diff options
Diffstat (limited to 'drivers/of/unittest.c')
| -rw-r--r-- | drivers/of/unittest.c | 317 |
1 files changed, 317 insertions, 0 deletions
diff --git a/drivers/of/unittest.c b/drivers/of/unittest.c index 62db55b97c10..12597ff8cfb0 100644 --- a/drivers/of/unittest.c +++ b/drivers/of/unittest.c @@ -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); |