[PATCH v3 0/2] docs/LoongArch: Add English and Chinese versions of booting

[PATCH v3 0/2] docs/LoongArch: Add English and Chinese versions of booting

[Yanteng Si]

v3:

* Add a description about boot parameters (a0=efi_boot a1=cmdline a2=systemtable),
  and then rename the file to booting.rst.
* remove some blank line.

v2:
* Fix magic start address.
* res14 -> res4.

v1:
* Add boot image header.
* Translate boot-image-header into Chinese.

Yanteng Si (2):
  docs/LoongArch: Add booting
  docs/zh_CN: Add booting Chinese translation

 Documentation/loongarch/booting.rst           | 89 +++++++++++++++++++
 Documentation/loongarch/index.rst             |  1 +
 .../translations/zh_CN/loongarch/booting.rst  | 86 ++++++++++++++++++
 .../translations/zh_CN/loongarch/index.rst    |  1 +
 4 files changed, 177 insertions(+)
 create mode 100644 Documentation/loongarch/booting.rst
 create mode 100644 Documentation/translations/zh_CN/loongarch/booting.rst

-- 
2.31.1

[PATCH v3 1/2] docs/LoongArch: Add booting

[Yanteng Si]

Describes the meaning and value of the image header field.

Suggested-by: Xiaotian Wu <wuxiaotian@loongson.cn>
Signed-off-by: Yanteng Si <siyanteng@loongson.cn>
---
 Documentation/loongarch/booting.rst | 89 +++++++++++++++++++++++++++++
 Documentation/loongarch/index.rst   |  1 +
 2 files changed, 90 insertions(+)
 create mode 100644 Documentation/loongarch/booting.rst

diff --git a/Documentation/loongarch/booting.rst b/Documentation/loongarch/booting.rst
new file mode 100644
index 000000000000..f59de4eea39d
--- /dev/null
+++ b/Documentation/loongarch/booting.rst
@@ -0,0 +1,89 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+====================
+启动 LoongArch Linux
+====================
+
+:Author: Yanteng Si <siyanteng@loongson.cn>
+:Date:   18 Nov 2022
+
+BootLoader passing parameters to the kernel
+===========================================
+
+LoongArch is an ACPI system and the information that needs to be passed
+to the kernel are memmap, initrd, cmdline, etc.
+On LoongArch machines, the BootLoader (EFISTUB/Grub) will pass three
+valid parameters to the kernel, which are::
+
+      a0 = efi_boot
+      a1 = cmdline
+      a2 = systemtable
+
+where a1 is a pointer to cmdline, a2 contains the memmap, initrd,
+cmdline and other information that needs to be passed to the kernel.
+
+Boot image header in LoongArch Linux
+====================================
+
+The following 64-byte header is present in decompressed Linux
+kernel image::
+
+	u32	MZ_MAGIC		/* "MZ", MS-DOS header */
+	u32	res0 = 0		/* reserved */
+	u64	kernel_entry		/* Kernel entry point */
+	u64	_end - _text		/* Kernel image effective size */
+	u64	0			/* Kernel image load offset from start of RAM */
+	u64	res1 = 0		/* reserved */
+	u64	res2 = 0		/* reserved */
+	u64	res3 = 0		/* reserved */
+	u32	res4 = 0		/* reserved */
+	u32	pe_header - _head	/* Offset to the PE header */
+
+Header notes
+============
+
+Currently, LoongArch has removed the "magic" field.
+
+According to the EFI specification, the PE/COFF image file header is
+required at the beginning of the kernel image; the LoongArch kernel
+supports the EFI stub, so the first two bytes of the kernel image header
+are "MZ" magic characters, and 0x3c should point to the rest of the
+PE/COFF file header, between which The kernel entry point, image
+effectivesize, and image load offset layout are as follows::
+
+          +-----------------------------------------------+
+          |  0  |  1  |  2  |  3  |  4  |  5  |  6  |  7  |
+          +-----------------------------------------------+
+    0x00: |       MZ_MAGIC        |          res0         |
+          +-----------------------------------------------+
+    0x08: |                 kernel_entry                  |
+          +-----------------------------------------------+
+    0x10: |                  _end - _text                 |
+          +-----------------------------------------------+
+    0x18: |                       0                       |
+          +-----------------------------------------------+
+    0x20: |                      res1                     |
+          +-----------------------------------------------+
+    0x28: |                      res2                     |
+          +-----------------------------------------------+
+    0x30: |                      res3                     |
+          +-----------------------------------------------+
+    0x38: |          res4         |       PE header       |
+          +-----------------------------------------------+
+
+All bit fields are in little endian:
+
+    - MZ: Effective length of 2 bytes;
+
+    - kernel entry point: leaving 6 bytes blank in front, starting
+      from 0x8, with a effective length of 8 bytes;
+
+    - kernel image effective size: Immediately following the kernel
+      entry point, with a effective length of 8 bytes, this field is
+      required for the bootloader;
+
+    - kernel image load offset: Immediately following the kernel
+      image effective size, with a effective length of 8 bytes;
+
+    - Offset to the PE header: leaving 28 bytes blank in front,
+      starting from 0x3c, with a effective length of 4 bytes.
diff --git a/Documentation/loongarch/index.rst b/Documentation/loongarch/index.rst
index aaba648db907..df0174d6d227 100644
--- a/Documentation/loongarch/index.rst
+++ b/Documentation/loongarch/index.rst
@@ -10,6 +10,7 @@ LoongArch Architecture
 
    introduction
    irq-chip-model
+   booting
 
    features
 
-- 
2.31.1

[PATCH v3 2/2] docs/zh_CN: Add booting Chinese translation

[Yanteng Si]

Translate ../loongarch/booting.rst into Chinese.

