On Wed, Feb 21, 2018 at 6:41 PM, Ben Crocker <bcrocker at redhat.com> 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. Can we make this ppc only? 40 bit DMA works fine on x86. Alex > > Signed-off-by: Ben Crocker <bcrocker at redhat.com> > --- > drivers/gpu/drm/radeon/radeon_device.c | 5 ++++- > 1 file changed, 4 insertions(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/radeon/radeon_device.c b/drivers/gpu/drm/radeon/radeon_device.c > index ffc10cadcf34..02538903830d 100644 > --- a/drivers/gpu/drm/radeon/radeon_device.c > +++ b/drivers/gpu/drm/radeon/radeon_device.c > @@ -1395,7 +1395,10 @@ int radeon_device_init(struct radeon_device *rdev, > if (rdev->flags & RADEON_IS_AGP) > rdev->need_dma32 = true; > if ((rdev->flags & RADEON_IS_PCI) && > - (rdev->family <= CHIP_RS740)) > + (rdev->family <= CHIP_RS740 || rdev->family == CHIP_CEDAR)) > + rdev->need_dma32 = true; > + if ((rdev->flags & RADEON_IS_PCIE) && > + (rdev->family == CHIP_CEDAR)) > rdev->need_dma32 = true; > > dma_bits = rdev->need_dma32 ? 32 : 40; > -- > 2.13.6 > > _______________________________________________ > dri-devel mailing list > dri-devel at lists.freedesktop.org > https://lists.freedesktop.org/mailman/listinfo/dri-devel
