.. SPDX-License-Identifier: CC-BY-SA-4.0
IPU3 IPA Architecture Design and Overview
=========================================
The IPU3 IPA is built as a modular and extensible framework with an
upper layer to manage the interactions with the pipeline handler, and
the image processing algorithms split to compartmentalise the processing
required for each processing block, making use of the fixed-function
accelerators provided by the ImgU ISP.
The core IPU3 class is responsible for initialisation and construction
of the algorithm components, processing controls set by the requests
from applications, and managing events from the pipeline handler.
::
┌───────────────────────────────────────────┐
│ IPU3 Pipeline Handler │
│ ┌────────┐ ┌────────┐ ┌────────┐ │
│ │ │ │ │ │ │ │
│ │ Sensor ├───►│ CIO2 ├───►│ ImgU ├──►
│ │ │ │ │ │ │ │
│ └────────┘ └────────┘ └─▲────┬─┘ │ P: Parameter Buffer
│ │P │ │ S: Statistics Buffer
│ │ │S │
└─┬───┬───┬──────┬────┬────┬────┬─┴────▼─┬──┘ 1: init()
│ │ │ │ ▲ │ ▲ │ ▲ │ ▲ │ 2: configure()
│1 │2 │3 │4│ │4│ │4│ │4│ │5 3: mapBuffers(), start()
│ │ │ │ │ │ │ │ │ │ │ │ 4: (▼) queueRequest(), fillParamsBuffer(), processStatsBuffer()
▼ ▼ ▼ ▼ │ ▼ │ ▼ │ ▼ │ ▼ (▲) setSensorControls, paramsBufferReady, metadataReady Signals
┌──────────────────┴────┴────┴────┴─────────┐ 5: stop(), unmapBuffers()
│ IPU3 IPA │
│ ┌───────────────────────┐ │
│ ┌───────────┐ │ Algorithms │ │
│ │IPAContext │ │ ┌─────────┐ │ │
│ │ ┌───────┐ │ │ │ ... │ │ │
│ │ │ │ │ │ ┌─┴───────┐ │ │ │
│ │ │ SC │ │ │ │ Tonemap ├─┘ │ │
│ │ │ │ ◄───► ┌─┴───────┐ │ │ │
│ │ ├───────┤ │ │ │ AWB ├─┘ │ │
│ │ │ │ │ │ ┌─┴───────┐ │ │ │
│ │ │ FC │ │ │ │ AGC ├─┘ │ │
│ │ │ │ │ │ │ │ │ │
│ │ └───────┘ │ │ └─────────┘ │ │
│ └───────────┘ └───────────────────────┘ │
└───────────────────────────────────────────┘
SC: IPASessionConfiguration
FC: IPAFrameContext(s)
The IPA instance is constructed and initialised at the point a Camera is
created by the IPU3 pipeline handler. The initialisation call provides
details about which camera sensor is being used, and the controls that
it has available, along with their default values and ranges.
Buffers
~~~~~~~
The IPA will have Parameter and Statistics buffers shared with it from
the IPU3 Pipeline handler. These buffers will be passed to the IPA using
the ``mapBuffers()`` call before the ``start()`` operation occurs./* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
#ifndef _LINUX_UDMABUF_H
#define _LINUX_UDMABUF_H
#include <linux/types.h>
#include <linux/ioctl.h>
#define UDMABUF_FLAGS_CLOEXEC 0x01
struct udmabuf_create {
__u32 memfd;
__u32 flags;
__u64 offset;
__u64 size;
};
struct udmabuf_create_item {
__u32 memfd;
__u32 __pad;
__u64 offset;
__u64 size;
};
struct udmabuf_create_list {
__u32 flags;
__u32 count;
struct udmabuf_create_item list[];
};
#define UDMABUF_CREATE _IOW('u', 0x42, struct udmabuf_create)
#define UDMABUF_CREATE_LIST _IOW('u', 0x43, struct udmabuf_create_list)
#endif /* _LINUX_UDMABUF_H */