Suggested-by: Xiaotian Wu <wuxiaotian@loongson.cn>
Signed-off-by: Yanteng Si <siyanteng@loongson.cn>
---
 .../translations/zh_CN/loongarch/booting.rst  | 86 +++++++++++++++++++
 .../translations/zh_CN/loongarch/index.rst    |  1 +
 2 files changed, 87 insertions(+)
 create mode 100644 Documentation/translations/zh_CN/loongarch/booting.rst

diff --git a/Documentation/translations/zh_CN/loongarch/booting.rst b/Documentation/translations/zh_CN/loongarch/booting.rst
new file mode 100644
index 000000000000..fd82d46bee4c
--- /dev/null
+++ b/Documentation/translations/zh_CN/loongarch/booting.rst
@@ -0,0 +1,86 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+.. include:: ../disclaimer-zh_CN.rst
+
+:Original: Documentation/loongarch/booting.rst
+
+:翻译:
+
+ 司延腾 Yanteng Si <siyanteng@loongson.cn>
+
+====================
+启动 LoongArch Linux
+====================
+
+:作者: 司延腾 <siyanteng@loongson.cn>
+:日期: 2022年11月18日
+
+BootLoader传递给内核的信息
+==========================
+
+LoongArch是纯ACPI系统，需要传递给内核的信息有memmap、initrd、cmdline等。
+而在LoongArch机器上，BootLoader（EFISTUB/Grub）会给内核传递三个有效参数，
+它们分别是::
+
+      a0 = efi_boot
+      a1 = cmdline
+      a2 = systemtable
+
+其中a1是指向cmdline的指针，a2则包含了需要传递给内核的memmap、initrd、cmdline……
+
+LoongArch Linux启动镜像文件头
+=============================
+
+在非压缩的Linux内核镜像中存在以下64字节的文件头::
+
+	u32	MZ_MAGIC		/* "MZ", MS-DOS 头 */
+	u32	res0 = 0		/* 保留 */
+	u64	kernel_entry		/* 内核入口点 */
+	u64	_end - _text		/* 内核镜像有效大小 */
+	u64	0			/* 从RAM开始的加载内核镜像的偏移量 */
+	u64	res1 = 0		/* 保留 */
+	u64	res2 = 0		/* 保留 */
+	u64	res3 = 0		/* 保留 */
+	u32	res4 = 0		/* 保留 */
+	u32	pe_header - _head	/* 到PE头的偏移量 */
+
+镜像头注释
+==========
+
+目前LoongArch已经移除“magic”结构体成员。
+
+按照EFI规范的规定，在内核镜像的开始需要PE/COFF镜像文件头。当前LoongArch内核支持
+EFI stub，故内核镜像头最开始两字节为“MZ”魔术字符，且0x3c处应指向PE/COFF文件头的
+其余部分，在此之间，内核的入口点、有效镜像大小、镜像加载偏移布局如下::
+
+          +-----------------------------------------------+
+          |  0  |  1  |  2  |  3  |  4  |  5  |  6  |  7  |
+          +-----------------------------------------------+
+    0x00: |       MZ_MAGIC        |          res0         |
+          +-----------------------------------------------+
+    0x08: |                 kernel_entry                  |
+          +-----------------------------------------------+
+    0x10: |                  _end - _text                 |
+          +-----------------------------------------------+
+    0x18: |                       0                       |
+          +-----------------------------------------------+
+    0x20: |                      res1                     |
+          +-----------------------------------------------+
+    0x28: |                      res2                     |
+          +-----------------------------------------------+
+    0x30: |                      res3                     |
+          +-----------------------------------------------+
+    0x38: |          res4         |       PE header       |
+          +-----------------------------------------------+
+
+所有的位域都是小端序：
+
+    - MZ：有效长度为2字节；
+
+    - 内核入口点：前留空6个字节，自0x8开始，有效长度为8字节；
+
+    - 内核镜像有效大小：紧接内核入口点，有效长度为8字节，该成员对于引导器来说是必须的；
+
+    - 内核镜像加载偏移：紧接内核镜像有效大小，有效长度为8字节；
+
+    - 到PE头的偏移量：前留空28字节，自0x3c开始,有效长度为4字节。
diff --git a/Documentation/translations/zh_CN/loongarch/index.rst b/Documentation/translations/zh_CN/loongarch/index.rst
index 7d23eb78379d..8609ade41981 100644
--- a/Documentation/translations/zh_CN/loongarch/index.rst
+++ b/Documentation/translations/zh_CN/loongarch/index.rst
@@ -15,6 +15,7 @@ LoongArch体系结构
 
    introduction
    irq-chip-model
+   booting
 
    features
 
-- 
2.31.1