efi/gop: Add an option to list out the available GOP modes

Add video=efifb:list option to list the modes that are available.

Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200518190716.751506-20-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

efi/gop: Use efi_err for error messages

Use efi_err instead of bare efi_printk for error messages.

Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200430182843.2510180-6-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

efi/libstub: Add a helper function to split 64-bit values

In several places 64-bit values need to be split up into two 32-bit
fields, in order to be backward-compatible with the old 32-bit ABIs.

Instead of open-coding this, add a helper function to set a 64-bit value
as two 32-bit fields.

Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200430182843.2510180-3-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

efi: Kill __efistub_global

Now that both arm and x86 are using the linker script to place the EFI
stub's global variables in the correct section, remove __efistub_global.

Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Link: https://lore.kernel.org/r/20200416151227.3360778-4-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

efi/gop: Allow automatically choosing the best mode

Add the ability to automatically pick the highest resolution video mode
(defined as the product of vertical and horizontal resolution) by using
a command-line argument of the form
video=efifb:auto

If there are multiple modes with the highest resolution, pick one with
the highest color depth.

Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200328160601.378299-2-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

efi/gop: Allow specifying depth as well as resolution

Extend the video mode argument to handle an optional color depth
specification of the form
video=efifb:<xres>x<yres>[-(rgb|bgr|<bpp>)]

Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200320020028.1936003-14-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

efi/gop: Allow specifying mode by <xres>x<yres>

Add the ability to choose a video mode using a command-line argument of
the form
video=efifb:<xres>x<yres>

Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200320020028.1936003-13-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

efi/gop: Allow specifying mode number on command line

Add the ability to choose a video mode for the selected gop by using a
command-line argument of the form
video=efifb:mode=<n>

Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200320020028.1936003-12-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

efi/gop: Remove unreachable code from setup_pixel_info

pixel_format must be one of
PIXEL_RGB_RESERVED_8BIT_PER_COLOR
PIXEL_BGR_RESERVED_8BIT_PER_COLOR
PIXEL_BIT_MASK
since we skip PIXEL_BLT_ONLY when finding a gop.

Remove the redundant code and add another check in find_gop to skip any
pixel formats that we don't know about, in case a later version of the
UEFI spec adds one.

Reformat the code a little.

Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200320020028.1936003-10-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

efi/gop: Use helper macros for find_bits

Use the __ffs/__fls macros to calculate the position and size of the
mask.

Correct type of mask to u32 instead of unsigned long.

Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200320020028.1936003-9-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

efi/gop: Use helper macros for populating lfb_base

Use the lower/upper_32_bits macros from kernel.h to initialize
si->lfb_base and si->ext_lfb_base.

Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200320020028.1936003-8-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

efi/gop: Move variable declarations into loop block

Declare the variables inside the block where they're used.

Get rid of a couple of redundant initializers.

Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200320020028.1936003-7-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

efi/gop: Slightly re-arrange logic of find_gop

Small cleanup to get rid of conout_found.

Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200320020028.1936003-6-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

efi/gop: Factor out locating the gop into a function

Move the loop to find a gop into its own function.

Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200320020028.1936003-5-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

efi/gop: Get mode information outside the loop

Move extraction of the mode information parameters outside the loop to
find the gop, and eliminate some redundant variables.

Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200320020028.1936003-4-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

efi/gop: Move check for framebuffer before con_out

If the gop doesn't have a framebuffer, there's no point in checking for
con_out support.

Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200320020028.1936003-3-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

efi/gop: Remove redundant current_fb_base

current_fb_base isn't used for anything except assigning to fb_base if
we locate a suitable gop.

Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20200320020028.1936003-2-nivedita@alum.mit.edu
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

efi/libstub: Rename efi_call_early/_runtime macros to be more intuitive

The macros efi_call_early and efi_call_runtime are used to call EFI
boot services and runtime services, respectively. However, the naming
is confusing, given that the early vs runtime distinction may suggest
that these are used for calling the same set of services either early
or late (== at runtime), while in reality, the sets of services they
can be used with are completely disjoint, and efi_call_runtime is also
only usable in 'early' code.

