Отправлено MemoryTest 29 марта 2004 г. 12:37 В ответ на: кто разбирается в ARM MMU - объясните смысл R13 (CP15) отправлено yes 29 марта 2004 г. 10:36

The virtual address produced by the processor core going to the IDC and MMU may be
relocated if it lies in the bottom 32MB of the virtual address (that is, virtual address bits
[31:25] = 0000000) by the substitution of the seven bits [31:25] of the ProcessID
register in the CP15 Coprocessor.
The two instructions fetched immediately following an instruction to change the
Process Identifier are fetched with a relocation to the previous Process Identifier, if the
addresses of the instructions being fetched lie within the range of addresses to be
relocated. In this behaviour, a change to the Process Identifier exhibits similar
behaviour to a delayed branch.
On reset, the Process Identifier register bits [31:25] are set to 0000000, thus disabling
all relocation. For this reason, the low address reset exception vector is effectively
never relocated by this mechanism.
Relocation of the virtual address only occurs if the WinCE Enhancements pin is at a
logic “1”; that is, the WinCE Enhancements are enabled.
Note All addresses produced by the processor core undergo this translation if they lie in the
appropriate address range; this includes the exception vectors if they are configured to
lie in the bottom of the virtual memory map (this configuration is determined by the Vbit
in the CP15 Control Register).

• я так и предположил. писал вопрос слишком долго :) — yes   (29.03.2004 13:09, пустое)