[PATCH] drm/amdkfd: register HMM dev memory to DMA-able range first

[francisco_flynn]

HMM device memory is allocated at the top of
iomem_resource, when iomem_resource is larger than
GPU device's dma mask, after devm_memremap_pages,
max_pfn will also be update and exceed device's
dma mask, when there are multiple card on system
need to be init, ttm_device_init would be called
with use_dma32=true, and this is not necessary at
all. let's request dev memory region at DMA-able
range first.

Signed-off-by: francisco_flynn <francisco_flynn at foxmail.com>
---
 drivers/gpu/drm/amd/amdkfd/kfd_migrate.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_migrate.c b/drivers/gpu/drm/amd/amdkfd/kfd_migrate.c
index 79251f22b702..3856b9fd2a70 100644
--- a/drivers/gpu/drm/amd/amdkfd/kfd_migrate.c
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_migrate.c
@@ -1020,6 +1020,7 @@ int kgd2kfd_init_zone_device(struct amdgpu_device *adev)
 	struct amdgpu_kfd_dev *kfddev = &adev->kfd;
 	struct dev_pagemap *pgmap;
 	struct resource *res = NULL;
+	struct resource temp_res = iomem_resource;
 	unsigned long size;
 	void *r;
 
@@ -1042,7 +1043,10 @@ int kgd2kfd_init_zone_device(struct amdgpu_device *adev)
 		pgmap->range.end = adev->gmc.aper_base + adev->gmc.aper_size - 1;
 		pgmap->type = MEMORY_DEVICE_COHERENT;
 	} else {
-		res = devm_request_free_mem_region(adev->dev, &iomem_resource, size);
+		temp_res.end = dma_get_mask(adev->dev);
+		res = devm_request_free_mem_region(adev->dev, &temp_res, size);
+		if (IS_ERR(res))
+			res = devm_request_free_mem_region(adev->dev, &iomem_resource, size);
 		if (IS_ERR(res))
 			return PTR_ERR(res);
 		pgmap->range.start = res->start;
-- 
2.25.1