Re: [PATCH v2 1/2] drm/komeda: Update the chip identify

[Mihail Atanassov <Mihail.Atanassov@arm.com>]

On Thursday, 21 November 2019 08:17:39 GMT james qian wang (Arm Technology China) wrote:
> 1. Drop komeda-CORE product id comparison and put it into the d71_identify
> 2. Update pipeline node DT-binding:
>    (a). Skip the needless pipeline DT node.
>    (b). Return fail if the essential pipeline DT node is missing.
> 
> With these changes, for one family chips no need to change the DT.
> 
> v2: Rebase
> 
> Signed-off-by: James Qian Wang (Arm Technology China) <james.qian.wang@arm.com>
> ---
>  .../gpu/drm/arm/display/komeda/d71/d71_dev.c  | 27 +++++++--
>  .../gpu/drm/arm/display/komeda/komeda_dev.c   | 60 ++++++++++---------
>  .../gpu/drm/arm/display/komeda/komeda_dev.h   | 14 +----
>  .../gpu/drm/arm/display/komeda/komeda_drv.c   |  9 +--
>  4 files changed, 58 insertions(+), 52 deletions(-)
> 
> diff --git a/drivers/gpu/drm/arm/display/komeda/d71/d71_dev.c b/drivers/gpu/drm/arm/display/komeda/d71/d71_dev.c
> index 822b23a1ce75..9b3bf353b6cc 100644
> --- a/drivers/gpu/drm/arm/display/komeda/d71/d71_dev.c
> +++ b/drivers/gpu/drm/arm/display/komeda/d71/d71_dev.c
> @@ -594,10 +594,27 @@ static const struct komeda_dev_funcs d71_chip_funcs = {
>  const struct komeda_dev_funcs *
>  d71_identify(u32 __iomem *reg_base, struct komeda_chip_info *chip)
>  {
> -	chip->arch_id	= malidp_read32(reg_base, GLB_ARCH_ID);
> -	chip->core_id	= malidp_read32(reg_base, GLB_CORE_ID);
> -	chip->core_info	= malidp_read32(reg_base, GLB_CORE_INFO);
> -	chip->bus_width	= D71_BUS_WIDTH_16_BYTES;
> +	const struct komeda_dev_funcs *funcs;
> +	u32 product_id;
>  
> -	return &d71_chip_funcs;
> +	chip->core_id = malidp_read32(reg_base, GLB_CORE_ID);
> +
> +	product_id = MALIDP_CORE_ID_PRODUCT_ID(chip->core_id);
> +
> +	switch (product_id) {
> +	case MALIDP_D71_PRODUCT_ID:
> +		funcs = &d71_chip_funcs;
> +		break;
> +	default:
> +		funcs = NULL;

[bikeshed] I'd just 'return NULL;' after printing the error...

> +		DRM_ERROR("Unsupported product: 0x%x\n", product_id);
> +	}
> +
> +	if (funcs) {

... and save myself the branch and indent level here.

