zephyr/soc/nordic/common/dmm.h

217 lines
7.2 KiB
C

/*
* Copyright (c) 2024 Nordic Semiconductor ASA
* SPDX-License-Identifier: Apache-2.0
*/
/**
* @file
* nRF SoC specific public APIs for Device Memory Management (dmm) subsystem
*/
#ifndef SOC_NORDIC_COMMON_DMM_H_
#define SOC_NORDIC_COMMON_DMM_H_
#include <stdint.h>
#include <zephyr/devicetree.h>
#include <zephyr/linker/devicetree_regions.h>
#include <zephyr/mem_mgmt/mem_attr.h>
#include <zephyr/sys/util.h>
#ifdef __cplusplus
extern "C" {
#endif
/** @cond INTERNAL_HIDDEN */
/* Determine if memory region is cacheable. */
#define DMM_IS_REG_CACHEABLE(node_id) \
COND_CODE_1(CONFIG_DCACHE, \
(COND_CODE_1(DT_NODE_HAS_PROP(node_id, zephyr_memory_attr), \
((DT_PROP(node_id, zephyr_memory_attr) & DT_MEM_CACHEABLE)), \
(0))), (0))
/* Determine required alignment of the data buffers in specified memory region.
* Cache line alignment is required if region is cacheable and data cache is enabled.
*/
#define DMM_REG_ALIGN_SIZE(node_id) \
(DMM_IS_REG_CACHEABLE(node_id) ? CONFIG_DCACHE_LINE_SIZE : sizeof(uint8_t))
/* Determine required alignment of the data buffers in memory region
* associated with specified device node.
*/
#define DMM_ALIGN_SIZE(node_id) DMM_REG_ALIGN_SIZE(DT_PHANDLE(node_id, memory_regions))
/**
* @brief Get reference to memory region associated with the specified device node
*
* @param node_id Device node.
*
* @return Reference to memory region. NULL if not defined for given device node.
*/
#define DMM_DEV_TO_REG(node_id) \
COND_CODE_1(DT_NODE_HAS_PROP(node_id, memory_regions), \
((void *)DT_REG_ADDR(DT_PHANDLE(node_id, memory_regions))), (NULL))
/**
* @brief Preallocate buffer in memory region associated with the specified device node
*
* @param node_id Device node.
*/
#define DMM_MEMORY_SECTION(node_id) \
COND_CODE_1(DT_NODE_HAS_PROP(node_id, memory_regions), \
(__attribute__((__section__(LINKER_DT_NODE_REGION_NAME( \
DT_PHANDLE(node_id, memory_regions))))) \
__aligned(DMM_ALIGN_SIZE(node_id))), \
())
#ifdef CONFIG_HAS_NORDIC_DMM
/**
* @brief Prepare a DMA output buffer for the specified device
*
* Allocate an output buffer in memory region that given device can perform DMA transfers from.
* Copy @p user_buffer contents into it.
* Writeback data cache lines associated with output buffer, if needed.
*
* @note Depending on provided user buffer parameters and SoC architecture,
* dynamic allocation and cache operations might be skipped.
*
* @note @p buffer_out can be released using @ref dmm_buffer_in_release()
* to support transmitting and receiving data to the same buffer.
*
* @warning It is prohibited to read or write @p user_buffer or @p buffer_out contents
* from the time this function is called until @ref dmm_buffer_out_release()
* or @ref dmm_buffer_in_release is called on the same buffer
* or until this function returns with an error.
*
* @param region Memory region associated with device to prepare the buffer for.
* @param user_buffer CPU address (virtual if applicable) of the buffer containing data
* to be processed by the given device.
* @param user_length Length of the buffer containing data to be processed by the given device.
* @param buffer_out Pointer to a bus address of a buffer containing the prepared DMA buffer.
*
* @retval 0 If succeeded.
* @retval -ENOMEM If output buffer could not be allocated.
* @retval -errno Negative errno for other failures.
