Re: [PATCH] x86/efi: earlyprintk - Add 64bit efi fb address support

From: Aaron Ma
Date: Wed Sep 12 2018 - 11:09:28 EST


On 09/12/2018 11:00 PM, Ard Biesheuvel wrote:
> On 8 September 2018 at 18:23, Aaron Ma <aaron.ma@xxxxxxxxxxxxx> wrote:
>> EFI GOP uses 64-bit frame buffer address in some BIOS.
>> Add 64bit address support in efi earlyprintk.
>>
>> Signed-off-by: Aaron Ma <aaron.ma@xxxxxxxxxxxxx>
>> ---
>> arch/x86/platform/efi/early_printk.c | 4 ++++
>> 1 file changed, 4 insertions(+)
>>
>> diff --git a/arch/x86/platform/efi/early_printk.c b/arch/x86/platform/efi/early_printk.c
>> index 5fdacb322ceb..c0ae25f59acd 100644
>> --- a/arch/x86/platform/efi/early_printk.c
>> +++ b/arch/x86/platform/efi/early_printk.c
>> @@ -32,6 +32,8 @@ static __init int early_efi_map_fb(void)
>> return 0;
>>
>> base = boot_params.screen_info.lfb_base;
>> + if (boot_params.screen_info.capabilities & VIDEO_CAPABILITY_64BIT_BASE)
>> + base |= (u64)boot_params.screen_info.ext_lfb_base << 32;
>> size = boot_params.screen_info.lfb_size;
>> efi_fb = ioremap(base, size);
>>
>> @@ -49,6 +51,8 @@ static __ref void *early_efi_map(unsigned long start, unsigned long len)
>> unsigned long base;
>>
>> base = boot_params.screen_info.lfb_base;
>> + if (boot_params.screen_info.capabilities & VIDEO_CAPABILITY_64BIT_BASE)
>> + base |= (u64)boot_params.screen_info.ext_lfb_base << 32;
>>
>> if (efi_fb)
>> return (efi_fb + start);
> Please fix this in a way that works on 32-bit x86/PAE as well (i.e.,
> use a suitable type for base)
>

Right, I will send a v2 patch.

Thanks,
Aaron