[PATCH v3 0/6] Cleanups for the nomodeset kernel command line parameter logic

[PATCH v3 0/6] Cleanups for the nomodeset kernel command line parameter logic

[Javier Martinez Canillas]

There is a lot of historical baggage on this parameter. It is defined in
the vgacon driver as nomodeset, but its set function is called text_mode()
and the value queried with a function named vgacon_text_force().

All this implies that it's about forcing text mode for VGA, yet it is not
used in neither vgacon nor other console driver. The only users for these
are DRM drivers, that check for the vgacon_text_force() return value to
determine whether the driver should be loaded or not.

That makes it quite confusing to read the code, because the variables and
function names don't reflect what they actually do and also are not in the
same subsystem as the drivers that make use of them.

This patch-set attempts to cleanup the code by moving the nomodseset param
to the DRM subsystem and do some renaming to make their intention clearer.

This is a v3 of the patches, that address issues pointed out by Jani Nikula
in v2: https://lkml.org/lkml/2021/11/4/594

Patch #1 and #2 are just trivial cleanups.

Patch #3 moves the nomodeset boot option to the DRM subsystem and renames
the variables and functions names.

Patch #4 removes the relationship between the nomodeset parameter and the
CONFIG_VGA_CONSOLE Kconfig symbol.

Patch #5 adds nomodeset to the kernel parameters documentation.

Patch #6 improves the message when nomodeset is enabled to make it more
accurate and less sensational.

Changes in v3:
- Drop the drm_drv_enabled() function and just call to drm_get_modeset().
- Make drm_get_modeset() just a getter function and don't return an error.
- Move independent cleanups in drivers as separate preparatory patches.

Changes in v2:
- Conditionally build drm_nomodeset.o if CONFIG_VGA_CONSOLE is set.
- Squash patches to move nomodeset logic to DRM and do the renaming.
- Name the function drm_check_modeset() and make it return -ENODEV.
- Squash patch to add drm_drv_enabled() and make drivers use it.
- Make the drivers changes before moving nomodeset logic to DRM.
- Make drm_drv_enabled() return an errno and -ENODEV if nomodeset.
- Remove debug and error messages in drivers.

Javier Martinez Canillas (6):
  drm: Don't print messages if drivers are disabled due nomodeset
  drm/vboxvideo: Drop CONFIG_VGA_CONSOLE guard to call
    vgacon_text_force()
  drm: Move nomodeset kernel parameter to the DRM subsystem
  drm: Decouple nomodeset from CONFIG_VGA_CONSOLE
  Documentation/admin-guide: Document nomodeset kernel parameter
  drm: Make the nomodeset message less sensational

 .../admin-guide/kernel-parameters.txt         |  4 ++++
 drivers/gpu/drm/Kconfig                       |  6 +++++
 drivers/gpu/drm/Makefile                      |  2 ++
 drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c       |  6 ++---
 drivers/gpu/drm/ast/ast_drv.c                 |  4 ++--
 drivers/gpu/drm/drm_nomodeset.c               | 24 +++++++++++++++++++
 drivers/gpu/drm/i915/i915_module.c            |  4 ++--
 drivers/gpu/drm/mgag200/mgag200_drv.c         |  4 ++--
 drivers/gpu/drm/nouveau/nouveau_drm.c         |  4 ++--
 drivers/gpu/drm/qxl/qxl_drv.c                 |  4 ++--
 drivers/gpu/drm/radeon/radeon_drv.c           | 10 +++-----
 drivers/gpu/drm/tiny/bochs.c                  |  4 ++--
 drivers/gpu/drm/tiny/cirrus.c                 |  5 ++--
 drivers/gpu/drm/vboxvideo/vbox_drv.c          |  6 ++---
 drivers/gpu/drm/virtio/virtgpu_drv.c          |  4 ++--
 drivers/gpu/drm/vmwgfx/vmwgfx_drv.c           |  4 ++--
 drivers/video/console/vgacon.c                | 21 ----------------
 include/drm/drm_mode_config.h                 |  2 ++
 include/linux/console.h                       |  6 -----
 19 files changed, 64 insertions(+), 60 deletions(-)
 create mode 100644 drivers/gpu/drm/drm_nomodeset.c

-- 
2.33.1

[PATCH v3 0/6] Cleanups for the nomodeset kernel command line parameter logic

[Javier Martinez Canillas]

There is a lot of historical baggage on this parameter. It is defined in
the vgacon driver as nomodeset, but its set function is called text_mode()
and the value queried with a function named vgacon_text_force().

All this implies that it's about forcing text mode for VGA, yet it is not
used in neither vgacon nor other console driver. The only users for these
are DRM drivers, that check for the vgacon_text_force() return value to
determine whether the driver should be loaded or not.

That makes it quite confusing to read the code, because the variables and
function names don't reflect what they actually do and also are not in the
same subsystem as the drivers that make use of them.

This patch-set attempts to cleanup the code by moving the nomodseset param
to the DRM subsystem and do some renaming to make their intention clearer.

This is a v3 of the patches, that address issues pointed out by Jani Nikula
in v2: https://lkml.org/lkml/2021/11/4/594

Patch #1 and #2 are just trivial cleanups.

Patch #3 moves the nomodeset boot option to the DRM subsystem and renames
the variables and functions names.

Patch #4 removes the relationship between the nomodeset parameter and the
CONFIG_VGA_CONSOLE Kconfig symbol.

Patch #5 adds nomodeset to the kernel parameters documentation.

Patch #6 improves the message when nomodeset is enabled to make it more
accurate and less sensational.

Changes in v3:
- Drop the drm_drv_enabled() function and just call to drm_get_modeset().
- Make drm_get_modeset() just a getter function and don't return an error.
- Move independent cleanups in drivers as separate preparatory patches.

Changes in v2:
- Conditionally build drm_nomodeset.o if CONFIG_VGA_CONSOLE is set.
- Squash patches to move nomodeset logic to DRM and do the renaming.
- Name the function drm_check_modeset() and make it return -ENODEV.
- Squash patch to add drm_drv_enabled() and make drivers use it.
- Make the drivers changes before moving nomodeset logic to DRM.
- Make drm_drv_enabled() return an errno and -ENODEV if nomodeset.
- Remove debug and error messages in drivers.

Javier Martinez Canillas (6):
  drm: Don't print messages if drivers are disabled due nomodeset
  drm/vboxvideo: Drop CONFIG_VGA_CONSOLE guard to call
    vgacon_text_force()
  drm: Move nomodeset kernel parameter to the DRM subsystem
  drm: Decouple nomodeset from CONFIG_VGA_CONSOLE
  Documentation/admin-guide: Document nomodeset kernel parameter
  drm: Make the nomodeset message less sensational

 .../admin-guide/kernel-parameters.txt         |  4 ++++
 drivers/gpu/drm/Kconfig                       |  6 +++++
 drivers/gpu/drm/Makefile                      |  2 ++
 drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c       |  6 ++---
 drivers/gpu/drm/ast/ast_drv.c                 |  4 ++--
 drivers/gpu/drm/drm_nomodeset.c               | 24 +++++++++++++++++++
 drivers/gpu/drm/i915/i915_module.c            |  4 ++--
 drivers/gpu/drm/mgag200/mgag200_drv.c         |  4 ++--
 drivers/gpu/drm/nouveau/nouveau_drm.c         |  4 ++--
 drivers/gpu/drm/qxl/qxl_drv.c                 |  4 ++--
 drivers/gpu/drm/radeon/radeon_drv.c           | 10 +++-----
 drivers/gpu/drm/tiny/bochs.c                  |  4 ++--
 drivers/gpu/drm/tiny/cirrus.c                 |  5 ++--
 drivers/gpu/drm/vboxvideo/vbox_drv.c          |  6 ++---
 drivers/gpu/drm/virtio/virtgpu_drv.c          |  4 ++--
 drivers/gpu/drm/vmwgfx/vmwgfx_drv.c           |  4 ++--
 drivers/video/console/vgacon.c                | 21 ----------------
 include/drm/drm_mode_config.h                 |  2 ++
 include/linux/console.h                       |  6 -----
 19 files changed, 64 insertions(+), 60 deletions(-)
 create mode 100644 drivers/gpu/drm/drm_nomodeset.c

-- 
2.33.1

[PATCH v3 1/6] drm: Don't print messages if drivers are disabled due nomodeset

[Javier Martinez Canillas]

The nomodeset kernel parameter handler already prints a message that the
DRM drivers will be disabled, so there's no need for drivers to do that.

Suggested-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
---

(no changes since v1)

 drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c | 4 +---
 drivers/gpu/drm/radeon/radeon_drv.c     | 8 ++------
 2 files changed, 3 insertions(+), 9 deletions(-)

diff --git drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
index c718fb5f3f8a..289d04999ced 100644
--- drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
+++ drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
@@ -2514,10 +2514,8 @@ static int __init amdgpu_init(void)
 {
 	int r;
 
-	if (vgacon_text_force()) {
-		DRM_ERROR("VGACON disables amdgpu kernel modesetting.\n");
+	if (vgacon_text_force())
 		return -EINVAL;
-	}
 
 	r = amdgpu_sync_init();
 	if (r)
diff --git drivers/gpu/drm/radeon/radeon_drv.c drivers/gpu/drm/radeon/radeon_drv.c
index b74cebca1f89..380adc61e71c 100644
--- drivers/gpu/drm/radeon/radeon_drv.c
+++ drivers/gpu/drm/radeon/radeon_drv.c
@@ -637,15 +637,11 @@ static struct pci_driver radeon_kms_pci_driver = {
 
 static int __init radeon_module_init(void)
 {
-	if (vgacon_text_force() && radeon_modeset == -1) {
-		DRM_INFO("VGACON disable radeon kernel modesetting.\n");
+	if (vgacon_text_force() && radeon_modeset == -1)
 		radeon_modeset = 0;
-	}
 
-	if (radeon_modeset == 0) {
-		DRM_ERROR("No UMS support in radeon module!\n");
+	if (radeon_modeset == 0)
 		return -EINVAL;
-	}
 
 	DRM_INFO("radeon kernel modesetting enabled.\n");
 	radeon_register_atpx_handler();
-- 
2.33.1

[PATCH v3 1/6] drm: Don't print messages if drivers are disabled due nomodeset

[Javier Martinez Canillas]

The nomodeset kernel parameter handler already prints a message that the
DRM drivers will be disabled, so there's no need for drivers to do that.

