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Message-ID: <79e07134-4f89-22dd-5a9c-3c8dfac50bf2@loongson.cn>
Date:   Sat, 10 Jun 2023 02:07:58 +0800
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Subject: Re: [PATCH v8 6/8] drm/etnaviv: add driver support for the PCI
 devices
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To:     Bjorn Helgaas <helgaas@kernel.org>
Cc:     Sui Jingfeng <15330273260@189.cn>, Li Yi <liyi@loongson.cn>,
        linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org,
        etnaviv@lists.freedesktop.org,
        Russell King <linux+etnaviv@armlinux.org.uk>,
        Bjorn Helgaas <bhelgaas@google.com>
References: <20230609175201.GA1253027@bhelgaas>
From:   Sui Jingfeng <suijingfeng@loongson.cn>
Organization: Loongson
In-Reply-To: <20230609175201.GA1253027@bhelgaas>
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Hi,

On 2023/6/10 01:52, Bjorn Helgaas wrote:
> On Fri, Jun 09, 2023 at 09:37:02AM +0800, Sui Jingfeng wrote:
>> On 2023/6/9 01:32, Bjorn Helgaas wrote:
>>> On Wed, Jun 07, 2023 at 06:55:49PM +0800, Sui Jingfeng wrote:
>>>> From: Sui Jingfeng <suijingfeng@loongson.cn>
>>>>
>>>> This patch adds PCI driver support on top of what we already have. Take
>>>> the GC1000 in LS7A1000/LS2K1000 as the first instance of the PCI device
>>>> driver. There is only one GPU core for the GC1000 in the LS7A1000 and
>>>> LS2K1000. Therefore, component frameworks can be avoided.
>>>> +	{PCI_VENDOR_ID_LOONGSON, 0x7a15, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0},
>>>> +	{PCI_VENDOR_ID_LOONGSON, 0x7a05, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0},
>>> PCI_VDEVICE()
>> This make it impossible to hook device-specific data in the future.
>>
>> But currently there no device specific data associated with the
>> 0x7a05 and 0x7a15,
>>
>> so it's acceptable for now. Thanks.
> Haha, ISTR having this conversation before, sorry for repeating it.
>
> Indeed, it's fine as-is.  But PCI_VDEVICE() actually *does* allow for
> vendor-specific data because it doesn't include the data element,
> which defaults to zero if you don't specify it.
>
> So for example, drivers/net/ethernet/realtek/r8169_main.c has this:
>
>    { PCI_VDEVICE(REALTEK, 0x8129) },
>    { PCI_VDEVICE(REALTEK, 0x8136), RTL_CFG_NO_GBIT },
>
> where 0x8129 has no driver_data (it defaults to zero), but 0x8136
> does.

Yeah, I'm wrong.

PCI_VDEVICE macro end with two zero. (I thought it was three)

Thanks for the education.

With those lessons learned, I somewhat know how to create patch.

It should meet community's requirement before sending.

I'm too naive in the before.

Thanks a lot, really.

> Bjorn

-- 
Jingfeng