* [PATCH 1/3] efi: Wrap screen_info in efi_screen_info so edid_info can be added later
2025-11-19 12:30 [PATCH 0/3] video/efi: Support FIRMWARE_EDID on non-x86 Ard Biesheuvel
@ 2025-11-19 12:30 ` Ard Biesheuvel
2025-11-19 12:30 ` [PATCH 2/3] video/edid: Use getter function for edid_info Ard Biesheuvel
` (2 subsequent siblings)
3 siblings, 0 replies; 8+ messages in thread
From: Ard Biesheuvel @ 2025-11-19 12:30 UTC (permalink / raw)
To: linux-efi
Cc: linux-kernel, Ard Biesheuvel, Thomas Zimmermann,
Javier Martinez Canillas
From: Ard Biesheuvel <ardb@kernel.org>
Prepare for adding support to the EFI stub to pass edid_info discovered
using EFI boot services to the kernel proper via a EFI configuration
table. Instead of passing struct screen_info directly, define a new
struct efi_screen_info that encapsulates it. struct edid_info will be
added there later.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
---
drivers/firmware/efi/earlycon.c | 1 -
drivers/firmware/efi/efi-init.c | 11 ++++++-----
drivers/firmware/efi/libstub/efi-stub-entry.c | 3 +--
drivers/firmware/efi/libstub/efi-stub.c | 9 ++++-----
drivers/firmware/efi/libstub/efistub.h | 6 +++---
drivers/firmware/efi/libstub/gop.c | 1 -
drivers/firmware/efi/libstub/screen_info.c | 7 +++----
drivers/firmware/efi/libstub/zboot.c | 2 +-
drivers/firmware/efi/sysfb_efi.c | 1 -
include/linux/efi.h | 6 +++++-
10 files changed, 23 insertions(+), 24 deletions(-)
diff --git a/drivers/firmware/efi/earlycon.c b/drivers/firmware/efi/earlycon.c
index d18a1a5de144..23fb23867b56 100644
--- a/drivers/firmware/efi/earlycon.c
+++ b/drivers/firmware/efi/earlycon.c
@@ -9,7 +9,6 @@
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/serial_core.h>
-#include <linux/screen_info.h>
#include <linux/string.h>
#include <asm/early_ioremap.h>
diff --git a/drivers/firmware/efi/efi-init.c b/drivers/firmware/efi/efi-init.c
index a65c2d5b9e7b..5896f4e699a1 100644
--- a/drivers/firmware/efi/efi-init.c
+++ b/drivers/firmware/efi/efi-init.c
@@ -19,7 +19,6 @@
#include <linux/of_address.h>
#include <linux/of_fdt.h>
#include <linux/platform_device.h>
-#include <linux/screen_info.h>
#include <asm/efi.h>
@@ -61,13 +60,15 @@ extern __weak const efi_config_table_type_t efi_arch_tables[];
* everything else can get it from here.
*/
#if !defined(CONFIG_X86) && (defined(CONFIG_SYSFB) || defined(CONFIG_EFI_EARLYCON))
-struct screen_info screen_info __section(".data");
+struct efi_screen_info efi_screen_info __section(".data");
+
+extern struct screen_info screen_info __alias(efi_screen_info);
EXPORT_SYMBOL_GPL(screen_info);
#endif
static void __init init_screen_info(void)
{
- struct screen_info *si;
+ struct efi_screen_info *si;
if (screen_info_table != EFI_INVALID_TABLE_ADDR) {
si = early_memremap(screen_info_table, sizeof(*si));
@@ -75,8 +76,8 @@ static void __init init_screen_info(void)
pr_err("Could not map screen_info config table\n");
return;
}
- screen_info = *si;
- memset(si, 0, sizeof(*si));
+ efi_screen_info = *si;
+ si->screen_info = (struct screen_info){};
early_memunmap(si, sizeof(*si));
if (memblock_is_map_memory(screen_info.lfb_base))
diff --git a/drivers/firmware/efi/libstub/efi-stub-entry.c b/drivers/firmware/efi/libstub/efi-stub-entry.c
index a6c049835190..520f5ea31cfd 100644
--- a/drivers/firmware/efi/libstub/efi-stub-entry.c
+++ b/drivers/firmware/efi/libstub/efi-stub-entry.c
@@ -1,7 +1,6 @@
// SPDX-License-Identifier: GPL-2.0-only
#include <linux/efi.h>
-#include <linux/screen_info.h>
#include <asm/efi.h>
@@ -9,7 +8,7 @@
static unsigned long screen_info_offset;