Suggested-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
---

(no changes since v1)

 drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c | 4 +---
 drivers/gpu/drm/radeon/radeon_drv.c     | 8 ++------
 2 files changed, 3 insertions(+), 9 deletions(-)

diff --git drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
index c718fb5f3f8a..289d04999ced 100644
--- drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
+++ drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
@@ -2514,10 +2514,8 @@ static int __init amdgpu_init(void)
 {
 	int r;
 
-	if (vgacon_text_force()) {
-		DRM_ERROR("VGACON disables amdgpu kernel modesetting.\n");
+	if (vgacon_text_force())
 		return -EINVAL;
-	}
 
 	r = amdgpu_sync_init();
 	if (r)
diff --git drivers/gpu/drm/radeon/radeon_drv.c drivers/gpu/drm/radeon/radeon_drv.c
index b74cebca1f89..380adc61e71c 100644
--- drivers/gpu/drm/radeon/radeon_drv.c
+++ drivers/gpu/drm/radeon/radeon_drv.c
@@ -637,15 +637,11 @@ static struct pci_driver radeon_kms_pci_driver = {
 
 static int __init radeon_module_init(void)
 {
-	if (vgacon_text_force() && radeon_modeset == -1) {
-		DRM_INFO("VGACON disable radeon kernel modesetting.\n");
+	if (vgacon_text_force() && radeon_modeset == -1)
 		radeon_modeset = 0;
-	}
 
-	if (radeon_modeset == 0) {
-		DRM_ERROR("No UMS support in radeon module!\n");
+	if (radeon_modeset == 0)
 		return -EINVAL;
-	}
 
 	DRM_INFO("radeon kernel modesetting enabled.\n");
 	radeon_register_atpx_handler();
-- 
2.33.1

[PATCH v3 2/6] drm/vboxvideo: Drop CONFIG_VGA_CONSOLE guard to call vgacon_text_force()

[Javier Martinez Canillas]

It is already handled by the console.h macro since a stub inline function
is defined for vgacon_text_force() if CONFIG_VGA_CONSOLE is not set.

There's no need to have ifdefery in the driver when calling the function.

Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
---

(no changes since v1)

 drivers/gpu/drm/vboxvideo/vbox_drv.c | 2 --
 1 file changed, 2 deletions(-)

diff --git drivers/gpu/drm/vboxvideo/vbox_drv.c drivers/gpu/drm/vboxvideo/vbox_drv.c
index a6c81af37345..fd7abb029c65 100644
--- drivers/gpu/drm/vboxvideo/vbox_drv.c
+++ drivers/gpu/drm/vboxvideo/vbox_drv.c
@@ -193,10 +193,8 @@ static const struct drm_driver driver = {
 
 static int __init vbox_init(void)
 {
-#ifdef CONFIG_VGA_CONSOLE
 	if (vgacon_text_force() && vbox_modeset == -1)
 		return -EINVAL;
-#endif
 
 	if (vbox_modeset == 0)
 		return -EINVAL;
-- 
2.33.1

[PATCH v3 2/6] drm/vboxvideo: Drop CONFIG_VGA_CONSOLE guard to call vgacon_text_force()

[Javier Martinez Canillas]

It is already handled by the console.h macro since a stub inline function
is defined for vgacon_text_force() if CONFIG_VGA_CONSOLE is not set.

There's no need to have ifdefery in the driver when calling the function.

Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
---

(no changes since v1)

 drivers/gpu/drm/vboxvideo/vbox_drv.c | 2 --
 1 file changed, 2 deletions(-)

diff --git drivers/gpu/drm/vboxvideo/vbox_drv.c drivers/gpu/drm/vboxvideo/vbox_drv.c
index a6c81af37345..fd7abb029c65 100644
--- drivers/gpu/drm/vboxvideo/vbox_drv.c
+++ drivers/gpu/drm/vboxvideo/vbox_drv.c
@@ -193,10 +193,8 @@ static const struct drm_driver driver = {
 
 static int __init vbox_init(void)
 {
-#ifdef CONFIG_VGA_CONSOLE
 	if (vgacon_text_force() && vbox_modeset == -1)
 		return -EINVAL;
-#endif
 
 	if (vbox_modeset == 0)
 		return -EINVAL;
-- 
2.33.1

[PATCH v3 3/6] drm: Move nomodeset kernel parameter to the DRM subsystem

[Javier Martinez Canillas]

The "nomodeset" kernel cmdline parameter is handled by the vgacon driver
but the exported vgacon_text_force() symbol is only used by DRM drivers.

It makes much more sense for the parameter logic to be in the subsystem
of the drivers that are making use of it.

Let's move the vgacon_text_force() function and related logic to the DRM
subsystem. While doing that, rename the function to drm_get_modeset() and
make it return true if modesetting is enabled and false otherwise. This
better reflects the condition that drivers are actually testing for.

Suggested-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
---

Changes in v3:
- Drop the drm_drv_enabled() function and just call to drm_get_modeset().
- Make drm_get_modeset() just a getter function and don't return an error.
- Move independent cleanups in drivers as separate preparatory patches.

Changes in v2:
- Conditionally build drm_nomodeset.o if CONFIG_VGA_CONSOLE is set.
- Squash patches to move nomodeset logic to DRM and do the renaming.
- Name the function drm_check_modeset() and make it return -ENODEV.
- Squash patch to add drm_drv_enabled() and make drivers use it.
- Make the drivers changes before moving nomodeset logic to DRM.
- Make drm_drv_enabled() return an errno and -ENODEV if nomodeset.
- Remove debug and error messages in drivers.

 drivers/gpu/drm/Makefile                |  2 ++
 drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c |  4 ++--
 drivers/gpu/drm/ast/ast_drv.c           |  4 ++--
 drivers/gpu/drm/drm_nomodeset.c         | 26 +++++++++++++++++++++++++
 drivers/gpu/drm/i915/i915_module.c      |  4 ++--
 drivers/gpu/drm/mgag200/mgag200_drv.c   |  4 ++--
 drivers/gpu/drm/nouveau/nouveau_drm.c   |  4 ++--
 drivers/gpu/drm/qxl/qxl_drv.c           |  4 ++--
 drivers/gpu/drm/radeon/radeon_drv.c     |  4 ++--
 drivers/gpu/drm/tiny/bochs.c            |  4 ++--
 drivers/gpu/drm/tiny/cirrus.c           |  5 +++--
 drivers/gpu/drm/vboxvideo/vbox_drv.c    |  4 ++--
 drivers/gpu/drm/virtio/virtgpu_drv.c    |  4 ++--
 drivers/gpu/drm/vmwgfx/vmwgfx_drv.c     |  4 ++--
 drivers/video/console/vgacon.c          | 21 --------------------
 include/drm/drm_mode_config.h           |  6 ++++++
 include/linux/console.h                 |  6 ------
 17 files changed, 59 insertions(+), 51 deletions(-)
 create mode 100644 drivers/gpu/drm/drm_nomodeset.c

diff --git drivers/gpu/drm/Makefile drivers/gpu/drm/Makefile
index 1c41156deb5f..c74810c285af 100644
--- drivers/gpu/drm/Makefile
+++ drivers/gpu/drm/Makefile
@@ -33,6 +33,8 @@ drm-$(CONFIG_DRM_PRIVACY_SCREEN) += drm_privacy_screen.o drm_privacy_screen_x86.
 
 obj-$(CONFIG_DRM_DP_AUX_BUS) += drm_dp_aux_bus.o
 
+obj-$(CONFIG_VGA_CONSOLE) += drm_nomodeset.o
+
 drm_cma_helper-y := drm_gem_cma_helper.o
 obj-$(CONFIG_DRM_GEM_CMA_HELPER) += drm_cma_helper.o
 
diff --git drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
index 289d04999ced..0da7f0b14700 100644
--- drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
+++ drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
@@ -28,10 +28,10 @@
 #include <drm/drm_gem.h>
 #include <drm/drm_vblank.h>
 #include <drm/drm_managed.h>
+#include <drm/drm_mode_config.h>
 #include "amdgpu_drv.h"
 
 #include <drm/drm_pciids.h>
-#include <linux/console.h>
 #include <linux/module.h>
 #include <linux/pm_runtime.h>
 #include <linux/vga_switcheroo.h>
@@ -2514,7 +2514,7 @@ static int __init amdgpu_init(void)
 {
 	int r;
 
-	if (vgacon_text_force())
+	if (!drm_get_modeset())
 		return -EINVAL;
 
 	r = amdgpu_sync_init();
diff --git drivers/gpu/drm/ast/ast_drv.c drivers/gpu/drm/ast/ast_drv.c
index 86d5cd7b6318..e788deac15cb 100644
--- drivers/gpu/drm/ast/ast_drv.c
+++ drivers/gpu/drm/ast/ast_drv.c
@@ -26,7 +26,6 @@
  * Authors: Dave Airlie <airlied@redhat.com>
  */
 
-#include <linux/console.h>
 #include <linux/module.h>
 #include <linux/pci.h>
 
@@ -35,6 +34,7 @@
 #include <drm/drm_crtc_helper.h>
 #include <drm/drm_drv.h>
 #include <drm/drm_gem_vram_helper.h>
+#include <drm/drm_mode_config.h>
 #include <drm/drm_probe_helper.h>
 
 #include "ast_drv.h"
@@ -233,7 +233,7 @@ static struct pci_driver ast_pci_driver = {
 
 static int __init ast_init(void)
 {
-	if (vgacon_text_force() && ast_modeset == -1)
+	if (!drm_get_modeset() && ast_modeset == -1)
 		return -EINVAL;
 
 	if (ast_modeset == 0)
diff --git drivers/gpu/drm/drm_nomodeset.c drivers/gpu/drm/drm_nomodeset.c
new file mode 100644
index 000000000000..fc3acf3ab2e2
--- /dev/null
+++ drivers/gpu/drm/drm_nomodeset.c
@@ -0,0 +1,26 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/module.h>
+#include <linux/types.h>
+
+static bool drm_nomodeset;
+
+bool drm_get_modeset(void)
+{
+	return !drm_nomodeset;
+}
+EXPORT_SYMBOL(drm_get_modeset);
+
+static int __init disable_modeset(char *str)
+{
+	drm_nomodeset = true;
+
+	pr_warn("You have booted with nomodeset. This means your GPU drivers are DISABLED\n");
+	pr_warn("Any video related functionality will be severely degraded, and you may not even be able to suspend the system properly\n");
+	pr_warn("Unless you actually understand what nomodeset does, you should reboot without enabling it\n");
+
+	return 1;
+}
+
+/* Disable kernel modesetting */
+__setup("nomodeset", disable_modeset);
diff --git drivers/gpu/drm/i915/i915_module.c drivers/gpu/drm/i915/i915_module.c
index ab2295dd4500..f952e8b69465 100644
--- drivers/gpu/drm/i915/i915_module.c
+++ drivers/gpu/drm/i915/i915_module.c
@@ -4,7 +4,7 @@
  * Copyright © 2021 Intel Corporation
  */
 
-#include <linux/console.h>
+#include <drm/drm_mode_config.h>
 
 #include "gem/i915_gem_context.h"
 #include "gem/i915_gem_object.h"
@@ -31,7 +31,7 @@ static int i915_check_nomodeset(void)
 	if (i915_modparams.modeset == 0)
 		use_kms = false;
 
-	if (vgacon_text_force() && i915_modparams.modeset == -1)
+	if (!drm_get_modeset() && i915_modparams.modeset == -1)
 		use_kms = false;
 
 	if (!use_kms) {
diff --git drivers/gpu/drm/mgag200/mgag200_drv.c drivers/gpu/drm/mgag200/mgag200_drv.c
index 6b9243713b3c..3df5a608d0e7 100644
--- drivers/gpu/drm/mgag200/mgag200_drv.c
+++ drivers/gpu/drm/mgag200/mgag200_drv.c
@@ -6,7 +6,6 @@
  *          Dave Airlie
  */
 
-#include <linux/console.h>
 #include <linux/module.h>
 #include <linux/pci.h>
 #include <linux/vmalloc.h>
@@ -15,6 +14,7 @@
 #include <drm/drm_drv.h>
 #include <drm/drm_file.h>
 #include <drm/drm_ioctl.h>
+#include <drm/drm_mode_config.h>
 #include <drm/drm_pciids.h>
 
