of: Add unit tests for applying overlays
authorFrank Rowand <frank.rowand@sony.com>
Wed, 26 Apr 2017 00:09:54 +0000 (17:09 -0700)
committerRob Herring <robh@kernel.org>
Thu, 27 Apr 2017 22:26:06 +0000 (17:26 -0500)
Existing overlay unit tests examine individual pieces of the overlay
code.  The new tests target the entire process of applying an overlay.

Signed-off-by: Frank Rowand <frank.rowand@sony.com>
Signed-off-by: Rob Herring <robh@kernel.org>
drivers/of/fdt.c
drivers/of/of_private.h
drivers/of/unittest-data/Makefile
drivers/of/unittest-data/overlay.dts [new file with mode: 0644]
drivers/of/unittest-data/overlay_bad_phandle.dts [new file with mode: 0644]
drivers/of/unittest-data/overlay_base.dts [new file with mode: 0644]
drivers/of/unittest.c

index e5ce4b59e16282cc1240514beec867ae8664e052..e33f7818bc6c7b794151eeffaac810aef4add78a 100644 (file)
@@ -31,6 +31,8 @@
 #include <asm/setup.h>  /* for COMMAND_LINE_SIZE */
 #include <asm/page.h>
 
+#include "of_private.h"
+
 /*
  * of_fdt_limit_memory - limit the number of regions in the /memory node
  * @limit: maximum entries
@@ -469,11 +471,11 @@ static int unflatten_dt_nodes(const void *blob,
  * Returns NULL on failure or the memory chunk containing the unflattened
  * device tree on success.
  */
-static void *__unflatten_device_tree(const void *blob,
-                                    struct device_node *dad,
-                                    struct device_node **mynodes,
-                                    void *(*dt_alloc)(u64 size, u64 align),
-                                    bool detached)
+void *__unflatten_device_tree(const void *blob,
+                             struct device_node *dad,
+                             struct device_node **mynodes,
+                             void *(*dt_alloc)(u64 size, u64 align),
+                             bool detached)
 {
        int size;
        void *mem;
@@ -1261,6 +1263,8 @@ void __init unflatten_device_tree(void)
 
        /* Get pointer to "/chosen" and "/aliases" nodes for use everywhere */
        of_alias_scan(early_init_dt_alloc_memory_arch);
+
+       unittest_unflatten_overlay_base();
 }
 
 /**
index 18bbb4517e2580afe31a7dc30997d30dd986a50c..de5c604f5cc42c4eccdee4af17fbbeb626abb0f3 100644 (file)
@@ -55,6 +55,18 @@ static inline int of_property_notify(int action, struct device_node *np,
 }
 #endif /* CONFIG_OF_DYNAMIC */
 
+#ifdef CONFIG_OF_UNITTEST
+extern void __init unittest_unflatten_overlay_base(void);
+#else
+static inline void unittest_unflatten_overlay_base(void) {};
+#endif
+
+extern void *__unflatten_device_tree(const void *blob,
+                             struct device_node *dad,
+                             struct device_node **mynodes,
+                             void *(*dt_alloc)(u64 size, u64 align),
+                             bool detached);
+
 /**
  * General utilities for working with live trees.
  *
index 1ac5cc01d6273019bcbaed27902c63cffb50449e..6e00a9c69e584bf5ee9067b6a662f0ed0b2ca0db 100644 (file)
@@ -1,7 +1,18 @@
 obj-y += testcases.dtb.o
+obj-y += overlay.dtb.o
+obj-y += overlay_bad_phandle.dtb.o
+obj-y += overlay_base.dtb.o
 
 targets += testcases.dtb testcases.dtb.S
+targets += overlay.dtb overlay.dtb.S
+targets += overlay_bad_phandle.dtb overlay_bad_phandle.dtb.S
+targets += overlay_base.dtb overlay_base.dtb.S
 