-struct screen_info *alloc_screen_info(void)
+struct efi_screen_info *alloc_screen_info(void)
{
if (IS_ENABLED(CONFIG_ARM))
return __alloc_screen_info();
diff --git a/drivers/firmware/efi/libstub/efi-stub.c b/drivers/firmware/efi/libstub/efi-stub.c
index 9cb814c5ba1b..fe77c285a547 100644
--- a/drivers/firmware/efi/libstub/efi-stub.c
+++ b/drivers/firmware/efi/libstub/efi-stub.c
@@ -10,7 +10,6 @@
*/
#include <linux/efi.h>
-#include <linux/screen_info.h>
#include <asm/efi.h>
#include "efistub.h"
@@ -48,13 +47,13 @@
static u64 virtmap_base = EFI_RT_VIRTUAL_BASE;
static bool flat_va_mapping = (EFI_RT_VIRTUAL_OFFSET != 0);
-void __weak free_screen_info(struct screen_info *si)
+void __weak free_screen_info(struct efi_screen_info *si)
{
}
-static struct screen_info *setup_graphics(void)
+static struct efi_screen_info *setup_graphics(void)
{
- struct screen_info *si, tmp = {};
+ struct efi_screen_info *si, tmp = {};
if (efi_setup_graphics(&tmp, NULL) != EFI_SUCCESS)
return NULL;
@@ -145,7 +144,7 @@ efi_status_t efi_stub_common(efi_handle_t handle,
unsigned long image_addr,
char *cmdline_ptr)
{
- struct screen_info *si;
+ struct efi_screen_info *si;
efi_status_t status;
status = check_platform_features();
diff --git a/drivers/firmware/efi/libstub/efistub.h b/drivers/firmware/efi/libstub/efistub.h
index b2fb0c3fa721..bdeb28d42a1a 100644
--- a/drivers/firmware/efi/libstub/efistub.h
+++ b/drivers/firmware/efi/libstub/efistub.h
@@ -1175,9 +1175,9 @@ efi_enable_reset_attack_mitigation(void) { }
void efi_retrieve_eventlog(void);
-struct screen_info *alloc_screen_info(void);
-struct screen_info *__alloc_screen_info(void);
-void free_screen_info(struct screen_info *si);
+struct efi_screen_info *alloc_screen_info(void);
+struct efi_screen_info *__alloc_screen_info(void);
+void free_screen_info(struct efi_screen_info *si);
void efi_cache_sync_image(unsigned long image_base,
unsigned long alloc_size);
diff --git a/drivers/firmware/efi/libstub/gop.c b/drivers/firmware/efi/libstub/gop.c
index 72d74436a7a4..db80f2ad2871 100644
--- a/drivers/firmware/efi/libstub/gop.c
+++ b/drivers/firmware/efi/libstub/gop.c
@@ -8,7 +8,6 @@
#include <linux/bitops.h>
#include <linux/ctype.h>
#include <linux/efi.h>
-#include <linux/screen_info.h>
#include <linux/string.h>
#include <asm/efi.h>
#include <asm/setup.h>
diff --git a/drivers/firmware/efi/libstub/screen_info.c b/drivers/firmware/efi/libstub/screen_info.c
index 5d3a1e32d177..189da1efb7b2 100644
--- a/drivers/firmware/efi/libstub/screen_info.c
+++ b/drivers/firmware/efi/libstub/screen_info.c
@@ -1,7 +1,6 @@
// SPDX-License-Identifier: GPL-2.0
#include <linux/efi.h>
-#include <linux/screen_info.h>
#include <asm/efi.h>
@@ -21,9 +20,9 @@
static efi_guid_t screen_info_guid = LINUX_EFI_SCREEN_INFO_TABLE_GUID;
-struct screen_info *__alloc_screen_info(void)
+struct efi_screen_info *__alloc_screen_info(void)
{
- struct screen_info *si;
+ struct efi_screen_info *si;
efi_status_t status;
status = efi_bs_call(allocate_pool, EFI_ACPI_RECLAIM_MEMORY,
@@ -43,7 +42,7 @@ struct screen_info *__alloc_screen_info(void)
return NULL;
}
-void free_screen_info(struct screen_info *si)
+void free_screen_info(struct efi_screen_info *si)
{
if (!si)
return;
diff --git a/drivers/firmware/efi/libstub/zboot.c b/drivers/firmware/efi/libstub/zboot.c
index c47ace06f010..86f4814cfd47 100644
--- a/drivers/firmware/efi/libstub/zboot.c
+++ b/drivers/firmware/efi/libstub/zboot.c
@@ -26,7 +26,7 @@ void __weak efi_cache_sync_image(unsigned long image_base,
// executable code loaded into memory to be safe for execution.
