PCI: Fix endpoint DMA test for Linux v6.9

Building the PCI EPF DMA test driver for Linux v6.9 is failing because
the parameters for the pci_epf_alloc_space() function has been updated
to pass the alignment value via the 'pci_epc_features' structure instead
of passing the value directly.

Instead of hard-coding the endpoint alignment in the EPF DMA test driver
use the 'pcie_epc_get_features()' function to retrieve the endpoint
features structure which has the endpoint alignment.

By using the conftest script to detect the parameters for the
pci_epf_alloc_space() function, we can then pass the appropriate
arguments to the pci_epf_alloc_space() function.

Bug 4471899

Change-Id: Id80259a4c90d6f6ae2132cccbec1a96113d22be7
Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Reviewed-on: https://git-master.nvidia.com/r/c/linux-nv-oot/+/3116548
(cherry picked from commit 971680aadb)
Reviewed-on: https://git-master.nvidia.com/r/c/linux-nv-oot/+/3128431
Tested-by: Brad Griffis <bgriffis@nvidia.com>
GVS: Gerrit_Virtual_Submit <buildbot_gerritrpt@nvidia.com>
Reviewed-by: Brad Griffis <bgriffis@nvidia.com>

drivers/pci/endpoint/functions/pci-epf-dma-test.c

@@ -1,8 +1,8 @@
 // SPDX-License-Identifier: GPL-2.0+
+// SPDX-FileCopyrightText: Copyright (c) 2021-2024 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
+
 /*
  * PCIe DMA EPF test framework for Tegra PCIe
- *
- * Copyright (C) 2021-2024 NVIDIA Corporation. All rights reserved.
  */
 
 #include <nvidia/conftest.h>
@@ -207,6 +207,7 @@ static void pcie_dma_epf_unbind(struct pci_epf *epf)
 
 static int pcie_dma_epf_bind(struct pci_epf *epf)
 {
+	const struct pci_epc_features *epc_features;
 	struct pci_epc *epc = epf->epc;
 	struct pcie_epf_dma *epfnv = epf_get_drvdata(epf);
 	struct device *fdev = &epf->dev;
@@ -222,7 +223,19 @@ static int pcie_dma_epf_bind(struct pci_epf *epf)
 	epfnv->epf = epf;
 	epfnv->epc = epc;
 
-	epfnv->bar0_virt = lpci_epf_alloc_space(epf, BAR0_SIZE, BAR_0, SZ_64K);
+	epc_features = pci_epc_get_features(epc, epf->func_no, epf->vfunc_no);
+	if (!epc_features) {
+		dev_err(fdev, "Failed to get endpoint features!\n");
+		return -EINVAL;
+	}
+
+#if defined(NV_PCI_EPF_ALLOC_SPACE_HAS_EPC_FEATURES_ARG) /* Linux v6.9 */
+	epfnv->bar0_virt = lpci_epf_alloc_space(epf, BAR0_SIZE, BAR_0,
+						epc_features);
+#else
+	epfnv->bar0_virt = lpci_epf_alloc_space(epf, BAR0_SIZE, BAR_0,
+						epc_features->align);
+#endif
 	if (!epfnv->bar0_virt) {
 		dev_err(fdev, "Failed to allocate memory for BAR0\n");
 		return -ENOMEM;

scripts/conftest/Makefile

@@ -141,6 +141,7 @@ NV_CONFTEST_FUNCTION_COMPILE_TESTS += pwm_chip_struct_has_base_arg
 NV_CONFTEST_FUNCTION_COMPILE_TESTS += pwm_ops_struct_has_owner
 NV_CONFTEST_FUNCTION_COMPILE_TESTS += pci_disable_pcie_error_reporting
 NV_CONFTEST_FUNCTION_COMPILE_TESTS += pci_enable_pcie_error_reporting
+NV_CONFTEST_FUNCTION_COMPILE_TESTS += pci_epf_alloc_space_has_epc_features_arg
 NV_CONFTEST_FUNCTION_COMPILE_TESTS += pci_epf_driver_struct_probe_has_id_arg
 NV_CONFTEST_FUNCTION_COMPILE_TESTS += pci_epc_event_ops_struct_has_core_deinit
 NV_CONFTEST_FUNCTION_COMPILE_TESTS += pci_epc_irq_type_enum_present

scripts/conftest/conftest.sh

@@ -7321,6 +7321,28 @@ compile_test() {
             compile_check_conftest "$CODE" "NV_PCI_ENABLE_PCIE_ERROR_REPORTING_PRESENT" "" "functions"
         ;;
 
+        pci_epf_alloc_space_has_epc_features_arg)
+            #
+            # Determine if the function pci_epf_alloc_space() has a
+            # 'epc_features' argument.
+            #
+            # Commit e891becdccaa ("PCI: endpoint: Refactor
+            # pci_epf_alloc_space() API") updated the pci_epf_alloc_space()
+            # function to accept 'epc_features' as a parameter in Linux v6.9.
+            #
+            CODE="
+            #include <linux/pci-epc.h>
+            #include <linux/pci-epf.h>
+            void conftest_pci_epf_alloc_space_has_epc_features_arg(
+                    struct pci_epf *epf, size_t size, enum pci_barno bar,
+                    const struct pci_epc_features *epc_features,
+                    enum pci_epc_interface_type type) {
+                pci_epf_alloc_space(epf, size, bar, epc_features, type);
+            }"
+
+            compile_check_conftest "$CODE" "NV_PCI_EPF_ALLOC_SPACE_HAS_EPC_FEATURES_ARG" "" "types"
+        ;;
+
         pci_epf_driver_struct_probe_has_id_arg)
             #
             # Determine if the struct pci_epf_driver probe API has ID argument or not.