[PATCH v5 2/9] video/aperture: use generic code to figure out the vga default device

[PATCH v5 2/9] video/aperture: use generic code to figure out the vga default device

[Thomas Zimmermann]

From: Daniel Vetter <daniel.vetter@ffwll.ch>

Since vgaarb has been promoted to be a core piece of the pci subsystem
we don't have to open code random guesses anymore, we actually know
this in a platform agnostic way, and there's no need for an x86
specific hack. See also commit 1d38fe6ee6a8 ("PCI/VGA: Move vgaarb to
drivers/pci")

This should not result in any functional change, and the non-x86
multi-gpu pci systems are probably rare enough to not matter (I don't
know of any tbh). But it's a nice cleanup, so let's do it.

There's been a few questions on previous iterations on dri-devel and
irc:

- fb_is_primary_device() seems to be yet another implementation of
  this theme, and at least on x86 it checks for both
  vga_default_device OR rom shadowing. There shouldn't ever be a case
  where rom shadowing gives any additional hints about the boot vga
  device, but if there is then the default vga selection in vgaarb
  should probably be fixed. And not special-case checks replicated all
  over.

- Thomas also brought up that on most !x86 systems
  fb_is_primary_device() returns 0, except on sparc/parisc. But these
  2 special cases are about platform specific devices and not pci, so
  shouldn't have any interactions.

- Furthermore fb_is_primary_device() is a bit a red herring since it's
  only used to select the right fbdev driver for fbcon, and not for
  the fw handover dance which the aperture helpers handle. At least
  for x86 we might want to look into unifying them, but that's a
  separate thing.

v2: Extend commit message trying to summarize various discussions.

v4:
- make the test for the primary device easier to read (Javier)
- fix commit message style (i.e., commit 1234 ("..."))
- fix Daniel's S-o-b address

v5:
- add back an S-o-b tag with Daniel's Intel address

Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Javier Martinez Canillas <javierm@redhat.com>
Cc: Helge Deller <deller@gmx.de>
Cc: linux-fbdev@vger.kernel.org
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: linux-pci@vger.kernel.org
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
---
 drivers/video/aperture.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/drivers/video/aperture.c b/drivers/video/aperture.c
index 41e77de1ea82..d0eccc4ed60b 100644
--- a/drivers/video/aperture.c
+++ b/drivers/video/aperture.c
@@ -328,9 +328,8 @@ int aperture_remove_conflicting_pci_devices(struct pci_dev *pdev, const char *na
 	resource_size_t base, size;
 	int bar, ret;
 
-#ifdef CONFIG_X86
-	primary = pdev->resource[PCI_ROM_RESOURCE].flags & IORESOURCE_ROM_SHADOW;
-#endif
+	if (pdev == vga_default_device())
+		primary = true;
 
 	for (bar = 0; bar < PCI_STD_NUM_BARS; ++bar) {
 		if (!(pci_resource_flags(pdev, bar) & IORESOURCE_MEM))
-- 
2.40.0

[PATCH v5 3/9] drm/aperture: Remove primary argument

[Thomas Zimmermann]

From: Daniel Vetter <daniel.vetter@ffwll.ch>

Only really pci devices have a business setting this - it's for
figuring out whether the legacy vga stuff should be nuked too. And
with the preceding two patches those are all using the pci version of
this.

Which means for all other callers primary == false and we can remove
it now.

v2:
- Reorder to avoid compile fail (Thomas)
- Include gma500, which retained it's called to the non-pci version.

v4:
- fix Daniel's S-o-b address

v5:
- add back an S-o-b tag with Daniel's Intel address

Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Javier Martinez Canillas <javierm@redhat.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Deepak Rawat <drawat.floss@gmail.com>
Cc: Neil Armstrong <neil.armstrong@linaro.org>
Cc: Kevin Hilman <khilman@baylibre.com>
Cc: Jerome Brunet <jbrunet@baylibre.com>
Cc: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Jonathan Hunter <jonathanh@nvidia.com>
Cc: Emma Anholt <emma@anholt.net>
Cc: Helge Deller <deller@gmx.de>
Cc: David Airlie <airlied@gmail.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: linux-hyperv@vger.kernel.org
Cc: linux-amlogic@lists.infradead.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-tegra@vger.kernel.org
Cc: linux-fbdev@vger.kernel.org
Acked-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
---
 drivers/gpu/drm/arm/hdlcd_drv.c             |  2 +-
 drivers/gpu/drm/armada/armada_drv.c         |  2 +-
 drivers/gpu/drm/drm_aperture.c              | 11 +++--------
 drivers/gpu/drm/gma500/psb_drv.c            |  2 +-
 drivers/gpu/drm/hyperv/hyperv_drm_drv.c     |  1 -
 drivers/gpu/drm/meson/meson_drv.c           |  2 +-
 drivers/gpu/drm/msm/msm_fbdev.c             |  2 +-
 drivers/gpu/drm/rockchip/rockchip_drm_drv.c |  2 +-
 drivers/gpu/drm/stm/drv.c                   |  2 +-
 drivers/gpu/drm/sun4i/sun4i_drv.c           |  2 +-
 drivers/gpu/drm/tegra/drm.c                 |  2 +-
 drivers/gpu/drm/vc4/vc4_drv.c               |  2 +-
 include/drm/drm_aperture.h                  |  7 +++----
 13 files changed, 16 insertions(+), 23 deletions(-)

