| Message ID | 1453834196-5741-3-git-send-email-daniel.vetter@ffwll.ch (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Tue, Jan 26, 2016 at 07:49:56PM +0100, Daniel Vetter wrote: > The fake agp driver for the intel graphics gart is only needed for ums > support. And we ditched that a long time ago: > > commit 03dae59c72ffffd8ef6e005f48ba356c863e0587 > Author: Daniel Vetter <daniel.vetter@ffwll.ch> > Date: Wed Jul 23 16:27:25 2014 +0200 > > drm/i915: Ditch UMS config option > > With this there's no longer the problem that 2 drivers (fake agp > driver and the drm/i915 driver) fight over the same piece, which fixes > apparent dma leaks detected by CONFIG_DMA_API_DEBUG. > > Note that the leak isn't real since intel-gtt refcounts and will tear > down eventually. But the debug code assumes that when the i915 driver > unbinds from the pci device everything should be gone. Which isn't the > case if we have intel-agp enabled - userspace might need it. But by > ditching this intel-gtt setup and teardown is completely tied to the > livetime of the "real" driver. > > While at it untangle the init ordering a bit - the fake agp wouldn't > be initialized correctly if i915.ko loads first. Which isn't a problem > since when i915 loads in kms mode you won't need the fake agp support > needed by the ums driver ... > > Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=93793 > Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> -Chris
diff --git a/drivers/char/agp/intel-gtt.c b/drivers/char/agp/intel-gtt.c index 432ae61a8715..1b5e07258d80 100644 --- a/drivers/char/agp/intel-gtt.c +++ b/drivers/char/agp/intel-gtt.c @@ -1346,16 +1346,6 @@ int intel_gmch_probe(struct pci_dev *bridge_pdev, struct pci_dev *gpu_pdev, { int i, mask; - /* - * Can be called from the fake agp driver but also directly from - * drm/i915.ko. Hence we need to check whether everything is set up - * already. - */ - if (intel_private.driver) { - intel_private.refcount++; - return 1; - } - for (i = 0; intel_gtt_chipsets[i].name != NULL; i++) { if (gpu_pdev) { if (gpu_pdev->device == @@ -1376,16 +1366,26 @@ int intel_gmch_probe(struct pci_dev *bridge_pdev, struct pci_dev *gpu_pdev, if (!intel_private.driver) return 0; - intel_private.refcount++; - #if IS_ENABLED(CONFIG_AGP_INTEL) if (bridge) { + if (INTEL_GTT_GEN > 1) + return 0; + bridge->driver = &intel_fake_agp_driver; bridge->dev_private_data = &intel_private; bridge->dev = bridge_pdev; } #endif + + /* + * Can be called from the fake agp driver but also directly from + * drm/i915.ko. Hence we need to check whether everything is set up + * already. + */ + if (intel_private.refcount++) + return 1; + intel_private.bridge_dev = pci_dev_get(bridge_pdev); dev_info(&bridge_pdev->dev, "Intel %s Chipset\n", intel_gtt_chipsets[i].name);
The fake agp driver for the intel graphics gart is only needed for ums support. And we ditched that a long time ago: commit 03dae59c72ffffd8ef6e005f48ba356c863e0587 Author: Daniel Vetter <daniel.vetter@ffwll.ch> Date: Wed Jul 23 16:27:25 2014 +0200 drm/i915: Ditch UMS config option With this there's no longer the problem that 2 drivers (fake agp driver and the drm/i915 driver) fight over the same piece, which fixes apparent dma leaks detected by CONFIG_DMA_API_DEBUG. Note that the leak isn't real since intel-gtt refcounts and will tear down eventually. But the debug code assumes that when the i915 driver unbinds from the pci device everything should be gone. Which isn't the case if we have intel-agp enabled - userspace might need it. But by ditching this intel-gtt setup and teardown is completely tied to the livetime of the "real" driver. While at it untangle the init ordering a bit - the fake agp wouldn't be initialized correctly if i915.ko loads first. Which isn't a problem since when i915 loads in kms mode you won't need the fake agp support needed by the ums driver ... Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=93793 Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> --- drivers/char/agp/intel-gtt.c | 24 ++++++++++++------------ 1 file changed, 12 insertions(+), 12 deletions(-)