HiAttached is the patch to provide gma500 with an interface to remove the VGA devices. Hopefully this, otherwise, I'd respin the whole series.
Best regards Thomas Am 04.04.23 um 22:18 schrieb Daniel Vetter:
This one nukes all framebuffers, which is a bit much. In reality gma500 is igpu and never shipped with anything discrete, so there should not be any difference. v2: Unfortunately the framebuffer sits outside of the pci bars for gma500, and so only using the pci helpers won't be enough. Otoh if we only use non-pci helper, then we don't get the vga handling, and subsequent refactoring to untangle these special cases won't work. It's not pretty, but the simplest fix (since gma500 really is the only quirky pci driver like this we have) is to just have both calls. Signed-off-by: Daniel Vetter <daniel.vetter@xxxxxxxxx> Cc: Patrik Jakobsson <patrik.r.jakobsson@xxxxxxxxx> Cc: Thomas Zimmermann <tzimmermann@xxxxxxx> Cc: Javier Martinez Canillas <javierm@xxxxxxxxxx> --- drivers/gpu/drm/gma500/psb_drv.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/gma500/psb_drv.c b/drivers/gpu/drm/gma500/psb_drv.c index 2ce96b1b9c74..f1e0eed8fea4 100644 --- a/drivers/gpu/drm/gma500/psb_drv.c +++ b/drivers/gpu/drm/gma500/psb_drv.c @@ -422,12 +422,17 @@ static int psb_pci_probe(struct pci_dev *pdev, const struct pci_device_id *ent)/** We cannot yet easily find the framebuffer's location in memory. So - * remove all framebuffers here. + * remove all framebuffers here. Note that we still want the pci special + * handling to kick out vgacon. * * 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(true, &driver); + ret = drm_aperture_remove_framebuffers(false, &driver); + if (ret) + return ret; + + ret = drm_aperture_remove_conflicting_pci_framebuffers(pdev, &driver); if (ret) return ret;
-- Thomas Zimmermann Graphics Driver Developer SUSE Software Solutions Germany GmbH Maxfeldstr. 5, 90409 Nürnberg, Germany (HRB 36809, AG Nürnberg) Geschäftsführer: Ivo Totev
From 1a6c6730f93567444a6bfecf1b9bae22563a5c9d Mon Sep 17 00:00:00 2001 From: Thomas Zimmermann <tzimmermann@xxxxxxx> Date: Wed, 5 Apr 2023 21:04:34 +0200 Subject: video/aperture: Provide a VGA helper for gma500 and internal use The hardware for gma500 is different from the rest, as it uses stolen framebuffer memory that is not available via PCI BAR. The regular PCI removal helper cannot detect the framebuffer, while the non-PCI helper misses possible conflicting VGA devices (i.e., a framebuffer or text console). Gma500 therefore calls both helpers to catch all cases. It's confusing as it implies that there's something about the PCI device that requires ownership management. The relationship between the PCI device and the VGA devices is non-obvious. At worst, readers might assume that calling two functions for aperture clearing ownership is a bug in the driver. Hence, move the PCI removal helper's code for VGA functionality into a separate function and call this function from gma500. Documents the purpose of each call to aperture helpers. The change contains comments and example code form the discussion at [1]. Signed-off-by: Thomas Zimmermann <tzimmermann@xxxxxxx> Link: https://patchwork.kernel.org/project/dri-devel/patch/20230404201842.567344-1-daniel.vetter@xxxxxxxx/ # 1 --- drivers/gpu/drm/gma500/psb_drv.c | 48 ++++++++++++++++++-------- drivers/video/aperture.c | 58 ++++++++++++++++++++++---------- include/linux/aperture.h | 7 ++++ 3 files changed, 81 insertions(+), 32 deletions(-) diff --git a/drivers/gpu/drm/gma500/psb_drv.c b/drivers/gpu/drm/gma500/psb_drv.c index 4bb06a89e48d..51fd34bb84f3 100644 --- a/drivers/gpu/drm/gma500/psb_drv.c +++ b/drivers/gpu/drm/gma500/psb_drv.c @@ -7,6 +7,7 @@ * **************************************************************************/ +#include <linux/aperture.h> #include <linux/cpu.h> #include <linux/module.h> #include <linux/notifier.h> @@ -19,7 +20,6 @@ #include <acpi/video.h> #include <drm/drm.h> -#include <drm/drm_aperture.h> #include <drm/drm_drv.h> #include <drm/drm_file.h> #include <drm/drm_ioctl.h> @@ -414,25 +414,45 @@ static int psb_driver_load(struct drm_device *dev, unsigned long flags) return ret; } -static int psb_pci_probe(struct pci_dev *pdev, const struct pci_device_id *ent) +/* + * Hardware for gma500 is a hybrid device, which both acts as a PCI + * device (for legacy vga functionality) but also more like an + * integrated display on a SoC where the framebuffer simply + * resides in main memory and not in a special PCI bar (that + * internally redirects to a stolen range of main memory) like all + * other integrated PCI display devices have. + * + * To catch all cases we need