 #include "mgag200_drv.h"
@@ -378,7 +378,7 @@ static struct pci_driver mgag200_pci_driver = {
 
 static int __init mgag200_init(void)
 {
-	if (vgacon_text_force() && mgag200_modeset == -1)
+	if (!drm_get_modeset() && mgag200_modeset == -1)
 		return -EINVAL;
 
 	if (mgag200_modeset == 0)
diff --git drivers/gpu/drm/nouveau/nouveau_drm.c drivers/gpu/drm/nouveau/nouveau_drm.c
index 1f828c9f691c..d42e07de6460 100644
--- drivers/gpu/drm/nouveau/nouveau_drm.c
+++ drivers/gpu/drm/nouveau/nouveau_drm.c
@@ -22,7 +22,6 @@
  * Authors: Ben Skeggs
  */
 
-#include <linux/console.h>
 #include <linux/delay.h>
 #include <linux/module.h>
 #include <linux/pci.h>
@@ -34,6 +33,7 @@
 #include <drm/drm_crtc_helper.h>
 #include <drm/drm_gem_ttm_helper.h>
 #include <drm/drm_ioctl.h>
+#include <drm/drm_mode_config.h>
 #include <drm/drm_vblank.h>
 
 #include <core/gpuobj.h>
@@ -1322,7 +1322,7 @@ nouveau_drm_init(void)
 	nouveau_display_options();
 
 	if (nouveau_modeset == -1) {
-		if (vgacon_text_force())
+		if (!drm_get_modeset())
 			nouveau_modeset = 0;
 	}
 
diff --git drivers/gpu/drm/qxl/qxl_drv.c drivers/gpu/drm/qxl/qxl_drv.c
index fc47b0deb021..2d87a95ae431 100644
--- drivers/gpu/drm/qxl/qxl_drv.c
+++ drivers/gpu/drm/qxl/qxl_drv.c
@@ -29,7 +29,6 @@
 
 #include "qxl_drv.h"
 
-#include <linux/console.h>
 #include <linux/module.h>
 #include <linux/pci.h>
 #include <linux/vgaarb.h>
@@ -40,6 +39,7 @@
 #include <drm/drm_drv.h>
 #include <drm/drm_file.h>
 #include <drm/drm_gem_ttm_helper.h>
+#include <drm/drm_mode_config.h>
 #include <drm/drm_modeset_helper.h>
 #include <drm/drm_prime.h>
 #include <drm/drm_probe_helper.h>
@@ -295,7 +295,7 @@ static struct drm_driver qxl_driver = {
 
 static int __init qxl_init(void)
 {
-	if (vgacon_text_force() && qxl_modeset == -1)
+	if (!drm_get_modeset() && qxl_modeset == -1)
 		return -EINVAL;
 
 	if (qxl_modeset == 0)
diff --git drivers/gpu/drm/radeon/radeon_drv.c drivers/gpu/drm/radeon/radeon_drv.c
index 380adc61e71c..802a28d55d0a 100644
--- drivers/gpu/drm/radeon/radeon_drv.c
+++ drivers/gpu/drm/radeon/radeon_drv.c
@@ -31,7 +31,6 @@
 
 
 #include <linux/compat.h>
-#include <linux/console.h>
 #include <linux/module.h>
 #include <linux/pm_runtime.h>
 #include <linux/vga_switcheroo.h>
@@ -45,6 +44,7 @@
 #include <drm/drm_file.h>
 #include <drm/drm_gem.h>
 #include <drm/drm_ioctl.h>
+#include <drm/drm_mode_config.h>
 #include <drm/drm_pciids.h>
 #include <drm/drm_probe_helper.h>
 #include <drm/drm_vblank.h>
@@ -637,7 +637,7 @@ static struct pci_driver radeon_kms_pci_driver = {
 
 static int __init radeon_module_init(void)
 {
-	if (vgacon_text_force() && radeon_modeset == -1)
+	if (!drm_get_modeset() && radeon_modeset == -1)
 		radeon_modeset = 0;
 
 	if (radeon_modeset == 0)
diff --git drivers/gpu/drm/tiny/bochs.c drivers/gpu/drm/tiny/bochs.c
index 2ce3bd903b70..500101f8a6e9 100644
--- drivers/gpu/drm/tiny/bochs.c
+++ drivers/gpu/drm/tiny/bochs.c
@@ -1,6 +1,5 @@
 // SPDX-License-Identifier: GPL-2.0-or-later
 
-#include <linux/console.h>
 #include <linux/pci.h>
 
 #include <drm/drm_aperture.h>
@@ -11,6 +10,7 @@
 #include <drm/drm_gem_framebuffer_helper.h>
 #include <drm/drm_gem_vram_helper.h>
 #include <drm/drm_managed.h>
+#include <drm/drm_mode_config.h>
 #include <drm/drm_probe_helper.h>
 #include <drm/drm_simple_kms_helper.h>
 
@@ -719,7 +719,7 @@ static struct pci_driver bochs_pci_driver = {
 
 static int __init bochs_init(void)
 {
-	if (vgacon_text_force() && bochs_modeset == -1)
+	if (!drm_get_modeset() && bochs_modeset == -1)
 		return -EINVAL;
 
 	if (bochs_modeset == 0)
diff --git drivers/gpu/drm/tiny/cirrus.c drivers/gpu/drm/tiny/cirrus.c
index 4611ec408506..c94a030b6b3b 100644
--- drivers/gpu/drm/tiny/cirrus.c
+++ drivers/gpu/drm/tiny/cirrus.c
@@ -16,7 +16,6 @@
  * Copyright 1999-2001 Jeff Garzik <jgarzik@pobox.com>
  */
 
-#include <linux/console.h>
 #include <linux/dma-buf-map.h>
 #include <linux/module.h>
 #include <linux/pci.h>
@@ -39,6 +38,7 @@
 #include <drm/drm_gem_shmem_helper.h>
 #include <drm/drm_ioctl.h>
 #include <drm/drm_managed.h>
+#include <drm/drm_mode_config.h>
 #include <drm/drm_modeset_helper_vtables.h>
 #include <drm/drm_probe_helper.h>
 #include <drm/drm_simple_kms_helper.h>
@@ -636,8 +636,9 @@ static struct pci_driver cirrus_pci_driver = {
 
 static int __init cirrus_init(void)
 {
-	if (vgacon_text_force())
+	if (!drm_get_modeset())
 		return -EINVAL;
+
 	return pci_register_driver(&cirrus_pci_driver);
 }
 
diff --git drivers/gpu/drm/vboxvideo/vbox_drv.c drivers/gpu/drm/vboxvideo/vbox_drv.c
index fd7abb029c65..74b8c93a664f 100644
--- drivers/gpu/drm/vboxvideo/vbox_drv.c
+++ drivers/gpu/drm/vboxvideo/vbox_drv.c
@@ -7,7 +7,6 @@
  *          Michael Thayer <michael.thayer@oracle.com,
  *          Hans de Goede <hdegoede@redhat.com>
  */
-#include <linux/console.h>
 #include <linux/module.h>
 #include <linux/pci.h>
 #include <linux/vt_kern.h>
@@ -19,6 +18,7 @@
 #include <drm/drm_file.h>
 #include <drm/drm_ioctl.h>
 #include <drm/drm_managed.h>
+#include <drm/drm_mode_config.h>
 
 #include "vbox_drv.h"
 
@@ -193,7 +193,7 @@ static const struct drm_driver driver = {
 
 static int __init vbox_init(void)
 {
-	if (vgacon_text_force() && vbox_modeset == -1)
+	if (!drm_get_modeset() && vbox_modeset == -1)
 		return -EINVAL;
 
 	if (vbox_modeset == 0)
diff --git drivers/gpu/drm/virtio/virtgpu_drv.c drivers/gpu/drm/virtio/virtgpu_drv.c
index 749db18dcfa2..6ad20c225eed 100644
--- drivers/gpu/drm/virtio/virtgpu_drv.c
+++ drivers/gpu/drm/virtio/virtgpu_drv.c
@@ -27,7 +27,6 @@
  */
 
 #include <linux/module.h>
-#include <linux/console.h>
 #include <linux/pci.h>
 #include <linux/poll.h>
 #include <linux/wait.h>
@@ -37,6 +36,7 @@
 #include <drm/drm_atomic_helper.h>
 #include <drm/drm_drv.h>
 #include <drm/drm_file.h>
+#include <drm/drm_mode_config.h>
 
 #include "virtgpu_drv.h"
 
@@ -104,7 +104,7 @@ static int virtio_gpu_probe(struct virtio_device *vdev)
 	struct drm_device *dev;
 	int ret;
 
-	if (vgacon_text_force() && virtio_gpu_modeset == -1)
+	if (!drm_get_modeset() && virtio_gpu_modeset == -1)
 		return -EINVAL;
 
 	if (virtio_gpu_modeset == 0)
diff --git drivers/gpu/drm/vmwgfx/vmwgfx_drv.c drivers/gpu/drm/vmwgfx/vmwgfx_drv.c
index ab9a1750e1df..049fd017dca5 100644
--- drivers/gpu/drm/vmwgfx/vmwgfx_drv.c
+++ drivers/gpu/drm/vmwgfx/vmwgfx_drv.c
@@ -25,7 +25,6 @@
  *
  **************************************************************************/
 
-#include <linux/console.h>
 #include <linux/dma-mapping.h>
 #include <linux/module.h>
 #include <linux/pci.h>
@@ -34,6 +33,7 @@
 #include <drm/drm_aperture.h>
 #include <drm/drm_drv.h>
 #include <drm/drm_ioctl.h>
+#include <drm/drm_mode_config.h>
 #include <drm/drm_sysfs.h>
 #include <drm/ttm/ttm_bo_driver.h>
 #include <drm/ttm/ttm_range_manager.h>
@@ -1651,7 +1651,7 @@ static int __init vmwgfx_init(void)
 {
 	int ret;
 
-	if (vgacon_text_force())
+	if (!drm_get_modeset())
 		return -EINVAL;
 
 	ret = pci_register_driver(&vmw_pci_driver);
diff --git drivers/video/console/vgacon.c drivers/video/console/vgacon.c
index ef9c57ce0906..d4320b147956 100644
--- drivers/video/console/vgacon.c
+++ drivers/video/console/vgacon.c
@@ -97,30 +97,9 @@ static int 		vga_video_font_height;
 static int 		vga_scan_lines		__read_mostly;
 static unsigned int 	vga_rolled_over; /* last vc_origin offset before wrap */
 
-static bool vgacon_text_mode_force;
 static bool vga_hardscroll_enabled;
 static bool vga_hardscroll_user_enable = true;
 