-.SECONDARY: \
-       $(obj)/testcases.dtb.S \
-       $(obj)/testcases.dtb
+.PRECIOUS: \
+       $(obj)/%.dtb.S \
+       $(obj)/%.dtb
+
+# enable creation of __symbols__ node
+DTC_FLAGS_overlay := -@
+DTC_FLAGS_overlay_bad_phandle := -@
+DTC_FLAGS_overlay_base := -@
diff --git a/drivers/of/unittest-data/overlay.dts b/drivers/of/unittest-data/overlay.dts
new file mode 100644 (file)
index 0000000..6cd7e6a
--- /dev/null
@@ -0,0 +1,53 @@
+/dts-v1/;
+/plugin/;
+
+/ {
+
+       fragment@0 {
+               target = <&electric_1>;
+
+               __overlay__ {
+                       status = "ok";
+
+                       hvac_2: hvac-large-1 {
+                               compatible = "ot,hvac-large";
+                               heat-range = < 40 75 >;
+                               cool-range = < 65 80 >;
+                       };
+               };
+       };
+
+       fragment@1 {
+               target = <&rides_1>;
+
+               __overlay__ {
+                       #address-cells = <1>;
+                       #size-cells = <1>;
+                       status = "ok";
+
+                       ride@200 {
+                               compatible = "ot,ferris-wheel";
+                               reg = < 0x00000200 0x100 >;
+                               hvac-provider = < &hvac_2 >;
+                               hvac-thermostat = < 27 32 > ;
+                               hvac-zones = < 12 5 >;
+                               hvac-zone-names = "operator", "snack-bar";
+                               spin-controller = < &spin_ctrl_1 3 >;
+                               spin-rph = < 30 >;
+                               gondolas = < 16 >;
+                               gondola-capacity = < 6 >;
+                       };
+               };
+       };
+
+       fragment@2 {
+               target = <&lights_2>;
+
+               __overlay__ {
+                       status = "ok";
+                       color = "purple", "white", "red", "green";
+                       rate = < 3 256 >;
+               };
+       };
+
+};
diff --git a/drivers/of/unittest-data/overlay_bad_phandle.dts b/drivers/of/unittest-data/overlay_bad_phandle.dts
new file mode 100644 (file)
index 0000000..270ee88
--- /dev/null
@@ -0,0 +1,20 @@
+/dts-v1/;
+/plugin/;
+
+/ {
+
+       fragment@0 {
+               target = <&electric_1>;
+
+               __overlay__ {
+
+                       // This label should cause an error when the overlay
+                       // is applied.  There is already a phandle value
+                       // in the base tree for motor-1.
+                       spin_ctrl_1_conflict: motor-1 {
+                               accelerate = < 3 >;
+                               decelerate = < 5 >;
+                       };
+               };
+       };
+};
diff --git a/drivers/of/unittest-data/overlay_base.dts b/drivers/of/unittest-data/overlay_base.dts
new file mode 100644 (file)
index 0000000..5566b27
--- /dev/null
@@ -0,0 +1,80 @@
+/dts-v1/;
+/plugin/;
+
+/*
+ * Base device tree that overlays will be applied against.
+ *
+ * Do not add any properties in node "/".
+ * Do not add any nodes other than "/testcase-data-2" in node "/".
+ * Do not add anything that would result in dtc creating node "/__fixups__".
+ * dtc will create nodes "/__symbols__" and "/__local_fixups__".
+ */
+
+/ {
+       testcase-data-2 {
+               #address-cells = <1>;
+               #size-cells = <1>;
+
+               electric_1: substation@100 {
+                       compatible = "ot,big-volts-control";
+                       reg = < 0x00000100 0x100 >;
+                       status = "disabled";
+
+                       hvac_1: hvac-medium-1 {
+                               compatible = "ot,hvac-medium";
+                               heat-range = < 50 75 >;
+                               cool-range = < 60 80 >;
+                       };
+
+                       spin_ctrl_1: motor-1 {
+                               compatible = "ot,ferris-wheel-motor";
+                               spin = "clockwise";
+                       };
+
+                       spin_ctrl_2: motor-8 {
+                               compatible = "ot,roller-coaster-motor";
+                       };
+               };
+
+               rides_1: fairway-1 {
+                       #address-cells = <1>;
+                       #size-cells = <1>;
+                       compatible = "ot,rides";
+                       status = "disabled";
+                       orientation = < 127 >;
+
+                       ride@100 {
+                               compatible = "ot,roller-coaster";
+                               reg = < 0x00000100 0x100 >;
+                               hvac-provider = < &hvac_1 >;
+                               hvac-thermostat = < 29 > ;
+                               hvac-zones = < 14 >;
+                               hvac-zone-names = "operator";
+                               spin-controller = < &spin_ctrl_2 5 &spin_ctrl_2 7 >;
+                               spin-controller-names = "track_1", "track_2";
+                               queues = < 2 >;
+                       };
+               };
+
+               lights_1: lights@30000 {
+                       compatible = "ot,work-lights";
+                       reg = < 0x00030000 0x1000 >;
+                       status = "disabled";
+               };
+
+               lights_2: lights@40000 {
+                       compatible = "ot,show-lights";
+                       reg = < 0x00040000 0x1000 >;
+                       status = "disabled";
+                       rate = < 13 138 >;
+               };
+
+               retail_1: vending@50000 {
+                       reg = < 0x00050000 0x1000 >;
+                       compatible = "ot,tickets";
+                       status = "disabled";
+               };
+
+       };
+};
+
index 62db55b97c10bb5f511bd83d9ab4850d3d4db381..12597ff8cfb0b05e619add7c4e731ce890302f8b 100644 (file)
@@ -8,6 +8,7 @@
 #include <linux/err.h>
 #include <linux/errno.h>
 #include <linux/hashtable.h>
+#include <linux/libfdt.h>
 #include <linux/of.h>
 #include <linux/of_fdt.h>
 #include <linux/of_irq.h>
@@ -1925,6 +1926,320 @@ out:
 static inline void __init of_unittest_overlay(void) { }
 #endif
 