diff --git a/drivers/gpu/drm/arm/hdlcd_drv.c b/drivers/gpu/drm/arm/hdlcd_drv.c
index 9020bf820bc8..12f5a2c7f03d 100644
--- a/drivers/gpu/drm/arm/hdlcd_drv.c
+++ b/drivers/gpu/drm/arm/hdlcd_drv.c
@@ -285,7 +285,7 @@ static int hdlcd_drm_bind(struct device *dev)
 	 */
 	if (hdlcd_read(hdlcd, HDLCD_REG_COMMAND)) {
 		hdlcd_write(hdlcd, HDLCD_REG_COMMAND, 0);
-		drm_aperture_remove_framebuffers(false, &hdlcd_driver);
+		drm_aperture_remove_framebuffers(&hdlcd_driver);
 	}
 
 	drm_mode_config_reset(drm);
diff --git a/drivers/gpu/drm/armada/armada_drv.c b/drivers/gpu/drm/armada/armada_drv.c
index 0643887800b4..c99ec7078301 100644
--- a/drivers/gpu/drm/armada/armada_drv.c
+++ b/drivers/gpu/drm/armada/armada_drv.c
@@ -95,7 +95,7 @@ static int armada_drm_bind(struct device *dev)
 	}
 
 	/* Remove early framebuffers */
-	ret = drm_aperture_remove_framebuffers(false, &armada_drm_driver);
+	ret = drm_aperture_remove_framebuffers(&armada_drm_driver);
 	if (ret) {
 		dev_err(dev, "[" DRM_NAME ":%s] can't kick out simple-fb: %d\n",
 			__func__, ret);
diff --git a/drivers/gpu/drm/drm_aperture.c b/drivers/gpu/drm/drm_aperture.c
index 3b8fdeeafd53..697cffbfd603 100644
--- a/drivers/gpu/drm/drm_aperture.c
+++ b/drivers/gpu/drm/drm_aperture.c
@@ -32,17 +32,13 @@
  *
  *	static int remove_conflicting_framebuffers(struct pci_dev *pdev)
  *	{
- *		bool primary = false;
  *		resource_size_t base, size;
  *		int ret;
  *
  *		base = pci_resource_start(pdev, 0);
  *		size = pci_resource_len(pdev, 0);
- *	#ifdef CONFIG_X86
- *		primary = pdev->resource[PCI_ROM_RESOURCE].flags & IORESOURCE_ROM_SHADOW;
- *	#endif
  *
- *		return drm_aperture_remove_conflicting_framebuffers(base, size, primary,
+ *		return drm_aperture_remove_conflicting_framebuffers(base, size,
  *		                                                    &example_driver);
  *	}
  *
@@ -161,7 +157,6 @@ EXPORT_SYMBOL(devm_aperture_acquire_from_firmware);
  * drm_aperture_remove_conflicting_framebuffers - remove existing framebuffers in the given range
  * @base: the aperture's base address in physical memory
  * @size: aperture size in bytes
- * @primary: also kick vga16fb if present
  * @req_driver: requesting DRM driver
  *
  * This function removes graphics device drivers which use the memory range described by
@@ -171,9 +166,9 @@ EXPORT_SYMBOL(devm_aperture_acquire_from_firmware);
  * 0 on success, or a negative errno code otherwise
  */
 int drm_aperture_remove_conflicting_framebuffers(resource_size_t base, resource_size_t size,
-						 bool primary, const struct drm_driver *req_driver)
+						 const struct drm_driver *req_driver)
 {
-	return aperture_remove_conflicting_devices(base, size, primary, req_driver->name);
+	return aperture_remove_conflicting_devices(base, size, false, req_driver->name);
 }
 EXPORT_SYMBOL(drm_aperture_remove_conflicting_framebuffers);
 
diff --git a/drivers/gpu/drm/gma500/psb_drv.c b/drivers/gpu/drm/gma500/psb_drv.c
index f1e0eed8fea4..4bb06a89e48d 100644
--- a/drivers/gpu/drm/gma500/psb_drv.c
+++ b/drivers/gpu/drm/gma500/psb_drv.c
@@ -428,7 +428,7 @@ static int psb_pci_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 	 * TODO: Refactor psb_driver_load() to map vdc_reg earlier. Then we
 	 *       might be able to read the framebuffer range from the device.
 	 */
-	ret = drm_aperture_remove_framebuffers(false, &driver);
+	ret = drm_aperture_remove_framebuffers(&driver);
 	if (ret)
 		return ret;
 