-bool vgacon_text_force(void)
-{
-	return vgacon_text_mode_force;
-}
-EXPORT_SYMBOL(vgacon_text_force);
-
-static int __init text_mode(char *str)
-{
-	vgacon_text_mode_force = true;
-
-	pr_warn("You have booted with nomodeset. This means your GPU drivers are DISABLED\n");
-	pr_warn("Any video related functionality will be severely degraded, and you may not even be able to suspend the system properly\n");
-	pr_warn("Unless you actually understand what nomodeset does, you should reboot without enabling it\n");
-
-	return 1;
-}
-
-/* force text mode - used by kernel modesetting */
-__setup("nomodeset", text_mode);
-
 static int __init no_scroll(char *str)
 {
 	/*
diff --git include/drm/drm_mode_config.h include/drm/drm_mode_config.h
index 48b7de80daf5..f4d407908348 100644
--- include/drm/drm_mode_config.h
+++ include/drm/drm_mode_config.h
@@ -969,4 +969,10 @@ static inline int drm_mode_config_init(struct drm_device *dev)
 void drm_mode_config_reset(struct drm_device *dev);
 void drm_mode_config_cleanup(struct drm_device *dev);
 
+#ifdef CONFIG_VGA_CONSOLE
+extern bool drm_get_modeset(void);
+#else
+static inline bool drm_get_modeset(void) { return true; }
+#endif
+
 #endif
diff --git include/linux/console.h include/linux/console.h
index 20874db50bc8..d4dd8384898b 100644
--- include/linux/console.h
+++ include/linux/console.h
@@ -217,12 +217,6 @@ extern atomic_t ignore_console_lock_warning;
 #define VESA_HSYNC_SUSPEND      2
 #define VESA_POWERDOWN          3
 
-#ifdef CONFIG_VGA_CONSOLE
-extern bool vgacon_text_force(void);
-#else
-static inline bool vgacon_text_force(void) { return false; }
-#endif
-
 extern void console_init(void);
 
 /* For deferred console takeover */
-- 
2.33.1

[PATCH v3 3/6] drm: Move nomodeset kernel parameter to the DRM subsystem

[Javier Martinez Canillas]

The "nomodeset" kernel cmdline parameter is handled by the vgacon driver
but the exported vgacon_text_force() symbol is only used by DRM drivers.

It makes much more sense for the parameter logic to be in the subsystem
of the drivers that are making use of it.

Let's move the vgacon_text_force() function and related logic to the DRM
subsystem. While doing that, rename the function to drm_get_modeset() and
make it return true if modesetting is enabled and false otherwise. This
better reflects the condition that drivers are actually testing for.

Suggested-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
---

Changes in v3:
- Drop the drm_drv_enabled() function and just call to drm_get_modeset().
- Make drm_get_modeset() just a getter function and don't return an error.
- Move independent cleanups in drivers as separate preparatory patches.

Changes in v2:
- Conditionally build drm_nomodeset.o if CONFIG_VGA_CONSOLE is set.
- Squash patches to move nomodeset logic to DRM and do the renaming.
- Name the function drm_check_modeset() and make it return -ENODEV.
- Squash patch to add drm_drv_enabled() and make drivers use it.
- Make the drivers changes before moving nomodeset logic to DRM.
- Make drm_drv_enabled() return an errno and -ENODEV if nomodeset.
- Remove debug and error messages in drivers.

 drivers/gpu/drm/Makefile                |  2 ++
 drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c |  4 ++--
 drivers/gpu/drm/ast/ast_drv.c           |  4 ++--
 drivers/gpu/drm/drm_nomodeset.c         | 26 +++++++++++++++++++++++++
 drivers/gpu/drm/i915/i915_module.c      |  4 ++--
 drivers/gpu/drm/mgag200/mgag200_drv.c   |  4 ++--
 drivers/gpu/drm/nouveau/nouveau_drm.c   |  4 ++--
 drivers/gpu/drm/qxl/qxl_drv.c           |  4 ++--
 drivers/gpu/drm/radeon/radeon_drv.c     |  4 ++--
 drivers/gpu/drm/tiny/bochs.c            |  4 ++--
 drivers/gpu/drm/tiny/cirrus.c           |  5 +++--
 drivers/gpu/drm/vboxvideo/vbox_drv.c    |  4 ++--
 drivers/gpu/drm/virtio/virtgpu_drv.c    |  4 ++--
 drivers/gpu/drm/vmwgfx/vmwgfx_drv.c     |  4 ++--
 drivers/video/console/vgacon.c          | 21 --------------------
 include/drm/drm_mode_config.h           |  6 ++++++
 include/linux/console.h                 |  6 ------
 17 files changed, 59 insertions(+), 51 deletions(-)
 create mode 100644 drivers/gpu/drm/drm_nomodeset.c

diff --git drivers/gpu/drm/Makefile drivers/gpu/drm/Makefile
index 1c41156deb5f..c74810c285af 100644
--- drivers/gpu/drm/Makefile
+++ drivers/gpu/drm/Makefile
@@ -33,6 +33,8 @@ drm-$(CONFIG_DRM_PRIVACY_SCREEN) += drm_privacy_screen.o drm_privacy_screen_x86.
 
 obj-$(CONFIG_DRM_DP_AUX_BUS) += drm_dp_aux_bus.o
 
+obj-$(CONFIG_VGA_CONSOLE) += drm_nomodeset.o
+
 drm_cma_helper-y := drm_gem_cma_helper.o
 obj-$(CONFIG_DRM_GEM_CMA_HELPER) += drm_cma_helper.o
 
diff --git drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
index 289d04999ced..0da7f0b14700 100644
--- drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
+++ drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
@@ -28,10 +28,10 @@
 #include <drm/drm_gem.h>
 #include <drm/drm_vblank.h>
 #include <drm/drm_managed.h>
+#include <drm/drm_mode_config.h>
 #include "amdgpu_drv.h"
 
 #include <drm/drm_pciids.h>
-#include <linux/console.h>
 #include <linux/module.h>
 #include <linux/pm_runtime.h>
 #include <linux/vga_switcheroo.h>
@@ -2514,7 +2514,7 @@ static int __init amdgpu_init(void)
 {
 	int r;
 
-	if (vgacon_text_force())
+	if (!drm_get_modeset())
 		return -EINVAL;
 
 	r = amdgpu_sync_init();
diff --git drivers/gpu/drm/ast/ast_drv.c drivers/gpu/drm/ast/ast_drv.c
index 86d5cd7b6318..e788deac15cb 100644
--- drivers/gpu/drm/ast/ast_drv.c
+++ drivers/gpu/drm/ast/ast_drv.c
@@ -26,7 +26,6 @@
  * Authors: Dave Airlie <airlied@redhat.com>
  */
 
-#include <linux/console.h>
 #include <linux/module.h>
 #include <linux/pci.h>
 
@@ -35,6 +34,7 @@
 #include <drm/drm_crtc_helper.h>
 #include <drm/drm_drv.h>
 #include <drm/drm_gem_vram_helper.h>
+#include <drm/drm_mode_config.h>
 #include <drm/drm_probe_helper.h>
 
 #include "ast_drv.h"
@@ -233,7 +233,7 @@ static struct pci_driver ast_pci_driver = {
 
 static int __init ast_init(void)
 {
-	if (vgacon_text_force() && ast_modeset == -1)
+	if (!drm_get_modeset() && ast_modeset == -1)
 		return -EINVAL;
 
 	if (ast_modeset == 0)
diff --git drivers/gpu/drm/drm_nomodeset.c drivers/gpu/drm/drm_nomodeset.c
new file mode 100644
index 000000000000..fc3acf3ab2e2
--- /dev/null
+++ drivers/gpu/drm/drm_nomodeset.c
@@ -0,0 +1,26 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/module.h>
+#include <linux/types.h>
+
+static bool drm_nomodeset;
+
+bool drm_get_modeset(void)
+{
+	return !drm_nomodeset;
+}
+EXPORT_SYMBOL(drm_get_modeset);
+
+static int __init disable_modeset(char *str)
+{
+	drm_nomodeset = true;
+
+	pr_warn("You have booted with nomodeset. This means your GPU drivers are DISABLED\n");
+	pr_warn("Any video related functionality will be severely degraded, and you may not even be able to suspend the system properly\n");
+	pr_warn("Unless you actually understand what nomodeset does, you should reboot without enabling it\n");
+
+	return 1;
+}
+
+/* Disable kernel modesetting */
+__setup("nomodeset", disable_modeset);
diff --git drivers/gpu/drm/i915/i915_module.c drivers/gpu/drm/i915/i915_module.c
index ab2295dd4500..f952e8b69465 100644
--- drivers/gpu/drm/i915/i915_module.c
+++ drivers/gpu/drm/i915/i915_module.c
@@ -4,7 +4,7 @@
  * Copyright © 2021 Intel Corporation
  */
 
-#include <linux/console.h>
+#include <drm/drm_mode_config.h>
 
 #include "gem/i915_gem_context.h"
 #include "gem/i915_gem_object.h"
@@ -31,7 +31,7 @@ static int i915_check_nomodeset(void)
 	if (i915_modparams.modeset == 0)
 		use_kms = false;
 
-	if (vgacon_text_force() && i915_modparams.modeset == -1)
+	if (!drm_get_modeset() && i915_modparams.modeset == -1)
 		use_kms = false;
 
 	if (!use_kms) {
diff --git drivers/gpu/drm/mgag200/mgag200_drv.c drivers/gpu/drm/mgag200/mgag200_drv.c
index 6b9243713b3c..3df5a608d0e7 100644
--- drivers/gpu/drm/mgag200/mgag200_drv.c
+++ drivers/gpu/drm/mgag200/mgag200_drv.c
@@ -6,7 +6,6 @@
  *          Dave Airlie
  */
 
-#include <linux/console.h>
 #include <linux/module.h>
 #include <linux/pci.h>
 #include <linux/vmalloc.h>
@@ -15,6 +14,7 @@
 #include <drm/drm_drv.h>
 #include <drm/drm_file.h>
 #include <drm/drm_ioctl.h>
+#include <drm/drm_mode_config.h>
 #include <drm/drm_pciids.h>
 
 #include "mgag200_drv.h"
@@ -378,7 +378,7 @@ static struct pci_driver mgag200_pci_driver = {
 
 static int __init mgag200_init(void)
 {
-	if (vgacon_text_force() && mgag200_modeset == -1)
+	if (!drm_get_modeset() && mgag200_modeset == -1)
 		return -EINVAL;
 
 	if (mgag200_modeset == 0)
diff --git drivers/gpu/drm/nouveau/nouveau_drm.c drivers/gpu/drm/nouveau/nouveau_drm.c
index 1f828c9f691c..d42e07de6460 100644
--- drivers/gpu/drm/nouveau/nouveau_drm.c
+++ drivers/gpu/drm/nouveau/nouveau_drm.c
@@ -22,7 +22,6 @@
  * Authors: Ben Skeggs
  */
 
-#include <linux/console.h>
 #include <linux/delay.h>
 #include <linux/module.h>
 #include <linux/pci.h>
@@ -34,6 +33,7 @@
 #include <drm/drm_crtc_helper.h>
 #include <drm/drm_gem_ttm_helper.h>
 #include <drm/drm_ioctl.h>
+#include <drm/drm_mode_config.h>
 #include <drm/drm_vblank.h>
 
 #include <core/gpuobj.h>
@@ -1322,7 +1322,7 @@ nouveau_drm_init(void)
 	nouveau_display_options();
 
 	if (nouveau_modeset == -1) {
-		if (vgacon_text_force())
+		if (!drm_get_modeset())
 			nouveau_modeset = 0;
 	}
 
diff --git drivers/gpu/drm/qxl/qxl_drv.c drivers/gpu/drm/qxl/qxl_drv.c
index fc47b0deb021..2d87a95ae431 100644
--- drivers/gpu/drm/qxl/qxl_drv.c
+++ drivers/gpu/drm/qxl/qxl_drv.c
@@ -29,7 +29,6 @@
 
