Re: [PATCH v2] media: mtk-vcodec: fix builds when remoteproc is disabled

[Hans Verkuil]

Hi Alexandre,

On 04/10/2020 14:22, Alexandre Courbot wrote:
> The addition of MT8183 support added a dependency on the SCP remoteproc
> module. However the initial patch used the "select" Kconfig directive,
> which may result in the SCP module to not be compiled if remoteproc was
> disabled. In such a case, mtk-vcodec would try to link against
> non-existent SCP symbols. "select" was clearly misused here as explained
> in kconfig-language.txt.
> 
> Replace this by a "depends" directive on at least one of the VPU and
> SCP modules, to allow the driver to be compiled as long as one of these
> is enabled, and adapt the code to support this new scenario.
> 
> Also adapt the Kconfig text to explain the extra requirements for MT8173
> and MT8183.
> 
> Reported-by: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx>
> Signed-off-by: Alexandre Courbot <acourbot@xxxxxxxxxxxx>
> Acked-by: Randy Dunlap <rdunlap@xxxxxxxxxxxxx> # build-tested
> ---
>  drivers/media/platform/Kconfig                | 10 +--
>  .../media/platform/mtk-vcodec/mtk_vcodec_fw.c | 72 ++++++++++++-------
>  2 files changed, 54 insertions(+), 28 deletions(-)
> 
> diff --git a/drivers/media/platform/Kconfig b/drivers/media/platform/Kconfig
> index a3cb104956d5..98eb62e49ec2 100644
> --- a/drivers/media/platform/Kconfig
> +++ b/drivers/media/platform/Kconfig
> @@ -253,14 +253,16 @@ config VIDEO_MEDIATEK_VCODEC
>  	depends on MTK_IOMMU || COMPILE_TEST
>  	depends on VIDEO_DEV && VIDEO_V4L2
>  	depends on ARCH_MEDIATEK || COMPILE_TEST
> +	depends on VIDEO_MEDIATEK_VPU || MTK_SCP

Close, but no cigar.

If VIDEO_MEDIATEK_VPU=y and MTK_SCP=m, then VIDEO_MEDIATEK_VCODEC can be configured
to y, and then it won't be able to find the scp_ functions.

To be honest, I'm not sure how to solve this.

