4.14-stable review patch. If anyone has any objections, please let me know.
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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));