}
-struct screen_info *alloc_screen_info(void)
+struct efi_screen_info *alloc_screen_info(void)
{
return __alloc_screen_info();
}
diff --git a/drivers/firmware/efi/sysfb_efi.c b/drivers/firmware/efi/sysfb_efi.c
index 1e509595ac03..092c19771e17 100644
--- a/drivers/firmware/efi/sysfb_efi.c
+++ b/drivers/firmware/efi/sysfb_efi.c
@@ -22,7 +22,6 @@
#include <linux/of_address.h>
#include <linux/pci.h>
#include <linux/platform_device.h>
-#include <linux/screen_info.h>
#include <linux/sysfb.h>
#include <video/vga.h>
diff --git a/include/linux/efi.h b/include/linux/efi.h
index a01f3fe20dab..75d05dc1b4ee 100644
--- a/include/linux/efi.h
+++ b/include/linux/efi.h
@@ -27,7 +27,7 @@
#include <asm/page.h>
-struct screen_info;
+#include <linux/screen_info.h>
#define EFI_SUCCESS 0
#define EFI_LOAD_ERROR ( 1 | (1UL << (BITS_PER_LONG-1)))
@@ -1361,4 +1361,8 @@ extern struct blocking_notifier_head efivar_ops_nh;
void efivars_generic_ops_register(void);
void efivars_generic_ops_unregister(void);
+struct efi_screen_info {
+ struct screen_info screen_info;
+};
+
#endif /* _LINUX_EFI_H */
--
2.52.0.rc1.455.g30608eb744-goog
^ permalink raw reply related [flat|nested] 8+ messages in thread* [PATCH 2/3] video/edid: Use getter function for edid_info
2025-11-19 12:30 [PATCH 0/3] video/efi: Support FIRMWARE_EDID on non-x86 Ard Biesheuvel
2025-11-19 12:30 ` [PATCH 1/3] efi: Wrap screen_info in efi_screen_info so edid_info can be added later Ard Biesheuvel
@ 2025-11-19 12:30 ` Ard Biesheuvel
2025-11-19 12:30 ` [PATCH 3/3] efi: Add FIRMWARE_EDID support Ard Biesheuvel
2025-11-20 7:56 ` [PATCH 0/3] video/efi: Support FIRMWARE_EDID on non-x86 Thomas Zimmermann
3 siblings, 0 replies; 8+ messages in thread
From: Ard Biesheuvel @ 2025-11-19 12:30 UTC (permalink / raw)
To: linux-efi
Cc: linux-kernel, Ard Biesheuvel, Thomas Zimmermann,
Javier Martinez Canillas
From: Ard Biesheuvel <ardb@kernel.org>
Avoid accessing a global writable buffer directly for edid_info, and
instead, define a getter function returning a pointer to it. And
considering that all callers access only the 'dummy' field, just
return a const u8* directly.
