/* * Copyright (c) 2011 The Chromium OS Authors. * See file CREDITS for list of people who contributed to this * project. * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License as * published by the Free Software Foundation; either version 2 of * the License, or (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, * MA 02111-1307 USA */ #include <common.h> #include <serial.h> #include <libfdt.h> #include <fdtdec.h> /* we need the generic GPIO interface here */ #include <asm-generic/gpio.h> DECLARE_GLOBAL_DATA_PTR; /* * Here are the type we know about. One day we might allow drivers to * register. For now we just put them here. The COMPAT macro allows us to * turn this into a sparse list later, and keeps the ID with the name. */ #define COMPAT(id, name) name static const char * const compat_names[COMPAT_COUNT] = { COMPAT(UNKNOWN, "<none>"), COMPAT(NVIDIA_TEGRA20_USB, "nvidia,tegra20-ehci"), COMPAT(NVIDIA_TEGRA20_I2C, "nvidia,tegra20-i2c"), COMPAT(NVIDIA_TEGRA20_DVC, "nvidia,tegra20-i2c-dvc"), COMPAT(NVIDIA_TEGRA20_EMC, "nvidia,tegra20-emc"), COMPAT(NVIDIA_TEGRA20_EMC_TABLE, "nvidia,tegra20-emc-table"), COMPAT(NVIDIA_TEGRA20_KBC, "nvidia,tegra20-kbc"), }; const char *fdtdec_get_compatible(enum fdt_compat_id id) { /* We allow reading of the 'unknown' ID for testing purposes */ assert(id >= 0 && id < COMPAT_COUNT); return compat_names[id]; } /** * Look in the FDT for an alias with the given name and return its node. * * @param blob FDT blob * @param name alias name to look up * @return node offset if found, or an error code < 0 otherwise */ static int find_alias_node(const void *blob, const char *name) { const char *path; int alias_node; debug("find_alias_node: %s\n", name); alias_node = fdt_path_offset(blob, "/aliases"); if (alias_node < 0) return alias_node; path = fdt_getprop(blob, alias_node, name, NULL); if (!path) return -FDT_ERR_NOTFOUND; return fdt_path_offset(blob, path); } fdt_addr_t fdtdec_get_addr(const void *blob, int node, const char *prop_name) { const fdt_addr_t *cell; int len; debug("get_addr: %s\n", prop_name); cell = fdt_getprop(blob, node, prop_name, &len); if (cell && (len == sizeof(fdt_addr_t) || len == sizeof(fdt_addr_t) * 2)) return fdt_addr_to_cpu(*cell); return FDT_ADDR_T_NONE; } s32 fdtdec_get_int(const void *blob, int node, const char *prop_name, s32 default_val) { const s32 *cell; int len; debug("get_size: %s\n", prop_name); cell = fdt_getprop(blob, node, prop_name, &len); if (cell && len >= sizeof(s32)) return fdt32_to_cpu(cell[0]); return default_val; } int fdtdec_get_is_enabled(const void *blob, int node) { const char *cell; /* * It should say "okay", so only allow that. Some fdts use "ok" but * this is a bug. Please fix your device tree source file. See here * for discussion: * * http://www.mail-archive.com/u-boot@lists.denx.de/msg71598.html */ cell = fdt_getprop(blob, node, "status", NULL); if (cell) return 0 == strcmp(cell, "okay"); return 1; } enum fdt_compat_id fd_dec_lookup(const void *blob, int node) { enum fdt_compat_id id; /* Search our drivers */ for (id = COMPAT_UNKNOWN; id < COMPAT_COUNT; id++) if (0 == fdt_node_check_compatible(blob, node, compat_names[id])) return id; return COMPAT_UNKNOWN; } int fdtdec_next_compatible(const void *blob, int node, enum fdt_compat_id id) { return fdt_node_offset_by_compatible(blob, node, compat_names[id]); } int fdtdec_next_compatible_subnode(const void *blob, int node, enum fdt_compat_id id, int *depthp) { do { node = fdt_next_node(blob, node, depthp); } while (*depthp > 1); /* If this is a direct subnode, and compatible, return it */ if (*depthp == 1 && 0 == fdt_node_check_compatible( blob, node, compat_names[id])) return node; return -FDT_ERR_NOTFOUND; } int fdtdec_next_alias(const void *blob, const char *name, enum fdt_compat_id id, int *upto) { #define MAX_STR_LEN 20 char str[MAX_STR_LEN + 20]; int node, err; /* snprintf() is not available */ assert(strlen(name) < MAX_STR_LEN); sprintf(str, "%.