 #include "qxl_drv.h"
 
-#include <linux/console.h>
 #include <linux/module.h>
 #include <linux/pci.h>
 #include <linux/vgaarb.h>
@@ -40,6 +39,7 @@
 #include <drm/drm_drv.h>
 #include <drm/drm_file.h>
 #include <drm/drm_gem_ttm_helper.h>
+#include <drm/drm_mode_config.h>
 #include <drm/drm_modeset_helper.h>
 #include <drm/drm_prime.h>
 #include <drm/drm_probe_helper.h>
@@ -295,7 +295,7 @@ static struct drm_driver qxl_driver = {
 
 static int __init qxl_init(void)
 {
-	if (vgacon_text_force() && qxl_modeset == -1)
+	if (!drm_get_modeset() && qxl_modeset == -1)
 		return -EINVAL;
 
 	if (qxl_modeset == 0)
diff --git drivers/gpu/drm/radeon/radeon_drv.c drivers/gpu/drm/radeon/radeon_drv.c
index 380adc61e71c..802a28d55d0a 100644
--- drivers/gpu/drm/radeon/radeon_drv.c
+++ drivers/gpu/drm/radeon/radeon_drv.c
@@ -31,7 +31,6 @@
 
 
 #include <linux/compat.h>
-#include <linux/console.h>
 #include <linux/module.h>
 #include <linux/pm_runtime.h>
 #include <linux/vga_switcheroo.h>
@@ -45,6 +44,7 @@
 #include <drm/drm_file.h>
 #include <drm/drm_gem.h>
 #include <drm/drm_ioctl.h>
+#include <drm/drm_mode_config.h>
 #include <drm/drm_pciids.h>
 #include <drm/drm_probe_helper.h>
 #include <drm/drm_vblank.h>
@@ -637,7 +637,7 @@ static struct pci_driver radeon_kms_pci_driver = {
 
 static int __init radeon_module_init(void)
 {
-	if (vgacon_text_force() && radeon_modeset == -1)
+	if (!drm_get_modeset() && radeon_modeset == -1)
 		radeon_modeset = 0;
 
 	if (radeon_modeset == 0)
diff --git drivers/gpu/drm/tiny/bochs.c drivers/gpu/drm/tiny/bochs.c
index 2ce3bd903b70..500101f8a6e9 100644
--- drivers/gpu/drm/tiny/bochs.c
+++ drivers/gpu/drm/tiny/bochs.c
@@ -1,6 +1,5 @@
 // SPDX-License-Identifier: GPL-2.0-or-later
 
-#include <linux/console.h>
 #include <linux/pci.h>
 
 #include <drm/drm_aperture.h>
@@ -11,6 +10,7 @@
 #include <drm/drm_gem_framebuffer_helper.h>
 #include <drm/drm_gem_vram_helper.h>
 #include <drm/drm_managed.h>
+#include <drm/drm_mode_config.h>
 #include <drm/drm_probe_helper.h>
 #include <drm/drm_simple_kms_helper.h>
 
@@ -719,7 +719,7 @@ static struct pci_driver bochs_pci_driver = {
 
 static int __init bochs_init(void)
 {
-	if (vgacon_text_force() && bochs_modeset == -1)
+	if (!drm_get_modeset() && bochs_modeset == -1)
 		return -EINVAL;
 
 	if (bochs_modeset == 0)
diff --git drivers/gpu/drm/tiny/cirrus.c drivers/gpu/drm/tiny/cirrus.c
index 4611ec408506..c94a030b6b3b 100644
--- drivers/gpu/drm/tiny/cirrus.c
+++ drivers/gpu/drm/tiny/cirrus.c
@@ -16,7 +16,6 @@
  * Copyright 1999-2001 Jeff Garzik <jgarzik@pobox.com>
  */
 
-#include <linux/console.h>
 #include <linux/dma-buf-map.h>
 #include <linux/module.h>
 #include <linux/pci.h>
@@ -39,6 +38,7 @@
 #include <drm/drm_gem_shmem_helper.h>
 #include <drm/drm_ioctl.h>
 #include <drm/drm_managed.h>
+#include <drm/drm_mode_config.h>
 #include <drm/drm_modeset_helper_vtables.h>
 #include <drm/drm_probe_helper.h>
 #include <drm/drm_simple_kms_helper.h>
@@ -636,8 +636,9 @@ static struct pci_driver cirrus_pci_driver = {
 
 static int __init cirrus_init(void)
 {
-	if (vgacon_text_force())
+	if (!drm_get_modeset())
 		return -EINVAL;
+
 	return pci_register_driver(&cirrus_pci_driver);
 }
 
diff --git drivers/gpu/drm/vboxvideo/vbox_drv.c drivers/gpu/drm/vboxvideo/vbox_drv.c
index fd7abb029c65..74b8c93a664f 100644
--- drivers/gpu/drm/vboxvideo/vbox_drv.c
+++ drivers/gpu/drm/vboxvideo/vbox_drv.c
@@ -7,7 +7,6 @@
  *          Michael Thayer <michael.thayer@oracle.com,
  *          Hans de Goede <hdegoede@redhat.com>
  */
-#include <linux/console.h>
 #include <linux/module.h>
 #include <linux/pci.h>
 #include <linux/vt_kern.h>
@@ -19,6 +18,7 @@
 #include <drm/drm_file.h>
 #include <drm/drm_ioctl.h>
 #include <drm/drm_managed.h>
+#include <drm/drm_mode_config.h>
 
 #include "vbox_drv.h"
 
@@ -193,7 +193,7 @@ static const struct drm_driver driver = {
 
 static int __init vbox_init(void)
 {
-	if (vgacon_text_force() && vbox_modeset == -1)
+	if (!drm_get_modeset() && vbox_modeset == -1)
 		return -EINVAL;
 
 	if (vbox_modeset == 0)
diff --git drivers/gpu/drm/virtio/virtgpu_drv.c drivers/gpu/drm/virtio/virtgpu_drv.c
index 749db18dcfa2..6ad20c225eed 100644
--- drivers/gpu/drm/virtio/virtgpu_drv.c
+++ drivers/gpu/drm/virtio/virtgpu_drv.c
@@ -27,7 +27,6 @@
  */
 
 #include <linux/module.h>
-#include <linux/console.h>
 #include <linux/pci.h>
 #include <linux/poll.h>
 #include <linux/wait.h>
@@ -37,6 +36,7 @@
 #include <drm/drm_atomic_helper.h>
 #include <drm/drm_drv.h>
 #include <drm/drm_file.h>
+#include <drm/drm_mode_config.h>
 
 #include "virtgpu_drv.h"
 
@@ -104,7 +104,7 @@ static int virtio_gpu_probe(struct virtio_device *vdev)
 	struct drm_device *dev;
 	int ret;
 
-	if (vgacon_text_force() && virtio_gpu_modeset == -1)
+	if (!drm_get_modeset() && virtio_gpu_modeset == -1)
 		return -EINVAL;
 
 	if (virtio_gpu_modeset == 0)
diff --git drivers/gpu/drm/vmwgfx/vmwgfx_drv.c drivers/gpu/drm/vmwgfx/vmwgfx_drv.c
index ab9a1750e1df..049fd017dca5 100644
--- drivers/gpu/drm/vmwgfx/vmwgfx_drv.c
+++ drivers/gpu/drm/vmwgfx/vmwgfx_drv.c
@@ -25,7 +25,6 @@
  *
  **************************************************************************/
 
-#include <linux/console.h>
 #include <linux/dma-mapping.h>
 #include <linux/module.h>
 #include <linux/pci.h>
@@ -34,6 +33,7 @@
 #include <drm/drm_aperture.h>
 #include <drm/drm_drv.h>
 #include <drm/drm_ioctl.h>
+#include <drm/drm_mode_config.h>
 #include <drm/drm_sysfs.h>
 #include <drm/ttm/ttm_bo_driver.h>
 #include <drm/ttm/ttm_range_manager.h>
@@ -1651,7 +1651,7 @@ static int __init vmwgfx_init(void)
 {
 	int ret;
 
-	if (vgacon_text_force())
+	if (!drm_get_modeset())
 		return -EINVAL;
 
 	ret = pci_register_driver(&vmw_pci_driver);
diff --git drivers/video/console/vgacon.c drivers/video/console/vgacon.c
index ef9c57ce0906..d4320b147956 100644
--- drivers/video/console/vgacon.c
+++ drivers/video/console/vgacon.c
@@ -97,30 +97,9 @@ static int 		vga_video_font_height;
 static int 		vga_scan_lines		__read_mostly;
 static unsigned int 	vga_rolled_over; /* last vc_origin offset before wrap */
 
-static bool vgacon_text_mode_force;
 static bool vga_hardscroll_enabled;
 static bool vga_hardscroll_user_enable = true;
 
-bool vgacon_text_force(void)
-{
-	return vgacon_text_mode_force;
-}
-EXPORT_SYMBOL(vgacon_text_force);
-
-static int __init text_mode(char *str)
-{
-	vgacon_text_mode_force = true;
-
-	pr_warn("You have booted with nomodeset. This means your GPU drivers are DISABLED\n");
-	pr_warn("Any video related functionality will be severely degraded, and you may not even be able to suspend the system properly\n");
-	pr_warn("Unless you actually understand what nomodeset does, you should reboot without enabling it\n");
-
-	return 1;
-}
-
-/* force text mode - used by kernel modesetting */
-__setup("nomodeset", text_mode);
-
 static int __init no_scroll(char *str)
 {
 	/*
diff --git include/drm/drm_mode_config.h include/drm/drm_mode_config.h
index 48b7de80daf5..f4d407908348 100644
--- include/drm/drm_mode_config.h
+++ include/drm/drm_mode_config.h
@@ -969,4 +969,10 @@ static inline int drm_mode_config_init(struct drm_device *dev)
 void drm_mode_config_reset(struct drm_device *dev);
 void drm_mode_config_cleanup(struct drm_device *dev);
 
+#ifdef CONFIG_VGA_CONSOLE
+extern bool drm_get_modeset(void);
+#else
+static inline bool drm_get_modeset(void) { return true; }
+#endif
+
 #endif
diff --git include/linux/console.h include/linux/console.h
index 20874db50bc8..d4dd8384898b 100644
--- include/linux/console.h
+++ include/linux/console.h
@@ -217,12 +217,6 @@ extern atomic_t ignore_console_lock_warning;
 #define VESA_HSYNC_SUSPEND      2
 #define VESA_POWERDOWN          3
 
-#ifdef CONFIG_VGA_CONSOLE
-extern bool vgacon_text_force(void);
-#else
-static inline bool vgacon_text_force(void) { return false; }
-#endif
-
 extern void console_init(void);
 
 /* For deferred console takeover */
-- 
2.33.1

[PATCH v3 4/6] drm: Decouple nomodeset from CONFIG_VGA_CONSOLE

[Javier Martinez Canillas]

This relationship was only for historical reasons and the nomodeset option
should be available even on platforms that don't enable CONFIG_VGA_CONSOLE.

