Hello Simon,
Am Thu, Sep 19, 2024 at 05:14:22PM +0200 schrieb Simon Glass:
Move this section of the README into doc/ with some minor updates to mention SPL and user lower-case hex.
Maybe try not to rewrap unchanged paragraphs, so `git show --color-moved` can detect those as just moved?
Signed-off-by: Simon Glass sjg@chromium.org
README | 45 ------------------------------------------ doc/develop/index.rst | 1 + doc/develop/memory.rst | 45 ++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 46 insertions(+), 45 deletions(-) create mode 100644 doc/develop/memory.rst
diff --git a/README b/README index 4be1e8c22a0..d73042406b6 100644 --- a/README +++ b/README @@ -2516,51 +2516,6 @@ On RISC-V, the following registers are used:
==> U-Boot will use gp to hold a pointer to the global data-Memory Management:
-U-Boot runs in system state and uses physical addresses, i.e. the -MMU is not used either for address mapping nor for memory protection.
-The available memory is mapped to fixed addresses using the memory -controller. In this process, a contiguous block is formed for each -memory type (Flash, SDRAM, SRAM), even when it consists of several -physical memory banks.
-U-Boot is installed in the first 128 kB of the first Flash bank (on -TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After -booting and sizing and initializing DRAM, the code relocates itself -to the upper end of DRAM. Immediately below the U-Boot code some -memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN -configuration setting]. Below that, a structure with global Board -Info data is placed, followed by the stack (growing downward).
-Additionally, some exception handler code is copied to the low 8 kB -of DRAM (0x00000000 ... 0x00001FFF).
-So a typical memory configuration with 16 MB of DRAM could look like -this:
- 0x0000 0000 Exception Vector code
:- 0x0000 1FFF
- 0x0000 2000 Free for Application Use
::::- 0x00FB FF20 Monitor Stack (Growing downward)
- 0x00FB FFAC Board Info Data and permanent copy of global data
- 0x00FC 0000 Malloc Arena
:- 0x00FD FFFF
- 0x00FE 0000 RAM Copy of Monitor Code
- ... eventually: LCD or video framebuffer
- ... eventually: pRAM (Protected RAM - unchanged by reset)
- 0x00FF FFFF [End of RAM]
System Initialization:
diff --git a/doc/develop/index.rst b/doc/develop/index.rst index 0d0e60ab56c..cbea38d4323 100644 --- a/doc/develop/index.rst +++ b/doc/develop/index.rst @@ -13,6 +13,7 @@ General codingstyle designprinciples docstyle
- memory patman process release_cycle
diff --git a/doc/develop/memory.rst b/doc/develop/memory.rst new file mode 100644 index 00000000000..fa1ae5e97ed --- /dev/null +++ b/doc/develop/memory.rst @@ -0,0 +1,45 @@ +.. SPDX-License-Identifier: GPL-2.0+:
+Memory Management +-----------------
+U-Boot runs in system state and uses physical addresses, i.e. the +MMU is not used either for address mapping nor for memory protection.
+The available memory is mapped to fixed addresses using the +memory-controller. In this process, a contiguous block is formed for each +memory type (Flash, SDRAM, SRAM), even when it consists of several +physical-memory banks.
+U-Boot is installed in XIP flash memory, or may be loaded into a lower region of +RAM by a secondary program loader (SPL). After +booting and sizing and initialising DRAM, the code relocates itself +to the upper end of DRAM. Immediately below the U-Boot code some +memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN +configuration setting]. Below that, a structure with global Board-Info +data is placed, followed by the stack (growing downward).
+Additionally, some exception handler code may be copied to the low 8 kB +of DRAM (0x00000000 ... 0x00001fff).
+So a typical memory configuration with 16 MB of DRAM could look like +this::
- 0x0000 0000 Exception Vector code
:- 0x0000 1fff
- 0x0000 2000 Free for Application Use
::::- 0x00fb ff20 Monitor Stack (Growing downward)
- 0x00fb ffac Board Info Data and permanent copy of global data
- 0x00fc 0000 Malloc Arena
Arena?
`make htmldocs` runs fine, page looks okay, thus:
Acked-by: Alexander Dahl ada@thorsis.com
Greets Alex
:- 0x00fd ffff
- 0x00fe 0000 RAM Copy of Monitor Code
- ... eventually: LCD or video framebuffer
- ... eventually: pRAM (Protected RAM - unchanged by reset)
- 0x00ff ffff [End of RAM]
-- 2.43.0