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 93cd57d20881ff3037186b20f7f6a407d5e7d58d..55e128ed82f00ae13b6fe9768cdbe56adbe8f9da 100644 (file)
--- 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