When the linux kernel is build with (typical kernel ship with Debian installer):
CONFIG_FB=y 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, see commit a56f7428d753 ("drm/radeon: Add early unregister of firmware fb's").
Signed-off-by: Mathieu Malaterre malat@debian.org Link: https://bugs.debian.org/826629#57 Link: https://bugzilla.kernel.org/show_bug.cgi?id=119741 Suggested-by: Lennart Sorensen lsorense@csclub.uwaterloo.ca Cc: Bartlomiej Zolnierkiewicz b.zolnierkie@samsung.com Cc: Benjamin Herrenschmidt benh@kernel.crashing.org Cc: Tomi Valkeinen tomi.valkeinen@ti.com --- 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. v4: Use drm_fb_helper_remove_conflicting_framebuffers from drm_fb_helper v5: do not use drm_fb_helper_remove_conflicting_framebuffers from drm_fb_helper remove ifdef hacks since not needed once framebuffer is properly decremented
drivers/video/fbdev/aty/radeon_base.c | 21 +++++++++++++++++++++ 1 file changed, 21 insertions(+)
diff --git a/drivers/video/fbdev/aty/radeon_base.c b/drivers/video/fbdev/aty/radeon_base.c index 87608c0b2351..e8594bbaea60 100644 --- a/drivers/video/fbdev/aty/radeon_base.c +++ b/drivers/video/fbdev/aty/radeon_base.c @@ -2255,6 +2255,23 @@ 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) @@ -2308,6 +2325,10 @@ 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) {