From: welu <Wei.Lu2@amd.com>
Date: Tue, 10 Apr 2018 17:33:17 -0400
Subject: drm/amdkfd: Try to enable atomics for all GPUs
Git-commit: 6106dce9559ec5a4b1a97302f2fcc508e40d2747
Patch-mainline: v4.18-rc1
References: FATE#326289 FATE#326079 FATE#326049 FATE#322398 FATE#326166

Report failure to enable atomics only on GPUs that require them.
This allows GPUs that don't require atomics to function, but can
benefit if they are available. This is the case for Vega10, which
doesn't use atomics for basic functioning of the MEC, AQL and HWS
microcode. So it can work without atomics. But shader programs can
still use atomic instructions on systems that support PCIe atomics.

Signed-off-by: welu <Wei.Lu2@amd.com>
Signed-off-by: Felix Kuehling <Felix.Kuehling@amd.com>
Reviewed-by: Oded Gabbay <oded.gabbay@gmail.com>
Signed-off-by: Oded Gabbay <oded.gabbay@gmail.com>
Acked-by: Petr Tesarik <ptesarik@suse.com>
---
 drivers/gpu/drm/amd/amdkfd/kfd_device.c |   27 +++++++++++++--------------
 1 file changed, 13 insertions(+), 14 deletions(-)

--- a/drivers/gpu/drm/amd/amdkfd/kfd_device.c
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_device.c
@@ -290,7 +290,7 @@ struct kfd_dev *kgd2kfd_probe(struct kgd
 	struct pci_dev *pdev, const struct kfd2kgd_calls *f2g)
 {
 	struct kfd_dev *kfd;
-
+	int ret;
 	const struct kfd_device_info *device_info =
 					lookup_device_info(pdev->device);
 
@@ -299,19 +299,18 @@ struct kfd_dev *kgd2kfd_probe(struct kgd
 		return NULL;
 	}
 
-	if (device_info->needs_pci_atomics) {
-		/* Allow BIF to recode atomics to PCIe 3.0
-		 * AtomicOps. 32 and 64-bit requests are possible and
-		 * must be supported.
-		 */
-		if (pci_enable_atomic_ops_to_root(pdev,
-				PCI_EXP_DEVCAP2_ATOMIC_COMP32 |
-				PCI_EXP_DEVCAP2_ATOMIC_COMP64) < 0) {
-			dev_info(kfd_device,
-				"skipped device %x:%x, PCI rejects atomics",
-				 pdev->vendor, pdev->device);
-			return NULL;
-		}
+	/* Allow BIF to recode atomics to PCIe 3.0 AtomicOps.
+	 * 32 and 64-bit requests are possible and must be
+	 * supported.
+	 */
+	ret = pci_enable_atomic_ops_to_root(pdev,
+			PCI_EXP_DEVCAP2_ATOMIC_COMP32 |
+			PCI_EXP_DEVCAP2_ATOMIC_COMP64);
+	if (device_info->needs_pci_atomics && ret < 0) {
+		dev_info(kfd_device,
+			 "skipped device %x:%x, PCI rejects atomics\n",
+			 pdev->vendor, pdev->device);
+		return NULL;
 	}
 
 	kfd = kzalloc(sizeof(*kfd), GFP_KERNEL);