diff options
| author | Simon Glass <[email protected]> | 2024-09-26 14:28:51 +0200 |
|---|---|---|
| committer | Tom Rini <[email protected]> | 2024-10-09 22:04:56 -0600 |
| commit | 77a93ae681646437121b8db85b85dad40016fa51 (patch) | |
| tree | 0235b0914fde35b72d58cc959562cc1697f134c0 /README | |
| parent | b03b2a45f9f07bdfb0074adf9c8b4339080a7def (diff) | |
doc: Move the generic memory-documentation to doc/
Move this section of the README into doc/ with some minor updates to
mention SPL and user lower-case hex.
Signed-off-by: Simon Glass <[email protected]>
Acked-by: Heinrich Schuchardt <[email protected]>
Diffstat (limited to 'README')
| -rw-r--r-- | README | 45 |
1 files changed, 0 insertions, 45 deletions
@@ -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: ---------------------- |