diff --git a/drivers/gpu/drm/hyperv/hyperv_drm_drv.c b/drivers/gpu/drm/hyperv/hyperv_drm_drv.c
index f830d62a5ce6..a7d2c92d6c6a 100644
--- a/drivers/gpu/drm/hyperv/hyperv_drm_drv.c
+++ b/drivers/gpu/drm/hyperv/hyperv_drm_drv.c
@@ -74,7 +74,6 @@ static int hyperv_setup_vram(struct hyperv_drm_device *hv,
 
 	drm_aperture_remove_conflicting_framebuffers(screen_info.lfb_base,
 						     screen_info.lfb_size,
-						     false,
 						     &hyperv_driver);
 
 	hv->fb_size = (unsigned long)hv->mmio_megabytes * 1024 * 1024;
diff --git a/drivers/gpu/drm/meson/meson_drv.c b/drivers/gpu/drm/meson/meson_drv.c
index bb72fda9106d..ca6d1e59e5d9 100644
--- a/drivers/gpu/drm/meson/meson_drv.c
+++ b/drivers/gpu/drm/meson/meson_drv.c
@@ -285,7 +285,7 @@ static int meson_drv_bind_master(struct device *dev, bool has_components)
 	 * Remove early framebuffers (ie. simplefb). The framebuffer can be
 	 * located anywhere in RAM
 	 */
-	ret = drm_aperture_remove_framebuffers(false, &meson_driver);
+	ret = drm_aperture_remove_framebuffers(&meson_driver);
 	if (ret)
 		goto free_drm;
 
diff --git a/drivers/gpu/drm/msm/msm_fbdev.c b/drivers/gpu/drm/msm/msm_fbdev.c
index d26aa52217ce..16652a5a7018 100644
--- a/drivers/gpu/drm/msm/msm_fbdev.c
+++ b/drivers/gpu/drm/msm/msm_fbdev.c
@@ -155,7 +155,7 @@ struct drm_fb_helper *msm_fbdev_init(struct drm_device *dev)
 	}
 
 	/* the fw fb could be anywhere in memory */
-	ret = drm_aperture_remove_framebuffers(false, dev->driver);
+	ret = drm_aperture_remove_framebuffers(dev->driver);
 	if (ret)
 		goto fini;
 
diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_drv.c b/drivers/gpu/drm/rockchip/rockchip_drm_drv.c
index 6e0788d14c10..d97f2edc646b 100644
--- a/drivers/gpu/drm/rockchip/rockchip_drm_drv.c
+++ b/drivers/gpu/drm/rockchip/rockchip_drm_drv.c
@@ -140,7 +140,7 @@ static int rockchip_drm_bind(struct device *dev)
 	int ret;
 
 	/* Remove existing drivers that may own the framebuffer memory. */
-	ret = drm_aperture_remove_framebuffers(false, &rockchip_drm_driver);
+	ret = drm_aperture_remove_framebuffers(&rockchip_drm_driver);
 	if (ret) {
 		DRM_DEV_ERROR(dev,
 			      "Failed to remove existing framebuffers - %d.\n",
diff --git a/drivers/gpu/drm/stm/drv.c b/drivers/gpu/drm/stm/drv.c
index 422220df7d8c..cb4404b3ce62 100644
--- a/drivers/gpu/drm/stm/drv.c
+++ b/drivers/gpu/drm/stm/drv.c
@@ -185,7 +185,7 @@ static int stm_drm_platform_probe(struct platform_device *pdev)
 
 	DRM_DEBUG("%s\n", __func__);
 
-	ret = drm_aperture_remove_framebuffers(false, &drv_driver);
+	ret = drm_aperture_remove_framebuffers(&drv_driver);
 	if (ret)
 		return ret;
 
diff --git a/drivers/gpu/drm/sun4i/sun4i_drv.c b/drivers/gpu/drm/sun4i/sun4i_drv.c
index e49f78a6a8cf..daa7faf72a4b 100644
--- a/drivers/gpu/drm/sun4i/sun4i_drv.c
+++ b/drivers/gpu/drm/sun4i/sun4i_drv.c
@@ -98,7 +98,7 @@ static int sun4i_drv_bind(struct device *dev)
 		goto unbind_all;
 
 	/* Remove early framebuffers (ie. simplefb) */
-	ret = drm_aperture_remove_framebuffers(false, &sun4i_drv_driver);
+	ret = drm_aperture_remove_framebuffers(&sun4i_drv_driver);
 	if (ret)
 		goto unbind_all;
 
diff --git a/drivers/gpu/drm/tegra/drm.c b/drivers/gpu/drm/tegra/drm.c
index 6ca9f396e55b..d11d259f9399 100644
--- a/drivers/gpu/drm/tegra/drm.c
+++ b/drivers/gpu/drm/tegra/drm.c
@@ -1252,7 +1252,7 @@ static int host1x_drm_probe(struct host1x_device *dev)
 
 	drm_mode_config_reset(drm);
 