*s%d", MAX_STR_LEN, name, *upto); node = find_alias_node(blob, str); if (node < 0) return node; err = fdt_node_check_compatible(blob, node, compat_names[id]); if (err < 0) return err; if (err) return -FDT_ERR_NOTFOUND; (*upto)++; return node; } int fdtdec_find_aliases_for_id(const void *blob, const char *name, enum fdt_compat_id id, int *node_list, int maxcount) { memset(node_list, '\0', sizeof(*node_list) * maxcount); return fdtdec_add_aliases_for_id(blob, name, id, node_list, maxcount); } /* TODO: Can we tighten this code up a little? */ int fdtdec_add_aliases_for_id(const void *blob, const char *name, enum fdt_compat_id id, int *node_list, int maxcount) { int name_len = strlen(name); int nodes[maxcount]; int num_found = 0; int offset, node; int alias_node; int count; int i, j; /* find the alias node if present */ alias_node = fdt_path_offset(blob, "/aliases"); /* * start with nothing, and we can assume that the root node can't * match */ memset(nodes, '\0', sizeof(nodes)); /* First find all the compatible nodes */ for (node = count = 0; node >= 0 && count < maxcount;) { node = fdtdec_next_compatible(blob, node, id); if (node >= 0) nodes[count++] = node; } if (node >= 0) debug("%s: warning: maxcount exceeded with alias '%s'\n", __func__, name); /* Now find all the aliases */ for (offset = fdt_first_property_offset(blob, alias_node); offset > 0; offset = fdt_next_property_offset(blob, offset)) { const struct fdt_property *prop; const char *path; int number; int found; node = 0; prop = fdt_get_property_by_offset(blob, offset, NULL); path = fdt_string(blob, fdt32_to_cpu(prop->nameoff)); if (prop->len && 0 == strncmp(path, name, name_len)) node = fdt_path_offset(blob, prop->data); if (node <= 0) continue; /* Get the alias number */ number = simple_strtoul(path + name_len, NULL, 10); if (number < 0 || number >= maxcount) { debug("%s: warning: alias '%s' is out of range\n", __func__, path); continue; } /* Make sure the node we found is actually in our list! */ found = -1; for (j = 0; j < count; j++) if (nodes[j] == node) { found = j; break; } if (found == -1) { debug("%s: warning: alias '%s' points to a node " "'%s' that is missing or is not compatible " " with '%s'\n", __func__, path, fdt_get_name(blob, node, NULL), compat_names[id]); continue; } /* * Add this node to our list in the right place, and mark * it as done. */ if (fdtdec_get_is_enabled(blob, node)) { if (node_list[number]) { debug("%s: warning: alias '%s' requires that " "a node be placed in the list in a " "position which is already filled by " "node '%s'\n", __func__, path, fdt_get_name(blob, node, NULL)); continue; } node_list[number] = node; if (number >= num_found) num_found = number + 1; } nodes[found] = 0; } /* Add any nodes not mentioned by an alias */ for (i = j = 0; i < maxcount; i++) { if (!node_list[i]) { for (; j < maxcount; j++) if (nodes[j] && fdtdec_get_is_enabled(blob, nodes[j])) break; /* Have we run out of nodes to add? */ if (j == maxcount) break; assert(!node_list[i]); node_list[i] = nodes[j++]; if (i >= num_found) num_found = i + 1; } } return num_found; } int fdtdec_check_fdt(void) { /* * We must have an FDT, but we cannot panic() yet since the console * is not ready. So for now, just assert(). Boards which need an early * FDT (prior to console ready) will need to make their own * arrangements and do their own checks. */ assert(!fdtdec_prepare_fdt()); return 0; } /* * This function is a little odd in that it accesses global data. At some * point if the architecture board.c files merge this will make more sense. * Even now, it is common code. */ int fdtdec_prepare_fdt(void) { if (((uintptr_t)gd->fdt_blob & 3) || fdt_check_header(gd->fdt_blob)) { printf("No valid FDT found - please append one to U-Boot " "binary, use u-boot-dtb.bin or define " "CONFIG_OF_EMBED\n"); return -1; } return 0; } int fdtdec_lookup_phandle(const void *blob, int node, const char *prop_name) { const u32 *phandle; int lookup; phandle = fdt_getprop(blob, node, prop_name, NULL); if (!phandle) return -FDT_ERR_NOTFOUND; lookup = fdt_node_offset_by_phandle(blob, fdt32_to_cpu(*phandle)); return