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Diffstat (limited to 'include/fdtdec.h')
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diff --git a/include/fdtdec.h b/include/fdtdec.h new file mode 100644 index 0000000..bdefda4 --- /dev/null +++ b/include/fdtdec.h @@ -0,0 +1,545 @@ +/* + * 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 + */ + +#ifndef __fdtdec_h +#define __fdtdec_h + +/* + * This file contains convenience functions for decoding useful and + * enlightening information from FDTs. It is intended to be used by device + * drivers and board-specific code within U-Boot. It aims to reduce the + * amount of FDT munging required within U-Boot itself, so that driver code + * changes to support FDT are minimized. + */ + +#include <libfdt.h> + +/* + * A typedef for a physical address. Note that fdt data is always big + * endian even on a litle endian machine. + */ +#ifdef CONFIG_PHYS_64BIT +typedef u64 fdt_addr_t; +typedef u64 fdt_size_t; +#define FDT_ADDR_T_NONE (-1ULL) +#define fdt_addr_to_cpu(reg) be64_to_cpu(reg) +#define fdt_size_to_cpu(reg) be64_to_cpu(reg) +#else +typedef u32 fdt_addr_t; +typedef u32 fdt_size_t; +#define FDT_ADDR_T_NONE (-1U) +#define fdt_addr_to_cpu(reg) be32_to_cpu(reg) +#define fdt_size_to_cpu(reg) be32_to_cpu(reg) +#endif + +/* Information obtained about memory from the FDT */ +struct fdt_memory { + fdt_addr_t start; + fdt_addr_t end; +}; + +/** + * Compat types that we know about and for which we might have drivers. + * Each is named COMPAT_<dir>_<filename> where <dir> is the directory + * within drivers. + */ +enum fdt_compat_id { + COMPAT_UNKNOWN, + COMPAT_NVIDIA_TEGRA20_USB, /* Tegra20 USB port */ + COMPAT_NVIDIA_TEGRA30_USB, /* Tegra30 USB port */ + COMPAT_NVIDIA_TEGRA114_USB, /* Tegra114 USB port */ + COMPAT_NVIDIA_TEGRA114_I2C, /* Tegra114 I2C w/single clock source */ + COMPAT_NVIDIA_TEGRA20_I2C, /* Tegra20 i2c */ + COMPAT_NVIDIA_TEGRA20_DVC, /* Tegra20 dvc (really just i2c) */ + COMPAT_NVIDIA_TEGRA20_EMC, /* Tegra20 memory controller */ + COMPAT_NVIDIA_TEGRA20_EMC_TABLE, /* Tegra20 memory timing table */ + COMPAT_NVIDIA_TEGRA20_KBC, /* Tegra20 Keyboard */ + COMPAT_NVIDIA_TEGRA20_NAND, /* Tegra2 NAND controller */ + COMPAT_NVIDIA_TEGRA20_PWM, /* Tegra 2 PWM controller */ + COMPAT_NVIDIA_TEGRA20_DC, /* Tegra 2 Display controller */ + COMPAT_NVIDIA_TEGRA30_SDMMC, /* Tegra30 SDMMC controller */ + COMPAT_NVIDIA_TEGRA20_SDMMC, /* Tegra20 SDMMC controller */ + COMPAT_NVIDIA_TEGRA20_SFLASH, /* Tegra 2 SPI flash controller */ + COMPAT_NVIDIA_TEGRA20_SLINK, /* Tegra 2 SPI SLINK controller */ + COMPAT_NVIDIA_TEGRA114_SPI, /* Tegra 114 SPI controller */ + COMPAT_SMSC_LAN9215, /* SMSC 10/100 Ethernet LAN9215 */ + COMPAT_SAMSUNG_EXYNOS5_SROMC, /* Exynos5 SROMC */ + COMPAT_SAMSUNG_S3C2440_I2C, /* Exynos I2C Controller */ + COMPAT_SAMSUNG_EXYNOS5_SOUND, /* Exynos Sound */ + COMPAT_WOLFSON_WM8994_CODEC, /* Wolfson WM8994 Sound Codec */ + COMPAT_SAMSUNG_EXYNOS_SPI, /* Exynos SPI */ + COMPAT_GOOGLE_CROS_EC, /* Google CROS_EC Protocol */ + COMPAT_GOOGLE_CROS_EC_KEYB, /* Google CROS_EC Keyboard */ + COMPAT_SAMSUNG_EXYNOS_EHCI, /* Exynos EHCI controller */ + COMPAT_SAMSUNG_EXYNOS_USB_PHY, /* Exynos phy controller for usb2.0 */ + COMPAT_SAMSUNG_EXYNOS_TMU, /* Exynos TMU */ + COMPAT_SAMSUNG_EXYNOS_FIMD, /* Exynos Display controller */ + COMPAT_SAMSUNG_EXYNOS5_DP, /* Exynos Display port controller */ + COMPAT_SAMSUNG_EXYNOS5_DWMMC, /* Exynos5 DWMMC controller */ + COMPAT_SAMSUNG_EXYNOS_SERIAL, /* Exynos UART */ + COMPAT_MAXIM_MAX77686_PMIC, /* MAX77686 PMIC */ + COMPAT_GENERIC_SPI_FLASH, /* Generic SPI Flash chip */ + COMPAT_MAXIM_98095_CODEC, /* MAX98095 Codec */ + COMPAT_INFINEON_SLB9635_TPM, /* Infineon SLB9635 TPM */ + COMPAT_INFINEON_SLB9645_TPM, /* Infineon SLB9645 TPM */ + + COMPAT_COUNT, +}; + +/* GPIOs are numbered from 0 */ +enum { + FDT_GPIO_NONE = -1U, /* an invalid GPIO used to end our list */ + + FDT_GPIO_ACTIVE_LOW = 1 << 0, /* input is active low (else high) */ +}; + +/* This is the state of a GPIO pin as defined by the fdt */ +struct fdt_gpio_state { + const char *name; /* name of the fdt property defining this */ + uint gpio; /* GPIO number, or FDT_GPIO_NONE if none */ + u8 flags; /* FDT_GPIO_... flags */ +}; + +/* This tells us whether a fdt_gpio_state record is valid or not */ +#define fdt_gpio_isvalid(x) ((x)->gpio != FDT_GPIO_NONE) + +/** + * Read the GPIO taking into account the polarity of the pin. + * + * @param gpio pointer to the decoded gpio + * @return value of the gpio if successful, < 0 if unsuccessful + */ +int fdtdec_get_gpio(struct fdt_gpio_state *gpio); + +/** + * Write the GPIO taking into account the polarity of the pin. + * + * @param gpio pointer to the decoded gpio + * @return 0 if successful + */ +int fdtdec_set_gpio(struct fdt_gpio_state *gpio, int val); + +/** + * Find the next numbered alias for a peripheral. This is used to enumerate + * all the peripherals of a certain type. + * + * Do the first call with *upto = 0. Assuming /aliases/<name>0 exists then + * this function will return a pointer to the node the alias points to, and + * then update *upto to 1. Next time you call this function, the next node + * will be returned. + * + * All nodes returned will match the compatible ID, as it is assumed that + * all peripherals use the same driver. + * + * @param blob FDT blob to use + * @param name Root name of alias to search for + * @param id Compatible ID to look for + * @return offset of next compatible node, or -FDT_ERR_NOTFOUND if no more + */ +int fdtdec_next_alias(const void *blob, const char *name, + enum fdt_compat_id id, int *upto); + +/** + * Find the compatible ID for a given node. + * + * Generally each node has at least one compatible string attached to it. + * This function looks through our list of known compatible strings and + * returns the corresponding ID which matches the compatible string. + * + * @param blob FDT blob to use + * @param node Node containing compatible string to find + * @return compatible ID, or COMPAT_UNKNOWN if we cannot find a match + */ +enum fdt_compat_id fdtdec_lookup(const void *blob, int node); + +/** + * Find the next compatible node for a peripheral. + * + * Do the first call with node = 0. This function will return a pointer to + * the next compatible node. Next time you call this function, pass the + * value returned, and the next node will be provided. + * + * @param blob FDT blob to use + * @param node Start node for search + * @param id Compatible ID to look for (enum fdt_compat_id) + * @return offset of next compatible node, or -FDT_ERR_NOTFOUND if no more + */ +int fdtdec_next_compatible(const void *blob, int node, + enum fdt_compat_id id); + +/** + * Find the next compatible subnode for a peripheral. + * + * Do the first call with node set to the parent and depth = 0. This + * function will return the offset of the next compatible node. Next time + * you call this function, pass the node value returned last time, with + * depth unchanged, and the next node will be provided. + * + * @param blob FDT blob to use + * @param node Start node for search + * @param id Compatible ID to look for (enum fdt_compat_id) + * @param depthp Current depth (set to 0 before first call) + * @return offset of next compatible node, or -FDT_ERR_NOTFOUND if no more + */ +int fdtdec_next_compatible_subnode(const void *blob, int node, + enum fdt_compat_id id, int *depthp); + +/** + * Look up an address property in a node and return it as an address. + * The property must hold either one address with no trailing data or + * one address with a length. This is only tested on 32-bit machines. + * + * @param blob FDT blob + * @param node node to examine + * @param prop_name name of property to find + * @return address, if found, or FDT_ADDR_T_NONE if not + */ +fdt_addr_t fdtdec_get_addr(const void *blob, int node, + const char *prop_name); + +/** + * Look up an address property in a node and return it as an address. + * The property must hold one address with a length. This is only tested + * on 32-bit machines. + * + * @param blob FDT blob + * @param node node to examine + * @param prop_name name of property to find + * @return address, if found, or FDT_ADDR_T_NONE if not + */ +fdt_addr_t fdtdec_get_addr_size(const void *blob, int node, + const char *prop_name, fdt_size_t *sizep); + +/** + * Look up a 32-bit integer property in a node and return it. The property + * must have at least 4 bytes of data. The value of the first cell is + * returned. + * + * @param blob FDT blob + * @param node node to examine + * @param prop_name name of property to find + * @param default_val default value to return if the property is not found + * @return integer value, if found, or default_val if not + */ +s32 fdtdec_get_int(const void *blob, int node, const char *prop_name, + s32 default_val); + +/** + * Look up a 64-bit integer property in a node and return it. The property + * must have at least 8 bytes of data (2 cells). The first two cells are + * concatenated to form a 8 bytes value, where the first cell is top half and + * the second cell is bottom half. + * + * @param blob FDT blob + * @param node node to examine + * @param prop_name name of property to find + * @param default_val default value to return if the property is not found + * @return integer value, if found, or default_val if not + */ +uint64_t fdtdec_get_uint64(const void *blob, int node, const char *prop_name, + uint64_t default_val); + +/** + * Checks whether a node is enabled. + * This looks for a 'status' property. If this exists, then returns 1 if + * the status is 'ok' and 0 otherwise. If there is no status property, + * it returns 1 on the assumption that anything mentioned should be enabled + * by default. + * + * @param blob FDT blob + * @param node node to examine + * @return integer value 0 (not enabled) or 1 (enabled) + */ +int fdtdec_get_is_enabled(const void *blob, int node); + +/** + * Make sure we have a valid fdt available to control U-Boot. + * + * If not, a message is printed to the console if the console is ready. + * + * @return 0 if all ok, -1 if not + */ +int fdtdec_prepare_fdt(void); + +/** + * Checks that we have a valid fdt available to control U-Boot. + + * However, if not then for the moment nothing is done, since this function + * is called too early to panic(). + * + * @returns 0 + */ +int fdtdec_check_fdt(void); + +/** + * Find the nodes for a peripheral and return a list of them in the correct + * order. This is used to enumerate all the peripherals of a certain type. + * + * To use this, optionally set up a /aliases node with alias properties for + * a peripheral. For example, for usb you could have: + * + * aliases { + * usb0 = "/ehci@c5008000"; + * usb1 = "/ehci@c5000000"; + * }; + * + * Pass "usb" as the name to this function and will return a list of two + * nodes offsets: /ehci@c5008000 and ehci@c5000000. + * + * All nodes returned will match the compatible ID, as it is assumed that + * all peripherals use the same driver. + * + * If no alias node is found, then the node list will be returned in the + * order found in the fdt. If the aliases mention a node which doesn't + * exist, then this will be ignored. If nodes are found with no aliases, + * they will be added in any order. + * + * If there is a gap in the aliases, then this function return a 0 node at + * that position. The return value will also count these gaps. + * + * This function checks node properties and will not return nodes which are + * marked disabled (status = "disabled"). + * + * @param blob FDT blob to use + * @param name Root name of alias to search for + * @param id Compatible ID to look for + * @param node_list Place to put list of found nodes + * @param maxcount Maximum number of nodes to find + * @return number of nodes found on