esp-idf/components/ulp/include/ulp_common.h

// Copyright 2016-2018 Espressif Systems (Shanghai) PTE LTD
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#pragma once

/* This file contains definitions that are common between esp32/ulp.h
   and esp32s2/ulp.h
*/

#ifdef __cplusplus
extern "C" {
#endif

/**@{*/
#define ESP_ERR_ULP_BASE                0x1200                  /*!< Offset for ULP-related error codes */
#define ESP_ERR_ULP_SIZE_TOO_BIG        (ESP_ERR_ULP_BASE + 1)  /*!< Program doesn't fit into RTC memory reserved for the ULP */
#define ESP_ERR_ULP_INVALID_LOAD_ADDR   (ESP_ERR_ULP_BASE + 2)  /*!< Load address is outside of RTC memory reserved for the ULP */
#define ESP_ERR_ULP_DUPLICATE_LABEL     (ESP_ERR_ULP_BASE + 3)  /*!< More than one label with the same number was defined */
#define ESP_ERR_ULP_UNDEFINED_LABEL     (ESP_ERR_ULP_BASE + 4)  /*!< Branch instructions references an undefined label */
#define ESP_ERR_ULP_BRANCH_OUT_OF_RANGE (ESP_ERR_ULP_BASE + 5)  /*!< Branch target is out of range of B instruction (try replacing with BX) */
/**@}*/

union ulp_insn;  // Declared in the chip-specific ulp.h header

typedef union ulp_insn ulp_insn_t;

/**
 * @brief Resolve all macro references in a program and load it into RTC memory
 * @param load_addr  address where the program should be loaded, expressed in 32-bit words
 * @param program  ulp_insn_t array with the program
 * @param psize  size of the program, expressed in 32-bit words
 * @return
 *      - ESP_OK on success
 *      - ESP_ERR_NO_MEM if auxiliary temporary structure can not be allocated
 *      - one of ESP_ERR_ULP_xxx if program is not valid or can not be loaded
 */
esp_err_t ulp_process_macros_and_load(uint32_t load_addr, const ulp_insn_t* program, size_t* psize);

/**
 * @brief Load ULP program binary into RTC memory
 *
 * ULP program binary should have the following format (all values little-endian):
 *
 * 1. MAGIC, (value 0x00706c75, 4 bytes)
 * 2. TEXT_OFFSET, offset of .text section from binary start (2 bytes)
 * 3. TEXT_SIZE, size of .text section (2 bytes)
 * 4. DATA_SIZE, size of .data section (2 bytes)
 * 5. BSS_SIZE, size of .bss section (2 bytes)
 * 6. (TEXT_OFFSET - 12) bytes of arbitrary data (will not be loaded into RTC memory)
 * 7. .text section
 * 8. .data section
 *
 * Linker script in components/ulp/ld/esp32.ulp.ld produces ELF files which
 * correspond to this format. This linker script produces binaries with load_addr == 0.
 *
 * @param load_addr address where the program should be loaded, expressed in 32-bit words
 * @param program_binary pointer to program binary
 * @param program_size size of the program binary
 * @return
 *      - ESP_OK on success
 *      - ESP_ERR_INVALID_ARG if load_addr is out of range
 *      - ESP_ERR_INVALID_SIZE if program_size doesn't match (TEXT_OFFSET + TEXT_SIZE + DATA_SIZE)
 *      - ESP_ERR_NOT_SUPPORTED if the magic number is incorrect
 */
esp_err_t ulp_load_binary(uint32_t load_addr, const uint8_t* program_binary, size_t program_size);

/**
 * @brief Run the program loaded into RTC memory
 * @param entry_point entry point, expressed in 32-bit words
 * @return  ESP_OK on success
 */
esp_err_t ulp_run(uint32_t entry_point);

/**
 * @brief Set one of ULP wakeup period values
 *
 * ULP coprocessor starts running the program when the wakeup timer counts up
 * to a given value (called period). There are 5 period values which can be
 * programmed into SENS_ULP_CP_SLEEP_CYCx_REG registers, x = 0..4.
 * By default, wakeup timer will use the period set into SENS_ULP_CP_SLEEP_CYC0_REG,
 * i.e. period number 0. ULP program code can use SLEEP instruction to select
 * which of the SENS_ULP_CP_SLEEP_CYCx_REG should be used for subsequent wakeups.
 *
 * However, please note that SLEEP instruction issued (from ULP program) while the system
 * is in deep sleep mode does not have effect, and sleep cycle count 0 is used.
 *
 * @param period_index wakeup period setting number (0 - 4)
 * @param period_us wakeup period, us
 * @note  The ULP FSM requires two clock cycles to wakeup before being able to run the program.
 *        Then additional 16 cycles are reserved after wakeup waiting until the 8M clock is stable.
 *        The FSM also requires two more clock cycles to go to sleep after the program execution is halted.
 *        The minimum wakeup period that may be set up for the ULP
 *        is equal to the total number of cycles spent on the above internal tasks.
 *        For a default configuration of the ULP running at 150kHz it makes about 133us.
 * @return
 *      - ESP_OK on success
 *      - ESP_ERR_INVALID_ARG if period_index is out of range
 */
esp_err_t ulp_set_wakeup_period(size_t period_index, uint32_t period_us);

#ifdef __cplusplus
}
#endif