*/
int dmm_buffer_out_prepare(void *region, void const *user_buffer, size_t user_length,
void **buffer_out);
/**
* @brief Release the previously prepared DMA output buffer
*
* @param region Memory region associated with device to release the buffer for.
* @param buffer_out Bus address of the DMA output buffer previously prepared
* with @ref dmm_buffer_out_prepare().
*
* @retval 0 If succeeded.
* @retval -errno Negative errno code on failure.
*/
int dmm_buffer_out_release(void *region, void *buffer_out);
/**
* @brief Prepare a DMA input buffer for the specified device
*
* Allocate an input buffer in memory region that given device can perform DMA transfers to.
*
* @note Depending on provided user buffer parameters and SoC architecture,
* dynamic allocation might be skipped.
*
* @warning It is prohibited to read or write @p user_buffer or @p buffer_in contents
* from the time this function is called until @ref dmm_buffer_in_release()
* is called on the same buffer or until this function returns with an error.
*
* @param region Memory region associated with device to prepare the buffer for.
* @param user_buffer CPU address (virtual if applicable) of the buffer to be filled with data
* from the given device.
* @param user_length Length of the buffer to be filled with data from the given device.
* @param buffer_in Pointer to a bus address of a buffer containing the prepared DMA buffer.
*
* @retval 0 If succeeded.
* @retval -ENOMEM If input buffer could not be allocated.
* @retval -errno Negative errno for other failures.
*/
int dmm_buffer_in_prepare(void *region, void *user_buffer, size_t user_length, void **buffer_in);
/**
* @brief Release the previously prepared DMA input buffer
*
* Invalidate data cache lines associated with input buffer, if needed.
* Copy @p buffer_in contents into @p user_buffer, if needed.
*
* @param region Memory region associated with device to release the buffer for.
* @param user_buffer CPU address (virtual if applicable) of the buffer to be filled with data
* from the given device.
* @param user_length Length of the buffer to be filled with data from the given device.
* @param buffer_in Bus address of the DMA input buffer previously prepared
* with @ref dmm_buffer_in_prepare().
*
* @note @p user_buffer and @p buffer_in arguments pair provided in this function call must match
* the arguments pair provided in prior call to @ref dmm_buffer_out_prepare()
* or @ref dmm_buffer_in_prepare().
*
* @retval 0 If succeeded.
* @retval -errno Negative errno code on failure.
*/
int dmm_buffer_in_release(void *region, void *user_buffer, size_t user_length, void *buffer_in);
/**
* @brief Initialize DMM.
*
* @retval 0 If succeeded.
* @retval -errno Negative errno code on failure.
*/
int dmm_init(void);
/** @endcond */
#else
static ALWAYS_INLINE int dmm_buffer_out_prepare(void *region, void const *user_buffer,
size_t user_length, void **buffer_out)
{
ARG_UNUSED(region);
ARG_UNUSED(user_length);
*buffer_out = (void *)user_buffer;
return 0;
}
static ALWAYS_INLINE int dmm_buffer_out_release(void *region, void *buffer_out)
{
ARG_UNUSED(region);
ARG_UNUSED(buffer_out);
return 0;
}
static ALWAYS_INLINE int dmm_buffer_in_prepare(void *region, void *user_buffer, size_t user_length,
void **buffer_in)
{
ARG_UNUSED(region);
ARG_UNUSED(user_length);
*buffer_in = user_buffer;
return 0;
}
static ALWAYS_INLINE int dmm_buffer_in_release(void *region, void *user_buffer, size_t user_length,
void *buffer_in)
{
ARG_UNUSED(region);
ARG_UNUSED(user_buffer);
ARG_UNUSED(user_length);
ARG_UNUSED(buffer_in);
return 0;
}
static ALWAYS_INLINE int dmm_init(void)
{
return 0;
}
#endif
#ifdef __cplusplus
}
#endif
#endif /* SOC_NORDIC_COMMON_DMM_H_ */