PCI: endpoint: Allocate enough space for fixed size BAR

PCI endpoint test function code should honor the .bar_fixed_size parameter
from underlying endpoint controller drivers or results may be unexpected.

In pci_epf_test_alloc_space(), check if BAR being used for test
register space is a fixed size BAR. If so, allocate the required fixed
size.

Signed-off-by: Alan Mikhak <alan.mikhak@sifive.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Kishon Vijay Abraham I <kishon@ti.com>

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

@@ -434,10 +434,16 @@ static int pci_epf_test_alloc_space(struct pci_epf *epf)
 	int bar;
 	enum pci_barno test_reg_bar = epf_test->test_reg_bar;
 	const struct pci_epc_features *epc_features;
+	size_t test_reg_size;
 
 	epc_features = epf_test->epc_features;
 
-	base = pci_epf_alloc_space(epf, sizeof(struct pci_epf_test_reg),
+	if (epc_features->bar_fixed_size[test_reg_bar])
+		test_reg_size = bar_size[test_reg_bar];
+	else
+		test_reg_size = sizeof(struct pci_epf_test_reg);
+
+	base = pci_epf_alloc_space(epf, test_reg_size,
 				   test_reg_bar, epc_features->align);
 	if (!base) {
 		dev_err(dev, "Failed to allocated register space\n");