This will be used by non-x86 EFI systems that pass edid_info via a EFI
configuration table.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
---
arch/x86/kernel/setup.c | 8 ++++++--
drivers/gpu/drm/sysfb/efidrm.c | 4 ++--
drivers/gpu/drm/sysfb/vesadrm.c | 4 ++--
drivers/video/fbdev/core/fbmon.c | 4 ++--
include/video/edid.h | 2 +-
5 files changed, 13 insertions(+), 9 deletions(-)
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index 1b2edd07a3e1..526c9c4553c1 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -214,8 +214,12 @@ arch_initcall(init_x86_sysctl);
struct screen_info screen_info;
EXPORT_SYMBOL(screen_info);
#if defined(CONFIG_FIRMWARE_EDID)
-struct edid_info edid_info;
-EXPORT_SYMBOL_GPL(edid_info);
+static struct edid_info edid_info __ro_after_init;
+const u8 *get_edid_info(void)
+{
+ return edid_info.dummy;
+}
+EXPORT_SYMBOL_GPL(get_edid_info);
#endif
extern int root_mountflags;
diff --git a/drivers/gpu/drm/sysfb/efidrm.c b/drivers/gpu/drm/sysfb/efidrm.c
index 1883c4a8604c..e30b93ed4264 100644
--- a/drivers/gpu/drm/sysfb/efidrm.c
+++ b/drivers/gpu/drm/sysfb/efidrm.c
@@ -203,8 +203,8 @@ static struct efidrm_device *efidrm_device_create(struct drm_driver *drv,
&format->format, width, height, stride);
#if defined(CONFIG_FIRMWARE_EDID)
- if (drm_edid_header_is_valid(edid_info.dummy) == 8)
- sysfb->edid = edid_info.dummy;
+ if (drm_edid_header_is_valid(get_edid_info()) == 8)
+ sysfb->edid = get_edid_info();
#endif
sysfb->fb_mode = drm_sysfb_mode(width, height, 0, 0);
sysfb->fb_format = format;
diff --git a/drivers/gpu/drm/sysfb/vesadrm.c b/drivers/gpu/drm/sysfb/vesadrm.c
index 16a4b52d45c6..a4ff78fddc0c 100644
--- a/drivers/gpu/drm/sysfb/vesadrm.c
+++ b/drivers/gpu/drm/sysfb/vesadrm.c
@@ -469,8 +469,8 @@ static struct vesadrm_device *vesadrm_device_create(struct drm_driver *drv,
}
#if defined(CONFIG_FIRMWARE_EDID)
- if (drm_edid_header_is_valid(edid_info.dummy) == 8)
- sysfb->edid = edid_info.dummy;
+ if (drm_edid_header_is_valid(get_edid_info()) == 8)
+ sysfb->edid = get_edid_info();
#endif
sysfb->fb_mode = drm_sysfb_mode(width, height, 0, 0);
sysfb->fb_format = format;
diff --git a/drivers/video/fbdev/core/fbmon.c b/drivers/video/fbdev/core/fbmon.c
index 0a65bef01e3c..caa057c76a88 100644
--- a/drivers/video/fbdev/core/fbmon.c
+++ b/drivers/video/fbdev/core/fbmon.c
@@ -1495,7 +1495,7 @@ const unsigned char *fb_firmware_edid(struct device *device)
{
struct pci_dev *dev = NULL;
struct resource *res = NULL;
- unsigned char *edid = NULL;
+ const unsigned char *edid = NULL;
if (device)
dev = to_pci_dev(device);
@@ -1504,7 +1504,7 @@ const unsigned char *fb_firmware_edid(struct device *device)
res = &dev->resource[PCI_ROM_RESOURCE];
if (res && res->flags & IORESOURCE_ROM_SHADOW)
- edid = edid_info.dummy;
+ edid = get_edid_info();
return edid;
}
diff --git a/include/video/edid.h b/include/video/edid.h
index c2b186b1933a..b8f24c4b2829 100644
--- a/include/video/edid.h
+++ b/include/video/edid.h
@@ -5,7 +5,7 @@
#include <uapi/video/edid.h>
#if defined(CONFIG_FIRMWARE_EDID)
-extern struct edid_info edid_info;
+const u8 *get_edid_info(void) __attribute_const__;
#endif
#endif /* __linux_video_edid_h__ */
--
2.52.0.rc1.455.g30608eb744-goog
^ permalink raw reply related [flat|nested] 8+ messages in thread* [PATCH 3/3] efi: Add FIRMWARE_EDID support
2025-11-19 12:30 [PATCH 0/3] video/efi: Support FIRMWARE_EDID on non-x86 Ard Biesheuvel
2025-11-19 12:30 ` [PATCH 1/3] efi: Wrap screen_info in efi_screen_info so edid_info can be added later Ard Biesheuvel
2025-11-19 12:30 ` [PATCH 2/3] video/edid: Use getter function for edid_info Ard Biesheuvel
@ 2025-11-19 12:30 ` Ard Biesheuvel
