diff options
Diffstat (limited to 'lib/fdtdec.c')
-rw-r--r-- | lib/fdtdec.c | 323 |
1 files changed, 313 insertions, 10 deletions
diff --git a/lib/fdtdec.c b/lib/fdtdec.c index 0f87163..bdec1a0 100644 --- a/lib/fdtdec.c +++ b/lib/fdtdec.c @@ -24,6 +24,9 @@ #include <libfdt.h> #include <fdtdec.h> +/* we need the generic GPIO interface here */ +#include <asm-generic/gpio.h> + DECLARE_GLOBAL_DATA_PTR; /* @@ -33,8 +36,19 @@ DECLARE_GLOBAL_DATA_PTR; */ #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"), }; +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. * @@ -84,14 +98,21 @@ s32 fdtdec_get_int(const void *blob, int node, const char *prop_name, return default_val; } -int fdtdec_get_is_enabled(const void *blob, int node, int 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, "ok"); - return default_val; + return 0 == strcmp(cell, "okay"); + return 1; } enum fdt_compat_id fd_dec_lookup(const void *blob, int node) @@ -122,14 +143,151 @@ int fdtdec_next_alias(const void *blob, const char *name, /* snprintf() is not available */ assert(strlen(name) < MAX_STR_LEN); sprintf(str, "%.*s%d", MAX_STR_LEN, name, *upto); - (*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; - return err ? -FDT_ERR_NOTFOUND : node; + 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; } /* @@ -137,11 +295,156 @@ int fdtdec_next_alias(const void *blob, const char *name, * point if the architecture board.c files merge this will make more sense. * Even now, it is common code. */ -int fdtdec_check_fdt(void) +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) { - /* We must have an fdt */ - if (fdt_check_header(gd->fdt_blob)) - panic("No valid fdt found - please append one to U-Boot\n" - "binary or define CONFIG_OF_EMBED\n"); + 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; +} + +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; } |