Suggested-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
---

(no changes since v1)

 drivers/gpu/drm/Kconfig       | 6 ++++++
 drivers/gpu/drm/Makefile      | 2 +-
 include/drm/drm_mode_config.h | 4 ----
 3 files changed, 7 insertions(+), 5 deletions(-)

diff --git drivers/gpu/drm/Kconfig drivers/gpu/drm/Kconfig
index fb144617055b..483d534eb074 100644
--- drivers/gpu/drm/Kconfig
+++ drivers/gpu/drm/Kconfig
@@ -8,6 +8,7 @@
 menuconfig DRM
 	tristate "Direct Rendering Manager (XFree86 4.1.0 and higher DRI support)"
 	depends on (AGP || AGP=n) && !EMULATED_CMPXCHG && HAS_DMA
+	select DRM_NOMODESET
 	select DRM_PANEL_ORIENTATION_QUIRKS
 	select HDMI
 	select FB_CMDLINE
@@ -493,6 +494,11 @@ config DRM_EXPORT_FOR_TESTS
 config DRM_PANEL_ORIENTATION_QUIRKS
 	tristate
 
+# Separate option because nomodeset parameter is global and expected built-in
+config DRM_NOMODESET
+	bool
+	default n
+
 config DRM_LIB_RANDOM
 	bool
 	default n
diff --git drivers/gpu/drm/Makefile drivers/gpu/drm/Makefile
index c74810c285af..fa16d3e0bbdc 100644
--- drivers/gpu/drm/Makefile
+++ drivers/gpu/drm/Makefile
@@ -33,7 +33,7 @@ drm-$(CONFIG_DRM_PRIVACY_SCREEN) += drm_privacy_screen.o drm_privacy_screen_x86.
 
 obj-$(CONFIG_DRM_DP_AUX_BUS) += drm_dp_aux_bus.o
 
-obj-$(CONFIG_VGA_CONSOLE) += drm_nomodeset.o
+obj-$(CONFIG_DRM_NOMODESET) += drm_nomodeset.o
 
 drm_cma_helper-y := drm_gem_cma_helper.o
 obj-$(CONFIG_DRM_GEM_CMA_HELPER) += drm_cma_helper.o
diff --git include/drm/drm_mode_config.h include/drm/drm_mode_config.h
index f4d407908348..4bb129040185 100644
--- include/drm/drm_mode_config.h
+++ include/drm/drm_mode_config.h
@@ -969,10 +969,6 @@ static inline int drm_mode_config_init(struct drm_device *dev)
 void drm_mode_config_reset(struct drm_device *dev);
 void drm_mode_config_cleanup(struct drm_device *dev);
 
-#ifdef CONFIG_VGA_CONSOLE
 extern bool drm_get_modeset(void);
-#else
-static inline bool drm_get_modeset(void) { return true; }
-#endif
 
 #endif
-- 
2.33.1

[PATCH v3 4/6] drm: Decouple nomodeset from CONFIG_VGA_CONSOLE

[Javier Martinez Canillas]

This relationship was only for historical reasons and the nomodeset option
should be available even on platforms that don't enable CONFIG_VGA_CONSOLE.

Suggested-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
---

(no changes since v1)

 drivers/gpu/drm/Kconfig       | 6 ++++++
 drivers/gpu/drm/Makefile      | 2 +-
 include/drm/drm_mode_config.h | 4 ----
 3 files changed, 7 insertions(+), 5 deletions(-)

diff --git drivers/gpu/drm/Kconfig drivers/gpu/drm/Kconfig
index fb144617055b..483d534eb074 100644
--- drivers/gpu/drm/Kconfig
+++ drivers/gpu/drm/Kconfig
@@ -8,6 +8,7 @@
 menuconfig DRM
 	tristate "Direct Rendering Manager (XFree86 4.1.0 and higher DRI support)"
 	depends on (AGP || AGP=n) && !EMULATED_CMPXCHG && HAS_DMA
+	select DRM_NOMODESET
 	select DRM_PANEL_ORIENTATION_QUIRKS
 	select HDMI
 	select FB_CMDLINE
@@ -493,6 +494,11 @@ config DRM_EXPORT_FOR_TESTS
 config DRM_PANEL_ORIENTATION_QUIRKS
 	tristate
 
+# Separate option because nomodeset parameter is global and expected built-in
+config DRM_NOMODESET
+	bool
+	default n
+
 config DRM_LIB_RANDOM
 	bool
 	default n
diff --git drivers/gpu/drm/Makefile drivers/gpu/drm/Makefile
index c74810c285af..fa16d3e0bbdc 100644
--- drivers/gpu/drm/Makefile
+++ drivers/gpu/drm/Makefile
@@ -33,7 +33,7 @@ drm-$(CONFIG_DRM_PRIVACY_SCREEN) += drm_privacy_screen.o drm_privacy_screen_x86.
 
 obj-$(CONFIG_DRM_DP_AUX_BUS) += drm_dp_aux_bus.o
 
-obj-$(CONFIG_VGA_CONSOLE) += drm_nomodeset.o
+obj-$(CONFIG_DRM_NOMODESET) += drm_nomodeset.o
 
 drm_cma_helper-y := drm_gem_cma_helper.o
 obj-$(CONFIG_DRM_GEM_CMA_HELPER) += drm_cma_helper.o
diff --git include/drm/drm_mode_config.h include/drm/drm_mode_config.h
index f4d407908348..4bb129040185 100644
--- include/drm/drm_mode_config.h
+++ include/drm/drm_mode_config.h
@@ -969,10 +969,6 @@ static inline int drm_mode_config_init(struct drm_device *dev)
 void drm_mode_config_reset(struct drm_device *dev);
 void drm_mode_config_cleanup(struct drm_device *dev);
 
-#ifdef CONFIG_VGA_CONSOLE
 extern bool drm_get_modeset(void);
-#else
-static inline bool drm_get_modeset(void) { return true; }
-#endif
 
 #endif
-- 
2.33.1

[PATCH v3 5/6] Documentation/admin-guide: Document nomodeset kernel parameter

[Javier Martinez Canillas]

The nomodeset kernel command line parameter is not documented. Its name
is quite vague and is not intuitive what's the behaviour when it is set.

Document in kernel-parameters.txt what actually happens when nomodeset
is used. That way, users could know if they want to enable this option.

Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
---

(no changes since v1)

 Documentation/admin-guide/kernel-parameters.txt | 4 ++++
 1 file changed, 4 insertions(+)

diff --git Documentation/admin-guide/kernel-parameters.txt Documentation/admin-guide/kernel-parameters.txt
index 91ba391f9b32..ed9859fd0734 100644
--- Documentation/admin-guide/kernel-parameters.txt
+++ Documentation/admin-guide/kernel-parameters.txt
@@ -3521,6 +3521,10 @@
 			shutdown the other cpus.  Instead use the REBOOT_VECTOR
 			irq.
 
+	nomodeset	Disable kernel modesetting. DRM drivers will not be
+			loaded when this kernel boot parameter is used. The
+			simpledrm driver is the only DRM driver that loads.
+
 	nomodule	Disable module load
 
 	nopat		[X86] Disable PAT (page attribute table extension of
-- 
2.33.1

[PATCH v3 5/6] Documentation/admin-guide: Document nomodeset kernel parameter

[Javier Martinez Canillas]

The nomodeset kernel command line parameter is not documented. Its name
is quite vague and is not intuitive what's the behaviour when it is set.

Document in kernel-parameters.txt what actually happens when nomodeset
is used. That way, users could know if they want to enable this option.

Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
---

(no changes since v1)

 Documentation/admin-guide/kernel-parameters.txt | 4 ++++
 1 file changed, 4 insertions(+)

diff --git Documentation/admin-guide/kernel-parameters.txt Documentation/admin-guide/kernel-parameters.txt
index 91ba391f9b32..ed9859fd0734 100644
--- Documentation/admin-guide/kernel-parameters.txt
+++ Documentation/admin-guide/kernel-parameters.txt
@@ -3521,6 +3521,10 @@
 			shutdown the other cpus.  Instead use the REBOOT_VECTOR
 			irq.
 
+	nomodeset	Disable kernel modesetting. DRM drivers will not be
+			loaded when this kernel boot parameter is used. The
+			simpledrm driver is the only DRM driver that loads.
+
 	nomodule	Disable module load
 
 	nopat		[X86] Disable PAT (page attribute table extension of
-- 
2.33.1

[PATCH v3 6/6] drm: Make the nomodeset message less sensational

[Javier Martinez Canillas]

The message printed when nomodeset is present in the kernel command line
makes it look as if the parameter must never be used and it's a bad idea.

But there are valid reasons to use this parameter and the message should
not imply otherwise. Change the text to be more accurate and restrained.

Suggested-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
---

(no changes since v1)

 drivers/gpu/drm/drm_nomodeset.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git drivers/gpu/drm/drm_nomodeset.c drivers/gpu/drm/drm_nomodeset.c
index fc3acf3ab2e2..45e50b3497b8 100644
--- drivers/gpu/drm/drm_nomodeset.c
+++ drivers/gpu/drm/drm_nomodeset.c
@@ -15,9 +15,7 @@ static int __init disable_modeset(char *str)
 {
 	drm_nomodeset = true;
 
-	pr_warn("You have booted with nomodeset. This means your GPU drivers are DISABLED\n");
-	pr_warn("Any video related functionality will be severely degraded, and you may not even be able to suspend the system properly\n");
-	pr_warn("Unless you actually understand what nomodeset does, you should reboot without enabling it\n");
+	pr_warn("Booted with the nomodeset parameter. Graphics drivers will not be loaded\n");
 
 	return 1;
 }
-- 
2.33.1

[PATCH v3 6/6] drm: Make the nomodeset message less sensational

[Javier Martinez Canillas]

The message printed when nomodeset is present in the kernel command line
makes it look as if the parameter must never be used and it's a bad idea.

But there are valid reasons to use this parameter and the message should
not imply otherwise. Change the text to be more accurate and restrained.

Suggested-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
---

(no changes since v1)

 drivers/gpu/drm/drm_nomodeset.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git drivers/gpu/drm/drm_nomodeset.c drivers/gpu/drm/drm_nomodeset.c
index fc3acf3ab2e2..45e50b3497b8 100644
--- drivers/gpu/drm/drm_nomodeset.c
+++ drivers/gpu/drm/drm_nomodeset.c
@@ -15,9 +15,7 @@ static int __init disable_modeset(char *str)
 {
 	drm_nomodeset = true;
 
-	pr_warn("You have booted with nomodeset. This means your GPU drivers are DISABLED\n");
-	pr_warn("Any video related functionality will be severely degraded, and you may not even be able to suspend the system properly\n");
-	pr_warn("Unless you actually understand what nomodeset does, you should reboot without enabling it\n");
+	pr_warn("Booted with the nomodeset parameter. Graphics drivers will not be loaded\n");
 
 	return 1;
 }
-- 
2.33.1

Re: [PATCH v3 5/6] Documentation/admin-guide: Document nomodeset kernel parameter

[Thomas Zimmermann]

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Hi

Am 08.11.21 um 13:15 schrieb Javier Martinez Canillas:
> The nomodeset kernel command line parameter is not documented. Its name
> is quite vague and is not intuitive what's the behaviour when it is set.
> 
> Document in kernel-parameters.txt what actually happens when nomodeset
> is used. That way, users could know if they want to enable this option.
> 
> Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
> ---
> 
> (no changes since v1)
> 
>   Documentation/admin-guide/kernel-parameters.txt | 4 ++++
>   1 file changed, 4 insertions(+)
> 
> diff --git Documentation/admin-guide/kernel-parameters.txt Documentation/admin-guide/kernel-parameters.txt
> index 91ba391f9b32..ed9859fd0734 100644
> --- Documentation/admin-guide/kernel-parameters.txt
> +++ Documentation/admin-guide/kernel-parameters.txt
> @@ -3521,6 +3521,10 @@
>   			shutdown the other cpus.  Instead use the REBOOT_VECTOR
>   			irq.
>   
> +	nomodeset	Disable kernel modesetting. DRM drivers will not be
> +			loaded when this kernel boot parameter is used. The
> +			simpledrm driver is the only DRM driver that loads.
> +

That's misleading and to the general admin it might not be clear what 
simpledrm is about. Rather say something like

  Disable kernel modesetting. DRM drivers will not perform
  display-mode changes or accelerated rendering. Only the
  system framebuffer will be available for use. Requires the
  firmware or boot loader to setup the display. Useful as
  fallback, or for testing and debugging.

