OVMS3-idf/components/esp32/include/esp_spiram.h
Ivan Grokhotkov 1da3204a7c spiram: expose function to initialize SPI RAM cache
Some frameworks based on ESP-IDF need to be able to decide whether to
initialize SPI RAM after the application has started. This change splits
out part of esp_spiram_init which manipulate cache MMU into a separate
function. Applications can disable cache, call esp_spiram_init_cache,
re-enable cache, and then call esp_spiram_init.
Disabling and re-enabling the cache can be achieved using functions
provided in esp_spi_flash.h.
2017-10-16 09:15:11 +08:00

90 lines
2.5 KiB
C

// Copyright 2015-2017 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.
#ifndef __ESP_SPIRAM_H
#define __ESP_SPIRAM_H
#include <stddef.h>
#include <stdint.h>
#include "esp_err.h"
/**
* @brief Initialize spiram interface/hardware. Normally called from cpu_start.c.
*
* @return ESP_OK on success
*/
esp_err_t esp_spiram_init();
/**
* @brief Configure Cache/MMU for access to external SPI RAM.
*
* Normally this function is called from cpu_start, if CONFIG_SPIRAM_BOOT_INIT
* option is enabled. Applications which need to enable SPI RAM at run time
* can disable CONFIG_SPIRAM_BOOT_INIT, and call this function later.
*
* @attention this function must be called with flash cache disabled.
*/
void esp_spiram_init_cache();
/**
* @brief Memory test for SPI RAM. Should be called after SPI RAM is initialized and
* (in case of a dual-core system) the app CPU is online. This test overwrites the
* memory with crap, so do not call after e.g. the heap allocator has stored important
* stuff in SPI RAM.
*
* @return true on success, false on failed memory test
*/
bool esp_spiram_test();
/**
* @brief Add the initialized SPI RAM to the heap allocator.
*/
esp_err_t esp_spiram_add_to_heapalloc();
/**
* @brief Get the size of the attached SPI RAM chip selected in menuconfig
*
* @return Size in bytes, or 0 if no external RAM chip support compiled in.
*/
size_t esp_spiram_get_size();
/**
* @brief Force a writeback of the data in the SPI RAM cache. This is to be called whenever
* cache is disabled, because disabling cache on the ESP32 discards the data in the SPI
* RAM cache.
*
* This is meant for use from within the SPI flash code.
*/
void esp_spiram_writeback_cache();
/**
* @brief Reserve a pool of internal memory for specific DMA/internal allocations
*
* @param size Size of reserved pool in bytes
*
* @return
* - ESP_OK on success
* - ESP_ERR_NO_MEM when no memory available for pool
*/
esp_err_t esp_spiram_reserve_dma_pool(size_t size);
#endif