Memory layout

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ARM11 Physical memory regions

Address Size Description
0x0 0x10000 Bootrom (super secret code/data @ 0x8000)
0x10000 0x10000 Bootrom mirror
0x10000000 ? IO memory
0x17E00000 0x2000 MPCore private memory region
0x18000000 0x600000 VRAM
0x1FF00000 0x80000 DSP memory
0x1FF80000 0x80000 AXI WRAM
0x20000000 0x8000000 FCRAM

Memory map by firmware

ARM11 Detailed physical memory map

18000000 - 18600000: VRAM

1FF80000 - 1FFAB000: Kernel code
1FFAB000 - 1FFF0000: SlabHeap [temporarily contains boot processes]
1FFF0000 - 1FFF1000: ?
1FFF1000 - 1FFF2000: ?
1FFF2000 - 1FFF3000: ?
1FFF3000 - 1FFF4000: ?
1FFF4000 - 1FFF5000: Exception vectors
1FFF5000 - 1FFF5800: Unused?
1FFF5800 - 1FFF5C00: 256-entry L2 MMU table for VA FF4xx000
1FFF5C00 - 1FFF6000: 256-entry L2 MMU table for VA FF5xx000
1FFF6000 - 1FFF6400: 256-entry L2 MMU table for VA FF6xx000
1FFF6400 - 1FFF6800: 256-entry L2 MMU table for VA FF7xx000
1FFF6800 - 1FFF6C00: 256-entry L2 MMU table for VA FF8xx000
1FFF6C00 - 1FFF7000: 256-entry L2 MMU table for VA FF9xx000
1FFF7000 - 1FFF7400: 256-entry L2 MMU table for VA FFAxx000
1FFF7400 - 1FFF7800: 256-entry L2 MMU table for VA FFBxx000
1FFF7800 - 1FFF7C00: MMU table but unused?
1FFF7C00 - 1FFF8000: 256-entry L2 MMU table for VA FFFxx000 
1FFF8000 - 1FFFC000: 4096-entry L1 MMU table for VA xxx00000 (CPU 0 or 1)
1FFFC000 - 20000000: 4096-entry L1 MMU table for VA xxx00000 (CPU 1 or 0)
20000000 - 28000000: Main memory

ARM11 Detailed virtual memory map

E8000000 - E8600000: mapped VRAM (18000000 - 18600000)

EFF00000 - F0000000: mapped Internal memory (1FF00000 - 20000000)
F0000000 - F8000000: mapped Main memory

FF401000 - FF402000: mapped ? (27FC7000 - 27FC8000)

FF403000 - FF404000: mapped ? (27FC2000 - 27FC3000)

FF405000 - FF406000: mapped ? (27FBB000 - 27FBC000)

FF407000 - FF408000: mapped ? (27FB3000 - 27FB4000)

FF409000 - FF40A000: mapped ? (27F8E000 - 27F8F000)

FFF00000 - FFF45000: mapped SlabHeap 

FFF60000 - FFF8B000: mapped Kernel code

FFFCC000 - FFFCD000: mapped IO I2C second bus (10144000 - 10145000)

FFFCE000 - FFFCF000: mapped IO PDC (10400000 - 10401000)

FFFD0000 - FFFD1000: mapped IO PDN (10141000 - 10142000)

FFFD2000 - FFFD3000: mapped IO PXI (10163000 - 10164000)

FFFD4000 - FFFD5000: mapped IO PAD (10146000 - 10147000)

FFFD6000 - FFFD7000: mapped IO LCD (10202000 - 10203000)

FFFD8000 - FFFD9000: mapped IO ? (10140000 - 10141000)

FFFDA000 - FFFDB000: mapped IO XDMA (10200000 - 10201000)

FFFDC000 - FFFE0000: mapped ? (1FFF8000 - 1FFFC000)

FFFE1000 - FFFE2000: mapped ? (1FFF0000 - 1FFF1000)

FFFE3000 - FFFE4000: mapped ? (1FFF2000 - 1FFF3000)

FFFE5000 - FFFE9000: mapped L1 MMU table for VA xxx00000

FFFEA000 - FFFEB000: mapped ? (1FFF1000 - 1FFF2000)

FFFEC000 - FFFED000: mapped ? (1FFF3000 - 1FFF4000)

FFFEE000 - FFFF0000: mapped IO IRQ (17E00000 - 17E02000)

FFFF0000 - FFFF1000: mapped Exception vectors

FFFF2000 - FFFF6000: mapped L1 MMU table for VA xxx00000

FFFF7000 - FFFF8000: mapped ? (1FFF1000 - 1FFF2000)