+/*
+ * __dtb_ot_begin[] and __dtb_ot_end[] are created by cmd_dt_S_dtb
+ * in scripts/Makefile.lib
+ */
+
+#define OVERLAY_INFO_EXTERN(name) \
+       extern uint8_t __dtb_##name##_begin[]; \
+       extern uint8_t __dtb_##name##_end[]
+
+#define OVERLAY_INFO(name, expected) \
+{      .dtb_begin       = __dtb_##name##_begin, \
+       .dtb_end         = __dtb_##name##_end, \
+       .expected_result = expected, \
+}
+
+struct overlay_info {
+       uint8_t            *dtb_begin;
+       uint8_t            *dtb_end;
+       void               *data;
+       struct device_node *np_overlay;
+       int                expected_result;
+       int                overlay_id;
+};
+
+OVERLAY_INFO_EXTERN(overlay_base);
+OVERLAY_INFO_EXTERN(overlay);
+OVERLAY_INFO_EXTERN(overlay_bad_phandle);
+
+#ifdef CONFIG_OF_OVERLAY
+
+/* order of entries is hard-coded into users of overlays[] */
+static struct overlay_info overlays[] = {
+       OVERLAY_INFO(overlay_base, -9999),
+       OVERLAY_INFO(overlay, 0),
+       OVERLAY_INFO(overlay_bad_phandle, -EINVAL),
+       {}
+};
+
+static struct device_node *overlay_base_root;
+
+/*
+ * Create base device tree for the overlay unittest.
+ *
+ * This is called from very early boot code.
+ *
+ * Do as much as possible the same way as done in __unflatten_device_tree
+ * and other early boot steps for the normal FDT so that the overlay base
+ * unflattened tree will have the same characteristics as the real tree
+ * (such as having memory allocated by the early allocator).  The goal
+ * is to test "the real thing" as much as possible, and test "test setup
+ * code" as little as possible.
+ *
+ * Have to stop before resolving phandles, because that uses kmalloc.
+ */
+void __init unittest_unflatten_overlay_base(void)
+{
+       struct overlay_info *info;
+       u32 data_size;
+       u32 size;
+
+       info = &overlays[0];
+
+       if (info->expected_result != -9999) {
+               pr_err("No dtb 'overlay_base' to attach\n");
+               return;
+       }
+
+       data_size = info->dtb_end - info->dtb_begin;
+       if (!data_size) {
+               pr_err("No dtb 'overlay_base' to attach\n");
+               return;
+       }
+
+       size = fdt_totalsize(info->dtb_begin);
+       if (size != data_size) {
+               pr_err("dtb 'overlay_base' header totalsize != actual size");
+               return;
+       }
+
+       info->data = early_init_dt_alloc_memory_arch(size,
+                                            roundup_pow_of_two(FDT_V17_SIZE));
+       if (!info->data) {
+               pr_err("alloc for dtb 'overlay_base' failed");
+               return;
+       }
+
+       memcpy(info->data, info->dtb_begin, size);
+
+       __unflatten_device_tree(info->data, NULL, &info->np_overlay,
+                               early_init_dt_alloc_memory_arch, true);
+       overlay_base_root = info->np_overlay;
+}
+
+/*
+ * The purpose of of_unittest_overlay_data_add is to add an
+ * overlay in the normal fashion.  This is a test of the whole
+ * picture, instead of testing individual elements.
+ *
+ * A secondary purpose is to be able to verify that the contents of
+ * /proc/device-tree/ contains the updated structure and values from
+ * the overlay.  That must be verified separately in user space.
+ *
+ * Return 0 on unexpected error.
+ */
+static int __init overlay_data_add(int onum)
+{
+       struct overlay_info *info;
+       int k;
+       int ret;
+       u32 size;
+       u32 size_from_header;
+
+       for (k = 0, info = overlays; info; info++, k++) {
