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Date:   Tue, 27 Sep 2022 18:46:09 +0200
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Subject: Re: [PATCH V4 XDMA 2/2] dmaengine: xilinx: xdma: Add user logic
 interrupt support
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To:     Lizhi Hou <lizhi.hou@amd.com>, vkoul@kernel.org,
        dmaengine@vger.kernel.org, linux-kernel@vger.kernel.org,
        trix@redhat.com
Cc:     max.zhen@amd.com, sonal.santan@amd.com, larry.liu@amd.com,
        brian.xu@amd.com
References: <1663871905-60498-1-git-send-email-lizhi.hou@amd.com>
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From:   =?UTF-8?Q?Martin_T=c5=afma?= <tumic@gpxsee.org>
In-Reply-To: <64388266-1707-ee20-c3ab-edb67ada68dc@amd.com>
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On 27. 09. 22 18:28, Lizhi Hou wrote:

> Okay, I got the point. How about changing request/remove APIs to 
> enable/disable APIs as below
> 
>       xdma_enable_user_irq(struct platform_device *pdev, u32 
> user_irq_index, u32 *irq)
> 
>              user_irq_index: user logic interrupt wire index. (XDMA 
> driver determines how system IRQs are mapped to DMA channels and user 
> logic wires)
> 
>              irq: IRQ number returned for registering interrupt handler 
> (request_irq()) or passing to existing platform driver.
> 
>      xdma_disable_user_irq(struct platform_device *pdev, u32 
> user_irq_index)
> 
> Does this make sense to you?
> 

I think even the "irq" parameter in the enable function is surplus as 
the parent driver (the driver of the actual PCIe card) knows* what PCI 
irq he has to allocate without XDMA providing the number.

xdma_enable_user_irq(struct platform_device *pdev, u32 user_irq_index);
xdma_disable_user_irq(struct platform_device *pdev, u32 user_irq_index);

should be all that is needed.

M.

* something like:
pci_irq_vector((pdev), PCI_BAR_ID) + NUM_C2H_CHANNELS + NUM_H2C_CHANNELS
can be used from the PCIe driver