> +		chip->arch_id	= malidp_read32(reg_base, GLB_ARCH_ID);
> +		chip->core_info	= malidp_read32(reg_base, GLB_CORE_INFO);
> +		chip->bus_width	= D71_BUS_WIDTH_16_BYTES;
> +	}
> +
> +	return funcs;
>  }
> diff --git a/drivers/gpu/drm/arm/display/komeda/komeda_dev.c b/drivers/gpu/drm/arm/display/komeda/komeda_dev.c
> index 4dd4699d4e3d..8e0bce46555b 100644
> --- a/drivers/gpu/drm/arm/display/komeda/komeda_dev.c
> +++ b/drivers/gpu/drm/arm/display/komeda/komeda_dev.c
> @@ -116,22 +116,14 @@ static struct attribute_group komeda_sysfs_attr_group = {
>  	.attrs = komeda_sysfs_entries,
>  };
>  
> -static int komeda_parse_pipe_dt(struct komeda_dev *mdev, struct device_node *np)
> +static int komeda_parse_pipe_dt(struct komeda_pipeline *pipe)
>  {
> -	struct komeda_pipeline *pipe;
> +	struct device_node *np = pipe->of_node;
>  	struct clk *clk;
> -	u32 pipe_id;
> -	int ret = 0;
> -
> -	ret = of_property_read_u32(np, "reg", &pipe_id);
> -	if (ret != 0 || pipe_id >= mdev->n_pipelines)
> -		return -EINVAL;
> -
> -	pipe = mdev->pipelines[pipe_id];
>  
>  	clk = of_clk_get_by_name(np, "pxclk");
>  	if (IS_ERR(clk)) {
> -		DRM_ERROR("get pxclk for pipeline %d failed!\n", pipe_id);
> +		DRM_ERROR("get pxclk for pipeline %d failed!\n", pipe->id);
>  		return PTR_ERR(clk);
>  	}
>  	pipe->pxlclk = clk;
> @@ -145,7 +137,6 @@ static int komeda_parse_pipe_dt(struct komeda_dev *mdev, struct device_node *np)
>  		of_graph_get_port_by_id(np, KOMEDA_OF_PORT_OUTPUT);
>  
>  	pipe->dual_link = pipe->of_output_links[0] && pipe->of_output_links[1];
> -	pipe->of_node = of_node_get(np);
>  
>  	return 0;
>  }
> @@ -154,7 +145,9 @@ static int komeda_parse_dt(struct device *dev, struct komeda_dev *mdev)
>  {
>  	struct platform_device *pdev = to_platform_device(dev);
>  	struct device_node *child, *np = dev->of_node;
> -	int ret;
> +	struct komeda_pipeline *pipe;
> +	u32 pipe_id = U32_MAX;
> +	int ret = -1;
>  
>  	mdev->irq  = platform_get_irq(pdev, 0);
>  	if (mdev->irq < 0) {
> @@ -169,31 +162,44 @@ static int komeda_parse_dt(struct device *dev, struct komeda_dev *mdev)
>  	ret = 0;
>  
>  	for_each_available_child_of_node(np, child) {
> -		if (of_node_cmp(child->name, "pipeline") == 0) {
> -			ret = komeda_parse_pipe_dt(mdev, child);
> -			if (ret) {
> -				DRM_ERROR("parse pipeline dt error!\n");
> -				of_node_put(child);
> -				break;
> +		if (of_node_name_eq(child, "pipeline")) {
> +			of_property_read_u32(child, "reg", &pipe_id);
> +			if (pipe_id >= mdev->n_pipelines) {
> +				DRM_WARN("Skip the redundant DT node: pipeline-%u.\n",
> +					 pipe_id);
> +				continue;
>  			}
> +			mdev->pipelines[pipe_id]->of_node = of_node_get(child);
>  		}
>  	}
>  
> +	for (pipe_id = 0; pipe_id < mdev->n_pipelines; pipe_id++) {
> +		pipe = mdev->pipelines[pipe_id];
> +
> +		if (!pipe->of_node) {
> +			DRM_ERROR("Omit DT node for pipeline-%d.\n", pipe->id);

[nit] "Omit DT node" doesn't sound like an error condition. How about:

"pipeline-%d doesn't have a DT node."

> +			return -EINVAL;
> +		}
> +		ret = komeda_parse_pipe_dt(pipe);
> +		if (ret)
> +			return ret;
> +	}
> +
>  	mdev->side_by_side = !of_property_read_u32(np, "side_by_side_master",

Looks like this isn't based off drm-misc-next, and is instead based on
https://patchwork.freedesktop.org/patch/341867/

>  						   &mdev->side_by_side_master);
>  
> -	return ret;
> +	return 0;
>  }
>  
>  struct komeda_dev *komeda_dev_create(struct device *dev)
>  {
>  	struct platform_device *pdev = to_platform_device(dev);
> -	const struct komeda_product_data *product;
> +	komeda_identify_func komeda_identify;
>  	struct komeda_dev *mdev;
>  	int err = 0;
>  
> -	product = of_device_get_match_data(dev);
> -	if (!product)
> +	komeda_identify = of_device_get_match_data(dev);
> +	if (!komeda_identify)
>  		return ERR_PTR(-ENODEV);
>  
>  	mdev = devm_kzalloc(dev, sizeof(*mdev), GFP_KERNEL);
> @@ -221,11 +227,9 @@ struct komeda_dev *komeda_dev_create(struct device *dev)
>  
>  	clk_prepare_enable(mdev->aclk);
>  
> -	mdev->funcs = product->identify(mdev->reg_base, &mdev->chip);
> -	if (!komeda_product_match(mdev, product->product_id)) {
> -		DRM_ERROR("DT configured %x mismatch with real HW %x.\n",
> -			  product->product_id,
> -			  MALIDP_CORE_ID_PRODUCT_ID(mdev->chip.core_id));
> +	mdev->funcs = komeda_identify(mdev->reg_base, &mdev->chip);
> +	if (!mdev->funcs) {
> +		DRM_ERROR("Failed to identify the HW.\n");
>  		err = -ENODEV;
>  		goto disable_clk;
>  	}
> diff --git a/drivers/gpu/drm/arm/display/komeda/komeda_dev.h b/drivers/gpu/drm/arm/display/komeda/komeda_dev.h
> index 471604b42431..dacdb00153e9 100644
> --- a/drivers/gpu/drm/arm/display/komeda/komeda_dev.h
> +++ b/drivers/gpu/drm/arm/display/komeda/komeda_dev.h
> @@ -58,11 +58,6 @@
>  			    | KOMEDA_EVENT_MODE \
>  			    )
>  
> -/* malidp device id */
> -enum {
> -	MALI_D71 = 0,
> -};
> -
>  /* pipeline DT ports */
>  enum {
>  	KOMEDA_OF_PORT_OUTPUT		= 0,
> @@ -76,12 +71,6 @@ struct komeda_chip_info {
>  	u32 bus_width;
>  };
>  
> -struct komeda_product_data {
> -	u32 product_id;
> -	const struct komeda_dev_funcs *(*identify)(u32 __iomem *reg,
> -					     struct komeda_chip_info *info);
> -};
> -
>  struct komeda_dev;
>  
>  struct komeda_events {
> @@ -243,6 +232,9 @@ komeda_product_match(struct komeda_dev *mdev, u32 target)
>  	return MALIDP_CORE_ID_PRODUCT_ID(mdev->chip.core_id) == target;
>  }
>  
> +typedef const struct komeda_dev_funcs *
> +(*komeda_identify_func)(u32 __iomem *reg, struct komeda_chip_info *chip);
> +
>  const struct komeda_dev_funcs *
>  d71_identify(u32 __iomem *reg, struct komeda_chip_info *chip);
>  
> diff --git a/drivers/gpu/drm/arm/display/komeda/komeda_drv.c b/drivers/gpu/drm/arm/display/komeda/komeda_drv.c
> index d6c2222c5d33..b7a1097c45c4 100644
> --- a/drivers/gpu/drm/arm/display/komeda/komeda_drv.c
> +++ b/drivers/gpu/drm/arm/display/komeda/komeda_drv.c
> @@ -123,15 +123,8 @@ static int komeda_platform_remove(struct platform_device *pdev)
>  	return 0;
>  }
>  
> -static const struct komeda_product_data komeda_products[] = {
> -	[MALI_D71] = {
> -		.product_id = MALIDP_D71_PRODUCT_ID,
> -		.identify = d71_identify,
> -	},
> -};
> -
>  static const struct of_device_id komeda_of_match[] = {
> -	{ .compatible = "arm,mali-d71", .data = &komeda_products[MALI_D71], },
> +	{ .compatible = "arm,mali-d71", .data = d71_identify, },
>  	{},
>  };
>  
> 

With the above two fixed (i.e. feel free to ignore the bikeshed),
Reviewed-by: Mihail Atanassov <mihail.atanassov@arm.com>

-- 
Mihail