2025-11-20 7:56 ` [PATCH 0/3] video/efi: Support FIRMWARE_EDID on non-x86 Thomas Zimmermann
3 siblings, 0 replies; 8+ messages in thread
From: Ard Biesheuvel @ 2025-11-19 12:30 UTC (permalink / raw)
To: linux-efi
Cc: linux-kernel, Ard Biesheuvel, Thomas Zimmermann,
Javier Martinez Canillas
From: Ard Biesheuvel <ardb@kernel.org>
Add support to non-x86 EFI systems for passing the EDID information
discovered by the EFI stub to the kernel proper.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
---
drivers/firmware/efi/efi-init.c | 8 ++++++++
drivers/firmware/efi/libstub/efi-stub.c | 7 ++++++-
drivers/firmware/efi/libstub/efistub.h | 3 ---
drivers/video/Kconfig | 2 +-
include/linux/efi.h | 4 ++++
5 files changed, 19 insertions(+), 5 deletions(-)
diff --git a/drivers/firmware/efi/efi-init.c b/drivers/firmware/efi/efi-init.c
index 5896f4e699a1..d70bd0ec154f 100644
--- a/drivers/firmware/efi/efi-init.c
+++ b/drivers/firmware/efi/efi-init.c
@@ -64,6 +64,14 @@ struct efi_screen_info efi_screen_info __section(".data");
extern struct screen_info screen_info __alias(efi_screen_info);
EXPORT_SYMBOL_GPL(screen_info);
+
+#ifdef CONFIG_FIRMWARE_EDID
+const u8 *get_edid_info(void)
+{
+ return efi_screen_info.edid_info.dummy;
+}
+EXPORT_SYMBOL_GPL(get_edid_info);
+#endif
#endif
static void __init init_screen_info(void)
diff --git a/drivers/firmware/efi/libstub/efi-stub.c b/drivers/firmware/efi/libstub/efi-stub.c
index fe77c285a547..20b606d1cbf0 100644
--- a/drivers/firmware/efi/libstub/efi-stub.c
+++ b/drivers/firmware/efi/libstub/efi-stub.c
@@ -54,8 +54,13 @@ void __weak free_screen_info(struct efi_screen_info *si)
static struct efi_screen_info *setup_graphics(void)
{
struct efi_screen_info *si, tmp = {};
+ struct edid_info *edid_info = NULL;
- if (efi_setup_graphics(&tmp, NULL) != EFI_SUCCESS)
+#ifdef CONFIG_FIRMWARE_EDID
+ edid_info = &tmp.edid_info;
+#endif
+
+ if (efi_setup_graphics(&tmp.screen_info, edid_info) != EFI_SUCCESS)
return NULL;
si = alloc_screen_info();
diff --git a/drivers/firmware/efi/libstub/efistub.h b/drivers/firmware/efi/libstub/efistub.h
index bdeb28d42a1a..93940592e88e 100644
--- a/drivers/firmware/efi/libstub/efistub.h
+++ b/drivers/firmware/efi/libstub/efistub.h
@@ -34,9 +34,6 @@
#define EFI_ALLOC_LIMIT ULONG_MAX
#endif
-struct edid_info;
-struct screen_info;
-
extern bool efi_no5lvl;
extern bool efi_nochunk;
extern bool efi_nokaslr;
diff --git a/drivers/video/Kconfig b/drivers/video/Kconfig
index d51777df12d1..6526827fbc55 100644
--- a/drivers/video/Kconfig
+++ b/drivers/video/Kconfig
@@ -63,7 +63,7 @@ endif # HAS_IOMEM
config FIRMWARE_EDID
bool "Enable firmware EDID"
- depends on X86
+ depends on X86 || EFI_GENERIC_STUB
help
This enables access to the EDID transferred from the firmware.
On x86, this is from the VESA BIOS. DRM display drivers will
diff --git a/include/linux/efi.h b/include/linux/efi.h
index 75d05dc1b4ee..8d8228d73585 100644
--- a/include/linux/efi.h
+++ b/include/linux/efi.h
@@ -28,6 +28,7 @@
#include <asm/page.h>
#include <linux/screen_info.h>
+#include <video/edid.h>
#define EFI_SUCCESS 0
#define EFI_LOAD_ERROR ( 1 | (1UL << (BITS_PER_LONG-1)))
@@ -1363,6 +1364,9 @@ void efivars_generic_ops_unregister(void);
struct efi_screen_info {
struct screen_info screen_info;
+#ifdef CONFIG_FIRMWARE_EDID
+ struct edid_info edid_info;
+#endif
};
#endif /* _LINUX_EFI_H */
--
2.52.0.rc1.455.g30608eb744-goog
^ permalink raw reply related [flat|nested] 8+ messages in thread* Re: [PATCH 0/3] video/efi: Support FIRMWARE_EDID on non-x86
2025-11-19 12:30 [PATCH 0/3] video/efi: Support FIRMWARE_EDID on non-x86 Ard Biesheuvel
` (2 preceding siblings ...)
