Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 38f53593 authored by Ard Biesheuvel's avatar Ard Biesheuvel Committed by Ben Skeggs
Browse files

drm/nouveau/pci: set streaming DMA mask early 



Some subdevices (i.e., fb/nv50.c and fb/gf100.c) map a scratch page using
dma_map_page() way before the TTM layer has had a chance to set the DMA
mask. This may prevent the driver from loading at all on platforms whose
system memory is not covered by the default DMA mask of 32-bit (i.e., when
all RAM is above 4 GB).

So set a preliminary DMA mask right after constructing the PCI device, and
base it on the .dma_bits member of the MMU subdevice, which is what the TTM
layer will base the DMA mask on as well.

Signed-off-by: default avatarArd Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: default avatarBen Skeggs <bskeggs@redhat.com>
parent bbe1f94a

drivers/gpu/drm/nouveau/nvkm/engine/device/pci.c

+27 −10
Original line number Diff line number Diff line
@@ -1664,7 +1664,7 @@ nvkm_device_pci_new(struct pci_dev *pci_dev, const char *cfg, const char *dbg, 
	*pdevice = &pdev->device;

	pdev->pdev = pci_dev;



	return nvkm_device_ctor(&nvkm_device_pci_func, quirk, &pci_dev->dev,

	ret = nvkm_device_ctor(&nvkm_device_pci_func, quirk, &pci_dev->dev,

			       pci_is_pcie(pci_dev) ? NVKM_DEVICE_PCIE :

			       pci_find_capability(pci_dev, PCI_CAP_ID_AGP) ?

			       NVKM_DEVICE_AGP : NVKM_DEVICE_PCI,
@@ -1674,4 +1674,21 @@ nvkm_device_pci_new(struct pci_dev *pci_dev, const char *cfg, const char *dbg, 
				    PCI_FUNC(pci_dev->devfn), name,

			       cfg, dbg, detect, mmio, subdev_mask,

			       &pdev->device);



	if (ret)

		return ret;



	/*

	 * Set a preliminary DMA mask based on the .dma_bits member of the

	 * MMU subdevice. This allows other subdevices to create DMA mappings

	 * in their init() or oneinit() methods, which may be called before the

	 * TTM layer sets the DMA mask definitively.

	 * This is necessary for platforms where the default DMA mask of 32

	 * does not cover any system memory, i.e., when all RAM is > 4 GB.

	 */

	if (subdev_mask & BIT(NVKM_SUBDEV_MMU))

		dma_set_mask_and_coherent(&pci_dev->dev,

				DMA_BIT_MASK(pdev->device.mmu->dma_bits));



	return 0;

}