lookup; } /** * Look up a property in a node and check that it has a minimum length. * * @param blob FDT blob * @param node node to examine * @param prop_name name of property to find * @param min_len minimum property length in bytes * @param err 0 if ok, or -FDT_ERR_NOTFOUND if the property is not found, or -FDT_ERR_BADLAYOUT if not enough data * @return pointer to cell, which is only valid if err == 0 */ static const void *get_prop_check_min_len(const void *blob, int node, const char *prop_name, int min_len, int *err) { const void *cell; int len; debug("%s: %s\n", __func__, prop_name); cell = fdt_getprop(blob, node, prop_name, &len); if (!cell) *err = -FDT_ERR_NOTFOUND; else if (len < min_len) *err = -FDT_ERR_BADLAYOUT; else *err = 0; return cell; } int fdtdec_get_int_array(const void *blob, int node, const char *prop_name, u32 *array, int count) { const u32 *cell; int i, err = 0; debug("%s: %s\n", __func__, prop_name); cell = get_prop_check_min_len(blob, node, prop_name, sizeof(u32) * count, &err); if (!err) { for (i = 0; i < count; i++) array[i] = fdt32_to_cpu(cell[i]); } return err; } const u32 *fdtdec_locate_array(const void *blob, int node, const char *prop_name, int count) { const u32 *cell; int err; cell = get_prop_check_min_len(blob, node, prop_name, sizeof(u32) * count, &err); return err ? NULL : cell; } int fdtdec_get_bool(const void *blob, int node, const char *prop_name) { const s32 *cell; int len; debug("%s: %s\n", __func__, prop_name); cell = fdt_getprop(blob, node, prop_name, &len); return cell != NULL; } /** * Decode a list of GPIOs from an FDT. This creates a list of GPIOs with no * terminating item. * * @param blob FDT blob to use * @param node Node to look at * @param prop_name Node property name * @param gpio Array of gpio elements to fill from FDT. This will be * untouched if either 0 or an error is returned * @param max_count Maximum number of elements allowed * @return number of GPIOs read if ok, -FDT_ERR_BADLAYOUT if max_count would * be exceeded, or -FDT_ERR_NOTFOUND if the property is missing. */ static int fdtdec_decode_gpios(const void *blob, int node, const char *prop_name, struct fdt_gpio_state *gpio, int max_count) { const struct fdt_property *prop; const u32 *cell; const char *name; int len, i; debug("%s: %s\n", __func__, prop_name); assert(max_count > 0); prop = fdt_get_property(blob, node, prop_name, &len); if (!prop) { debug("FDT: %s: property '%s' missing\n", __func__, prop_name); return -FDT_ERR_NOTFOUND; } /* We will use the name to tag the GPIO */ name = fdt_string(blob, fdt32_to_cpu(prop->nameoff)); cell = (u32 *)prop->data; len /= sizeof(u32) * 3; /* 3 cells per GPIO record */ if (len > max_count) { debug("FDT: %s: too many GPIOs / cells for " "property '%s'\n", __func__, prop_name); return -FDT_ERR_BADLAYOUT; } /* Read out the GPIO data from the cells */ for (i = 0; i < len; i++, cell += 3) { gpio[i].gpio = fdt32_to_cpu(cell[1]); gpio[i].flags = fdt32_to_cpu(cell[2]); gpio[i].name = name; } return len; } int fdtdec_decode_gpio(const void *blob, int node, const char *prop_name, struct fdt_gpio_state *gpio) { int err; debug("%s: %s\n", __func__, prop_name); gpio->gpio = FDT_GPIO_NONE; gpio->name = NULL; err = fdtdec_decode_gpios(blob, node, prop_name, gpio, 1); return err == 1 ? 0 : err; } int fdtdec_setup_gpio(struct fdt_gpio_state *gpio) { /* * Return success if there is no GPIO defined. This is used for * optional GPIOs) */ if (!fdt_gpio_isvalid(gpio)) return 0; if (gpio_request(gpio->gpio, gpio->name)) return -1; return 0; } int fdtdec_get_byte_array(const void *blob, int node, const char *prop_name, u8 *array, int count) { const u8 *cell; int err; cell = get_prop_check_min_len(blob, node, prop_name, count, &err); if (!err) memcpy(array, cell, count); return err; } const u8 *fdtdec_locate_byte_array(const void *blob, int node, const char *prop_name, int count) { const u8 *cell; int err; cell = get_prop_check_min_len(blob, node, prop_name, count, &err); if (err) return NULL; return cell; }