From: Niklas Cassel <cassel@kernel.org>
Date: Thu, 12 Mar 2026 13:02:37 +0000 (+0100)
Subject: misc: pci_endpoint_test: Give reserved BARs a distinct error code
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=c3f33af67e6458f4e49d016429d7aeef3c8b8399;p=thirdparty%2Fkernel%2Flinux.git

misc: pci_endpoint_test: Give reserved BARs a distinct error code

Give reserved BARs a distinct error code, such that the pci_endpoint_test
selftest will be able to skip test cases that are run against reserved
BARs.

Signed-off-by: Niklas Cassel <cassel@kernel.org>
[mani: Used __fls(CAP_BAR0_RESERVED) instead of PCI_ENDPOINT_CAP_BAR0_RESERVED_BIT]
Signed-off-by: Manivannan Sadhasivam <mani@kernel.org>
Tested-by: Manikanta Maddireddy <mmaddireddy@nvidia.com>
Tested-by: Koichiro Den <den@valinux.co.jp>
Reviewed-by: Frank Li <Frank.Li@nxp.com>
Link: https://patch.msgid.link/20260312130229.2282001-21-cassel@kernel.org
---

diff --git a/drivers/misc/pci_endpoint_test.c b/drivers/misc/pci_endpoint_test.c
index 93cd57d20881f..55e128ed82f00 100644
--- a/drivers/misc/pci_endpoint_test.c
+++ b/drivers/misc/pci_endpoint_test.c
@@ -85,6 +85,12 @@
 #define CAP_INTX				BIT(3)
 #define CAP_SUBRANGE_MAPPING			BIT(4)
 #define CAP_DYNAMIC_INBOUND_MAPPING		BIT(5)
+#define CAP_BAR0_RESERVED			BIT(6)
+#define CAP_BAR1_RESERVED			BIT(7)
+#define CAP_BAR2_RESERVED			BIT(8)
+#define CAP_BAR3_RESERVED			BIT(9)
+#define CAP_BAR4_RESERVED			BIT(10)
+#define CAP_BAR5_RESERVED			BIT(11)
 
 #define PCI_ENDPOINT_TEST_DB_BAR		0x34
 #define PCI_ENDPOINT_TEST_DB_OFFSET		0x38
@@ -276,6 +282,11 @@ fail:
 	return ret;
 }
 
+static bool bar_is_reserved(struct pci_endpoint_test *test, enum pci_barno bar)
+{
+	return test->ep_caps & BIT(bar + __fls(CAP_BAR0_RESERVED));
+}
+
 static const u32 bar_test_pattern[] = {
 	0xA0A0A0A0,
 	0xA1A1A1A1,
@@ -404,7 +415,7 @@ static int pci_endpoint_test_bars(struct pci_endpoint_test *test)
 
 	/* Write all BARs in order (without reading). */
 	for (bar = 0; bar < PCI_STD_NUM_BARS; bar++)
-		if (test->bar[bar])
+		if (test->bar[bar] && !bar_is_reserved(test, bar))
 			pci_endpoint_test_bars_write_bar(test, bar);
 
 	/*
@@ -414,7 +425,7 @@ static int pci_endpoint_test_bars(struct pci_endpoint_test *test)
 	 * (Reading back the BAR directly after writing can not detect this.)
 	 */
 	for (bar = 0; bar < PCI_STD_NUM_BARS; bar++) {
-		if (test->bar[bar]) {
+		if (test->bar[bar] && !bar_is_reserved(test, bar)) {
 			ret = pci_endpoint_test_bars_read_bar(test, bar);
 			if (ret)
 				return ret;
@@ -1143,6 +1154,11 @@ static long pci_endpoint_test_ioctl(struct file *file, unsigned int cmd,
 		if (is_am654_pci_dev(pdev) && bar == BAR_0)
 			goto ret;
 
+		if (bar_is_reserved(test, bar)) {
+			ret = -ENOBUFS;
+			goto ret;
+		}
+
 		if (cmd == PCITEST_BAR)
 			ret = pci_endpoint_test_bar(test, bar);
 		else