-	err = drm_aperture_remove_framebuffers(false, &tegra_drm_driver);
+	err = drm_aperture_remove_framebuffers(&tegra_drm_driver);
 	if (err < 0)
 		goto hub;
 
diff --git a/drivers/gpu/drm/vc4/vc4_drv.c b/drivers/gpu/drm/vc4/vc4_drv.c
index c8bf954042e0..823395c23cc3 100644
--- a/drivers/gpu/drm/vc4/vc4_drv.c
+++ b/drivers/gpu/drm/vc4/vc4_drv.c
@@ -350,7 +350,7 @@ static int vc4_drm_bind(struct device *dev)
 			return -EPROBE_DEFER;
 	}
 
-	ret = drm_aperture_remove_framebuffers(false, driver);
+	ret = drm_aperture_remove_framebuffers(driver);
 	if (ret)
 		return ret;
 
diff --git a/include/drm/drm_aperture.h b/include/drm/drm_aperture.h
index 7096703c3949..cbe33b49fd5d 100644
--- a/include/drm/drm_aperture.h
+++ b/include/drm/drm_aperture.h
@@ -13,14 +13,13 @@ int devm_aperture_acquire_from_firmware(struct drm_device *dev, resource_size_t
 					resource_size_t size);
 
 int drm_aperture_remove_conflicting_framebuffers(resource_size_t base, resource_size_t size,
-						 bool primary, const struct drm_driver *req_driver);
+						 const struct drm_driver *req_driver);
 
 int drm_aperture_remove_conflicting_pci_framebuffers(struct pci_dev *pdev,
 						     const struct drm_driver *req_driver);
 
 /**
  * drm_aperture_remove_framebuffers - remove all existing framebuffers
- * @primary: also kick vga16fb if present
  * @req_driver: requesting DRM driver
  *
  * This function removes all graphics device drivers. Use this function on systems
@@ -30,9 +29,9 @@ int drm_aperture_remove_conflicting_pci_framebuffers(struct pci_dev *pdev,
  * 0 on success, or a negative errno code otherwise
  */
 static inline int
-drm_aperture_remove_framebuffers(bool primary, const struct drm_driver *req_driver)
+drm_aperture_remove_framebuffers(const struct drm_driver *req_driver)
 {
-	return drm_aperture_remove_conflicting_framebuffers(0, (resource_size_t)-1, primary,
+	return drm_aperture_remove_conflicting_framebuffers(0, (resource_size_t)-1,
 							    req_driver);
 }
 
-- 
2.40.0

[PATCH v5 4/9] video/aperture: Only kick vgacon when the pdev is decoding vga

[Thomas Zimmermann]

From: Daniel Vetter <daniel.vetter@ffwll.ch>

Otherwise it's a bit silly, and we might throw out the driver for the
screen the user is actually looking at. I haven't found a bug report
for this case yet, but we did get bug reports for the analog case
where we're throwing out the efifb driver.

v2: Flip the check around to make it clear it's a special case for
kicking out the vgacon driver only (Thomas)

v4:
- fixes to commit message
- fix Daniel's S-o-b address

v5:
- add back an S-o-b tag with Daniel's Intel address

Link: https://bugzilla.kernel.org/show_bug.cgi?id=216303
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Javier Martinez Canillas <javierm@redhat.com>
Cc: Helge Deller <deller@gmx.de>
Cc: linux-fbdev@vger.kernel.org
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
---
 drivers/video/aperture.c | 16 +++++++++-------
 1 file changed, 9 insertions(+), 7 deletions(-)

diff --git a/drivers/video/aperture.c b/drivers/video/aperture.c
index d0eccc4ed60b..26bdba6b2725 100644
--- a/drivers/video/aperture.c
+++ b/drivers/video/aperture.c
@@ -342,13 +342,15 @@ int aperture_remove_conflicting_pci_devices(struct pci_dev *pdev, const char *na
 			return ret;
 	}
 
-	/*
-	 * WARNING: Apparently we must kick fbdev drivers before vgacon,
-	 * otherwise the vga fbdev driver falls over.
-	 */
-	ret = vga_remove_vgacon(pdev);
-	if (ret)
-		return ret;
+	if (primary) {
+		/*
+		 * WARNING: Apparently we must kick fbdev drivers before vgacon,
+		 * otherwise the vga fbdev driver falls over.
+		 */
+		ret = vga_remove_vgacon(pdev);
+		if (ret)
+			return ret;
+	}
 
 	return 0;
 
-- 
2.40.0

[PATCH v5 5/9] video/aperture: Move vga handling to pci function

[Thomas Zimmermann]

From: Daniel Vetter <daniel.vetter@ffwll.ch>

A few reasons for this:

- It's really the only one where this matters. I tried looking around,
  and I didn't find any non-pci vga-compatible controllers for x86
  (since that's the only platform where we had this until a few
  patches ago), where a driver participating in the aperture claim
  dance would interfere.