FFFF9000 - FFFFA000: mapped ? (1FFF3000 - 1FFF4000)

FFFFB000 - FFFFE000: mapped L2 MMU tables (1FFF5000 - 1FFF8000)

ARM11 User-land memory regions

Virtual Address Base Physical Address Base Region Max Size Description
0x00100000 / 0x14000000 0x03F00000 The ExeFS:/.code is loaded here, executables must be loaded to the 0x00100000 region when the exheader "special memory" flag is clear. The 0x03F00000-byte size restriction only applies when this flag is clear. Executables are usually loaded to 0x14000000 when the exheader "special memory" flag is set, however this address can be arbitrary.
0x08000000 For applications: FCRAM + GSP heap size 0x08000000 Heap mapped by ControlMemory
0x10000000-StackSize .bss physical address - total stack pages StackSize from process exheader Stack for the main-thread, initialized by the ARM11 kernel. The StackSize from the exheader is usually 0x4000, therefore the stack-bottom is usually 0x0FFFC000. The stack for the other threads is normally located in the process .data section however this can be arbitrary.
0x10000000 0x04000000 Shared memory
0x14000000 FCRAM+0 0x08000000 Can be mapped by ControlMemory, this is used for the application's GSP heap.
0x1EC00000 0x10100000 0x01000000 IO registers, the mapped IO pages which each process can access is specified in the CXI exheader.(Applications normally don't have access to registers in this range)
0x1F000000 0x18000000 0x00600000 VRAM, access to this is specified by the exheader.
0x1FF00000 0x1FF00000 0x00080000 DSP memory, access to this is specified by the exheader.
0x1FF80000 FCRAM memory page allocated by the ARM11 kernel. 0x1000 Configuration Memory, all processes have read-only access to this.
0x1FF81000 FCRAM memory page allocated by the ARM11 kernel. 0x1000 Shared page, all processes have read-access to this. Write access to this is specified by the exheader "Shared page writing" kernel flag.

All executable pages are read-only, and data pages have the execute-never permission set. Normally .text from the loaded ExeFS:/.code is the only mapped executable memory. Executable CROs can be loaded into memory, once loaded the CRO .text section memory page permissions are changed via ControlProcessMemory from RW- to R-X. The address and size of each ExeFS:/.code section is stored in the exheader, the permissions for each section is: .text R-X, .rodata R--, .data RW-, and .bss RW-. The loaded .code is mapped to the addresses specified in the exheader by the ARM11 kernel. The stack permissions is initialized by the ARM11 kernel: RW-. The heap permissions is normally RW-.

All userland memory is mapped with RW permissions for privileged-mode. However, normally the ARM11 kernel only uses userland read/write instructions(or checks that the memory can be written from userland first) for accessing memory specified by SVCs.

The virtual memory located below 0x20000000 is process-unique, processes can't directly access memory for other processes. The virtual memory starting at 0x20000000 is only accessible in privileged-mode. When service commands are used, the kernel maps memory in the destination process for input/output buffers, where the addresses in the command received by the process is replaced by this mapped memory. When this is an input buffer, the buffer data is copied to the mapped memory. When this is an output buffer, the data stored in the mapped memory is copied to the destination buffer specified in the command.

The physical address which memory for the application memory-type is mapped to begins at FCRAM+0, the total memory allocated for this memory-type is stored in Configuration_Memory. Applications' exefs:/.code under the application memory-type is mapped at FCRAM + APPMEMALLOC - exefs:/.code size aligned to the page size. The application .bss is mapped at CODEADDR - .bss size aligned down to the page size. Once the application exefs:/.code, .bss, and stack are mapped, APPMEMALLOC is set to APPMEMALLOC - (stacksize + bss_size + codesize), where stacksize, bss_size, and code_size are aligned to the page size.

System memory details

0xFFFF9004 Pointer to the current KProcess instance

Handles

The handle 0xFFFF8001 is a reference to the current KProcess.

VRAM Map While Running Webbrowser

  • 0x1e6000-0x22C500 -- top screen framebuffer 0(240x400x3)
  • 0x22C800-0x272D00 -- top screen framebuffer 1(240x400x3)
  • 0x273000-0x2B9500 -- top screen framebuffer 2(240x400x3)
  • 0x2B9800-0x2FFD00 -- top screen framebuffer 3(240x400x3)
  • 0x48F000-0x4C7400 -- bottom screen framebuffer 0(240x320x3)
  • 0x4C7800-0x4FF800 -- bottom screen framebuffer 1(240x320x3)