Four diagrams about the platform rather than the die. Each one is built from the same two words as every other page here — raised for a thing that exists, sunken for somewhere you cannot go or something that holds others — which is why none of them needs a legend.四张讲平台而不是讲裸片的图。每一张都只用这套页面一贯的两个词搭出来 —— 凸起是一个存在的东西，凹陷是去不了的地方、或者装着别人的容器 —— 所以它们都不需要图例。
Stages are grouped by which memory they execute from, and the group is the sunken band — so the diagram answers "where is this code actually running" without a separate column. The orange ring marks a stage that verifies the next one: that ring is the chain of trust, and the first stage without it is where the chain ends.阶段按在哪块内存里执行分组，组就是那条凹带 —— 这样图本身就回答了「这段代码到底跑在哪」，不用另开一列。橙色圈标的是会验下一级签名的阶段：那一圈就是信任链，第一个没有圈的地方就是链断掉的位置。
Same vocabulary as the memory map, different medium. What you must not move is drawn sunken — the bootloader partition is at a fixed offset because the mask ROM looks for it there, so resizing it does not fail at build time, it fails at power-on. The A/B pair is shown as a pair on purpose: touching one without the other is the mistake this diagram exists to prevent.和内存布局同一套说法，换了个介质。不能动的画成凹陷 —— bootloader 分区在固定偏移，因为掩膜 ROM 就去那个位置找它，所以改它的大小不会在编译时报错，会在上电时报错。A/B 两个成对画也是有意的：只改一个不改另一个，正是这张图要防的事。
One interrupt has two numbers, and confusing them costs an afternoon. The number in the SoC manual is the GIC input line; the number request_irq() wants is allocated at runtime and is not stable across boots. The groove between them is the translation, which is the whole point of the figure.一个中断有两个编号，搞混它们要花掉一个下午。芯片手册上的那个是 GIC 的输入线号；request_irq() 要的那个是运行时分配的，重启不保证一样。中间那道凹槽就是这次翻译，也是这张图存在的全部理由。
A pad has several possible functions and exactly one is connected — which is a segmented control, so it is drawn as one. The third row is outlined in the warning colour because two device-tree nodes both claim that pad: the kernel will not always refuse, and the symptom is a peripheral that works until the other driver probes.一个焊盘有好几种可能的功能，同时只有一路接得通 —— 这就是个分段控件，所以直接画成分段控件。第三行描了警示色，因为有两个设备树节点都声称占用这个焊盘：内核不一定会拒绝，症状是某个外设一直好用，直到另一个驱动 probe 起来。
Domains nest, and nesting is drawn as containment rather than as lines — a well inside a well is a domain inside a domain, so the reader never traces an edge to find out what goes off with what. The always-on domain carries the accent because it is the one that must still be alive to turn the others back on.域是嵌套的，而嵌套直接画成包含关系，不画线 —— 槽里套槽就是域里套域，读者不用顺着一条边去找「关谁会连带关掉谁」。常开域给强调色，因为它是那个必须还活着、才能把别的再打开的。