of: Add device tree selftests

Add some runtime test cases for the library of device tree parsing functions.

v2: - Add testcase for phandle with 0 args
    - Don't run testcases if testcase data isn't present in device tree

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

diff --git a/arch/arm/boot/dts/testcases/tests-phandle.dtsi b/arch/arm/boot/dts/testcases/tests-phandle.dtsi
new file mode 100644 (file)
index 0000000..ec0c4e6
--- /dev/null
+++ b/arch/arm/boot/dts/testcases/tests-phandle.dtsi
@@ -0,0 +1,37 @@
+
+/ {
+       testcase-data {
+               phandle-tests {
+                       provider0: provider0 {
+                               #phandle-cells = <0>;
+                       };
+
+                       provider1: provider1 {
+                               #phandle-cells = <1>;
+                       };
+
+                       provider2: provider2 {
+                               #phandle-cells = <2>;
+                       };
+
+                       provider3: provider3 {
+                               #phandle-cells = <3>;
+                       };
+
+                       consumer-a {
+                               phandle-list =  <&provider1 1>,
+                                               <&provider2 2 0>,
+                                               <0>,
+                                               <&provider3 4 4 3>,
+                                               <&provider2 5 100>,
+                                               <&provider0>,
+                                               <&provider1 7>;
+                               phandle-list-names = "first", "second", "third";
+
+                               phandle-list-bad-phandle = <12345678 0 0>;
+                               phandle-list-bad-args = <&provider2 1 0>,
+                                                       <&provider3 0>;
+                       };
+               };
+       };
+};

diff --git a/arch/arm/boot/dts/testcases/tests.dtsi b/arch/arm/boot/dts/testcases/tests.dtsi
new file mode 100644 (file)
index 0000000..a7c5067
--- /dev/null
+++ b/arch/arm/boot/dts/testcases/tests.dtsi
@@ -0,0 +1 @@
+/include/ "tests-phandle.dtsi"

diff --git a/arch/arm/boot/dts/versatile-pb.dts b/arch/arm/boot/dts/versatile-pb.dts
index 8a614e3..1664610 100644 (file)
--- a/arch/arm/boot/dts/versatile-pb.dts
+++ b/arch/arm/boot/dts/versatile-pb.dts
@@ -46,3 +46,5 @@
                };
        };
 };
+
+/include/ "testcases/tests.dtsi"

diff --git a/drivers/of/Kconfig b/drivers/of/Kconfig
index cac63c9..268163d 100644 (file)
--- a/drivers/of/Kconfig
+++ b/drivers/of/Kconfig
@@ -15,6 +15,15 @@ config PROC_DEVICETREE
          an image of the device tree that the kernel copies from Open
          Firmware or other boot firmware. If unsure, say Y here.
 
+config OF_SELFTEST
+       bool "Device Tree Runtime self tests"
+       help
+         This option builds in test cases for the device tree infrastructure
+         that are executed one at boot time, and the results dumped to the
+         console.
+
+         If unsure, say N here, but this option is safe to enable.
+
 config OF_FLATTREE
        bool
        select DTC

diff --git a/drivers/of/Makefile b/drivers/of/Makefile
index dccb117..a73f5a5 100644 (file)
--- a/drivers/of/Makefile
+++ b/drivers/of/Makefile
@@ -8,6 +8,7 @@ obj-$(CONFIG_OF_GPIO)   += gpio.o
 obj-$(CONFIG_OF_I2C)   += of_i2c.o
 obj-$(CONFIG_OF_NET)   += of_net.o
 obj-$(CONFIG_OF_SPI)   += of_spi.o
+obj-$(CONFIG_OF_SELFTEST) += selftest.o
 obj-$(CONFIG_OF_MDIO)  += of_mdio.o
 obj-$(CONFIG_OF_PCI)   += of_pci.o
 obj-$(CONFIG_OF_PCI_IRQ)  += of_pci_irq.o

