[PATCH v3 0/2] Add support for eGPUs on Apple Products

[PATCH v3 0/2] Add support for eGPUs on Apple Products

[Atharva Tiwari]

This series adds support for eGPUs on Apple products, by
enabling apple-set-os on all apple devices.

A side effect of this patch is that the iGPU becomes enabled on iMacs.
However, iMacs can’t use the iGPU to drive the display
(They can't link-train the internal display),
so displays must be disabled on iMacs.

Changes in v3:
- Disabled apple-set-os on MacBookAir6,1 and 7,1 to avoid regressions
- Reworded 1st patch
Changes in v2:
- Reworded cover-letter
- Transferred logic to has_no_display in the 2nd patch

Link to v2:
https://lore.kernel.org/all/20260128145855.1071-1-atharvatiwarilinuxdev@gmail.com/#t

Link to v1:
https://lore.kernel.org/all/20260125001111.1269-1-atharvatiwarilinuxdev@gmail.com/

Atharva Tiwari (2):
  efi/libstub: Enable apple-set-os for most apple devices
  drm/i915/display: Disable display for iMac's

 drivers/firmware/efi/libstub/x86-stub.c       | 20 +++++++------------
 .../drm/i915/display/intel_display_device.c   | 14 ++++++++++++-
 2 files changed, 20 insertions(+), 14 deletions(-)

-- 
2.43.0

[PATCH v3 1/2] efi/libstub: Enable apple-set-os for most apple devices

[Atharva Tiwari]

Enable apple-set-os on Apple Mac systems by default.

Exclude MacBook6,2 and MacBookAir7,2, as enabling apple-set-os on
these models causes regressions.

(tested on iMac20,1)

Signed-off-by: Atharva Tiwari <atharvatiwarilinuxdev@gmail.com>
---
 drivers/firmware/efi/libstub/x86-stub.c | 20 +++++++-------------
 1 file changed, 7 insertions(+), 13 deletions(-)

diff --git a/drivers/firmware/efi/libstub/x86-stub.c b/drivers/firmware/efi/libstub/x86-stub.c
index cef32e2c82d8..532a713adef5 100644
--- a/drivers/firmware/efi/libstub/x86-stub.c
+++ b/drivers/firmware/efi/libstub/x86-stub.c
@@ -303,15 +303,9 @@ static const struct efi_smbios_record *get_table_record(u8 type)
 
 static bool apple_match_product_name(void)
 {
-	static const char type1_product_matches[][15] = {
-		"MacBookPro11,3",
-		"MacBookPro11,5",
-		"MacBookPro13,3",
-		"MacBookPro14,3",
-		"MacBookPro15,1",
-		"MacBookPro15,3",
-		"MacBookPro16,1",
-		"MacBookPro16,4",
+	static const char disabled_product_matches[][14] = {
+		"MacBookPro6,2",
+		"MacBookPro7,2",
 	};
 	const struct efi_smbios_type1_record *record;
 	const u8 *product;
@@ -325,12 +319,12 @@ static bool apple_match_product_name(void)
 	if (!product)
 		return false;
 
-	for (int i = 0; i < ARRAY_SIZE(type1_product_matches); i++) {
-		if (!strcmp(product, type1_product_matches[i]))
-			return true;
+	for (int i = 0; i < ARRAY_SIZE(disabled_product_matches); i++) {
+		if (!strcmp(product, disabled_product_matches[i]))
+			return false;
 	}
 
-	return false;
+	return true;
 }
 
 static void apple_set_os(void)
-- 
2.43.0

[PATCH v3 2/2] drm/i915/display: Disable display for iMac's

[Atharva Tiwari]

Disable display on iMacs, as they can't do link training
on the internal display.

