From ae68ff085724dd35d60151bd153e80b8b0776873 Mon Sep 17 00:00:00 2001 From: Joel Sherrill Date: Tue, 27 May 1997 12:40:11 +0000 Subject: Initial revision --- doc/supplements/i960/memmodel.t | 53 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 53 insertions(+) create mode 100644 doc/supplements/i960/memmodel.t (limited to 'doc/supplements/i960/memmodel.t') diff --git a/doc/supplements/i960/memmodel.t b/doc/supplements/i960/memmodel.t new file mode 100644 index 0000000000..ce057bc94c --- /dev/null +++ b/doc/supplements/i960/memmodel.t @@ -0,0 +1,53 @@ +@c +@c COPYRIGHT (c) 1988-1997. +@c On-Line Applications Research Corporation (OAR). +@c All rights reserved. +@c + +@ifinfo +@node Memory Model, Memory Model Introduction, Calling Conventions Leaf Procedures, Top +@end ifinfo +@chapter Memory Model +@ifinfo +@menu +* Memory Model Introduction:: +* Memory Model Flat Memory Model:: +@end menu +@end ifinfo + +@ifinfo +@node Memory Model Introduction, Memory Model Flat Memory Model, Memory Model, Memory Model +@end ifinfo +@section Introduction + +A processor may support any combination of memory +models ranging from pure physical addressing to complex demand +paged virtual memory systems. RTEMS supports a flat memory +model which ranges contiguously over the processor's allowable +address space. RTEMS does not support segmentation or virtual +memory of any kind. The appropriate memory model for RTEMS +provided by the targeted processor and related characteristics +of that model are described in this chapter. + +@ifinfo +@node Memory Model Flat Memory Model, Interrupt Processing, Memory Model Introduction, Memory Model +@end ifinfo +@section Flat Memory Model + +The i960CA supports a flat 32-bit address space with +addresses ranging from 0x00000000 to 0xFFFFFFFF (4 gigabytes). +Although the i960CA reserves portions of this address space, +application code and data may be placed in any non-reserved +areas. Each address is represented by a 32-bit value and is +byte addressable. The address may be used to reference a single +byte, half-word (2-bytes), word (4 bytes), double-word (8 +bytes), triple-word (12 bytes) or quad-word (16 bytes). The +i960CA does not support virtual memory or segmentation. + +The i960CA allows the memory space to be partitioned +into sixteen regions which may be configured individually as big +or little endian. RTEMS assumes that the memory regions in +which its code, data, and the RTEMS Workspace reside are +configured as little endian. + + -- cgit v1.2.3