diff --git a/drivers/of/selftest.c b/drivers/of/selftest.c
new file mode 100644 (file)
index 0000000..9d2b480
--- /dev/null
+++ b/drivers/of/selftest.c
@@ -0,0 +1,139 @@
+/*
+ * Self tests for device tree subsystem
+ */
+
+#define pr_fmt(fmt) "### %s(): " fmt, __func__
+
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/errno.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/list.h>
+#include <linux/mutex.h>
+#include <linux/slab.h>
+#include <linux/device.h>
+
+static bool selftest_passed = true;
+#define selftest(result, fmt, ...) { \
+       selftest_passed &= (result); \
+       if (!(result)) \
+               pr_err("FAIL %s:%i " fmt, __FILE__, __LINE__, ##__VA_ARGS__); \
+}
+
+static void __init of_selftest_parse_phandle_with_args(void)
+{
+       struct device_node *np;
+       struct of_phandle_args args;
+       int rc, i;
+       bool passed_all = true;
+
+       pr_info("start\n");
+       np = of_find_node_by_path("/testcase-data/phandle-tests/consumer-a");
+       if (!np) {
+               pr_err("missing testcase data\n");
+               return;
+       }
+
+       for (i = 0; i < 7; i++) {
+               bool passed = true;
+               rc = of_parse_phandle_with_args(np, "phandle-list",
+                                               "#phandle-cells", i, &args);
+
+               /* Test the values from tests-phandle.dtsi */
+               switch (i) {
+               case 0:
+                       passed &= !rc;
+                       passed &= (args.args_count == 1);
+                       passed &= (args.args[0] == (i + 1));
+                       break;
+               case 1:
+                       passed &= !rc;
+                       passed &= (args.args_count == 2);
+                       passed &= (args.args[0] == (i + 1));
+                       passed &= (args.args[1] == 0);
+                       break;
+               case 2:
+                       passed &= (rc == -ENOENT);
+                       break;
+               case 3:
+                       passed &= !rc;
+                       passed &= (args.args_count == 3);
+                       passed &= (args.args[0] == (i + 1));
+                       passed &= (args.args[1] == 4);
+                       passed &= (args.args[2] == 3);
+                       break;
+               case 4:
+                       passed &= !rc;
+                       passed &= (args.args_count == 2);
+                       passed &= (args.args[0] == (i + 1));
+                       passed &= (args.args[1] == 100);
+                       break;
+               case 5:
+                       passed &= !rc;
+                       passed &= (args.args_count == 0);
+                       break;
+               case 6:
+                       passed &= !rc;
+                       passed &= (args.args_count == 1);
+                       passed &= (args.args[0] == (i + 1));
+                       break;
+               case 7:
+                       passed &= (rc == -EINVAL);
+                       break;
+               default:
+                       passed = false;
+               }
+
+               if (!passed) {
+                       int j;
+                       pr_err("index %i - data error on node %s rc=%i regs=[",
+                               i, args.np->full_name, rc);
+                       for (j = 0; j < args.args_count; j++)
+                               printk(" %i", args.args[j]);
+                       printk(" ]\n");
+
+                       passed_all = false;
+               }
+       }
+
+       /* Check for missing list property */
+       rc = of_parse_phandle_with_args(np, "phandle-list-missing",
+                                       "#phandle-cells", 0, &args);
+       passed_all &= (rc == -EINVAL);
+
+       /* Check for missing cells property */
+       rc = of_parse_phandle_with_args(np, "phandle-list",
+                                       "#phandle-cells-missing", 0, &args);
+       passed_all &= (rc == -EINVAL);
+
+       /* Check for bad phandle in list */
+       rc = of_parse_phandle_with_args(np, "phandle-list-bad-phandle",
+                                       "#phandle-cells", 0, &args);
+       passed_all &= (rc == -EINVAL);
+
+       /* Check for incorrectly formed argument list */
+       rc = of_parse_phandle_with_args(np, "phandle-list-bad-args",
+                                       "#phandle-cells", 1, &args);
+       passed_all &= (rc == -EINVAL);
+
+       pr_info("end - %s\n", passed_all ? "PASS" : "FAIL");
+}
+
+static int __init of_selftest(void)
+{
+       struct device_node *np;
+
+       np = of_find_node_by_path("/testcase-data/phandle-tests/consumer-a");
+       if (!np) {
+               pr_info("No testcase data in device tree; not running tests\n");
+               return 0;
+       }
+       of_node_put(np);
+
+       pr_info("start of selftest - you will see error messages\n");
+       of_selftest_parse_phandle_with_args();
+       pr_info("end of selftest - %s\n", selftest_passed ? "PASS" : "FAIL");
+       return 0;
+}
+late_initcall(of_selftest);