Best regards
Thomas

>   	nomodule	Disable module load
>   
>   	nopat		[X86] Disable PAT (page attribute table extension of
> 

-- 
Thomas Zimmermann
Graphics Driver Developer
SUSE Software Solutions Germany GmbH
Maxfeldstr. 5, 90409 Nürnberg, Germany
(HRB 36809, AG Nürnberg)
Geschäftsführer: Ivo Totev

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Re: [PATCH v3 5/6] Documentation/admin-guide: Document nomodeset kernel parameter

[Thomas Zimmermann]

[-- Attachment #1.1: Type: text/plain, Size: 1871 bytes --]

Hi

Am 08.11.21 um 13:15 schrieb Javier Martinez Canillas:
> The nomodeset kernel command line parameter is not documented. Its name
> is quite vague and is not intuitive what's the behaviour when it is set.
> 
> Document in kernel-parameters.txt what actually happens when nomodeset
> is used. That way, users could know if they want to enable this option.
> 
> Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
> ---
> 
> (no changes since v1)
> 
>   Documentation/admin-guide/kernel-parameters.txt | 4 ++++
>   1 file changed, 4 insertions(+)
> 
> diff --git Documentation/admin-guide/kernel-parameters.txt Documentation/admin-guide/kernel-parameters.txt
> index 91ba391f9b32..ed9859fd0734 100644
> --- Documentation/admin-guide/kernel-parameters.txt
> +++ Documentation/admin-guide/kernel-parameters.txt
> @@ -3521,6 +3521,10 @@
>   			shutdown the other cpus.  Instead use the REBOOT_VECTOR
>   			irq.
>   
> +	nomodeset	Disable kernel modesetting. DRM drivers will not be
> +			loaded when this kernel boot parameter is used. The
> +			simpledrm driver is the only DRM driver that loads.
> +

That's misleading and to the general admin it might not be clear what 
simpledrm is about. Rather say something like

  Disable kernel modesetting. DRM drivers will not perform
  display-mode changes or accelerated rendering. Only the
  system framebuffer will be available for use. Requires the
  firmware or boot loader to setup the display. Useful as
  fallback, or for testing and debugging.

Best regards
Thomas

>   	nomodule	Disable module load
>   
>   	nopat		[X86] Disable PAT (page attribute table extension of
> 

-- 
Thomas Zimmermann
Graphics Driver Developer
SUSE Software Solutions Germany GmbH
Maxfeldstr. 5, 90409 Nürnberg, Germany
(HRB 36809, AG Nürnberg)
Geschäftsführer: Ivo Totev

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Re: [PATCH v3 6/6] drm: Make the nomodeset message less sensational

[Thomas Zimmermann]

[-- Attachment #1.1: Type: text/plain, Size: 1772 bytes --]

Hi

Am 08.11.21 um 13:15 schrieb Javier Martinez Canillas:
> The message printed when nomodeset is present in the kernel command line
> makes it look as if the parameter must never be used and it's a bad idea.
> 
> But there are valid reasons to use this parameter and the message should
> not imply otherwise. Change the text to be more accurate and restrained.
> 
> Suggested-by: Thomas Zimmermann <tzimmermann@suse.de>
> Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
> ---
> 
> (no changes since v1)
> 
>   drivers/gpu/drm/drm_nomodeset.c | 4 +---
>   1 file changed, 1 insertion(+), 3 deletions(-)
> 
> diff --git drivers/gpu/drm/drm_nomodeset.c drivers/gpu/drm/drm_nomodeset.c
> index fc3acf3ab2e2..45e50b3497b8 100644
> --- drivers/gpu/drm/drm_nomodeset.c
> +++ drivers/gpu/drm/drm_nomodeset.c
> @@ -15,9 +15,7 @@ static int __init disable_modeset(char *str)
>   {
>   	drm_nomodeset = true;
>   
> -	pr_warn("You have booted with nomodeset. This means your GPU drivers are DISABLED\n");
> -	pr_warn("Any video related functionality will be severely degraded, and you may not even be able to suspend the system properly\n");
> -	pr_warn("Unless you actually understand what nomodeset does, you should reboot without enabling it\n");
> +	pr_warn("Booted with the nomodeset parameter. Graphics drivers will not be loaded\n");

Same issue as with patch 5. Rather say something like

   Booted with the nomodeset parameter. Only the system framebuffer will 
be available.

Best regards
Thomas

>   
>   	return 1;
>   }
> 

-- 
Thomas Zimmermann
Graphics Driver Developer
SUSE Software Solutions Germany GmbH
Maxfeldstr. 5, 90409 Nürnberg, Germany
(HRB 36809, AG Nürnberg)
Geschäftsführer: Ivo Totev

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Re: [PATCH v3 0/6] Cleanups for the nomodeset kernel command line parameter logic

[Thomas Zimmermann]

[-- Attachment #1.1: Type: text/plain, Size: 4368 bytes --]

Hi

Am 08.11.21 um 13:15 schrieb Javier Martinez Canillas:
> There is a lot of historical baggage on this parameter. It is defined in
> the vgacon driver as nomodeset, but its set function is called text_mode()
> and the value queried with a function named vgacon_text_force().
> 
> All this implies that it's about forcing text mode for VGA, yet it is not
> used in neither vgacon nor other console driver. The only users for these
> are DRM drivers, that check for the vgacon_text_force() return value to
> determine whether the driver should be loaded or not.
> 
> That makes it quite confusing to read the code, because the variables and
> function names don't reflect what they actually do and also are not in the
> same subsystem as the drivers that make use of them.
> 
> This patch-set attempts to cleanup the code by moving the nomodseset param
> to the DRM subsystem and do some renaming to make their intention clearer.
> 
> This is a v3 of the patches, that address issues pointed out by Jani Nikula
> in v2: https://lkml.org/lkml/2021/11/4/594
> 
> Patch #1 and #2 are just trivial cleanups.
> 
> Patch #3 moves the nomodeset boot option to the DRM subsystem and renames
> the variables and functions names.
> 
> Patch #4 removes the relationship between the nomodeset parameter and the
> CONFIG_VGA_CONSOLE Kconfig symbol.

On patches 1 to 4

Acked-by: Thomas Zimmermann <tzimmermann@suse.de>

> 
> Patch #5 adds nomodeset to the kernel parameters documentation.
> 
> Patch #6 improves the message when nomodeset is enabled to make it more
> accurate and less sensational.

See my comments on these patches.

Best regards
Thomas

> 
> Changes in v3:
> - Drop the drm_drv_enabled() function and just call to drm_get_modeset().
> - Make drm_get_modeset() just a getter function and don't return an error.
> - Move independent cleanups in drivers as separate preparatory patches.
> 
> Changes in v2:
> - Conditionally build drm_nomodeset.o if CONFIG_VGA_CONSOLE is set.
> - Squash patches to move nomodeset logic to DRM and do the renaming.
> - Name the function drm_check_modeset() and make it return -ENODEV.
> - Squash patch to add drm_drv_enabled() and make drivers use it.
> - Make the drivers changes before moving nomodeset logic to DRM.
> - Make drm_drv_enabled() return an errno and -ENODEV if nomodeset.
> - Remove debug and error messages in drivers.
> 
> Javier Martinez Canillas (6):
>    drm: Don't print messages if drivers are disabled due nomodeset
>    drm/vboxvideo: Drop CONFIG_VGA_CONSOLE guard to call
>      vgacon_text_force()
>    drm: Move nomodeset kernel parameter to the DRM subsystem
>    drm: Decouple nomodeset from CONFIG_VGA_CONSOLE
>    Documentation/admin-guide: Document nomodeset kernel parameter
>    drm: Make the nomodeset message less sensational
> 
>   .../admin-guide/kernel-parameters.txt         |  4 ++++
>   drivers/gpu/drm/Kconfig                       |  6 +++++
>   drivers/gpu/drm/Makefile                      |  2 ++
>   drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c       |  6 ++---
>   drivers/gpu/drm/ast/ast_drv.c                 |  4 ++--
>   drivers/gpu/drm/drm_nomodeset.c               | 24 +++++++++++++++++++
>   drivers/gpu/drm/i915/i915_module.c            |  4 ++--
>   drivers/gpu/drm/mgag200/mgag200_drv.c         |  4 ++--
>   drivers/gpu/drm/nouveau/nouveau_drm.c         |  4 ++--
>   drivers/gpu/drm/qxl/qxl_drv.c                 |  4 ++--
>   drivers/gpu/drm/radeon/radeon_drv.c           | 10 +++-----
>   drivers/gpu/drm/tiny/bochs.c                  |  4 ++--
>   drivers/gpu/drm/tiny/cirrus.c                 |  5 ++--
>   drivers/gpu/drm/vboxvideo/vbox_drv.c          |  6 ++---
>   drivers/gpu/drm/virtio/virtgpu_drv.c          |  4 ++--
>   drivers/gpu/drm/vmwgfx/vmwgfx_drv.c           |  4 ++--
>   drivers/video/console/vgacon.c                | 21 ----------------
>   include/drm/drm_mode_config.h                 |  2 ++
>   include/linux/console.h                       |  6 -----
>   19 files changed, 64 insertions(+), 60 deletions(-)
>   create mode 100644 drivers/gpu/drm/drm_nomodeset.c
> 

-- 
Thomas Zimmermann
Graphics Driver Developer
SUSE Software Solutions Germany GmbH
Maxfeldstr. 5, 90409 Nürnberg, Germany
(HRB 36809, AG Nürnberg)
Geschäftsführer: Ivo Totev

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Re: [PATCH v3 0/6] Cleanups for the nomodeset kernel command line parameter logic

[Javier Martinez Canillas]

Hello Thomas,

On 11/8/21 13:50, Thomas Zimmermann wrote:
> Hi
> 
> Am 08.11.21 um 13:15 schrieb Javier Martinez Canillas:
>> There is a lot of historical baggage on this parameter. It is defined in
>> the vgacon driver as nomodeset, but its set function is called text_mode()
>> and the value queried with a function named vgacon_text_force().
>>
>> All this implies that it's about forcing text mode for VGA, yet it is not
>> used in neither vgacon nor other console driver. The only users for these
>> are DRM drivers, that check for the vgacon_text_force() return value to
>> determine whether the driver should be loaded or not.
>>
>> That makes it quite confusing to read the code, because the variables and
>> function names don't reflect what they actually do and also are not in the
>> same subsystem as the drivers that make use of them.
>>
>> This patch-set attempts to cleanup the code by moving the nomodseset param
>> to the DRM subsystem and do some renaming to make their intention clearer.
>>
>> This is a v3 of the patches, that address issues pointed out by Jani Nikula
>> in v2: https://lkml.org/lkml/2021/11/4/594
>>
>> Patch #1 and #2 are just trivial cleanups.
>>
>> Patch #3 moves the nomodeset boot option to the DRM subsystem and renames
>> the variables and functions names.
>>
>> Patch #4 removes the relationship between the nomodeset parameter and the
>> CONFIG_VGA_CONSOLE Kconfig symbol.
> 
> On patches 1 to 4
> 
> Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
>

Thanks!
 
