On Thursday, December 21, 2017 11:07:56 PM Mathieu Malaterre wrote: > When the linux kernel is build with (typical kernel ship with Debian > installer): > > CONFIG_FB_OF=y > CONFIG_VT_HW_CONSOLE_BINDING=y > CONFIG_FB_RADEON=m > > The offb driver takes precedence over module radeonfb. It is then > impossible to load the module, error reported is: > > [ 96.551486] radeonfb 0000:00:10.0: enabling device (0006 -> 0007) > [ 96.551526] radeonfb 0000:00:10.0: BAR 0: can't reserve [mem 0x98000000-0x9fffffff pref] > [ 96.551531] radeonfb (0000:00:10.0): cannot request region 0. > [ 96.551545] radeonfb: probe of 0000:00:10.0 failed with error -16 > > This patch reproduce the behavior of the module radeon, so as to make it > possible to load radeonfb when offb is first loaded. > > It should be noticed that `offb_destroy` is never called which explain the > need to skip error detection on the radeon side. This still needs to be explained more, from my last mail: "The last put_fb_info() on fb_info should call ->fb_destroy (offb_destroy in our case) and remove_conflicting_framebuffers() is calling put_fb_info() so there is some extra reference on fb_info somewhere preventing it from going away. Please look into fixing this." > Signed-off-by: Mathieu Malaterre <malat@xxxxxxxxxx> > Link: https://bugs.debian.org/826629#57 > Link: https://bugzilla.kernel.org/show_bug.cgi?id=119741 > Suggested-by: Lennart Sorensen <lsorense@xxxxxxxxxxxxxxxxxxx> > --- > v2: Only fails when CONFIG_PCC is not set > v3: Only fails when CONFIG_FB_OF is not set, CONFIG_PCC was too broad. Since the conflicts in region is due to OFfb explicitly refers to it. It seems that there may still be configurations when this is incorrect -> when offb drives primary (non-radeon) card and radeonfb drives secondary (radeon) card.. > drivers/video/fbdev/aty/radeon_base.c | 26 ++++++++++++++++++++++++++ > 1 file changed, 26 insertions(+) > > diff --git a/drivers/video/fbdev/aty/radeon_base.c b/drivers/video/fbdev/aty/radeon_base.c > index 4d77daeecf99..221879196531 100644 > --- a/drivers/video/fbdev/aty/radeon_base.c > +++ b/drivers/video/fbdev/aty/radeon_base.c > @@ -2259,6 +2259,22 @@ static const struct bin_attribute edid2_attr = { > .read = radeon_show_edid2, > }; > > +static int radeon_kick_out_firmware_fb(struct pci_dev *pdev) > +{ > + struct apertures_struct *ap; > + > + ap = alloc_apertures(1); > + if (!ap) > + return -ENOMEM; > + > + ap->ranges[0].base = pci_resource_start(pdev, 0); > + ap->ranges[0].size = pci_resource_len(pdev, 0); > + > + remove_conflicting_framebuffers(ap, KBUILD_MODNAME, false); > + kfree(ap); > + > + return 0; > +} > > static int radeonfb_pci_register(struct pci_dev *pdev, > const struct pci_device_id *ent) > @@ -2312,19 +2328,27 @@ static int radeonfb_pci_register(struct pci_dev *pdev, > rinfo->fb_base_phys = pci_resource_start (pdev, 0); > rinfo->mmio_base_phys = pci_resource_start (pdev, 2); > > + ret = radeon_kick_out_firmware_fb(pdev); > + if (ret) > + return ret; > + > /* request the mem regions */ > ret = pci_request_region(pdev, 0, "radeonfb framebuffer"); > if (ret < 0) { > +#ifndef CONFIG_FB_OF > printk( KERN_ERR "radeonfb (%s): cannot request region 0.\n", > pci_name(rinfo->pdev)); > goto err_release_fb; > +#endif > } > > ret = pci_request_region(pdev, 2, "radeonfb mmio"); > if (ret < 0) { > +#ifndef CONFIG_FB_OF > printk( KERN_ERR "radeonfb (%s): cannot request region 2.\n", > pci_name(rinfo->pdev)); > goto err_release_pci0; > +#endif > } > > /* map the regions */ > @@ -2509,10 +2533,12 @@ static int radeonfb_pci_register(struct pci_dev *pdev, > iounmap(rinfo->mmio_base); > err_release_pci2: > pci_release_region(pdev, 2); > +#ifndef CONFIG_FB_OF > err_release_pci0: > pci_release_region(pdev, 0); > err_release_fb: > framebuffer_release(info); > +#endif > err_disable: > err_out: > return ret; Best regards, -- Bartlomiej Zolnierkiewicz Samsung R&D Institute Poland Samsung Electronics _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel