[PATCH 3/3] drm/tegra: Add NVDEC driver

[Jon Hunter]

On 13/02/2021 10:15, Mikko Perttunen wrote:
> Add support for booting and using NVDEC on Tegra210, Tegra186
> and Tegra194 to the Host1x and TegraDRM drivers. Booting in
> secure mode is not currently supported.
> 
> Signed-off-by: Mikko Perttunen <mperttunen at nvidia.com>
> ---
>  drivers/gpu/drm/tegra/Makefile |   3 +-
>  drivers/gpu/drm/tegra/drm.c    |   4 +
>  drivers/gpu/drm/tegra/drm.h    |   1 +
>  drivers/gpu/drm/tegra/nvdec.c  | 497 +++++++++++++++++++++++++++++++++
>  drivers/gpu/host1x/dev.c       |  12 +
>  include/linux/host1x.h         |   1 +
>  6 files changed, 517 insertions(+), 1 deletion(-)
>  create mode 100644 drivers/gpu/drm/tegra/nvdec.c

...

> +static int nvdec_probe(struct platform_device *pdev)
> +{
> +	struct device *dev = &pdev->dev;
> +	struct host1x_syncpt **syncpts;
> +	struct resource *regs;
> +	struct nvdec *nvdec;
> +	int err;
> +
> +	/* inherit DMA mask from host1x parent */
> +	err = dma_coerce_mask_and_coherent(dev, *dev->parent->dma_mask);
> +	if (err < 0) {
> +		dev_err(&pdev->dev, "failed to set DMA mask: %d\n", err);
> +		return err;
> +	}
> +
> +	nvdec = devm_kzalloc(dev, sizeof(*nvdec), GFP_KERNEL);
> +	if (!nvdec)
> +		return -ENOMEM;
> +
> +	nvdec->config = of_device_get_match_data(dev);
> +
> +	syncpts = devm_kzalloc(dev, sizeof(*syncpts), GFP_KERNEL);
> +	if (!syncpts)
> +		return -ENOMEM;
> +
> +	regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +	if (!regs) {
> +		dev_err(&pdev->dev, "failed to get registers\n");
> +		return -ENXIO;
> +	}
> +
> +	nvdec->regs = devm_ioremap_resource(dev, regs);
> +	if (IS_ERR(nvdec->regs))
> +		return PTR_ERR(nvdec->regs);
> +

We should be able to use devm_platform_get_and_ioremap_resource() here.

> +	nvdec->clk = devm_clk_get(dev, NULL);
> +	if (IS_ERR(nvdec->clk)) {
> +		dev_err(&pdev->dev, "failed to get clock\n");
> +		return PTR_ERR(nvdec->clk);
> +	}
> +
> +	if (!dev->pm_domain) {

Looks like the power-domain is required by device-tree and so do we need
this?

> +		nvdec->rst = devm_reset_control_get(dev, "nvdec");
> +		if (IS_ERR(nvdec->rst)) {
> +			dev_err(&pdev->dev, "failed to get reset\n");
> +			return PTR_ERR(nvdec->rst);
> +		}
> +	}
> +
> +	nvdec->falcon.dev = dev;
> +	nvdec->falcon.regs = nvdec->regs;
> +
> +	err = falcon_init(&nvdec->falcon);
> +	if (err < 0)
> +		return err;
> +
> +	platform_set_drvdata(pdev, nvdec);
> +
> +	INIT_LIST_HEAD(&nvdec->client.base.list);
> +	nvdec->client.base.ops = &nvdec_client_ops;
> +	nvdec->client.base.dev = dev;
> +	nvdec->client.base.class = HOST1X_CLASS_NVDEC;
> +	nvdec->client.base.syncpts = syncpts;
> +	nvdec->client.base.num_syncpts = 1;
> +	nvdec->dev = dev;
> +
> +	INIT_LIST_HEAD(&nvdec->client.list);
> +	nvdec->client.version = nvdec->config->version;
> +	nvdec->client.ops = &nvdec_ops;
> +
> +	err = host1x_client_register(&nvdec->client.base);
> +	if (err < 0) {
> +		dev_err(dev, "failed to register host1x client: %d\n", err);
> +		goto exit_falcon;
> +	}
> +
> +	pm_runtime_enable(&pdev->dev);
> +	if (!pm_runtime_enabled(&pdev->dev)) {
> +		err = nvdec_runtime_resume(&pdev->dev);
> +		if (err < 0)
> +			goto unregister_client;
> +	}

pm_runtime should always be enabled for 64-bit Tegra and so we should
not need to check pm_runtime_enabled().

Cheers
Jon

-- 
nvpublic