success, FTD_ERR_... on error + */ +int fdtdec_find_aliases_for_id(const void *blob, const char *name, + enum fdt_compat_id id, int *node_list, int maxcount); + +/* + * This function is similar to fdtdec_find_aliases_for_id() except that it + * adds to the node_list that is passed in. Any 0 elements are considered + * available for allocation - others are considered already used and are + * skipped. + * + * You can use this by calling fdtdec_find_aliases_for_id() with an + * uninitialised array, then setting the elements that are returned to -1, + * say, then calling this function, perhaps with a different compat id. + * Any elements you get back that are >0 are new nodes added by the call + * to this function. + * + * Note that if you have some nodes with aliases and some without, you are + * sailing close to the wind. The call to fdtdec_find_aliases_for_id() with + * one compat_id may fill in positions for which you have aliases defined + * for another compat_id. When you later call *this* function with the second + * compat_id, the alias positions may already be used. A debug warning may + * be generated in this case, but it is safest to define aliases for all + * nodes when you care about the ordering. + */ +int fdtdec_add_aliases_for_id(const void *blob, const char *name, + enum fdt_compat_id id, int *node_list, int maxcount); + +/* + * Get the name for a compatible ID + * + * @param id Compatible ID to look for + * @return compatible string for that id + */ +const char *fdtdec_get_compatible(enum fdt_compat_id id); + +/* Look up a phandle and follow it to its node. Then return the offset + * of that node. + * + * @param blob FDT blob + * @param node node to examine + * @param prop_name name of property to find + * @return node offset if found, -ve error code on error + */ +int fdtdec_lookup_phandle(const void *blob, int node, const char *prop_name); + +/** + * Look up a property in a node and return its contents in an integer + * array of given length. The property must have at least enough data for + * the array (4*count bytes). It may have more, but this will be ignored. + * + * @param blob FDT blob + * @param node node to examine + * @param prop_name name of property to find + * @param array array to fill with data + * @param count number of array elements + * @return 0 if ok, or -FDT_ERR_NOTFOUND if the property is not found, + * or -FDT_ERR_BADLAYOUT if not enough data + */ +int fdtdec_get_int_array(const void *blob, int node, const char *prop_name, + u32 *array, int count); + +/** + * Look up a property in a node and return a pointer to its contents as a + * unsigned int array of given length. The property must have at least enough + * data for the array ('count' cells). It may have more, but this will be + * ignored. The data is not copied. + * + * Note that you must access elements of the array with fdt32_to_cpu(), + * since the elements will be big endian even on a little endian machine. + * + * @param blob FDT blob + * @param node node to examine + * @param prop_name name of property to find + * @param count number of array elements + * @return pointer to array if found, or NULL if the property is not + * found or there is not enough data + */ +const u32 *fdtdec_locate_array(const void *blob, int node, + const char *prop_name, int count); + +/** + * Look up a boolean property in a node and return it. + * + * A boolean properly is true if present in the device tree and false if not + * present, regardless of its value. + * + * @param blob FDT blob + * @param node node to examine + * @param prop_name name of property to find + * @return 1 if the properly is present; 0 if it isn't present + */ +int fdtdec_get_bool(const void *blob, int node, const char *prop_name); + +/** + * Decode a single GPIOs from an FDT. + * + * If the property is not found, then the GPIO structure will still be + * initialised, with gpio set to FDT_GPIO_NONE. This makes it easy to + * provide optional GPIOs. + * + * @param blob FDT blob to use + * @param node Node to look at + * @param prop_name Node property name + * @param gpio gpio elements to fill from FDT + * @return 0 if ok, -FDT_ERR_NOTFOUND if the property is missing. + */ +int fdtdec_decode_gpio(const void *blob, int node, const char *prop_name, + struct fdt_gpio_state *gpio); + +/** + * 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. + */ +int fdtdec_decode_gpios(const void *blob, int node, const char *prop_name, + struct fdt_gpio_state *gpio, int max_count); + +/** + * Set up a GPIO pin according to the provided gpio information. At present this + * just requests the GPIO. + * + * If the gpio is FDT_GPIO_NONE, no action is taken. This makes it easy to + * deal with optional GPIOs. + * + * @param gpio GPIO info to use for set up + * @return 0 if all ok or gpio was FDT_GPIO_NONE; -1 on error + */ +int fdtdec_setup_gpio(struct fdt_gpio_state *gpio); + +/** + * Look in the FDT for a config item with the given name and return its value + * as a 32-bit integer. The property must have at least 4 bytes of data. The + * value of the first cell is returned. + * + * @param blob FDT blob to use + * @param prop_name Node property name + * @param default_val default value to return if the property is not found + * @return integer value, if found, or default_val if not + */ +int fdtdec_get_config_int(const void *blob, const char *prop_name, + int default_val); + +/** + * Look in the FDT for a config item with the given name + * and return whether it exists. + * + * @param blob FDT blob + * @param prop_name property name to look up + * @return 1, if it exists, or 0 if not + */ +int fdtdec_get_config_bool(const void *blob, const char *prop_name); + +/** + * Look in the FDT for a config item with the given name and return its value + * as a string. + * + * @param blob FDT blob + * @param prop_name property name to look up + * @returns property string, NULL on error. + */ +char *fdtdec_get_config_string(const void *blob, const char *prop_name); + +/* + * Look up a property in a node and return its contents in a byte + * array of given length. The property must have at least enough data for + * the array (count bytes). It may have more, but this will be ignored. + * + * @param blob FDT blob + * @param node node to examine + * @param prop_name name of property to find + * @param array array to fill with data + * @param count number of array elements + * @return 0 if ok, or -FDT_ERR_MISSING if the property is not found, + * or -FDT_ERR_BADLAYOUT if not enough data + */ +int fdtdec_get_byte_array(const void *blob, int node, const char *prop_name, + u8 *array, int count); + +/** + * Look up a property in a node and return a pointer to its contents as a + * byte array of given length. The property must have at least enough data + * for the array (count bytes). It may have more, but this will be ignored. + * The data is not copied. + * + * @param blob FDT blob + * @param node node to examine + * @param prop_name name of property to find + * @param count number of array elements + * @return pointer to byte array if found, or NULL if the property is not + * found or there is not enough data + */ +const u8 *fdtdec_locate_byte_array(const void *blob, int node, + const char *prop_name, int count); + +/** + * Look up a property in a node which contains a memory region address and + * size. Then return a pointer to this address. + * + * The property must hold one address with a length. This is only tested on + * 32-bit machines. + * + * @param blob FDT blob + * @param node node to examine + * @param prop_name name of property to find + * @param ptrp returns pointer to region, or NULL if no address + * @param size returns size of region + * @return 0 if ok, -1 on error (propery not found) + */ +int fdtdec_decode_region(const void *blob, int node, + const char *prop_name, void **ptrp, size_t *size); +#endif |
