diff options
Diffstat (limited to 'docs/firmware-design.md')
-rw-r--r-- | docs/firmware-design.md | 52 |
1 files changed, 43 insertions, 9 deletions
diff --git a/docs/firmware-design.md b/docs/firmware-design.md index 41aaf7f2..be1f5f30 100644 --- a/docs/firmware-design.md +++ b/docs/firmware-design.md @@ -1212,14 +1212,19 @@ The following list describes the memory layout on the FVP: * BL2 is loaded below BL3-1. -* The TSP is loaded as the BL3-2 image at the base of either the Trusted - SRAM or Trusted DRAM. When loaded into Trusted SRAM, its NOBITS sections - are allowed to overlay BL2. +* BL3-2 can be loaded in one of the following locations: -This memory layout is designed to give the BL3-2 image as much memory as -possible when it is loaded into Trusted SRAM. Depending on the location of the -TSP, it will result in different memory maps, illustrated by the following -diagrams. + * Trusted SRAM + * Trusted DRAM + * Secure region of DRAM (top 16MB of DRAM configured by the TrustZone + controller) + +When BL3-2 is loaded into Trusted SRAM, its NOBITS sections are allowed to +overlay BL2. This memory layout is designed to give the BL3-2 image as much +memory as possible when it is loaded into Trusted SRAM. + +The location of the BL3-2 image will result in different memory maps. This is +illustrated in the following diagrams using the TSP as an example. **TSP in Trusted SRAM (default option):** @@ -1267,8 +1272,37 @@ diagrams. | BL1 (ro) | 0x00000000 +----------+ -Loading the TSP image in Trusted DRAM doesn't change the memory layout of the -other boot loader images in Trusted SRAM. +**TSP in the TZC-Secured DRAM:** + + DRAM + 0xffffffff +----------+ + | BL3-2 | (secure) + 0xff000000 +----------+ + | | + : : (non-secure) + | | + 0x80000000 +----------+ + + Trusted SRAM + 0x04040000 +----------+ loaded by BL2 ------------------ + | BL1 (rw) | <<<<<<<<<<<<< | BL3-1 NOBITS | + |----------| <<<<<<<<<<<<< |----------------| + | | <<<<<<<<<<<<< | BL3-1 PROGBITS | + |----------| ------------------ + | BL2 | + |----------| + | | + 0x04001000 +----------+ + | Shared | + 0x04000000 +----------+ + + Trusted ROM + 0x04000000 +----------+ + | BL1 (ro) | + 0x00000000 +----------+ + +Moving the TSP image out of the Trusted SRAM doesn't change the memory layout +of the other boot loader images in Trusted SRAM. #### Memory layout on Juno ARM development platform |