- I also don't expect that any future bus anytime soon will
  not just look like pci towards the OS, that's been the case for like
  25+ years by now for practically everything (even non non-x86).

- Also it's a bit funny if we have one part of the vga removal in the
  pci function, and the other in the generic one.

v2: Rebase.

v4:
- fix Daniel's S-o-b address

v5:
- add back an S-o-b tag with Daniel's Intel address

Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Javier Martinez Canillas <javierm@redhat.com>
Cc: Helge Deller <deller@gmx.de>
Cc: linux-fbdev@vger.kernel.org
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
---
 drivers/video/aperture.c | 15 +++++++--------
 1 file changed, 7 insertions(+), 8 deletions(-)

diff --git a/drivers/video/aperture.c b/drivers/video/aperture.c
index 26bdba6b2725..3aad10ab620e 100644
--- a/drivers/video/aperture.c
+++ b/drivers/video/aperture.c
@@ -298,14 +298,6 @@ int aperture_remove_conflicting_devices(resource_size_t base, resource_size_t si
 
 	aperture_detach_devices(base, size);
 
-	/*
-	 * If this is the primary adapter, there could be a VGA device
-	 * that consumes the VGA framebuffer I/O range. Remove this device
-	 * as well.
-	 */
-	if (primary)
-		aperture_detach_devices(VGA_FB_PHYS_BASE, VGA_FB_PHYS_SIZE);
-
 	return 0;
 }
 EXPORT_SYMBOL(aperture_remove_conflicting_devices);
@@ -343,6 +335,13 @@ int aperture_remove_conflicting_pci_devices(struct pci_dev *pdev, const char *na
 	}
 
 	if (primary) {
+		/*
+		 * If this is the primary adapter, there could be a VGA device
+		 * that consumes the VGA framebuffer I/O range. Remove this
+		 * device as well.
+		 */
+		aperture_detach_devices(VGA_FB_PHYS_BASE, VGA_FB_PHYS_SIZE);
+
 		/*
 		 * WARNING: Apparently we must kick fbdev drivers before vgacon,
 		 * otherwise the vga fbdev driver falls over.
-- 
2.40.0

[PATCH v5 6/9] video/aperture: Drop primary argument

[Thomas Zimmermann]

From: Daniel Vetter <daniel.vetter@ffwll.ch>

With the preceding patches it's become defunct. Also I'm about to add
a different boolean argument, so it's better to keep the confusion
down to the absolute minimum.

v2: Since the hypervfb patch got droppped (it's only a pci device for
gen1 vm, not for gen2) there is one leftover user in an actual driver
left to touch.

v4:
- fixes to commit message
- fix Daniel's S-o-b address

v5:
- add back an S-o-b tag with Daniel's Intel address

Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Javier Martinez Canillas <javierm@redhat.com>
Cc: Helge Deller <deller@gmx.de>
Cc: linux-fbdev@vger.kernel.org
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Wei Liu <wei.liu@kernel.org>
Cc: Dexuan Cui <decui@microsoft.com>
Cc: linux-hyperv@vger.kernel.org
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
---
 drivers/gpu/drm/drm_aperture.c  | 2 +-
 drivers/video/aperture.c        | 7 +++----
 drivers/video/fbdev/hyperv_fb.c | 2 +-
 include/linux/aperture.h        | 9 ++++-----
 4 files changed, 9 insertions(+), 11 deletions(-)

diff --git a/drivers/gpu/drm/drm_aperture.c b/drivers/gpu/drm/drm_aperture.c
index 697cffbfd603..5729f3bb4398 100644
--- a/drivers/gpu/drm/drm_aperture.c
+++ b/drivers/gpu/drm/drm_aperture.c
@@ -168,7 +168,7 @@ EXPORT_SYMBOL(devm_aperture_acquire_from_firmware);
 int drm_aperture_remove_conflicting_framebuffers(resource_size_t base, resource_size_t size,
 						 const struct drm_driver *req_driver)
 {
-	return aperture_remove_conflicting_devices(base, size, false, req_driver->name);
+	return aperture_remove_conflicting_devices(base, size, req_driver->name);
 }
 EXPORT_SYMBOL(drm_aperture_remove_conflicting_framebuffers);
 
