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Date:   Fri, 20 May 2022 18:32:11 +0200
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Subject: Re: [PATCH V11 09/22] LoongArch: Add boot and setup routines
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To:     Huacai Chen <chenhuacai@gmail.com>
Cc:     Ard Biesheuvel <ardb@kernel.org>,
        Huacai Chen <chenhuacai@loongson.cn>,
        Arnd Bergmann <arnd@arndb.de>,
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        Thomas Gleixner <tglx@linutronix.de>,
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        Xuefeng Li <lixuefeng@loongson.cn>,
        Yanteng Si <siyanteng@loongson.cn>,
        Guo Ren <guoren@kernel.org>, Xuerui Wang <kernel@xen0n.name>,
        Jiaxun Yang <jiaxun.yang@flygoat.com>,
        Stephen Rothwell <sfr@canb.auug.org.au>,
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From:   Javier Martinez Canillas <javierm@redhat.com>
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On 5/20/22 17:19, Huacai Chen wrote:
> Hi, Javier,

[snip]

>> Conversely, if the sysfb_init() is executed first then the platform device
>> will be registered and latter when the driver's init register the driver
>> this will match the already registered device.
> Yes, you are right, my consideration is too complex. The only real
> problem is a harmless error "efifb: a framebuffer is already
> registered" when both efifb and the native display driver are
> built-in.
>

But this shouldn't be a problem if you drop your register_gop_device() that
registers an "efi-framebuffer", since sysfb would either register a platform
device "simple-framebufer" or "efi-framebuffer", but never both. Those are
mutually exclusive.

I think what's happening now is that sysfb is registering a "simple-framebuffer"
but your register_gop_device() function is also registering an "efi-framebuffer".

-- 
Best regards,

Javier Martinez Canillas
Linux Engineering
Red Hat