>>
>> Patch #5 adds nomodeset to the kernel parameters documentation.
>>
>> Patch #6 improves the message when nomodeset is enabled to make it more
>> accurate and less sensational.
> 
> See my comments on these patches.
>

Yes, agreed with your feedback on these. I'll improve it when posting a v4.

Best regards, -- 
Javier Martinez Canillas
Linux Engineering
Red Hat

Re: [PATCH v3 5/6] Documentation/admin-guide: Document nomodeset kernel parameter

[Daniel Vetter]

On Mon, Nov 08, 2021 at 01:48:24PM +0100, Thomas Zimmermann wrote:
> Hi
> 
> Am 08.11.21 um 13:15 schrieb Javier Martinez Canillas:
> > The nomodeset kernel command line parameter is not documented. Its name
> > is quite vague and is not intuitive what's the behaviour when it is set.
> > 
> > Document in kernel-parameters.txt what actually happens when nomodeset
> > is used. That way, users could know if they want to enable this option.
> > 
> > Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
> > ---
> > 
> > (no changes since v1)
> > 
> >   Documentation/admin-guide/kernel-parameters.txt | 4 ++++
> >   1 file changed, 4 insertions(+)
> > 
> > diff --git Documentation/admin-guide/kernel-parameters.txt Documentation/admin-guide/kernel-parameters.txt
> > index 91ba391f9b32..ed9859fd0734 100644
> > --- Documentation/admin-guide/kernel-parameters.txt
> > +++ Documentation/admin-guide/kernel-parameters.txt
> > @@ -3521,6 +3521,10 @@
> >   			shutdown the other cpus.  Instead use the REBOOT_VECTOR
> >   			irq.
> > +	nomodeset	Disable kernel modesetting. DRM drivers will not be
> > +			loaded when this kernel boot parameter is used. The
> > +			simpledrm driver is the only DRM driver that loads.
> > +
> 
> That's misleading and to the general admin it might not be clear what
> simpledrm is about. Rather say something like
> 
>  Disable kernel modesetting. DRM drivers will not perform
>  display-mode changes or accelerated rendering. Only the
>  system framebuffer will be available for use. Requires the
>  firmware or boot loader to setup the display. Useful as
>  fallback, or for testing and debugging.

Yeah I think that's much clearer. With that wording:

Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>

> 
> Best regards
> Thomas
> 
> >   	nomodule	Disable module load
> >   	nopat		[X86] Disable PAT (page attribute table extension of
> > 
> 
> -- 
> Thomas Zimmermann
> Graphics Driver Developer
> SUSE Software Solutions Germany GmbH
> Maxfeldstr. 5, 90409 Nürnberg, Germany
> (HRB 36809, AG Nürnberg)
> Geschäftsführer: Ivo Totev




-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch

Re: [PATCH v3 5/6] Documentation/admin-guide: Document nomodeset kernel parameter

[Daniel Vetter]

On Mon, Nov 08, 2021 at 01:48:24PM +0100, Thomas Zimmermann wrote:
> Hi
> 
> Am 08.11.21 um 13:15 schrieb Javier Martinez Canillas:
> > The nomodeset kernel command line parameter is not documented. Its name
> > is quite vague and is not intuitive what's the behaviour when it is set.
> > 
> > Document in kernel-parameters.txt what actually happens when nomodeset
> > is used. That way, users could know if they want to enable this option.
> > 
> > Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
> > ---
> > 
> > (no changes since v1)
> > 
> >   Documentation/admin-guide/kernel-parameters.txt | 4 ++++
> >   1 file changed, 4 insertions(+)
> > 
> > diff --git Documentation/admin-guide/kernel-parameters.txt Documentation/admin-guide/kernel-parameters.txt
> > index 91ba391f9b32..ed9859fd0734 100644
> > --- Documentation/admin-guide/kernel-parameters.txt
> > +++ Documentation/admin-guide/kernel-parameters.txt
> > @@ -3521,6 +3521,10 @@
> >   			shutdown the other cpus.  Instead use the REBOOT_VECTOR
> >   			irq.
> > +	nomodeset	Disable kernel modesetting. DRM drivers will not be
> > +			loaded when this kernel boot parameter is used. The
> > +			simpledrm driver is the only DRM driver that loads.
> > +
> 
> That's misleading and to the general admin it might not be clear what
> simpledrm is about. Rather say something like
> 
>  Disable kernel modesetting. DRM drivers will not perform
>  display-mode changes or accelerated rendering. Only the
>  system framebuffer will be available for use. Requires the
>  firmware or boot loader to setup the display. Useful as
>  fallback, or for testing and debugging.

Yeah I think that's much clearer. With that wording:

Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>

> 
> Best regards
> Thomas
> 
> >   	nomodule	Disable module load
> >   	nopat		[X86] Disable PAT (page attribute table extension of
> > 
> 
> -- 
> Thomas Zimmermann
> Graphics Driver Developer
> SUSE Software Solutions Germany GmbH
> Maxfeldstr. 5, 90409 Nürnberg, Germany
> (HRB 36809, AG Nürnberg)
> Geschäftsführer: Ivo Totev




-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch

Re: [PATCH v3 0/6] Cleanups for the nomodeset kernel command line parameter logic

[Jani Nikula]

On Mon, 08 Nov 2021, Javier Martinez Canillas <javierm@redhat.com> wrote:
> Hello Thomas,
>
> On 11/8/21 13:50, Thomas Zimmermann wrote:
>> Hi
>> 
>> Am 08.11.21 um 13:15 schrieb Javier Martinez Canillas:
>>> There is a lot of historical baggage on this parameter. It is defined in
>>> the vgacon driver as nomodeset, but its set function is called text_mode()
>>> and the value queried with a function named vgacon_text_force().
>>>
>>> All this implies that it's about forcing text mode for VGA, yet it is not
>>> used in neither vgacon nor other console driver. The only users for these
>>> are DRM drivers, that check for the vgacon_text_force() return value to
>>> determine whether the driver should be loaded or not.
>>>
>>> That makes it quite confusing to read the code, because the variables and
>>> function names don't reflect what they actually do and also are not in the
>>> same subsystem as the drivers that make use of them.
>>>
>>> This patch-set attempts to cleanup the code by moving the nomodseset param
>>> to the DRM subsystem and do some renaming to make their intention clearer.
>>>
>>> This is a v3 of the patches, that address issues pointed out by Jani Nikula
>>> in v2: https://lkml.org/lkml/2021/11/4/594
>>>
>>> Patch #1 and #2 are just trivial cleanups.
>>>
>>> Patch #3 moves the nomodeset boot option to the DRM subsystem and renames
>>> the variables and functions names.
>>>
>>> Patch #4 removes the relationship between the nomodeset parameter and the
>>> CONFIG_VGA_CONSOLE Kconfig symbol.
>> 
>> On patches 1 to 4
>> 
>> Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
>>
>
> Thanks!
>  
>>>
>>> Patch #5 adds nomodeset to the kernel parameters documentation.
>>>
>>> Patch #6 improves the message when nomodeset is enabled to make it more
>>> accurate and less sensational.
>> 
>> See my comments on these patches.
>>
>
> Yes, agreed with your feedback on these. I'll improve it when posting a v4.

With the changes proposed by Thomas, the series is also

Acked-by: Jani Nikula <jani.nikula@intel.com>

In particular, it's fine to merge the i915 parts via whichever tree
suits you all best (I presume it's drm-misc).

I might have bikeshedded the drm_get_modeset() name and the choice of
drm_mode_config.h to place the declaration... but meh. The series is
definitely an improvement to the status quo.


BR,
Jani.


>
> Best regards, -- 
> Javier Martinez Canillas
> Linux Engineering
> Red Hat
>

-- 
Jani Nikula, Intel Open Source Graphics Center

Re: [PATCH v3 0/6] Cleanups for the nomodeset kernel command line parameter logic

[Jani Nikula]

On Mon, 08 Nov 2021, Javier Martinez Canillas <javierm@redhat.com> wrote:
> Hello Thomas,
>
> On 11/8/21 13:50, Thomas Zimmermann wrote:
>> Hi
>> 
>> Am 08.11.21 um 13:15 schrieb Javier Martinez Canillas:
>>> There is a lot of historical baggage on this parameter. It is defined in
>>> the vgacon driver as nomodeset, but its set function is called text_mode()
>>> and the value queried with a function named vgacon_text_force().
>>>
>>> All this implies that it's about forcing text mode for VGA, yet it is not
>>> used in neither vgacon nor other console driver. The only users for these
>>> are DRM drivers, that check for the vgacon_text_force() return value to
>>> determine whether the driver should be loaded or not.
>>>
>>> That makes it quite confusing to read the code, because the variables and
>>> function names don't reflect what they actually do and also are not in the
>>> same subsystem as the drivers that make use of them.
>>>
>>> This patch-set attempts to cleanup the code by moving the nomodseset param
>>> to the DRM subsystem and do some renaming to make their intention clearer.
>>>
>>> This is a v3 of the patches, that address issues pointed out by Jani Nikula
>>> in v2: https://lkml.org/lkml/2021/11/4/594
>>>
>>> Patch #1 and #2 are just trivial cleanups.
>>>
>>> Patch #3 moves the nomodeset boot option to the DRM subsystem and renames
>>> the variables and functions names.
>>>
>>> Patch #4 removes the relationship between the nomodeset parameter and the
>>> CONFIG_VGA_CONSOLE Kconfig symbol.
>> 
>> On patches 1 to 4
>> 
>> Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
>>
>
> Thanks!
>  
>>>
>>> Patch #5 adds nomodeset to the kernel parameters documentation.
>>>
>>> Patch #6 improves the message when nomodeset is enabled to make it more
>>> accurate and less sensational.
>> 
>> See my comments on these patches.
>>
>
> Yes, agreed with your feedback on these. I'll improve it when posting a v4.

With the changes proposed by Thomas, the series is also

Acked-by: Jani Nikula <jani.nikula@intel.com>

In particular, it's fine to merge the i915 parts via whichever tree
suits you all best (I presume it's drm-misc).

I might have bikeshedded the drm_get_modeset() name and the choice of
drm_mode_config.h to place the declaration... but meh. The series is
definitely an improvement to the status quo.


BR,
Jani.


>
> Best regards, -- 
> Javier Martinez Canillas
> Linux Engineering
> Red Hat
>

-- 
Jani Nikula, Intel Open Source Graphics Center