+               if (k == onum)
+                       break;
+       }
+       if (onum > k)
+               return 0;
+
+       size = info->dtb_end - info->dtb_begin;
+       if (!size) {
+               pr_err("no overlay to attach, %d\n", onum);
+               ret = 0;
+       }
+
+       size_from_header = fdt_totalsize(info->dtb_begin);
+       if (size_from_header != size) {
+               pr_err("overlay header totalsize != actual size, %d", onum);
+               return 0;
+       }
+
+       /*
+        * Must create permanent copy of FDT because of_fdt_unflatten_tree()
+        * will create pointers to the passed in FDT in the EDT.
+        */
+       info->data = kmemdup(info->dtb_begin, size, GFP_KERNEL);
+       if (!info->data) {
+               pr_err("unable to allocate memory for data, %d\n", onum);
+               return 0;
+       }
+
+       of_fdt_unflatten_tree(info->data, NULL, &info->np_overlay);
+       if (!info->np_overlay) {
+               pr_err("unable to unflatten overlay, %d\n", onum);
+               ret = 0;
+               goto out_free_data;
+       }
+       of_node_set_flag(info->np_overlay, OF_DETACHED);
+
+       ret = of_resolve_phandles(info->np_overlay);
+       if (ret) {
+               pr_err("resolve ot phandles (ret=%d), %d\n", ret, onum);
+               goto out_free_np_overlay;
+       }
+
+       ret = of_overlay_create(info->np_overlay);
+       if (ret < 0) {
+               pr_err("of_overlay_create() (ret=%d), %d\n", ret, onum);
+               goto out_free_np_overlay;
+       } else {
+               info->overlay_id = ret;
+               ret = 0;
+       }
+
+       pr_debug("__dtb_overlay_begin applied, overlay id %d\n", ret);
+
+       goto out;
+
+out_free_np_overlay:
+       /*
+        * info->np_overlay is the unflattened device tree
+        * It has not been spliced into the live tree.
+        */
+
+       /* todo: function to free unflattened device tree */
+
+out_free_data:
+       kfree(info->data);
+
+out:
+       return (ret == info->expected_result);
+}
+
+/*
+ * The purpose of of_unittest_overlay_high_level is to add an overlay
+ * in the normal fashion.  This is a test of the whole picture,
+ * instead of individual elements.
+ *
+ * The first part of the function is _not_ normal overlay usage; it is
+ * finishing splicing the base overlay device tree into the live tree.
+ */
+static __init void of_unittest_overlay_high_level(void)
+{
+       struct device_node *last_sibling;
+       struct device_node *np;
+       struct device_node *of_symbols;
+       struct device_node *overlay_base_symbols;
+       struct device_node **pprev;
+       struct property *prop;
+       int ret;
+
+       if (!overlay_base_root) {
+               unittest(0, "overlay_base_root not initialized\n");
+               return;
+       }
+
+       /*
+        * Could not fixup phandles in unittest_unflatten_overlay_base()
+        * because kmalloc() was not yet available.
+        */
+       of_resolve_phandles(overlay_base_root);
+
+       /*
+        * do not allow overlay_base to duplicate any node already in
+        * tree, this greatly simplifies the code
+        */
+
+       /*
+        * remove overlay_base_root node "__local_fixups", after
+        * being used by of_resolve_phandles()
+        */
+       pprev = &overlay_base_root->child;
+       for (np = overlay_base_root->child; np; np = np->sibling) {
+               if (!of_node_cmp(np->name, "__local_fixups__")) {
+                       *pprev = np->sibling;