diff --git a/drivers/video/aperture.c b/drivers/video/aperture.c
index 3aad10ab620e..1356f0e88241 100644
--- a/drivers/video/aperture.c
+++ b/drivers/video/aperture.c
@@ -43,7 +43,7 @@
  *		base = mem->start;
  *		size = resource_size(mem);
  *
- *		ret = aperture_remove_conflicting_devices(base, size, false, "example");
+ *		ret = aperture_remove_conflicting_devices(base, size, "example");
  *		if (ret)
  *			return ret;
  *
@@ -274,7 +274,6 @@ static void aperture_detach_devices(resource_size_t base, resource_size_t size)
  * aperture_remove_conflicting_devices - remove devices in the given range
  * @base: the aperture's base address in physical memory
  * @size: aperture size in bytes
- * @primary: also kick vga16fb if present; only relevant for VGA devices
  * @name: a descriptive name of the requesting driver
  *
  * This function removes devices that own apertures within @base and @size.
@@ -283,7 +282,7 @@ static void aperture_detach_devices(resource_size_t base, resource_size_t size)
  * 0 on success, or a negative errno code otherwise
  */
 int aperture_remove_conflicting_devices(resource_size_t base, resource_size_t size,
-					bool primary, const char *name)
+					const char *name)
 {
 	/*
 	 * If a driver asked to unregister a platform device registered by
@@ -329,7 +328,7 @@ int aperture_remove_conflicting_pci_devices(struct pci_dev *pdev, const char *na
 
 		base = pci_resource_start(pdev, bar);
 		size = pci_resource_len(pdev, bar);
-		ret = aperture_remove_conflicting_devices(base, size, primary, name);
+		ret = aperture_remove_conflicting_devices(base, size, name);
 		if (ret)
 			return ret;
 	}
diff --git a/drivers/video/fbdev/hyperv_fb.c b/drivers/video/fbdev/hyperv_fb.c
index ec3f6cf05f8c..54f433e09ab8 100644
--- a/drivers/video/fbdev/hyperv_fb.c
+++ b/drivers/video/fbdev/hyperv_fb.c
@@ -1073,7 +1073,7 @@ static int hvfb_getmem(struct hv_device *hdev, struct fb_info *info)
 	info->screen_size = dio_fb_size;
 
 getmem_done:
-	aperture_remove_conflicting_devices(base, size, false, KBUILD_MODNAME);
+	aperture_remove_conflicting_devices(base, size, KBUILD_MODNAME);
 
 	if (gen2vm) {
 		/* framebuffer is reallocated, clear screen_info to avoid misuse from kexec */
diff --git a/include/linux/aperture.h b/include/linux/aperture.h
index 442f15a57cad..7248727753be 100644
--- a/include/linux/aperture.h
+++ b/include/linux/aperture.h
@@ -14,7 +14,7 @@ int devm_aperture_acquire_for_platform_device(struct platform_device *pdev,
 					      resource_size_t size);
 
 int aperture_remove_conflicting_devices(resource_size_t base, resource_size_t size,
-					bool primary, const char *name);
+					const char *name);
 
 int aperture_remove_conflicting_pci_devices(struct pci_dev *pdev, const char *name);
 #else
@@ -26,7 +26,7 @@ static inline int devm_aperture_acquire_for_platform_device(struct platform_devi
 }
 
 static inline int aperture_remove_conflicting_devices(resource_size_t base, resource_size_t size,
-						      bool primary, const char *name)
+						      const char *name)
 {
 	return 0;
 }
@@ -39,7 +39,6 @@ static inline int aperture_remove_conflicting_pci_devices(struct pci_dev *pdev,
 
 /**
  * aperture_remove_all_conflicting_devices - remove all existing framebuffers
- * @primary: also kick vga16fb if present; only relevant for VGA devices
  * @name: a descriptive name of the requesting driver
  *
  * This function removes all graphics device drivers. Use this function on systems
@@ -48,9 +47,9 @@ static inline int aperture_remove_conflicting_pci_devices(struct pci_dev *pdev,
  * Returns:
  * 0 on success, or a negative errno code otherwise
  */
-static inline int aperture_remove_all_conflicting_devices(bool primary, const char *name)
+static inline int aperture_remove_all_conflicting_devices(const char *name)
 {
-	return aperture_remove_conflicting_devices(0, (resource_size_t)-1, primary, name);
+	return aperture_remove_conflicting_devices(0, (resource_size_t)-1, name);
 }
 
 #endif
-- 
2.40.0

Re: [PATCH v5 2/9] video/aperture: use generic code to figure out the vga default device

[Helge Deller]

