efi/arm*/libstub: Wire up GOP protocol to 'struct screen_info'

This adds the code to the ARM and arm64 versions of the UEFI stub to
populate struct screen_info based on the information received from the
firmware via the GOP protocol.

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/1461614832-17633-23-git-send-email-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>

diff --git a/drivers/firmware/efi/libstub/arm-stub.c b/drivers/firmware/efi/libstub/arm-stub.c
index 128632508fc64f78c6fef66e05b45ec88be1f459..993aa56755f60afb929f90521485fd5fab335583 100644 (file)
--- a/drivers/firmware/efi/libstub/arm-stub.c
+++ b/drivers/firmware/efi/libstub/arm-stub.c
@@ -169,6 +169,25 @@ void efi_char16_printk(efi_system_table_t *sys_table_arg,
        out->output_string(out, str);
 }
 
+static struct screen_info *setup_graphics(efi_system_table_t *sys_table_arg)
+{
+       efi_guid_t gop_proto = EFI_GRAPHICS_OUTPUT_PROTOCOL_GUID;
+       efi_status_t status;
+       unsigned long size;
+       void **gop_handle = NULL;
+       struct screen_info *si = NULL;
+
+       size = 0;
+       status = efi_call_early(locate_handle, EFI_LOCATE_BY_PROTOCOL,
+                               &gop_proto, NULL, &size, gop_handle);
+       if (status == EFI_BUFFER_TOO_SMALL) {
+               si = alloc_screen_info(sys_table_arg);
+               if (!si)
+                       return NULL;
+               efi_setup_gop(sys_table_arg, si, &gop_proto, size);
+       }
+       return si;
+}
 
 /*
  * This function handles the architcture specific differences between arm and
@@ -208,6 +227,7 @@ unsigned long efi_entry(void *handle, efi_system_table_t *sys_table,
        unsigned long reserve_addr = 0;
        unsigned long reserve_size = 0;
        int secure_boot = 0;
+       struct screen_info *si;
 
        /* Check if we were booted by the EFI firmware */
        if (sys_table->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE)
@@ -260,6 +280,8 @@ unsigned long efi_entry(void *handle, efi_system_table_t *sys_table,
                        __nokaslr = true;
        }
 
+       si = setup_graphics(sys_table);
+
        status = handle_kernel_image(sys_table, image_addr, &image_size,
                                     &reserve_addr,
                                     &reserve_size,
@@ -341,6 +363,7 @@ fail_free_image:
        efi_free(sys_table, image_size, *image_addr);
        efi_free(sys_table, reserve_size, reserve_addr);
 fail_free_cmdline:
+       free_screen_info(sys_table, si);
        efi_free(sys_table, cmdline_size, (unsigned long)cmdline_ptr);
 fail:
        return EFI_ERROR;