2025-11-19 12:30 ` [PATCH 3/3] efi: Add FIRMWARE_EDID support Ard Biesheuvel
@ 2025-11-20 7:56 ` Thomas Zimmermann
2025-11-20 8:19 ` Thomas Zimmermann
3 siblings, 1 reply; 8+ messages in thread
From: Thomas Zimmermann @ 2025-11-20 7:56 UTC (permalink / raw)
To: Ard Biesheuvel, linux-efi
Cc: linux-kernel, Ard Biesheuvel, Javier Martinez Canillas
Hi,
thanks for addressing the remaining EDID support.
First of all, you need to cc dri-devel@lists.freedesktop.org on any
further revisions.
Am 19.11.25 um 13:30 schrieb Ard Biesheuvel:
> From: Ard Biesheuvel <ardb@kernel.org>
>
> Refactor the screen_info handling so non-x86 platforms booting via the
> EFI stub also have access to the EDID data exposed by the EFI boot
> services.
I don't like how this series complicates everything to make non-x86
easier. But the general idea of using efi_screen_info goes into the
right direction. It's just not generic enough.
The sysfb code transfers struct screen_info as device parameter [1].
Drivers later fetch it on probe [2]. The direct ref to the global
edid_info [3] only exists because we have no means of transferring it as
device data.
So instead of using efi_screen_info, let's declare struct sysfb_display
with screen_info and edid_info. The header would be linux/sysfb.h. We
transfer this to all related drivers. The generic EFI code would set it
up like efi_screen_info and the x86 code would decalre it at [4];
replacing the existing state.
Best regards
Thomas
[1]
https://elixir.bootlin.com/linux/v6.17.8/source/drivers/firmware/sysfb.c#L205
[2]
https://elixir.bootlin.com/linux/v6.17.8/source/drivers/gpu/drm/sysfb/efidrm.c#L162
[3]
https://elixir.bootlin.com/linux/v6.17.8/source/drivers/gpu/drm/sysfb/efidrm.c#L206
[4]
https://elixir.bootlin.com/linux/v6.17.8/source/arch/x86/kernel/setup.c#L214
>
> Cc: Thomas Zimmermann <tzimmermann@suse.de>
> Cc: Javier Martinez Canillas <javierm@redhat.com>
>
> Ard Biesheuvel (3):
> efi: Wrap screen_info in efi_screen_info so edid_info can be added
> later
> video/edid: Use getter function for edid_info
> efi: Add FIRMWARE_EDID support
>
> arch/x86/kernel/setup.c | 8 ++++++--
> drivers/firmware/efi/earlycon.c | 1 -
> drivers/firmware/efi/efi-init.c | 19 ++++++++++++++-----
> drivers/firmware/efi/libstub/efi-stub-entry.c | 3 +--
> drivers/firmware/efi/libstub/efi-stub.c | 16 ++++++++++------
> drivers/firmware/efi/libstub/efistub.h | 9 +++------
> drivers/firmware/efi/libstub/gop.c | 1 -
> drivers/firmware/efi/libstub/screen_info.c | 7 +++----
> drivers/firmware/efi/libstub/zboot.c | 2 +-
> drivers/firmware/efi/sysfb_efi.c | 1 -
> drivers/gpu/drm/sysfb/efidrm.c | 4 ++--
> drivers/gpu/drm/sysfb/vesadrm.c | 4 ++--
> drivers/video/Kconfig | 2 +-
> drivers/video/fbdev/core/fbmon.c | 4 ++--
> include/linux/efi.h | 10 +++++++++-
> include/video/edid.h | 2 +-
> 16 files changed, 55 insertions(+), 38 deletions(-)
>
--
--
Thomas Zimmermann
Graphics Driver Developer
SUSE Software Solutions Germany GmbH
Frankenstr. 146, 90461 Nürnberg, Germany, www.suse.com
GF: Jochen Jaser, Andrew McDonald, Werner Knoblich, (HRB 36809, AG Nürnberg)
^ permalink raw reply [flat|nested] 8+ messages in thread* Re: [PATCH 0/3] video/efi: Support FIRMWARE_EDID on non-x86
2025-11-20 7:56 ` [PATCH 0/3] video/efi: Support FIRMWARE_EDID on non-x86 Thomas Zimmermann
@ 2025-11-20 8:19 ` Thomas Zimmermann
2025-11-20 8:25 ` Ard Biesheuvel
0 siblings, 1 reply; 8+ messages in thread
From: Thomas Zimmermann @ 2025-11-20 8:19 UTC (permalink / raw)
To: Ard Biesheuvel, linux-efi
Cc: linux-kernel, Ard Biesheuvel, Javier Martinez Canillas
Am 20.11.25 um 08:56 schrieb Thomas Zimmermann:
> Hi,
>
> thanks for addressing the remaining EDID support.
