivers/accel/Makefile b/drivers/accel/Makefile
new file mode 100644
index 00000000000000..0477cb9867b331
--- /dev/null
+++ b/drivers/accel/Makefile
@@ -0,0 +1,7 @@
+# SPDX-License-Identifier: GPL-2.0
+
+# Makefile for the accel framework. This framework provides support for
+# compute acceleration devices, such as, but not limited to, Machine-Learning
+# and Deep-Learning acceleration devices
+
+obj-$(CONFIG_ACCEL_DUMMY)	+= dummy/
diff --git a/drivers/accel/dummy/Kconfig b/drivers/accel/dummy/Kconfig
new file mode 100644
index 00000000000000..5b871b0d8084af
--- /dev/null
+++ b/drivers/accel/dummy/Kconfig
@@ -0,0 +1,15 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+config ACCEL_DUMMY
+	tristate "Drive for a dummy compute accelerator"
+	depends on DRM_ACCEL
+	help
+	  An example of a compute accelerator driver that registers with drm
+	  as a compute accelerator.
+
+	  This driver does not actually do anything.
+
+	  If unsure, say N.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called accel_dummy.
diff --git a/drivers/accel/dummy/Makefile b/drivers/accel/dummy/Makefile
new file mode 100644
index 00000000000000..c2b9706bffe50f
--- /dev/null
+++ b/drivers/accel/dummy/Makefile
@@ -0,0 +1,5 @@
+# SPDX-License-Identifier: GPL-2.0-only
+
+accel_dummy-y += dummy_drv.o
+
+obj-$(CONFIG_ACCEL_DUMMY) := accel_dummy.o
diff --git a/drivers/accel/dummy/dummy_drv.c b/drivers/accel/dummy/dummy_drv.c
new file mode 100644
index 00000000000000..1852577ce43d82
--- /dev/null
+++ b/drivers/accel/dummy/dummy_drv.c
@@ -0,0 +1,144 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/dma-mapping.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+
+#include <drm/drm_accel.h>
+#include <drm/drm_drv.h>
+#include <drm/drm_ioctl.h>
+#include <drm/drm_print.h>
+
+#define DRIVER_NAME	"accel_dummy"
+#define DRIVER_DESC	"Driver for a dummy compute accelerator"
+#define DRIVER_DATE	"20221022"
+#define DRIVER_MAJOR	1
+#define DRIVER_MINOR	0
+
+MODULE_AUTHOR("Oded Gabbay");
+MODULE_DESCRIPTION("Driver for a dummy compute accelerator");
+MODULE_LICENSE("GPL");
+
+static void accel_dummy_debugfs_init(struct drm_minor *minor);
+
+static struct platform_device *accel_dummy_drm;
+
+DEFINE_DRM_ACCEL_FOPS(accel_dummy_driver_fops);
+
+static const struct drm_driver accel_dummy_drm_driver = {
+	.driver_features	= DRIVER_COMPUTE_ACCEL,
+	.fops			= &accel_dummy_driver_fops,
+	.debugfs_init           = accel_dummy_debugfs_init,
+	.name			= DRIVER_NAME,
+	.desc			= DRIVER_DESC,
+	.date			= DRIVER_DATE,
+	.major			= DRIVER_MAJOR,
+	.minor			= DRIVER_MINOR,
+};
+
+static void accel_dummy_debugfs_init(struct drm_minor *minor)
+{
+	DRM_INFO("%s called\n", __func__);
+}
+
+static int accel_dummy_pdev_probe(struct platform_device *pdev)
+{
+	struct drm_device *drm;
+	struct device *dev;
+	int ret;
+
+	DRM_INFO("%s called\n", __func__);
+
+	dev = &pdev->dev;
+
+	drm = drm_dev_alloc(&accel_dummy_drm_driver, dev);
+	if (IS_ERR(drm))
+		return PTR_ERR(drm);
+
+	dma_set_max_seg_size(dev, SZ_2G);
+
+	dev_set_drvdata(dev, drm);
+
+	ret = drm_dev_register(drm, 0);
+	if (ret)
+		goto out_put;
+
+	return 0;
+
+out_put:
+	drm_dev_put(drm);
+
+	return ret;
+}
+
+static int accel_dummy_remove(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct drm_device *drm = dev_get_drvdata(dev);
+
+	DRM_INFO("%s called\n", __func__);
+
+	drm_dev_unregister(drm);
+
+	drm_dev_put(drm);
+
+	return 0;
+}
+
+static struct platform_driver accel_dummy_platform_driver = {
+	.probe      = accel_dummy_pdev_probe,
+	.remove     = accel_dummy_remove,
+	.driver     = {
+		.name   = "accel_dummy",
+	},
+};
+
+static void __exit accel_dummy_exit(void)
+{
+	DRM_INFO("%s called\n", __func__);
+
+	if (IS_ERR_OR_NULL(accel_dummy_drm)) {
+		DRM_INFO("accel_dummy_drm wasn't initialized\n");
+		return;
+	}
+
+	platform_device_unregister(accel_dummy_drm);
+	platform_driver_unregister(&accel_dummy_platform_driver);
+
+	accel_dummy_drm = NULL;
+}
+
+static int __init accel_dummy_init(void)
+{
+	struct platform_device *pdev;
+	int ret;
+
+	DRM_INFO("%s called\n", __func__);
+
+	ret = platform_driver_register(&accel_dummy_platform_driver);
+	if (ret != 0)
+		return ret;
+
+	pdev = platform_device_alloc("accel_dummy", PLATFORM_DEVID_NONE);
+	if (!pdev) {
+		ret = -ENOMEM;
+		goto unregister_platform_driver;
+	}
+
+	ret = platform_device_add(pdev);
+	if (ret) {
+		platform_device_put(pdev);
+		goto unregister_platform_driver;
+	}
+
+	accel_dummy_drm = pdev;
+
+	return 0;
+
+unregister_platform_driver:
+	platform_driver_unregister(&accel_dummy_platform_driver);
+	return ret;
+}
+
+module_init(accel_dummy_init);
+module_exit(accel_dummy_exit);