| Message ID | 1440763939-17027-1-git-send-email-matt@codeblueprint.co.uk (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Fri, Aug 28, 2015 at 01:12:19PM +0100, Matt Fleming wrote: > From: Matt Fleming <matt.fleming@intel.com> > > The EFI Graphics Output Protocol uses 64-bit frame buffer addresses > but these get truncated to 32-bit by the EFI boot stub when storing > the address in the 'lfb_base' field of 'struct screen_info'. > > Add a 'ext_lfb_base' field for the upper 32-bits of the frame buffer > address and set VIDEO_TYPE_CAPABILITY_64BIT_BASE when the field is > useable. > > It turns out that the reason no one has required this support so far > is that there's actually code in tianocore to "downgrade" PCI > resources that have option ROMs and 64-bit BARS from 64-bit to 32-bit > to cope with legacy option ROMs that can't handle 64-bit addresses. > The upshot is that basically all GOP devices in the wild use a 32-bit > frame buffer address. > > Still, it is possible to build firmware that uses a full 64-bit GOP > frame buffer address. Chad did, which led to him reporting this issue. > > Add support in anticipation of GOP devices using 64-bit addresses more > widely, and so that efifb works out of the box when that happens. > > Reported-by: Chad Page <chad.page@znyx.com> > Cc: Pete Hawkins <pete.hawkins@znyx.com> > Cc: Peter Jones <pjones@redhat.com> > Cc: Matthew Garrett <mjg59@srcf.ucam.org> > Signed-off-by: Matt Fleming <matt.fleming@intel.com> Looks good to me. Acked-by: Peter Jones <pjones@redhat.com>
On Fri, Aug 28, 2015 at 2:12 PM, Matt Fleming <matt@codeblueprint.co.uk> wrote: > --- a/arch/x86/boot/compressed/eboot.c > +++ b/arch/x86/boot/compressed/eboot.c > @@ -624,7 +624,7 @@ setup_pixel_info(struct screen_info *si, u32 pixels_per_scan_line, > static efi_status_t > __gop_query32(struct efi_graphics_output_protocol_32 *gop32, > struct efi_graphics_output_mode_info **info, > - unsigned long *size, u32 *fb_base) > + unsigned long *size, u64 *fb_base) phys_addr_t instead of u64? Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds -- To unsubscribe from this list: send the line "unsubscribe linux-fbdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Mon, 31 Aug, at 10:24:31PM, Geert Uytterhoeven wrote: > On Fri, Aug 28, 2015 at 2:12 PM, Matt Fleming <matt@codeblueprint.co.uk> wrote: > > --- a/arch/x86/boot/compressed/eboot.c > > +++ b/arch/x86/boot/compressed/eboot.c > > @@ -624,7 +624,7 @@ setup_pixel_info(struct screen_info *si, u32 pixels_per_scan_line, > > static efi_status_t > > __gop_query32(struct efi_graphics_output_protocol_32 *gop32, > > struct efi_graphics_output_mode_info **info, > > - unsigned long *size, u32 *fb_base) > > + unsigned long *size, u64 *fb_base) > > phys_addr_t instead of u64? I can see why you might think that, but no, phys_addr_t isn't the correct data type because your kernel config dictates whether that's u32 or u64. We're interacting with the firmware here and the frame buffer address is always u64, for both 32-bit and 64-bit firmware. It's defined that way in the UEFI spec. It's better to be explicit about these kinds of things, and use u64.