>
> First of all, you need to cc dri-devel@lists.freedesktop.org on any
> further revisions.
>
> Am 19.11.25 um 13:30 schrieb Ard Biesheuvel:
>> From: Ard Biesheuvel <ardb@kernel.org>
>>
>> Refactor the screen_info handling so non-x86 platforms booting via the
>> EFI stub also have access to the EDID data exposed by the EFI boot
>> services.
>
> I don't like how this series complicates everything to make non-x86
> easier. But the general idea of using efi_screen_info goes into the
> right direction. It's just not generic enough.
>
> The sysfb code transfers struct screen_info as device parameter [1].
> Drivers later fetch it on probe [2]. The direct ref to the global
> edid_info [3] only exists because we have no means of transferring it
> as device data.
>
> So instead of using efi_screen_info, let's declare struct
> sysfb_display with screen_info and edid_info. The header would be
> linux/sysfb.h. We transfer this to all related drivers. The generic
> EFI code would set it up like efi_screen_info and the x86 code would
> decalre it at [4]; replacing the existing state.
If this proposal works for EFI, I could do the changes in graphics
drivers and then resubmit the EDID series with an additional patch for
generic EFI.
>
> Best regards
> Thomas
>
> [1]
> https://elixir.bootlin.com/linux/v6.17.8/source/drivers/firmware/sysfb.c#L205
> [2]
> https://elixir.bootlin.com/linux/v6.17.8/source/drivers/gpu/drm/sysfb/efidrm.c#L162
> [3]
> https://elixir.bootlin.com/linux/v6.17.8/source/drivers/gpu/drm/sysfb/efidrm.c#L206
> [4]
> https://elixir.bootlin.com/linux/v6.17.8/source/arch/x86/kernel/setup.c#L214
>
>
>>
>> Cc: Thomas Zimmermann <tzimmermann@suse.de>
>> Cc: Javier Martinez Canillas <javierm@redhat.com>
>>
>> Ard Biesheuvel (3):
>> efi: Wrap screen_info in efi_screen_info so edid_info can be added
>> later
>> video/edid: Use getter function for edid_info
>> efi: Add FIRMWARE_EDID support
>>
>> arch/x86/kernel/setup.c | 8 ++++++--
>> drivers/firmware/efi/earlycon.c | 1 -
>> drivers/firmware/efi/efi-init.c | 19 ++++++++++++++-----
>> drivers/firmware/efi/libstub/efi-stub-entry.c | 3 +--
>> drivers/firmware/efi/libstub/efi-stub.c | 16 ++++++++++------
>> drivers/firmware/efi/libstub/efistub.h | 9 +++------
>> drivers/firmware/efi/libstub/gop.c | 1 -
>> drivers/firmware/efi/libstub/screen_info.c | 7 +++----
>> drivers/firmware/efi/libstub/zboot.c | 2 +-
>> drivers/firmware/efi/sysfb_efi.c | 1 -
>> drivers/gpu/drm/sysfb/efidrm.c | 4 ++--
>> drivers/gpu/drm/sysfb/vesadrm.c | 4 ++--
>> drivers/video/Kconfig | 2 +-
>> drivers/video/fbdev/core/fbmon.c | 4 ++--
>> include/linux/efi.h | 10 +++++++++-
>> include/video/edid.h | 2 +-
>> 16 files changed, 55 insertions(+), 38 deletions(-)
>>
>
--
--
Thomas Zimmermann
Graphics Driver Developer
SUSE Software Solutions Germany GmbH
Frankenstr. 146, 90461 Nürnberg, Germany, www.suse.com
GF: Jochen Jaser, Andrew McDonald, Werner Knoblich, (HRB 36809, AG Nürnberg)
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH 0/3] video/efi: Support FIRMWARE_EDID on non-x86
2025-11-20 8:19 ` Thomas Zimmermann
@ 2025-11-20 8:25 ` Ard Biesheuvel
2025-11-21 14:03 ` Thomas Zimmermann
0 siblings, 1 reply; 8+ messages in thread
From: Ard Biesheuvel @ 2025-11-20 8:25 UTC (permalink / raw)
To: Thomas Zimmermann
Cc: Ard Biesheuvel, linux-efi, linux-kernel, Javier Martinez Canillas
On Thu, 20 Nov 2025 at 09:19, Thomas Zimmermann <tzimmermann@suse.de> wrote:
>
>
>
> Am 20.11.25 um 08:56 schrieb Thomas Zimmermann:
> > Hi,
> >
> > thanks for addressing the remaining EDID support.