+                       break;
+               }
+               pprev = &np->sibling;
+       }
+
+       /* remove overlay_base_root node "__symbols__" if in live tree */
+       of_symbols = of_get_child_by_name(of_root, "__symbols__");
+       if (of_symbols) {
+               /* will have to graft properties from node into live tree */
+               pprev = &overlay_base_root->child;
+               for (np = overlay_base_root->child; np; np = np->sibling) {
+                       if (!of_node_cmp(np->name, "__symbols__")) {
+                               overlay_base_symbols = np;
+                               *pprev = np->sibling;
+                               break;
+                       }
+                       pprev = &np->sibling;
+               }
+       }
+
+       for (np = overlay_base_root->child; np; np = np->sibling) {
+               if (of_get_child_by_name(of_root, np->name)) {
+                       unittest(0, "illegal node name in overlay_base %s",
+                               np->name);
+                       return;
+               }
+       }
+
+       /*
+        * overlay 'overlay_base' is not allowed to have root
+        * properties, so only need to splice nodes into main device tree.
+        *
+        * root node of *overlay_base_root will not be freed, it is lost
+        * memory.
+        */
+
+       for (np = overlay_base_root->child; np; np = np->sibling)
+               np->parent = of_root;
+
+       mutex_lock(&of_mutex);
+
+       for (np = of_root->child; np; np = np->sibling)
+               last_sibling = np;
+
+       if (last_sibling)
+               last_sibling->sibling = overlay_base_root->child;
+       else
+               of_root->child = overlay_base_root->child;
+
+       for_each_of_allnodes_from(overlay_base_root, np)
+               __of_attach_node_sysfs(np);
+
+       if (of_symbols) {
+               for_each_property_of_node(overlay_base_symbols, prop) {
+                       ret = __of_add_property(of_symbols, prop);
+                       if (ret) {
+                               unittest(0,
+                                        "duplicate property '%s' in overlay_base node __symbols__",
+                                        prop->name);
+                               return;
+                       }
+                       ret = __of_add_property_sysfs(of_symbols, prop);
+                       if (ret) {
+                               unittest(0,
+                                        "unable to add property '%s' in overlay_base node __symbols__ to sysfs",
+                                        prop->name);
+                               return;
+                       }
+               }
+       }
+
+       mutex_unlock(&of_mutex);
+
+
+       /* now do the normal overlay usage test */
+
+       unittest(overlay_data_add(1),
+                "Adding overlay 'overlay' failed\n");
+
+       unittest(overlay_data_add(2),
+                "Adding overlay 'overlay_bad_phandle' failed\n");
+}
+
+#else
+
+static inline __init void of_unittest_overlay_high_level(void) {}
+
+#endif
+
 static int __init of_unittest(void)
 {
        struct device_node *np;
@@ -1962,6 +2277,8 @@ static int __init of_unittest(void)
        /* Double check linkage after removing testcase data */
        of_unittest_check_tree_linkage();
 
+       of_unittest_overlay_high_level();
+
        pr_info("end of unittest - %i passed, %i failed\n",
                unittest_results.passed, unittest_results.failed);