On 4/6/23 15:21, Thomas Zimmermann wrote:
> From: Daniel Vetter <daniel.vetter@ffwll.ch>
>
> Since vgaarb has been promoted to be a core piece of the pci subsystem
> we don't have to open code random guesses anymore, we actually know
> this in a platform agnostic way, and there's no need for an x86
> specific hack. See also commit 1d38fe6ee6a8 ("PCI/VGA: Move vgaarb to
> drivers/pci")
>
> This should not result in any functional change, and the non-x86
> multi-gpu pci systems are probably rare enough to not matter (I don't
> know of any tbh). But it's a nice cleanup, so let's do it.
>
> There's been a few questions on previous iterations on dri-devel and
> irc:
>
> - fb_is_primary_device() seems to be yet another implementation of
>    this theme, and at least on x86 it checks for both
>    vga_default_device OR rom shadowing. There shouldn't ever be a case
>    where rom shadowing gives any additional hints about the boot vga
>    device, but if there is then the default vga selection in vgaarb
>    should probably be fixed. And not special-case checks replicated all
>    over.
>
> - Thomas also brought up that on most !x86 systems
>    fb_is_primary_device() returns 0, except on sparc/parisc. But these
>    2 special cases are about platform specific devices and not pci, so
>    shouldn't have any interactions.

Nearly all graphics cards on parisc machines are actually PCI cards,
but the way we handle the handover to graphics mode with STIcore doesn't
conflicts with your planned aperture changes.
So no problem as far as I can see for parisc...

Helge

Re: [PATCH v5 2/9] video/aperture: use generic code to figure out the vga default device

[Daniel Vetter]

On Fri, Apr 07, 2023 at 10:54:00PM +0200, Helge Deller wrote:
> On 4/6/23 15:21, Thomas Zimmermann wrote:
> > From: Daniel Vetter <daniel.vetter@ffwll.ch>
> > 
> > Since vgaarb has been promoted to be a core piece of the pci subsystem
> > we don't have to open code random guesses anymore, we actually know
> > this in a platform agnostic way, and there's no need for an x86
> > specific hack. See also commit 1d38fe6ee6a8 ("PCI/VGA: Move vgaarb to
> > drivers/pci")
> > 
> > This should not result in any functional change, and the non-x86
> > multi-gpu pci systems are probably rare enough to not matter (I don't
> > know of any tbh). But it's a nice cleanup, so let's do it.
> > 
> > There's been a few questions on previous iterations on dri-devel and
> > irc:
> > 
> > - fb_is_primary_device() seems to be yet another implementation of
> >    this theme, and at least on x86 it checks for both
> >    vga_default_device OR rom shadowing. There shouldn't ever be a case
> >    where rom shadowing gives any additional hints about the boot vga
> >    device, but if there is then the default vga selection in vgaarb
> >    should probably be fixed. And not special-case checks replicated all
> >    over.
> > 
> > - Thomas also brought up that on most !x86 systems
> >    fb_is_primary_device() returns 0, except on sparc/parisc. But these
> >    2 special cases are about platform specific devices and not pci, so
> >    shouldn't have any interactions.
> 
> Nearly all graphics cards on parisc machines are actually PCI cards,
> but the way we handle the handover to graphics mode with STIcore doesn't
> conflicts with your planned aperture changes.
> So no problem as far as I can see for parisc...

Ah I thought sticore was some very special bus, if those can be pci cards
underneath then I guess some cleanup eventually might be a good idea? For
anything with a pci bus it's rather strange when vgaarb and
fb_is_primary_device() aren't a match ...
-Daniel
-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch

Re: [PATCH v5 2/9] video/aperture: use generic code to figure out the vga default device

[Helge Deller]

On 4/11/23 16:36, Daniel Vetter wrote:
> On Fri, Apr 07, 2023 at 10:54:00PM +0200, Helge Deller wrote:
>> On 4/6/23 15:21, Thomas Zimmermann wrote:
>>> From: Daniel Vetter <daniel.vetter@ffwll.ch>
>>>
>>> Since vgaarb has been promoted to be a core piece of the pci subsystem
>>> we don't have to open code random guesses anymore, we actually know
>>> this in a platform agnostic way, and there's no need for an x86
>>> specific hack. See also commit 1d38fe6ee6a8 ("PCI/VGA: Move vgaarb to
>>> drivers/pci")
>>>
>>> This should not result in any functional change, and the non-x86
>>> multi-gpu pci systems are probably rare enough to not matter (I don't
>>> know of any tbh). But it's a nice cleanup, so let's do it.
>>>
>>> There's been a few questions on previous iterations on dri-devel and
>>> irc:
>>>
>>> - fb_is_primary_device() seems to be yet another implementation of
>>>     this theme, and at least on x86 it checks for both
>>>     vga_default_device OR rom shadowing. There shouldn't ever be a case
>>>     where rom shadowing gives any additional hints about the boot vga
>>>     device, but if there is then the default vga selection in vgaarb
>>>     should probably be fixed. And not special-case checks replicated all
>>>     over.
>>>
>>> - Thomas also brought up that on most !x86 systems
>>>     fb_is_primary_device() returns 0, except on sparc/parisc. But these
>>>     2 special cases are about platform specific devices and not pci, so
>>>     shouldn't have any interactions.
>>
>> Nearly all graphics cards on parisc machines are actually PCI cards,
>> but the way we handle the handover to graphics mode with STIcore doesn't
>> conflicts with your planned aperture changes.
>> So no problem as far as I can see for parisc...
>
> Ah I thought sticore was some very special bus, if those can be pci cards

