On 2018-02-22 10:57 PM, Ben Crocker wrote: > In radeon_device_init, set the need_dma32 flag for Cedar chips > (e.g. FirePro 2270). This fixes, or at least works around, a bug > on PowerPC exposed by last year's commits > > 8e3f1b1d8255105f31556aacf8aeb6071b00d469 (Russell Currey) > > and > > 253fd51e2f533552ae35a0c661705da6c4842c1b (Alistair Popple) > > which enabled the 64-bit DMA iommu bypass. > > This caused the device to freeze, in some cases unrecoverably, and is > the subject of several bug reports internal to Red Hat. > > Signed-off-by: Ben Crocker <bcrocker at redhat.com> > --- > drivers/gpu/drm/radeon/radeon_device.c | 5 +++++ > 1 file changed, 5 insertions(+) > > diff --git a/drivers/gpu/drm/radeon/radeon_device.c b/drivers/gpu/drm/radeon/radeon_device.c > index ffc10cadcf34..ba7435bcd208 100644 > --- a/drivers/gpu/drm/radeon/radeon_device.c > +++ b/drivers/gpu/drm/radeon/radeon_device.c > @@ -1397,6 +1397,11 @@ int radeon_device_init(struct radeon_device *rdev, > if ((rdev->flags & RADEON_IS_PCI) && > (rdev->family <= CHIP_RS740)) > rdev->need_dma32 = true; > +#ifdef CONFIG_PPC64 > + if ((rdev->flags & (RADEON_IS_PCI | RADEON_IS_PCIE)) && Cedar is (like all Radeons from the last decade) always PCIe, so this flags check is redundant FWIW. -- Earthling Michel Dänzer | http://www.amd.com Libre software enthusiast | Mesa and X developer