Regards,

	Hans

>  	select VIDEOBUF2_DMA_CONTIG
>  	select V4L2_MEM2MEM_DEV
> -	select VIDEO_MEDIATEK_VPU
> -	select MTK_SCP
>  	help
>  	    Mediatek video codec driver provides HW capability to
> -	    encode and decode in a range of video formats
> -	    This driver rely on VPU driver to communicate with VPU.
> +	    encode and decode in a range of video formats on MT8173
> +	    and MT8183.
> +
> +	    Note that support for MT8173 requires VIDEO_MEDIATEK_VPU to
> +	    also be selected. Support for MT8183 depends on MTK_SCP.
>  
>  	    To compile this driver as modules, choose M here: the
>  	    modules will be called mtk-vcodec-dec and mtk-vcodec-enc.
> diff --git a/drivers/media/platform/mtk-vcodec/mtk_vcodec_fw.c b/drivers/media/platform/mtk-vcodec/mtk_vcodec_fw.c
> index 6c2a2568d844..23a80027a8fb 100644
> --- a/drivers/media/platform/mtk-vcodec/mtk_vcodec_fw.c
> +++ b/drivers/media/platform/mtk-vcodec/mtk_vcodec_fw.c
> @@ -13,6 +13,7 @@ struct mtk_vcodec_fw_ops {
>  			    mtk_vcodec_ipi_handler handler, const char *name, void *priv);
>  	int (*ipi_send)(struct mtk_vcodec_fw *fw, int id, void *buf,
>  			unsigned int len, unsigned int wait);
> +	void (*release)(struct mtk_vcodec_fw *fw);
>  };
>  
>  struct mtk_vcodec_fw {
> @@ -22,6 +23,8 @@ struct mtk_vcodec_fw {
>  	struct mtk_scp *scp;
>  };
>  
> +#if IS_ENABLED(CONFIG_VIDEO_MEDIATEK_VPU)
> +
>  static int mtk_vcodec_vpu_load_firmware(struct mtk_vcodec_fw *fw)
>  {
>  	return vpu_load_firmware(fw->pdev);
> @@ -64,6 +67,27 @@ static int mtk_vcodec_vpu_ipi_send(struct mtk_vcodec_fw *fw, int id, void *buf,
>  	return vpu_ipi_send(fw->pdev, id, buf, len);
>  }
>  
> +static void mtk_vcodec_vpu_release(struct mtk_vcodec_fw *fw)
> +{
> +	put_device(&fw->pdev->dev);
> +}
> +
> +static void mtk_vcodec_vpu_reset_handler(void *priv)
> +{
> +	struct mtk_vcodec_dev *dev = priv;
> +	struct mtk_vcodec_ctx *ctx;
> +
> +	mtk_v4l2_err("Watchdog timeout!!");
> +
> +	mutex_lock(&dev->dev_mutex);
> +	list_for_each_entry(ctx, &dev->ctx_list, list) {
> +		ctx->state = MTK_STATE_ABORT;
> +		mtk_v4l2_debug(0, "[%d] Change to state MTK_STATE_ABORT",
> +			       ctx->id);
> +	}
> +	mutex_unlock(&dev->dev_mutex);
> +}
> +
>  static const struct mtk_vcodec_fw_ops mtk_vcodec_vpu_msg = {
>  	.load_firmware = mtk_vcodec_vpu_load_firmware,
>  	.get_vdec_capa = mtk_vcodec_vpu_get_vdec_capa,
> @@ -71,8 +95,13 @@ static const struct mtk_vcodec_fw_ops mtk_vcodec_vpu_msg = {
>  	.map_dm_addr = mtk_vcodec_vpu_map_dm_addr,
>  	.ipi_register = mtk_vcodec_vpu_set_ipi_register,
>  	.ipi_send = mtk_vcodec_vpu_ipi_send,
> +	.release = mtk_vcodec_vpu_release,
>  };
>  
> +#endif  /* IS_ENABLED(CONFIG_VIDEO_MEDIATEK_VPU) */
> +
> +#if IS_ENABLED(CONFIG_MTK_SCP)
> +
>  static int mtk_vcodec_scp_load_firmware(struct mtk_vcodec_fw *fw)
>  {
>  	return rproc_boot(scp_get_rproc(fw->scp));
> @@ -107,6 +136,11 @@ static int mtk_vcodec_scp_ipi_send(struct mtk_vcodec_fw *fw, int id, void *buf,
>  	return scp_ipi_send(fw->scp, id, buf, len, wait);
>  }
>  
> +static void mtk_vcodec_scp_release(struct mtk_vcodec_fw *fw)
> +{
> +	scp_put(fw->scp);
> +}
> +
>  static const struct mtk_vcodec_fw_ops mtk_vcodec_rproc_msg = {
>  	.load_firmware = mtk_vcodec_scp_load_firmware,
>  	.get_vdec_capa = mtk_vcodec_scp_get_vdec_capa,
> @@ -114,23 +148,10 @@ static const struct mtk_vcodec_fw_ops mtk_vcodec_rproc_msg = {
>  	.map_dm_addr = mtk_vcodec_vpu_scp_dm_addr,
>  	.ipi_register = mtk_vcodec_scp_set_ipi_register,
>  	.ipi_send = mtk_vcodec_scp_ipi_send,
> +	.release = mtk_vcodec_scp_release,
>  };
>  
> -static void mtk_vcodec_reset_handler(void *priv)
> -{
> -	struct mtk_vcodec_dev *dev = priv;
> -	struct mtk_vcodec_ctx *ctx;
> -
> -	mtk_v4l2_err("Watchdog timeout!!");
> -
> -	mutex_lock(&dev->dev_mutex);
> -	list_for_each_entry(ctx, &dev->ctx_list, list) {
> -		ctx->state = MTK_STATE_ABORT;
> -		mtk_v4l2_debug(0, "[%d] Change to state MTK_STATE_ABORT",
> -			       ctx->id);
> -	}
> -	mutex_unlock(&dev->dev_mutex);
> -}
> +#endif  /* IS_ENABLED(CONFIG_MTK_SCP) */
>  
>  struct mtk_vcodec_fw *mtk_vcodec_fw_select(struct mtk_vcodec_dev *dev,
>  					   enum mtk_vcodec_fw_type type,
> @@ -143,16 +164,22 @@ struct mtk_vcodec_fw *mtk_vcodec_fw_select(struct mtk_vcodec_dev *dev,
>  
>  	switch (type) {
>  	case VPU:
> +#if IS_ENABLED(CONFIG_VIDEO_MEDIATEK_VPU)
>  		ops = &mtk_vcodec_vpu_msg;
>  		fw_pdev = vpu_get_plat_device(dev->plat_dev);
>  		if (!fw_pdev) {
>  			mtk_v4l2_err("firmware device is not ready");
>  			return ERR_PTR(-EINVAL);
>  		}
> -		vpu_wdt_reg_handler(fw_pdev, mtk_vcodec_reset_handler,
> +		vpu_wdt_reg_handler(fw_pdev, mtk_vcodec_vpu_reset_handler,
>  				    dev, rst_id);
>  		break;
> +#else
> +		mtk_v4l2_err("no VPU support in this kernel");
> +		return ERR_PTR(-ENODEV);
> +#endif
>  	case SCP:
> +#if IS_ENABLED(CONFIG_MTK_SCP)
>  		ops = &mtk_vcodec_rproc_msg;
>  		scp = scp_get(dev->plat_dev);
>  		if (!scp) {
> @@ -160,6 +187,10 @@ struct mtk_vcodec_fw *mtk_vcodec_fw_select(struct mtk_vcodec_dev *dev,
>  			return ERR_PTR(-EPROBE_DEFER);
>  		}
>  		break;
> +#else
> +		mtk_v4l2_err("no SCP support in this kernel");
> +		return ERR_PTR(-ENODEV);
> +#endif
>  	default:
>  		mtk_v4l2_err("invalid vcodec fw type");
>  		return ERR_PTR(-EINVAL);
> @@ -180,14 +211,7 @@ EXPORT_SYMBOL_GPL(mtk_vcodec_fw_select);
>  
>  void mtk_vcodec_fw_release(struct mtk_vcodec_fw *fw)
>  {
> -	switch (fw->type) {
> -	case VPU:
> -		put_device(&fw->pdev->dev);
> -		break;
> -	case SCP:
> -		scp_put(fw->scp);
> -		break;
> -	}
> +	fw->ops->release(fw);
>  }
>  EXPORT_SYMBOL_GPL(mtk_vcodec_fw_release);
>  
>