[PATCH] Revert "drm/radeon: handle PCIe root ports with addressing limitations"

[Alex Deucher]

This change breaks tons of systems.

This reverts commit 33b3ad3788aba846fc8b9a065fe2685a0b64f713.

Bug: https://bugzilla.kernel.org/show_bug.cgi?id=206973
Bug: https://bugzilla.kernel.org/show_bug.cgi?id=206697
Bug: https://bugzilla.kernel.org/show_bug.cgi?id=207763
Bug: https://gitlab.freedesktop.org/drm/amd/-/issues/1140
Bug: https://gitlab.freedesktop.org/drm/amd/-/issues/1287
Signed-off-by: Alex Deucher <alexander.deucher at amd.com>
Cc: stable at vger.kernel.org
Cc: Christoph Hellwig <hch at lst.de>
Cc: christian.koenig at amd.com
---
 drivers/gpu/drm/radeon/radeon.h        |  1 +
 drivers/gpu/drm/radeon/radeon_device.c | 13 ++++++++-----
 drivers/gpu/drm/radeon/radeon_ttm.c    |  2 +-
 3 files changed, 10 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/radeon/radeon.h b/drivers/gpu/drm/radeon/radeon.h
index b7c3fb2bfb54..eed23dffccf4 100644
--- a/drivers/gpu/drm/radeon/radeon.h
+++ b/drivers/gpu/drm/radeon/radeon.h
@@ -2391,6 +2391,7 @@ struct radeon_device {
 	struct radeon_wb		wb;
 	struct radeon_dummy_page	dummy_page;
 	bool				shutdown;
+	bool				need_dma32;
 	bool				need_swiotlb;
 	bool				accel_working;
 	bool				fastfb_working; /* IGP feature*/
diff --git a/drivers/gpu/drm/radeon/radeon_device.c b/drivers/gpu/drm/radeon/radeon_device.c
index 266e3cbbd09b..f74c74ad8b5d 100644
--- a/drivers/gpu/drm/radeon/radeon_device.c
+++ b/drivers/gpu/drm/radeon/radeon_device.c
@@ -1363,25 +1363,28 @@ int radeon_device_init(struct radeon_device *rdev,
 	else
 		rdev->mc.mc_mask = 0xffffffffULL; /* 32 bit MC */
 
-	/* set DMA mask.
+	/* set DMA mask + need_dma32 flags.
 	 * PCIE - can handle 40-bits.
 	 * IGP - can handle 40-bits
 	 * AGP - generally dma32 is safest
 	 * PCI - dma32 for legacy pci gart, 40 bits on newer asics
 	 */
-	dma_bits = 40;
+	rdev->need_dma32 = false;
 	if (rdev->flags & RADEON_IS_AGP)
-		dma_bits = 32;
+		rdev->need_dma32 = true;
 	if ((rdev->flags & RADEON_IS_PCI) &&
 	    (rdev->family <= CHIP_RS740))
-		dma_bits = 32;
+		rdev->need_dma32 = true;
 #ifdef CONFIG_PPC64
 	if (rdev->family == CHIP_CEDAR)
-		dma_bits = 32;
+		rdev->need_dma32 = true;
 #endif
 
+	dma_bits = rdev->need_dma32 ? 32 : 40;
 	r = dma_set_mask_and_coherent(&rdev->pdev->dev, DMA_BIT_MASK(dma_bits));
 	if (r) {
+		rdev->need_dma32 = true;
+		dma_bits = 32;
 		pr_warn("radeon: No suitable DMA available\n");
 		return r;
 	}
diff --git a/drivers/gpu/drm/radeon/radeon_ttm.c b/drivers/gpu/drm/radeon/radeon_ttm.c
index 357e8e98cca9..d2550862313e 100644
--- a/drivers/gpu/drm/radeon/radeon_ttm.c
+++ b/drivers/gpu/drm/radeon/radeon_ttm.c
@@ -787,7 +787,7 @@ int radeon_ttm_init(struct radeon_device *rdev)
 			       &radeon_bo_driver,
 			       rdev->ddev->anon_inode->i_mapping,
 			       rdev->ddev->vma_offset_manager,
-			       dma_addressing_limited(&rdev->pdev->dev));
+			       rdev->need_dma32);
 	if (r) {
 		DRM_ERROR("failed initializing buffer object driver(%d).\n", r);
 		return r;
-- 
2.25.4