So do a global sweep to replace all occurrences with efi_bs_call or
efi_rt_call, respectively, where BS and RT match the idiom used by
the UEFI spec to refer to boot time or runtime services.

While at it, use 'func' as the macro parameter name for the function
pointers, which is less likely to collide and cause weird build errors.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Cc: Arvind Sankar <nivedita@alum.mit.edu>
Cc: Borislav Petkov <bp@alien8.de>
Cc: James Morse <james.morse@arm.com>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: https://lkml.kernel.org/r/20191224151025.32482-24-ardb@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

efi/libstub: Drop 'table' argument from efi_table_attr() macro

None of the definitions of the efi_table_attr() still refer to
their 'table' argument so let's get rid of it entirely.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Cc: Arvind Sankar <nivedita@alum.mit.edu>
Cc: Borislav Petkov <bp@alien8.de>
Cc: James Morse <james.morse@arm.com>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: https://lkml.kernel.org/r/20191224151025.32482-23-ardb@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

efi/libstub: Remove 'sys_table_arg' from all function prototypes

We have a helper efi_system_table() that gives us the address of the
EFI system table in memory, so there is no longer point in passing
it around from each function to the next.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Cc: Arvind Sankar <nivedita@alum.mit.edu>
Cc: Borislav Petkov <bp@alien8.de>
Cc: James Morse <james.morse@arm.com>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: https://lkml.kernel.org/r/20191224151025.32482-20-ardb@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

efi/libstub: Get rid of 'sys_table_arg' macro parameter

The efi_call macros on ARM have a dependency on a variable 'sys_table_arg'
existing in the scope of the macro instantiation. Since this variable
always points to the same data structure, let's create a global getter
for it and use that instead.

Note that the use of a global variable with external linkage is avoided,
given the problems we had in the past with early processing of the GOT
tables.

While at it, drop the redundant casts in the efi_table_attr and
efi_call_proto macros.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Cc: Arvind Sankar <nivedita@alum.mit.edu>
Cc: Borislav Petkov <bp@alien8.de>
Cc: James Morse <james.morse@arm.com>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: https://lkml.kernel.org/r/20191224151025.32482-16-ardb@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

efi/libstub: Use a helper to iterate over a EFI handle array

Iterating over a EFI handle array is a bit finicky, since we have
to take mixed mode into account, where handles are only 32-bit
while the native efi_handle_t type is 64-bit.

So introduce a helper, and replace the various occurrences of
this pattern.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Cc: Arvind Sankar <nivedita@alum.mit.edu>
Cc: Borislav Petkov <bp@alien8.de>
Cc: James Morse <james.morse@arm.com>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: https://lkml.kernel.org/r/20191224151025.32482-8-ardb@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

efi/gop: Unify 32/64-bit functions

Use efi_table_attr macro to deal with 32/64-bit firmware using the same
source code.

Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: James Morse <james.morse@arm.com>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: https://lkml.kernel.org/r/20191224151025.32482-5-ardb@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

efi/gop: Convert GOP structures to typedef and clean up some types

Use typedef for the GOP structures, in anticipation of unifying
32/64-bit code. Also use more appropriate types in the non-bitness
specific structures for the framebuffer address and pointers.

Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: James Morse <james.morse@arm.com>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: https://lkml.kernel.org/r/20191224151025.32482-4-ardb@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

efi/gop: Fix memory leak in __gop_query32/64()

efi_graphics_output_protocol::query_mode() returns info in
callee-allocated memory which must be freed by the caller, which
we aren't doing.

We don't actually need to call query_mode() in order to obtain the
info for the current graphics mode, which is already there in
gop->mode->info, so just access it directly in the setup_gop32/64()
functions.

Also nothing uses the size of the info structure, so don't update the
passed-in size (which is the size of the gop_handle table in bytes)
unnecessarily.

Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Bhupesh Sharma <bhsharma@redhat.com>
Cc: Masayoshi Mizuma <m.mizuma@jp.fujitsu.com>
Cc: linux-efi@vger.kernel.org
Link: https://lkml.kernel.org/r/20191206165542.31469-5-ardb@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

efi/gop: Return EFI_SUCCESS if a usable GOP was found

If we've found a usable instance of the Graphics Output Protocol
(GOP) with a framebuffer, it is possible that one of the later EFI
calls fails while checking if any support console output. In this
case status may be an EFI error code even though we found a usable
GOP.

Fix this by explicitly return EFI_SUCCESS if a usable GOP has been
located.

Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Bhupesh Sharma <bhsharma@redhat.com>
Cc: Masayoshi Mizuma <m.mizuma@jp.fujitsu.com>
Cc: linux-efi@vger.kernel.org
Link: https://lkml.kernel.org/r/20191206165542.31469-4-ardb@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

efi/gop: Return EFI_NOT_FOUND if there are no usable GOPs

If we don't find a usable instance of the Graphics Output Protocol
(GOP) because none of them have a framebuffer (i.e. they were all
PIXEL_BLT_ONLY), but all the EFI calls succeeded, we will return
EFI_SUCCESS even though we didn't find a usable GOP.

Fix this by explicitly returning EFI_NOT_FOUND if no usable GOPs are
found, allowing the caller to probe for UGA instead.

Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Bhupesh Sharma <bhsharma@redhat.com>
Cc: Masayoshi Mizuma <m.mizuma@jp.fujitsu.com>
Cc: linux-efi@vger.kernel.org
Link: https://lkml.kernel.org/r/20191206165542.31469-3-ardb@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

efi: Replace GPL license boilerplate with SPDX headers

Replace all GPL license blurbs with an equivalent SPDX header (most
files are GPLv2, some are GPLv2+). While at it, drop some outdated
header changelogs as well.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Alexander Graf <agraf@suse.de>
Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Heinrich Schuchardt <xypron.glpk@gmx.de>
Cc: Jeffrey Hugo <jhugo@codeaurora.org>
Cc: Lee Jones <lee.jones@linaro.org>
Cc: Leif Lindholm <leif.lindholm@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Jones <pjones@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20190202094119.13230-7-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

efi/libstub: Skip GOP with PIXEL_BLT_ONLY format

The UEFI Specification permits Graphics Output Protocol (GOP) instances
without direct framebuffer access. This is indicated in the Mode structure
with a PixelFormat enumeration value of PIXEL_BLT_ONLY. Given that the
kernel does not know how to drive a Blt() only framebuffer (which is only
permitted before ExitBootServices() anyway), we should disregard such
framebuffers when looking for a GOP instance that is suitable for use as
the boot console.

So modify the EFI GOP initialization to not use a PIXEL_BLT_ONLY instance,
preventing attempts later in boot to use an invalid screen_info.lfb_base
address.

Signed-off-by: Eugene Cohen <eugene@hp.com>
[ Moved the Blt() only check into the loop and clarified that Blt() only GOPs are unusable by the kernel. ]
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: <stable@vger.kernel.org> # v4.7+
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: leif.lindholm@linaro.org
Cc: linux-efi@vger.kernel.org
Cc: lorenzo.pieralisi@arm.com
Fixes: 9822504c1fa5 ("efifb: Enable the efi-framebuffer platform driver ...")
Link: http://lkml.kernel.org/r/20170404152744.26687-2-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

efi/libstub: Move Graphics Output Protocol handling to generic code

The Graphics Output Protocol code executes in the stub, so create a generic
version based on the x86 version in libstub so that we can move other archs
to it in subsequent patches. The new source file gop.c is added to the
libstub build for all architectures, but only wired up for x86.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Borislav Petkov <bp@alien8.de>
Cc: David Herrmann <dh.herrmann@gmail.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Jones <pjones@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/1461614832-17633-18-git-send-email-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>