From dfbd4c6eff35f1b1065cca046003cc9d7ff27222 Mon Sep 17 00:00:00 2001 From: Gavin Shan Date: Tue, 3 May 2016 23:22:47 +1000 Subject: [PATCH] drivers/of: Split unflatten_dt_node() The function unflatten_dt_node() is called recursively to unflatten device nodes and properties in the FDT blob. It looks complicated and hard to be understood. This splits the function into 3 functions: populate_properties(), populate_node() and unflatten_dt_node(). populate_properties(), which is called by populate_node(), creates properties for the indicated device node. The later one creates the device nodes from FDT blob. populate_node() gets the offset in FDT blob for next device nodes and then calls populate_node(). No logical changes introduced. Signed-off-by: Gavin Shan Acked-by: Rob Herring Signed-off-by: Rob Herring --- drivers/of/fdt.c | 249 ++++++++++++++++++++++++++++------------------- 1 file changed, 147 insertions(+), 102 deletions(-) diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c index 5e897bfe6628..1b8c4ab0574d 100644 --- a/drivers/of/fdt.c +++ b/drivers/of/fdt.c @@ -161,39 +161,127 @@ static void *unflatten_dt_alloc(void **mem, unsigned long size, return res; } -/** - * unflatten_dt_node - Alloc and populate a device_node from the flat tree - * @blob: The parent device tree blob - * @mem: Memory chunk to use for allocating device nodes and properties - * @poffset: pointer to node in flat tree - * @dad: Parent struct device_node - * @nodepp: The device_node tree created by the call - * @fpsize: Size of the node path up at the current depth. - * @dryrun: If true, do not allocate device nodes but still calculate needed - * memory size - */ -static void * unflatten_dt_node(const void *blob, - void *mem, - int *poffset, - struct device_node *dad, - struct device_node **nodepp, - unsigned long fpsize, +static void populate_properties(const void *blob, + int offset, + void **mem, + struct device_node *np, + const char *nodename, bool dryrun) { - const __be32 *p; + struct property *pp, **pprev = NULL; + int cur; + bool has_name = false; + + pprev = &np->properties; + for (cur = fdt_first_property_offset(blob, offset); + cur >= 0; + cur = fdt_next_property_offset(blob, cur)) { + const __be32 *val; + const char *pname; + u32 sz; + + val = fdt_getprop_by_offset(blob, cur, &pname, &sz); + if (!val) { + pr_warn("%s: Cannot locate property at 0x%x\n", + __func__, cur); + continue; + } + + if (!pname) { + pr_warn("%s: Cannot find property name at 0x%x\n", + __func__, cur); + continue; + } + + if (!strcmp(pname, "name")) + has_name = true; + + pp = unflatten_dt_alloc(mem, sizeof(struct property), + __alignof__(struct property)); + if (dryrun) + continue; + + /* We accept flattened tree phandles either in + * ePAPR-style "phandle" properties, or the + * legacy "linux,phandle" properties. If both + * appear and have different values, things + * will get weird. Don't do that. + */ + if (!strcmp(pname, "phandle") || + !strcmp(pname, "linux,phandle")) { + if (!np->phandle) + np->phandle = be32_to_cpup(val); + } + + /* And we process the "ibm,phandle" property + * used in pSeries dynamic device tree + * stuff + */ + if (!strcmp(pname, "ibm,phandle")) + np->phandle = be32_to_cpup(val); + + pp->name = (char *)pname; + pp->length = sz; + pp->value = (__be32 *)val; + *pprev = pp; + pprev = &pp->next; + } + + /* With version 0x10 we may not have the name property, + * recreate it here from the unit name if absent + */ + if (!has_name) { + const char *p = nodename, *ps = p, *pa = NULL; + int len; + + while (*p) { + if ((*p) == '@') + pa = p; + else if ((*p) == '/') + ps = p + 1; + p++; + } + + if (pa < ps) + pa = p; + len = (pa - ps) + 1; + pp = unflatten_dt_alloc(mem, sizeof(struct property) + len, + __alignof__(struct property)); + if (!dryrun) { + pp->name = "name"; + pp->length = len; + pp->value = pp + 1; + *pprev = pp; + pprev = &pp->next; + memcpy(pp->value, ps, len - 1); + ((char *)pp->value)[len - 1] = 0; + pr_debug("fixed up name for %s -> %s\n", + nodename, (char *)pp->value); + } + } + + if (!dryrun) + *pprev = NULL; +} + +static unsigned long populate_node(const void *blob, + int offset, + void **mem, + struct device_node *dad, + unsigned long fpsize, + struct device_node **pnp, + bool dryrun) +{ struct device_node *np; - struct property *pp, **prev_pp = NULL; const char *pathp; unsigned int l, allocl; - static int depth; - int old_depth; - int offset; - int has_name = 0; int new_format = 0; - pathp = fdt_get_name(blob, *poffset, &l); - if (!pathp) - return mem; + pathp = fdt_get_name(blob, offset, &l); + if (!pathp) { + *pnp = NULL; + return 0; + } allocl = ++l; @@ -223,7 +311,7 @@ static void * unflatten_dt_node(const void *blob, } } - np = unflatten_dt_alloc(&mem, sizeof(struct device_node) + allocl, + np = unflatten_dt_alloc(mem, sizeof(struct device_node) + allocl, __alignof__(struct device_node)); if (!dryrun) { char *fn; @@ -246,89 +334,15 @@ static void * unflatten_dt_node(const void *blob, } memcpy(fn, pathp, l); - prev_pp = &np->properties; if (dad != NULL) { np->parent = dad; np->sibling = dad->child; dad->child = np; } } - /* process properties */ - for (offset = fdt_first_property_offset(blob, *poffset); - (offset >= 0); - (offset = fdt_next_property_offset(blob, offset))) { - const char *pname; - u32 sz; - if (!(p = fdt_getprop_by_offset(blob, offset, &pname, &sz))) { - offset = -FDT_ERR_INTERNAL; - break; - } - - if (pname == NULL) { - pr_info("Can't find property name in list !\n"); - break; - } - if (strcmp(pname, "name") == 0) - has_name = 1; - pp = unflatten_dt_alloc(&mem, sizeof(struct property), - __alignof__(struct property)); - if (!dryrun) { - /* We accept flattened tree phandles either in - * ePAPR-style "phandle" properties, or the - * legacy "linux,phandle" properties. If both - * appear and have different values, things - * will get weird. Don't do that. */ - if ((strcmp(pname, "phandle") == 0) || - (strcmp(pname, "linux,phandle") == 0)) { - if (np->phandle == 0) - np->phandle = be32_to_cpup(p); - } - /* And we process the "ibm,phandle" property - * used in pSeries dynamic device tree - * stuff */ - if (strcmp(pname, "ibm,phandle") == 0) - np->phandle = be32_to_cpup(p); - pp->name = (char *)pname; - pp->length = sz; - pp->value = (__be32 *)p; - *prev_pp = pp; - prev_pp = &pp->next; - } - } - /* with version 0x10 we may not have the name property, recreate - * it here from the unit name if absent - */ - if (!has_name) { - const char *p1 = pathp, *ps = pathp, *pa = NULL; - int sz; - - while (*p1) { - if ((*p1) == '@') - pa = p1; - if ((*p1) == '/') - ps = p1 + 1; - p1++; - } - if (pa < ps) - pa = p1; - sz = (pa - ps) + 1; - pp = unflatten_dt_alloc(&mem, sizeof(struct property) + sz, - __alignof__(struct property)); - if (!dryrun) { - pp->name = "name"; - pp->length = sz; - pp->value = pp + 1; - *prev_pp = pp; - prev_pp = &pp->next; - memcpy(pp->value, ps, sz - 1); - ((char *)pp->value)[sz - 1] = 0; - pr_debug("fixed up name for %s -> %s\n", pathp, - (char *)pp->value); - } - } + populate_properties(blob, offset, mem, np, pathp, dryrun); if (!dryrun) { - *prev_pp = NULL; np->name = of_get_property(np, "name", NULL); np->type = of_get_property(np, "device_type", NULL); @@ -338,6 +352,37 @@ static void * unflatten_dt_node(const void *blob, np->type = ""; } + *pnp = np; + return fpsize; +} + +/** + * unflatten_dt_node - Alloc and populate a device_node from the flat tree + * @blob: The parent device tree blob + * @mem: Memory chunk to use for allocating device nodes and properties + * @poffset: pointer to node in flat tree + * @dad: Parent struct device_node + * @nodepp: The device_node tree created by the call + * @fpsize: Size of the node path up at the current depth. + * @dryrun: If true, do not allocate device nodes but still calculate needed + * memory size + */ +static void *unflatten_dt_node(const void *blob, + void *mem, + int *poffset, + struct device_node *dad, + struct device_node **nodepp, + unsigned long fpsize, + bool dryrun) +{ + struct device_node *np; + static int depth; + int old_depth; + + fpsize = populate_node(blob, *poffset, &mem, dad, fpsize, &np, dryrun); + if (!fpsize) + return mem; + old_depth = depth; *poffset = fdt_next_node(blob, *poffset, &depth); if (depth < 0) -- 2.20.1