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Message-ID: <52751b55-ce34-f3a8-b3c0-4858ad984622@loongson.cn>
Date:   Wed, 21 Jun 2023 17:20:08 +0800
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Subject: Re: [PATCH v10 01/11] drm/etnaviv: Add a dedicated function to
 register an irq handler
Content-Language: en-US
To:     Lucas Stach <l.stach@pengutronix.de>,
        Sui Jingfeng <18949883232@163.com>,
        Russell King <linux+etnaviv@armlinux.org.uk>,
        Christian Gmeiner <christian.gmeiner@gmail.com>,
        David Airlie <airlied@gmail.com>,
        Daniel Vetter <daniel@ffwll.ch>
Cc:     linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org,
        etnaviv@lists.freedesktop.org,
        Philipp Zabel <p.zabel@pengutronix.de>,
        Bjorn Helgaas <bhelgaas@google.com>
References: <20230620094716.2231414-1-18949883232@163.com>
 <20230620094716.2231414-2-18949883232@163.com>
 <77f62814f98dd2728a1e4747f0db6b2a3cfa2c11.camel@pengutronix.de>
From:   Sui Jingfeng <suijingfeng@loongson.cn>
Organization: Loongson
In-Reply-To: <77f62814f98dd2728a1e4747f0db6b2a3cfa2c11.camel@pengutronix.de>
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Precedence: bulk

Hi,

On 2023/6/21 17:07, Lucas Stach wrote:
> Am Dienstag, dem 20.06.2023 um 17:47 +0800 schrieb Sui Jingfeng:
>> From: Sui Jingfeng <suijingfeng@loongson.cn>
>>
>> Because getting IRQ from a device is platform-dependent, PCI devices have
>> different methods for getting an IRQ. This patch is a preparation to extend
>> this driver for supporting the PCI devices.
>>
>> Cc: Lucas Stach <l.stach@pengutronix.de>
>> Cc: Christian Gmeiner <christian.gmeiner@gmail.com>
>> Cc: Philipp Zabel <p.zabel@pengutronix.de>
>> Cc: Bjorn Helgaas <bhelgaas@google.com>
>> Cc: Daniel Vetter <daniel@ffwll.ch>
>> Signed-off-by: Sui Jingfeng <suijingfeng@loongson.cn>
>> ---
>>   drivers/gpu/drm/etnaviv/etnaviv_gpu.c | 32 +++++++++++++++++++--------
>>   1 file changed, 23 insertions(+), 9 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/etnaviv/etnaviv_gpu.c b/drivers/gpu/drm/etnaviv/etnaviv_gpu.c
>> index de8c9894967c..a03e81337d8f 100644
>> --- a/drivers/gpu/drm/etnaviv/etnaviv_gpu.c
>> +++ b/drivers/gpu/drm/etnaviv/etnaviv_gpu.c
>> @@ -1817,6 +1817,27 @@ static const struct of_device_id etnaviv_gpu_match[] = {
>>   };
>>   MODULE_DEVICE_TABLE(of, etnaviv_gpu_match);
>>   
>> +static int etnaviv_gpu_register_irq(struct etnaviv_gpu *gpu, int irq)
>> +{
>> +	struct device *dev = gpu->dev;
>> +	int err;
>> +
>> +	if (irq < 0)
>> +		return irq;
>> +
>> +	err = devm_request_irq(dev, irq, irq_handler, 0, dev_name(dev), gpu);
>> +	if (err) {
>> +		dev_err(dev, "failed to request irq %u: %d\n", irq, err);
>> +		return err;
>> +	}
>> +
>> +	gpu->irq = irq;
>> +
>> +	dev_info(dev, "irq(%d) handler registered\n", irq);
> There is no reason to put this into the kernel log.

I want to see the IRQ of the device when debugging,

etnaviv actually print very less.

This serve as a minimal signal  to us the etnaviv_gpu_register_irq() 
function is successful at driver load time.

>   It's no different
> than other resources to the driver and we don't log each one of those
> either.
>
> In fact I don't see any reason for this change in the first place.
> Effectively you are moving a single function call into a new function,
> which doesn't seem like an improvement.

This is to make the patch easy to review, each patch is only introduce a 
small function,

which is paving the way for we introducing the PCI device driver.

Otherwise when we introducing the PCI device driver, the patch is looks 
ugly,

It is difficult to review.

> Regards,
> Lucas
>
>> +
>> +	return 0;
>> +}
>> +
>>   static int etnaviv_gpu_platform_probe(struct platform_device *pdev)
>>   {
>>   	struct device *dev = &pdev->dev;
>> @@ -1837,16 +1858,9 @@ static int etnaviv_gpu_platform_probe(struct platform_device *pdev)
>>   		return PTR_ERR(gpu->mmio);
>>   
>>   	/* Get Interrupt: */
>> -	gpu->irq = platform_get_irq(pdev, 0);
>> -	if (gpu->irq < 0)
>> -		return gpu->irq;
>> -
>> -	err = devm_request_irq(&pdev->dev, gpu->irq, irq_handler, 0,
>> -			       dev_name(gpu->dev), gpu);
>> -	if (err) {
>> -		dev_err(dev, "failed to request IRQ%u: %d\n", gpu->irq, err);
>> +	err = etnaviv_gpu_register_irq(gpu, platform_get_irq(pdev, 0));
>> +	if (err)
>>   		return err;
>> -	}
>>   
>>   	/* Get Clocks: */
>>   	gpu->clk_reg = devm_clk_get_optional(&pdev->dev, "reg");

-- 
Jingfeng