to remove conflicting firmware devices + * for the stolen system memory and for the VGA functionality. As we + * currently cannot easily find the framebuffer's location in stolen + * memory, we remove all framebuffers here. + * + * TODO: Refactor psb_driver_load() to map vdc_reg earlier. Then + * we might be able to read the framebuffer range from the + * device. + */ +static int gma_remove_conflicting_framebuffers(struct pci_dev *pdev, + const struct drm_driver *req_driver) { - struct drm_psb_private *dev_priv; - struct drm_device *dev; + resource_size_t base = 0; + resource_size_t size = PHYS_ADDR_MAX; + const char *name = req_driver->name; int ret; - /* - * We cannot yet easily find the framebuffer's location in memory. So - * remove all framebuffers here. Note that we still want the pci special - * handling to kick out vgacon. - * - * 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(&driver); + ret = aperture_remove_conflicting_devices(base, size, name); if (ret) return ret; - ret = drm_aperture_remove_conflicting_pci_framebuffers(pdev, &driver); + return __aperture_remove_legacy_vga_devices(pdev); +} + +static int psb_pci_probe(struct pci_dev *pdev, const struct pci_device_id *ent) +{ + struct drm_psb_private *dev_priv; + struct drm_device *dev; + int ret; + + ret = gma_remove_conflicting_framebuffers(pdev, &driver); if (ret) return ret; diff --git a/drivers/video/aperture.c b/drivers/video/aperture.c index e99f94b31ee4..ca1d13a99f3f 100644 --- a/drivers/video/aperture.c +++ b/drivers/video/aperture.c @@ -301,6 +301,37 @@ int aperture_remove_conflicting_devices(resource_size_t base, resource_size_t si } EXPORT_SYMBOL(aperture_remove_conflicting_devices); +/** + * __aperture_remove_legacy_vga_devices - remove legacy VGA devices of a PCI devices + * @pdev: PCI device + * + * This function removes VGA devices provided by @pdev, such as a VGA + * framebuffer or a console. This is useful if you have a VGA-compatible + * PCI graphics device with framebuffers in non-BAR locations. Drivers + * should acquire ownership of those memory areas and afterwards call + * this helper to release remaining VGA devices. + * + * If your hardware has its framebuffers accessible via PCI BARS, use + * aperture_remove_conflicting_pci_devices() instead. The function will + * release any VGA devices automatically. + * + * WARNING: Apparently we must remove graphics drivers before calling + * this helper. Otherwise the vga fbdev driver falls over if + * we have vgacon configured. + * + * Returns: + * 0 on success, or a negative errno code otherwise + */ +int __aperture_remove_legacy_vga_devices(struct pci_dev *pdev) +{ + /* VGA framebuffer */ + aperture_detach_devices(VGA_FB_PHYS_BASE, VGA_FB_PHYS_SIZE); + + /* VGA textmode console */ + return vga_remove_vgacon(pdev); +} +EXPORT_SYMBOL(__aperture_remove_legacy_vga_devices); + /** * aperture_remove_conflicting_pci_devices - remove existing framebuffers for PCI devices * @pdev: PCI device @@ -317,7 +348,7 @@ int aperture_remove_conflicting_pci_devices(struct pci_dev *pdev, const char *na { bool primary; resource_size_t base, size; - int bar, ret; + int bar, ret = 0; primary = pdev == vga_default_device(); @@ -333,24 +364,15 @@ int aperture_remove_conflicting_pci_devices(struct pci_dev *pdev, const char *na aperture_detach_devices(base, size); } - 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. - */ - ret = vga_remove_vgacon(pdev); - if (ret) - return ret; - } + /* + * 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) + ret = __aperture_remove_legacy_vga_devices(pdev); - return 0; + return ret; } EXPORT_SYMBOL(aperture_remove_conflicting_pci_devices); diff --git a/include/linux/aperture.h b/include/linux/aperture.h index 7248727753be..1a9a88b11584 100644 --- a/include/linux/aperture.h +++ b/include/linux/aperture.h @@ -16,6 +16,8 @@ int devm_aperture_acquire_for_platform_device(struct platform_device *pdev, int aperture_remove_conflicting_devices(resource_size_t base, resource_size_t size, const char *name); +int __aperture_remove_legacy_vga_devices(struct pci_dev *pdev); + int aperture_remove_conflicting_pci_devices(struct pci_dev *pdev, const char *name); #else static inline int devm_aperture_acquire_for_platform_device(struct platform_device *pdev, @@ -31,6 +33,11 @@ static inline int aperture_remove_conflicting_devices(resource_size_t base, reso return 0; } +static inline int __aperture_remove_legacy_vga_devices(struct pci_dev *pdev) +{ + return 0; +} + static inline int aperture_remove_conflicting_pci_devices(struct pci_dev *pdev, const char *name) { return 0; -- 2.40.0
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