(tested on iMac20,1)

Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Atharva Tiwari <atharvatiwarilinuxdev@gmail.com>
---
 .../gpu/drm/i915/display/intel_display_device.c    | 14 +++++++++++++-
 1 file changed, 13 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/display/intel_display_device.c b/drivers/gpu/drm/i915/display/intel_display_device.c
index 1170afaa8680..b1fec1018d7e 100644
--- a/drivers/gpu/drm/i915/display/intel_display_device.c
+++ b/drivers/gpu/drm/i915/display/intel_display_device.c
@@ -3,6 +3,7 @@
  * Copyright © 2023 Intel Corporation
  */
 
+#include <linux/dmi.h>
 #include <linux/pci.h>
 
 #include <drm/drm_color_mgmt.h>
@@ -1435,7 +1436,18 @@ static bool has_no_display(struct pci_dev *pdev)
 		{}
 	};
 
-	return pci_match_id(ids, pdev);
+	static const struct dmi_system_id dmi_ids[] = {
+		{
+			.ident = "Apple Inc. iMac",
+			.matches = {
+				DMI_EXACT_MATCH(DMI_BOARD_VENDOR, "Apple Inc."),
+				DMI_MATCH(DMI_PRODUCT_NAME, "iMac"),
+			}
+		},
+		{}
+	};
+
+	return pci_match_id(ids, pdev) || dmi_check_system(dmi_ids);
 }
 
 #define INTEL_DISPLAY_DEVICE(_id, _desc) { .devid = (_id), .desc = (_desc) }
-- 
2.43.0

Re: [PATCH v3 2/2] drm/i915/display: Disable display for iMac's

[Jani Nikula]

On Tue, 03 Feb 2026, Atharva Tiwari <atharvatiwarilinuxdev@gmail.com> wrote:
> Disable display on iMacs, as they can't do link training
> on the internal display.
>
> (tested on iMac20,1)

I thought there were open review comments about this. Why are you
resending the same thing?

BR,
Jani.


>
> Reviewed-by: Jani Nikula <jani.nikula@intel.com>
> Signed-off-by: Atharva Tiwari <atharvatiwarilinuxdev@gmail.com>
> ---
>  .../gpu/drm/i915/display/intel_display_device.c    | 14 +++++++++++++-
>  1 file changed, 13 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_display_device.c b/drivers/gpu/drm/i915/display/intel_display_device.c
> index 1170afaa8680..b1fec1018d7e 100644
> --- a/drivers/gpu/drm/i915/display/intel_display_device.c
> +++ b/drivers/gpu/drm/i915/display/intel_display_device.c
> @@ -3,6 +3,7 @@
>   * Copyright © 2023 Intel Corporation
>   */
>  
> +#include <linux/dmi.h>
>  #include <linux/pci.h>
>  
>  #include <drm/drm_color_mgmt.h>
> @@ -1435,7 +1436,18 @@ static bool has_no_display(struct pci_dev *pdev)
>  		{}
>  	};
>  
> -	return pci_match_id(ids, pdev);
> +	static const struct dmi_system_id dmi_ids[] = {
> +		{
> +			.ident = "Apple Inc. iMac",
> +			.matches = {
> +				DMI_EXACT_MATCH(DMI_BOARD_VENDOR, "Apple Inc."),
> +				DMI_MATCH(DMI_PRODUCT_NAME, "iMac"),
> +			}
> +		},
> +		{}
> +	};
> +
> +	return pci_match_id(ids, pdev) || dmi_check_system(dmi_ids);
>  }
>  
>  #define INTEL_DISPLAY_DEVICE(_id, _desc) { .devid = (_id), .desc = (_desc) }

-- 
Jani Nikula, Intel

Re: [PATCH v3 2/2] drm/i915/display: Disable display for iMac's

[Ard Biesheuvel]

On Tue, 3 Feb 2026, at 08:31, Atharva Tiwari wrote:
> Disable display on iMacs, as they can't do link training
> on the internal display.
>
> (tested on iMac20,1)
>

How will you use the iMac if you disable the display?

If this is not in fact what you are doing, please explain in the commit log what exactly you are disabling and why.