> -----Original Message----- > From: Arindam Nath <anath....@gmail.com> On Behalf Of Arindam Nath > Sent: Wednesday, June 27, 2018 8:26 PM > To: grub-devel@gnu.org > Cc: Nath, Arindam <arindam.n...@amd.com> > Subject: [PATCH] i386/linux: add support for ext_lfb_base > > The EFI Graphics Output Protocol can return a 64-bit > linear frame buffer address in some firmware/BIOS > implementations. We currently only store the lower > 32-bits in the lfb_base. This will eventually be > passed to Linux kernel and the efifb driver will > incorrectly interpret the framebuffer address as > 32-bit address. > > The Linux kernel has already added support to handle > 64-bit linear framebuffer address in the efifb driver > since quite some time now. > > This patch adds the support for 64-bit linear frame > buffer address in GRUB to address the above mentioned > scenario. > > Signed-off-by: Arindam Nath <arindam.n...@amd.com> > --- > grub-core/loader/i386/linux.c | 2 ++ > include/grub/i386/linux.h | 5 ++++- > 2 files changed, 6 insertions(+), 1 deletion(-) > > diff --git a/grub-core/loader/i386/linux.c b/grub-core/loader/i386/linux.c > index 083f9417c..1644e8132 100644 > --- a/grub-core/loader/i386/linux.c > +++ b/grub-core/loader/i386/linux.c > @@ -306,6 +306,8 @@ grub_linux_setup_video (struct linux_kernel_params > *params) > params->lfb_line_len = mode_info.pitch; > > params->lfb_base = (grub_size_t) framebuffer; > + params->ext_lfb_base = (grub_size_t) (((grub_uint64_t)(grub_size_t) > framebuffer) >> 32); > + params->capabilities |= VIDEO_CAPABILITY_64BIT_BASE; > params->lfb_size = ALIGN_UP (params->lfb_line_len * params->lfb_height, > 65536); > > params->red_mask_size = mode_info.red_mask_size; > diff --git a/include/grub/i386/linux.h b/include/grub/i386/linux.h > index da0ca3b83..e3f91e7c0 100644 > --- a/include/grub/i386/linux.h > +++ b/include/grub/i386/linux.h > @@ -188,8 +188,11 @@ struct linux_kernel_params > grub_uint16_t lfb_pages; /* 32 */ > grub_uint16_t vesa_attrib; /* 34 */ > grub_uint32_t capabilities; /* 36 */ > +#define VIDEO_CAPABILITY_SKIP_QUIRKS (1 << 0) > +#define VIDEO_CAPABILITY_64BIT_BASE (1 << 1) /* Frame buffer base > is 64-bit */ > + grub_uint32_t ext_lfb_base; /* 3a */ > > - grub_uint8_t padding3[0x40 - 0x3a]; > + grub_uint8_t padding3[0x40 - 0x3e]; > > grub_uint16_t apm_version; /* 40 */ > grub_uint16_t apm_code_segment; /* 42 */ > -- > 2.17.1
Could you help review the changes? Thanks, Arindam _______________________________________________ Grub-devel mailing list Grub-devel@gnu.org https://lists.gnu.org/mailman/listinfo/grub-devel
