3.16.57-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Ben Crocker <bcrocker@xxxxxxxxxx> commit 2c83029cda55a5e7665c7c6326909427d6a01350 upstream. 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@xxxxxxxxxx> Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx> Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx> --- drivers/gpu/drm/radeon/radeon_device.c | 4 ++++ 1 file changed, 4 insertions(+) --- a/drivers/gpu/drm/radeon/radeon_device.c +++ b/drivers/gpu/drm/radeon/radeon_device.c @@ -1339,6 +1339,10 @@ int radeon_device_init(struct radeon_dev if ((rdev->flags & RADEON_IS_PCI) && (rdev->family <= CHIP_RS740)) rdev->need_dma32 = true; +#ifdef CONFIG_PPC64 + if (rdev->family == CHIP_CEDAR) + rdev->need_dma32 = true; +#endif dma_bits = rdev->need_dma32 ? 32 : 40; r = pci_set_dma_mask(rdev->pdev, DMA_BIT_MASK(dma_bits));