STI stands for "Standard Text Interface" [1], which is a API of ROM functions
to output text chars on a console. It's comparable to the text output functions
in a PC-BIOS on x86 and dependend on the ROM it drives any supported card which has
a parisc ROM. So, STI supports cards on PCI & AGP busses, as well on older GSC busses.
[1] https://parisc.wiki.kernel.org/images-parisc/e/e3/Sti.pdf

> underneath then I guess some cleanup eventually might be a good idea? For
> anything with a pci bus it's rather strange when vgaarb and
> fb_is_primary_device() aren't a match ...

There is no VGA on parisc, so there is no conflict. Cards come either with
a parisc STI ROM to support text mode, or they will only be used as secondary
cards only.  The graphics mode is only done in userspace by specific drivers, e.g.
by the X11 server in HP-UX.
Even on x86 the BIOS will only show text output if the graphics card comes
with a VGA-compatible BIOS.

Helge

Re: [PATCH v5 2/9] video/aperture: use generic code to figure out the vga default device

[Daniel Vetter]

On Tue, Apr 11, 2023 at 05:25:47PM +0200, Helge Deller wrote:
> On 4/11/23 16:36, Daniel Vetter wrote:
> > On Fri, Apr 07, 2023 at 10:54:00PM +0200, Helge Deller wrote:
> > > On 4/6/23 15:21, Thomas Zimmermann wrote:
> > > > From: Daniel Vetter <daniel.vetter@ffwll.ch>
> > > > 
> > > > Since vgaarb has been promoted to be a core piece of the pci subsystem
> > > > we don't have to open code random guesses anymore, we actually know
> > > > this in a platform agnostic way, and there's no need for an x86
> > > > specific hack. See also commit 1d38fe6ee6a8 ("PCI/VGA: Move vgaarb to
> > > > drivers/pci")
> > > > 
> > > > This should not result in any functional change, and the non-x86
> > > > multi-gpu pci systems are probably rare enough to not matter (I don't
> > > > know of any tbh). But it's a nice cleanup, so let's do it.
> > > > 
> > > > There's been a few questions on previous iterations on dri-devel and
> > > > irc:
> > > > 
> > > > - fb_is_primary_device() seems to be yet another implementation of
> > > >     this theme, and at least on x86 it checks for both
> > > >     vga_default_device OR rom shadowing. There shouldn't ever be a case
> > > >     where rom shadowing gives any additional hints about the boot vga
> > > >     device, but if there is then the default vga selection in vgaarb
> > > >     should probably be fixed. And not special-case checks replicated all
> > > >     over.
> > > > 
> > > > - Thomas also brought up that on most !x86 systems
> > > >     fb_is_primary_device() returns 0, except on sparc/parisc. But these
> > > >     2 special cases are about platform specific devices and not pci, so
> > > >     shouldn't have any interactions.
> > > 
> > > Nearly all graphics cards on parisc machines are actually PCI cards,
> > > but the way we handle the handover to graphics mode with STIcore doesn't
> > > conflicts with your planned aperture changes.
> > > So no problem as far as I can see for parisc...
> > 
> > Ah I thought sticore was some very special bus, if those can be pci cards
> 
> STI stands for "Standard Text Interface" [1], which is a API of ROM functions
> to output text chars on a console. It's comparable to the text output functions
> in a PC-BIOS on x86 and dependend on the ROM it drives any supported card which has
> a parisc ROM. So, STI supports cards on PCI & AGP busses, as well on older GSC busses.
> [1] https://parisc.wiki.kernel.org/images-parisc/e/e3/Sti.pdf
> 
> > underneath then I guess some cleanup eventually might be a good idea? For
> > anything with a pci bus it's rather strange when vgaarb and
> > fb_is_primary_device() aren't a match ...
> 
> There is no VGA on parisc, so there is no conflict. Cards come either with
> a parisc STI ROM to support text mode, or they will only be used as secondary
> cards only.  The graphics mode is only done in userspace by specific drivers, e.g.
> by the X11 server in HP-UX.
> Even on x86 the BIOS will only show text output if the graphics card comes
> with a VGA-compatible BIOS.

tbf after reading vt.c and fbcon.c some more I'm pretty sure my patch is
nonsense. As sure as you can be with vt/fbcon :-/

Since it sounds like it's a driver bug, maybe a patch to do a pr_warn in
register_framebuffer if there's no mode? I read a pile of code around
modedb.c right now, and there's a lot of things that silently assume that
you always have a mode. So would be good thing to check.
-Daniel
-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch