Re: [PATCH v8 05/11] remoteproc: mediatek: Extract remoteproc initialization flow

From: Mathieu Poirier <mathieu.poirier@linaro.org>
To: Tinghan Shen <tinghan.shen@mediatek.com>
Cc: Bjorn Andersson <andersson@kernel.org>,
	Rob Herring <robh+dt@kernel.org>,
	Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
	Matthias Brugger <matthias.bgg@gmail.com>,
	AngeloGioacchino Del Regno 
	<angelogioacchino.delregno@collabora.com>,
	linux-remoteproc@vger.kernel.org, devicetree@vger.kernel.org,
	linux-kernel@vger.kernel.org,
	linux-arm-kernel@lists.infradead.org,
	linux-mediatek@lists.infradead.org,
	Project_Global_Chrome_Upstream_Group@mediatek.com
Subject: Re: [PATCH v8 05/11] remoteproc: mediatek: Extract remoteproc initialization flow
Date: Wed, 15 Mar 2023 11:34:08 -0600	[thread overview]
Message-ID: <20230315173408.GA2357129@p14s> (raw)
In-Reply-To: <20230303083355.3378-6-tinghan.shen@mediatek.com>

Hi Shen,

On Fri, Mar 03, 2023 at 04:33:49PM +0800, Tinghan Shen wrote:
> This is the preparation for probing multi-core SCP. The remoteproc
> initialization flow is similar on cores and is reuesd to avoid

s/reuesd/reused

> redundant code.
> 
> The registers of config and l1tcm are shared for multi-core
> SCP. Reuse the mapped addresses for all cores.
> 
> Signed-off-by: Tinghan Shen <tinghan.shen@mediatek.com>
> Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
> ---
>  drivers/remoteproc/mtk_scp.c | 62 ++++++++++++++++++++++++------------
>  1 file changed, 42 insertions(+), 20 deletions(-)
> 
> diff --git a/drivers/remoteproc/mtk_scp.c b/drivers/remoteproc/mtk_scp.c
> index a3b9bc158cd9..bdb5d87eeaa3 100644
> --- a/drivers/remoteproc/mtk_scp.c
> +++ b/drivers/remoteproc/mtk_scp.c
> @@ -23,6 +23,13 @@
>  #define MAX_CODE_SIZE 0x500000
>  #define SECTION_NAME_IPI_BUFFER ".ipi_buffer"
>  
> +struct mtk_scp_of_regs {
> +	void __iomem *reg_base;
> +	void __iomem *l1tcm_base;
> +	size_t l1tcm_size;
> +	phys_addr_t l1tcm_phys;
> +};
> +
>  /**
>   * scp_get() - get a reference to SCP.
>   *
> @@ -855,7 +862,8 @@ static void scp_remove_rpmsg_subdev(struct mtk_scp *scp)
>  	}
>  }
>  
> -static int scp_probe(struct platform_device *pdev)
> +static int scp_rproc_init(struct platform_device *pdev,
> +			  struct mtk_scp_of_regs *of_regs)
>  {
>  	struct device *dev = &pdev->dev;
>  	struct device_node *np = dev->of_node;
> @@ -879,6 +887,11 @@ static int scp_probe(struct platform_device *pdev)
>  	scp->data = of_device_get_match_data(dev);
>  	platform_set_drvdata(pdev, scp);
>  
> +	scp->reg_base = of_regs->reg_base;
> +	scp->l1tcm_base = of_regs->l1tcm_base;
> +	scp->l1tcm_size = of_regs->l1tcm_size;
> +	scp->l1tcm_phys = of_regs->l1tcm_phys;
> +
>  	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "sram");
>  	scp->sram_base = devm_ioremap_resource(dev, res);
>  	if (IS_ERR(scp->sram_base))
> @@ -888,24 +901,6 @@ static int scp_probe(struct platform_device *pdev)
>  	scp->sram_size = resource_size(res);
>  	scp->sram_phys = res->start;
>  
> -	/* l1tcm is an optional memory region */
> -	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "l1tcm");
> -	scp->l1tcm_base = devm_ioremap_resource(dev, res);
> -	if (IS_ERR(scp->l1tcm_base)) {
> -		ret = PTR_ERR(scp->l1tcm_base);
> -		if (ret != -EINVAL) {
> -			return dev_err_probe(dev, ret, "Failed to map l1tcm memory\n");
> -		}
> -	} else {
> -		scp->l1tcm_size = resource_size(res);
> -		scp->l1tcm_phys = res->start;
> -	}
> -
> -	scp->reg_base = devm_platform_ioremap_resource_byname(pdev, "cfg");
> -	if (IS_ERR(scp->reg_base))
> -		return dev_err_probe(dev, PTR_ERR(scp->reg_base),
> -				     "Failed to parse and map cfg memory\n");
> -
>  	ret = scp->data->scp_clk_get(scp);
>  	if (ret)
>  		return ret;
> @@ -933,7 +928,6 @@ static int scp_probe(struct platform_device *pdev)
>  	ret = devm_request_threaded_irq(dev, platform_get_irq(pdev, 0), NULL,
>  					scp_irq_handler, IRQF_ONESHOT,
>  					pdev->name, scp);
> -

Spurious change

>  	if (ret) {
>  		dev_err(dev, "failed to request irq\n");
>  		goto remove_subdev;
> @@ -957,6 +951,34 @@ static int scp_probe(struct platform_device *pdev)
>  	return ret;
>  }
>  
> +static int scp_probe(struct platform_device *pdev)
> +{
> +	struct device *dev = &pdev->dev;
> +	struct resource *res;
> +	struct mtk_scp_of_regs scp_regs;
> +	int ret;
> +
> +	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "cfg");
> +	scp_regs.reg_base = devm_ioremap_resource(dev, res);
> +	if (IS_ERR(scp_regs.reg_base))
> +		return dev_err_probe(dev, PTR_ERR(scp_regs.reg_base),
> +				     "Failed to parse and map cfg memory\n");
> +
> +	/* l1tcm is an optional memory region */
> +	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "l1tcm");
> +	scp_regs.l1tcm_base = devm_ioremap_resource(dev, res);
> +	if (IS_ERR(scp_regs.l1tcm_base)) {
> +		ret = PTR_ERR(scp_regs.l1tcm_base);
> +		if (ret != -EINVAL)
> +			return dev_err_probe(dev, ret, "Failed to map l1tcm memory\n");
> +	} else {
> +		scp_regs.l1tcm_size = resource_size(res);
> +		scp_regs.l1tcm_phys = res->start;
> +	}

If l1tcm is not specified scp_regs::[l1tcm_size, l1tcm_phys] contains garbage
that is then communicated to scp_rproc_init().  It seems to be the case in the
original code as well.

More comments to come.

> +
> +	return scp_rproc_init(pdev, &scp_regs);
> +}
> +
>  static int scp_remove(struct platform_device *pdev)
>  {
>  	struct mtk_scp *scp = platform_get_drvdata(pdev);
> -- 
> 2.18.0
> 