| From 2c83029cda55a5e7665c7c6326909427d6a01350 Mon Sep 17 00:00:00 2001 |
| From: Ben Crocker <bcrocker@redhat.com> |
| Date: Thu, 22 Feb 2018 17:52:19 -0500 |
| Subject: drm/radeon: insist on 32-bit DMA for Cedar on PPC64/PPC64LE |
| |
| From: Ben Crocker <bcrocker@redhat.com> |
| |
| 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@redhat.com> |
| Signed-off-by: Alex Deucher <alexander.deucher@amd.com> |
| Cc: stable@vger.kernel.org |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| |
| --- |
| 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 |
| @@ -1397,6 +1397,10 @@ 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)); |