diff --git a/arch/x86/boot/compressed/eboot.c b/arch/x86/boot/compressed/eboot.c index 7d69afd8b6fa..43473bb86ac0 100644 --- a/arch/x86/boot/compressed/eboot.c +++ b/arch/x86/boot/compressed/eboot.c @@ -624,7 +624,7 @@ setup_pixel_info(struct screen_info *si, u32 pixels_per_scan_line, static efi_status_t __gop_query32(struct efi_graphics_output_protocol_32 *gop32, struct efi_graphics_output_mode_info **info, - unsigned long *size, u32 *fb_base) + unsigned long *size, u64 *fb_base) { struct efi_graphics_output_protocol_mode_32 *mode; efi_status_t status; @@ -650,7 +650,8 @@ setup_gop32(struct screen_info *si, efi_guid_t *proto, unsigned long nr_gops; u16 width, height; u32 pixels_per_scan_line; - u32 fb_base; + u32 ext_lfb_base; + u64 fb_base; struct efi_pixel_bitmask pixel_info; int pixel_format; efi_status_t status; @@ -713,6 +714,13 @@ setup_gop32(struct screen_info *si, efi_guid_t *proto, si->lfb_width = width; si->lfb_height = height; si->lfb_base = fb_base; + + ext_lfb_base = (u64)(unsigned long)fb_base >> 32; + if (ext_lfb_base) { + si->capabilities |= VIDEO_CAPABILITY_64BIT_BASE; + si->ext_lfb_base = ext_lfb_base; + } + si->pages = 1; setup_pixel_info(si, pixels_per_scan_line, pixel_info, pixel_format); @@ -727,7 +735,7 @@ out: static efi_status_t __gop_query64(struct efi_graphics_output_protocol_64 *gop64, struct efi_graphics_output_mode_info **info, - unsigned long *size, u32 *fb_base) + unsigned long *size, u64 *fb_base) { struct efi_graphics_output_protocol_mode_64 *mode; efi_status_t status; @@ -753,7 +761,8 @@ setup_gop64(struct screen_info *si, efi_guid_t *proto, unsigned long nr_gops; u16 width, height; u32 pixels_per_scan_line; - u32 fb_base; + u32 ext_lfb_base; + u64 fb_base; struct efi_pixel_bitmask pixel_info; int pixel_format; efi_status_t status; @@ -816,6 +825,13 @@ setup_gop64(struct screen_info *si, efi_guid_t *proto, si->lfb_width = width; si->lfb_height = height; si->lfb_base = fb_base; + + ext_lfb_base = (u64)(unsigned long)fb_base >> 32; + if (ext_lfb_base) { + si->capabilities |= VIDEO_CAPABILITY_64BIT_BASE; + si->ext_lfb_base = ext_lfb_base; + } + si->pages = 1; setup_pixel_info(si, pixels_per_scan_line, pixel_info, pixel_format); diff --git a/drivers/video/fbdev/efifb.c b/drivers/video/fbdev/efifb.c index 4bfff349b1fb..95d293b7445a 100644 --- a/drivers/video/fbdev/efifb.c +++ b/drivers/video/fbdev/efifb.c @@ -114,6 +114,20 @@ static int efifb_setup(char *options) return 0; } +static inline bool fb_base_is_valid(void) +{ + if (screen_info.lfb_base) + return true; + + if (!(screen_info.capabilities & VIDEO_CAPABILITY_64BIT_BASE)) + return false; + + if (screen_info.ext_lfb_base) + return true; + + return false; +} + static int efifb_probe(struct platform_device *dev) { struct fb_info *info; @@ -141,7 +155,7 @@ static int efifb_probe(struct platform_device *dev) screen_info.lfb_depth = 32; if (!screen_info.pages) screen_info.pages = 1; - if (!screen_info.lfb_base) { + if (!fb_base_is_valid()) { printk(KERN_DEBUG "efifb: invalid framebuffer address\n"); return -ENODEV; } @@ -160,6 +174,14 @@ static int efifb_probe(struct platform_device *dev) } efifb_fix.smem_start = screen_info.lfb_base; + + if (screen_info.capabilities & VIDEO_CAPABILITY_64BIT_BASE) { + u64 ext_lfb_base; + + ext_lfb_base = (u64)(unsigned long)screen_info.ext_lfb_base << 32; + efifb_fix.smem_start |= ext_lfb_base; + } + efifb_defined.bits_per_pixel = screen_info.lfb_depth; efifb_defined.xres = screen_info.lfb_width; efifb_defined.yres = screen_info.lfb_height; diff --git a/include/uapi/linux/screen_info.h b/include/uapi/linux/screen_info.h index 7530e7447620..8b8d39dfb67f 100644 --- a/include/uapi/linux/screen_info.h +++ b/include/uapi/linux/screen_info.h @@ -43,7 +43,8 @@ struct screen_info { __u16 pages; /* 0x32 */ __u16 vesa_attributes; /* 0x34 */ __u32 capabilities; /* 0x36 */ - __u8 _reserved[6]; /* 0x3a */ + __u32 ext_lfb_base; /* 0x3a */ + __u8 _reserved[2]; /* 0x3e */ } __attribute__((packed)); #define VIDEO_TYPE_MDA 0x10 /* Monochrome Text Display */ @@ -69,6 +70,6 @@ struct screen_info { #define VIDEO_FLAGS_NOCURSOR (1 << 0) /* The video mode has no cursor set */ #define VIDEO_CAPABILITY_SKIP_QUIRKS (1 << 0) - +#define VIDEO_CAPABILITY_64BIT_BASE (1 << 1) /* Frame buffer base is 64-bit */ #endif /* _UAPI_SCREEN_INFO_H */