From abaa8f5782df7b8cfe4e3171b168d373bd680fa8 Mon Sep 17 00:00:00 2001 From: Chen Guokai Date: Tue, 21 Apr 2020 09:50:50 +0800 Subject: [PATCH] Add cleanroom document --rebased --- flashloaders/cleanroom.md | 232 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 232 insertions(+) create mode 100644 flashloaders/cleanroom.md diff --git a/flashloaders/cleanroom.md b/flashloaders/cleanroom.md new file mode 100644 index 0000000..594e719 --- /dev/null +++ b/flashloaders/cleanroom.md @@ -0,0 +1,232 @@ +English version can be found below. + +# 净室工程文档 + +代码位于的section：`.text` +编译制导添加`.syntax unified` + +传入参数约定： + +参数全部通过寄存器传递 + +`r0`: 拷贝源点起始地址 +`r1`: 拷贝终点起始地址 +`r2`: 拷贝word（4字节）数(存在例外) + +程序功能：将数据从源点拷贝到终点，在拷贝完毕后触发断点以结束执行，结束时`r2`值需清零表明传输完毕。 + +限制：不可使用栈，可自由使用的临时寄存器为`R3`到`R12`。`R13`为`sp`（stack pointer），`R14`为lr（一般用于储存跳转地址），`R15`为`pc`（program counter）。 + +要求：每完成一次拷贝，需等待flash完成写入，单次拷贝宽度、检查写入完成的方式见每个文件的具体要求。 + +特殊地址`flash_base`存放地址需2字节对齐。 + +## stm32f0.s + +例外：`r2`:拷贝half word（2字节）数 + +特殊地址定义：`flash_base`:定义为0x40022000 + +`FLASH_CR`: 相对`flash_base`的offset为16 + +`FLASH_SR`: 相对`flash_base`的offset为12 + +参考：[https://chromium.googlesource.com/chromiumos/platform/ec/+/master/chip/stm32/registers-stm32f0.h](https://chromium.googlesource.com/chromiumos/platform/ec/+/master/chip/stm32/registers-stm32f0.h) +[https://www.st.com/resource/en/reference_manual/dm00031936-stm32f0x1stm32f0x2stm32f0x8-advanced-armbased-32bit-mcus-stmicroelectronics.pdf](https://www.st.com/resource/en/reference_manual/dm00031936-stm32f0x1stm32f0x2stm32f0x8-advanced-armbased-32bit-mcus-stmicroelectronics.pdf) + +特殊要求： +每次拷贝开始前需要读出FLASH_CR处的4字节内容，将其最低bit设置为1，写回FLASH_CR。 + +每次写入数据宽度为2字节（半字）。 + +每完成一次写入，需等待flash完成写入，检查方式为读取FLASH_SR处4字节内容，若取值为1，则说明写入尚未完成，需继续轮询等待；否则需要检查FLASH_SR处值是否为4，若是4，则应直接准备退出。 + +退出：全部拷贝执行完毕后触发断点前，将FLASH_CR处4字节内容最低bit清为0，写回FLASH_CR。 + + + +## stm32f4.s + +特殊地址定义： `flash_base`：定义为0x40023c00 + +`FLASH_SR`:相对flash_base的offset为0xe（14） + +参考：[https://chromium.googlesource.com/chromiumos/platform/ec/+/master/chip/stm32/registers-stm32f4.h](https://chromium.googlesource.com/chromiumos/platform/ec/+/master/chip/stm32/registers-stm32f4.h) +[https://www.st.com/content/ccc/resource/technical/document/reference_manual/3d/6d/5a/66/b4/99/40/d4/DM00031020.pdf/files/DM00031020.pdf/jcr:content/translations/en.DM00031020.pdf](https://www.st.com/content/ccc/resource/technical/document/reference_manual/3d/6d/5a/66/b4/99/40/d4/DM00031020.pdf/files/DM00031020.pdf/jcr:content/translations/en.DM00031020.pdf) + +特殊要求： + +每次写入的数据宽度为4字节（字）。 + +每完成一次写入，需等待flash完成写入，检查方式为读取FLASH_SR处2字节内容，若取值为1，则说明写入尚未完成，需继续轮询等待。 + +## stm32f4lv.s + +特殊地址定义：`flash_base`：定义为0x40023c00 + +`FLASH_SR`:相对`flash_base`的offset为0xe (14) + +参考：[https://chromium.googlesource.com/chromiumos/platform/ec/+/master/chip/stm32/registers-stm32f4.h](https://chromium.googlesource.com/chromiumos/platform/ec/+/master/chip/stm32/registers-stm32f4.h) +[https://www.st.com/content/ccc/resource/technical/document/reference_manual/3d/6d/5a/66/b4/99/40/d4/DM00031020.pdf/files/DM00031020.pdf/jcr:content/translations/en.DM00031020.pdf](https://www.st.com/content/ccc/resource/technical/document/reference_manual/3d/6d/5a/66/b4/99/40/d4/DM00031020.pdf/files/DM00031020.pdf/jcr:content/translations/en.DM00031020.pdf) + +特殊要求： + +每次写入的数据宽度为1字节（1/4字）。 + +每完成一次写入，需等待flash完成写入，检查方式为读取FLASH_SR处2字节内容，若取值为1，则说明写入尚未完成，需继续轮询等待。 + +## stm32f7.s + +参考：[https://chromium.googlesource.com/chromiumos/platform/ec/+/master/chip/stm32/registers-stm32f7.h](https://chromium.googlesource.com/chromiumos/platform/ec/+/master/chip/stm32/registers-stm32f7.h) +[https://www.st.com/resource/en/reference_manual/dm00124865-stm32f75xxx-and-stm32f74xxx-advanced-armbased-32bit-mcus-stmicroelectronics.pdf](https://www.st.com/resource/en/reference_manual/dm00124865-stm32f75xxx-and-stm32f74xxx-advanced-armbased-32bit-mcus-stmicroelectronics.pdf) + +要求同stm32f4.s，额外要求在每次拷贝执行完毕、flash写入成功检测前，执行`dsb sy`指令以建立内存屏障。 + + +## stm32f7lv.s + +参考：[https://chromium.googlesource.com/chromiumos/platform/ec/+/master/chip/stm32/registers-stm32f7.h](https://chromium.googlesource.com/chromiumos/platform/ec/+/master/chip/stm32/registers-stm32f7.h) +[https://www.st.com/resource/en/reference_manual/dm00124865-stm32f75xxx-and-stm32f74xxx-advanced-armbased-32bit-mcus-stmicroelectronics.pdf](https://www.st.com/resource/en/reference_manual/dm00124865-stm32f75xxx-and-stm32f74xxx-advanced-armbased-32bit-mcus-stmicroelectronics.pdf) +要求基本同stm32f7.s，差异要求为每次写入的数据宽度为1字节（1/4字）。 + +## stm32l0x.s + +特殊要求： + +每次写入的数据宽度为4字节（字） + +无需实现检查flash写入完成功能 + +## stm32l4.s + +例外：`r2`： 拷贝双字（8字节）数 + +特殊地址定义：`flash_base`: 0x40022000 + +`FLASH_BSY`：相对flash_base的offset为0x12 + +参考：[https://chromium.googlesource.com/chromiumos/platform/ec/+/master/chip/stm32/registers-stm32l4.h](https://chromium.googlesource.com/chromiumos/platform/ec/+/master/chip/stm32/registers-stm32l4.h) +[https://www.st.com/resource/en/reference_manual/dm00310109-stm32l4-series-advanced-armbased-32bit-mcus-stmicroelectronics.pdf](https://www.st.com/resource/en/reference_manual/dm00310109-stm32l4-series-advanced-armbased-32bit-mcus-stmicroelectronics.pdf) + +拷贝方式：一次性拷贝连续的8个字节（使用两个连续寄存器作中转）并写入 + +每完成一次写入，需等待flash完成写入，检查方式为读取FLASH_BSY处半字（2字节），若其最低位非1，可继续拷贝。 + +## stm32lx.s + +要求与stm32l0x.s相同 + +# Clean Room Documentation English Version + +Code is situated in section `.text` + +Shall add a compile directive at the head: `.syntax unified` + +**Calling convention**: + +All parameters would be passed over registers + +`r0`: the base address of the copy source +`r1`: the base address of the copy destination +`r2`: the total word (4 bytes) count to be copied (with expeptions) + +**What the program is expected to do**: + +Copy data from source to destination, after which trigger a breakpint to exit. Before exit, `r2` must be cleared to zero to indicate that the copy is done. + +**Limitation**: No stack operations are permitted. Registers ranging from `r3` to `r12` are free to use. Note that `r13` is `sp`(stack pointer), `r14` is `lr`(commonly used to store jump address), `r15` is `pc`(program counter). + +**Requirement**: After every single copy, wait until the flash finishes. The detailed single copy length and the way to check can be found below. Address of `flash_base` shall be two-bytes aligned. + +## stm32f0.s + +**Exception**: `r2` stores the total half word (2 bytes) count to be copied + +`flash_base`: 0x40022000 + +`FLASH_CR`: offset from `flash_base` is 16 + +`FLASH_SR`: offset from `flash_base` is 12 + +**Reference**: [https://chromium.googlesource.com/chromiumos/platform/ec/+/master/chip/stm32/registers-stm32f0.h](https://chromium.googlesource.com/chromiumos/platform/ec/+/master/chip/stm32/registers-stm32f0.h) +[https://www.st.com/resource/en/reference_manual/dm00031936-stm32f0x1stm32f0x2stm32f0x8-advanced-armbased-32bit-mcus-stmicroelectronics.pdf](https://www.st.com/resource/en/reference_manual/dm00031936-stm32f0x1stm32f0x2stm32f0x8-advanced-armbased-32bit-mcus-stmicroelectronics.pdf) + +**Special requirements**: + +Before every copy, read a word from FLASH_CR, set the lowest bit to 1 and write back. Copy one half word each time. + +How to wait for the write process: read a word from FLASH_SR, loop until the content is not 1. After that, check FLASH_SR, proceed if the content is not 4, otherwise exit. + +Exit: after the copying process and before triggering the breakpoint, clear the lowest bit in FLASH_CR. + +## stm32f4.s + +`flash_base`: 0x40023c00 + +`FLASH_SR`: offset from `flash_base` is 0xe (14) + +**Reference**: [https://chromium.googlesource.com/chromiumos/platform/ec/+/master/chip/stm32/registers-stm32f4.h](https://chromium.googlesource.com/chromiumos/platform/ec/+/master/chip/stm32/registers-stm32f4.h) +[https://www.st.com/content/ccc/resource/technical/document/reference_manual/3d/6d/5a/66/b4/99/40/d4/DM00031020.pdf/files/DM00031020.pdf/jcr:content/translations/en.DM00031020.pdf](https://www.st.com/content/ccc/resource/technical/document/reference_manual/3d/6d/5a/66/b4/99/40/d4/DM00031020.pdf/files/DM00031020.pdf/jcr:content/translations/en.DM00031020.pdf) + + +**Special requirements**: + +Copy one word each time. +How to wait for the write process: read a half word from FLASH_SR, loop until the content is not 1. + +## stm32f4lv.s + +`flash_base`: 0x40023c00 + +`FLASH_SR`: offset from `flash_base` is 0xe (14) + +**Reference**: [https://chromium.googlesource.com/chromiumos/platform/ec/+/master/chip/stm32/registers-stm32f4.h](https://chromium.googlesource.com/chromiumos/platform/ec/+/master/chip/stm32/registers-stm32f4.h) +[https://www.st.com/content/ccc/resource/technical/document/reference_manual/3d/6d/5a/66/b4/99/40/d4/DM00031020.pdf/files/DM00031020.pdf/jcr:content/translations/en.DM00031020.pdf](https://www.st.com/content/ccc/resource/technical/document/reference_manual/3d/6d/5a/66/b4/99/40/d4/DM00031020.pdf/files/DM00031020.pdf/jcr:content/translations/en.DM00031020.pdf) + +**Special Requirements**: + +Copy one byte each time. + +How to wait from the write process: read a half word from FLASH_SR, loop until the content is not 1. + +## stm32f7.s + +**Reference**: [https://chromium.googlesource.com/chromiumos/platform/ec/+/master/chip/stm32/registers-stm32f7.h](https://chromium.googlesource.com/chromiumos/platform/ec/+/master/chip/stm32/registers-stm32f7.h) +[https://www.st.com/resource/en/reference_manual/dm00124865-stm32f75xxx-and-stm32f74xxx-advanced-armbased-32bit-mcus-stmicroelectronics.pdf](https://www.st.com/resource/en/reference_manual/dm00124865-stm32f75xxx-and-stm32f74xxx-advanced-armbased-32bit-mcus-stmicroelectronics.pdf) + +Mostly same with `stm32f4.s`. Require establishing a memory barrier after every copy and before checking for finished writing by `dsb sy` + +## stm32f7lv.s + +**Reference**: [https://chromium.googlesource.com/chromiumos/platform/ec/+/master/chip/stm32/registers-stm32f7.h](https://chromium.googlesource.com/chromiumos/platform/ec/+/master/chip/stm32/registers-stm32f7.h) +[https://www.st.com/resource/en/reference_manual/dm00124865-stm32f75xxx-and-stm32f74xxx-advanced-armbased-32bit-mcus-stmicroelectronics.pdf](https://www.st.com/resource/en/reference_manual/dm00124865-stm32f75xxx-and-stm32f74xxx-advanced-armbased-32bit-mcus-stmicroelectronics.pdf) + +**Special Requirements**: + +Mostly same with `stm32f7.s`. Copy one byte each time. + +## stm32l0x.s + +**Special Requirements**: + +Copy one word each time. No wait for write. + +## stm32l4.s + +**Exception**: r2 stores the double word count to be copied. + +`flash_base`: 0x40022000 +`FLASH_BSY`: offset from `flash_base` is 0x12 + +**Reference**: [https://chromium.googlesource.com/chromiumos/platform/ec/+/master/chip/stm32/registers-stm32l4.h](https://chromium.googlesource.com/chromiumos/platform/ec/+/master/chip/stm32/registers-stm32l4.h) +[https://www.st.com/resource/en/reference_manual/dm00310109-stm32l4-series-advanced-armbased-32bit-mcus-stmicroelectronics.pdf](https://www.st.com/resource/en/reference_manual/dm00310109-stm32l4-series-advanced-armbased-32bit-mcus-stmicroelectronics.pdf) + +**Special Requirements**: + +Copy one double word each time (More than one registers are allowed). + +How to wait for the write process: read a half word from `FLASH_BSY`, loop until the lowest bit turns non-1. + +## stm32lx.s + +Same with stm32l0x.s. \ No newline at end of file