> >
> > First of all, you need to cc dri-devel@lists.freedesktop.org on any
> > further revisions.
> >
> > Am 19.11.25 um 13:30 schrieb Ard Biesheuvel:
> >> From: Ard Biesheuvel <ardb@kernel.org>
> >>
> >> Refactor the screen_info handling so non-x86 platforms booting via the
> >> EFI stub also have access to the EDID data exposed by the EFI boot
> >> services.
> >
> > I don't like how this series complicates everything to make non-x86
> > easier. But the general idea of using efi_screen_info goes into the
> > right direction. It's just not generic enough.
> >
> > The sysfb code transfers struct screen_info as device parameter [1].
> > Drivers later fetch it on probe [2]. The direct ref to the global
> > edid_info [3] only exists because we have no means of transferring it
> > as device data.
> >
> > So instead of using efi_screen_info, let's declare struct
> > sysfb_display with screen_info and edid_info. The header would be
> > linux/sysfb.h. We transfer this to all related drivers. The generic
> > EFI code would set it up like efi_screen_info and the x86 code would
> > decalre it at [4]; replacing the existing state.
>
> If this proposal works for EFI, I could do the changes in graphics
> drivers and then resubmit the EDID series with an additional patch for
> generic EFI.
>
That sounds great, thanks.
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH 0/3] video/efi: Support FIRMWARE_EDID on non-x86
2025-11-20 8:25 ` Ard Biesheuvel
@ 2025-11-21 14:03 ` Thomas Zimmermann
0 siblings, 0 replies; 8+ messages in thread
From: Thomas Zimmermann @ 2025-11-21 14:03 UTC (permalink / raw)
To: Ard Biesheuvel
Cc: Ard Biesheuvel, linux-efi, linux-kernel, Javier Martinez Canillas
Hi
Am 20.11.25 um 09:25 schrieb Ard Biesheuvel:
> On Thu, 20 Nov 2025 at 09:19, Thomas Zimmermann <tzimmermann@suse.de> wrote:
>>
>>
>> Am 20.11.25 um 08:56 schrieb Thomas Zimmermann:
>>> Hi,
>>>
>>> thanks for addressing the remaining EDID support.
>>>
>>> First of all, you need to cc dri-devel@lists.freedesktop.org on any
>>> further revisions.
>>>
>>> Am 19.11.25 um 13:30 schrieb Ard Biesheuvel:
>>>> From: Ard Biesheuvel <ardb@kernel.org>
>>>>
>>>> Refactor the screen_info handling so non-x86 platforms booting via the
>>>> EFI stub also have access to the EDID data exposed by the EFI boot
>>>> services.
>>> I don't like how this series complicates everything to make non-x86
>>> easier. But the general idea of using efi_screen_info goes into the
>>> right direction. It's just not generic enough.
>>>
>>> The sysfb code transfers struct screen_info as device parameter [1].
>>> Drivers later fetch it on probe [2]. The direct ref to the global
>>> edid_info [3] only exists because we have no means of transferring it
>>> as device data.
>>>
>>> So instead of using efi_screen_info, let's declare struct
>>> sysfb_display with screen_info and edid_info. The header would be
>>> linux/sysfb.h. We transfer this to all related drivers. The generic
>>> EFI code would set it up like efi_screen_info and the x86 code would
>>> decalre it at [4]; replacing the existing state.
>> If this proposal works for EFI, I could do the changes in graphics
>> drivers and then resubmit the EDID series with an additional patch for
>> generic EFI.
>>
> That sounds great, thanks.
Series is out at
https://lore.kernel.org/dri-devel/20251121135624.494768-1-tzimmermann@suse.de/
Once/if merged, we can implement EDID support on top of it for all of EFI.
Best regards
Thomas
--
--
Thomas Zimmermann
Graphics Driver Developer
SUSE Software Solutions Germany GmbH
Frankenstr. 146, 90461 Nürnberg, Germany, www.suse.com
GF: Jochen Jaser, Andrew McDonald, Werner Knoblich, (HRB 36809, AG Nürnberg)
^ permalink raw reply [flat|nested] 8+ messages in thread