From d755cbd36f5b4410994bcd468aee983471ab7167 Mon Sep 17 00:00:00 2001 From: Amar Takhar Date: Sat, 16 Jan 2016 20:13:02 -0500 Subject: Split document into seperate files by section. --- cpu_supplement/superh.rst | 150 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 150 insertions(+) create mode 100644 cpu_supplement/superh.rst (limited to 'cpu_supplement/superh.rst') diff --git a/cpu_supplement/superh.rst b/cpu_supplement/superh.rst new file mode 100644 index 0000000..9d62dba --- /dev/null +++ b/cpu_supplement/superh.rst @@ -0,0 +1,150 @@ +SuperH Specific Information +########################### + +This chapter discusses the SuperH architecture dependencies +in this port of RTEMS. The SuperH family has a wide variety +of implementations by a wide range of vendors. Consequently, +there are many, many CPU models within it. + +**Architecture Documents** + +For information on the SuperH architecture, +refer to the following documents available from VENDOR +(:file:`http//www.XXX.com/`): + +- *SuperH Family Reference, VENDOR, PART NUMBER*. + +CPU Model Dependent Features +============================ + +This chapter presents the set of features which vary +across SuperH implementations and are of importance to RTEMS. +The set of CPU model feature macros are defined in the file``cpukit/score/cpu/sh/sh.h`` based upon the particular CPU +model specified on the compilation command line. + +Another Optional Feature +------------------------ + +The macro XXX + +Calling Conventions +=================== + +Calling Mechanism +----------------- + +All RTEMS directives are invoked using a ``XXX`` +instruction and return to the user application via the``XXX`` instruction. + +Register Usage +-------------- + +The SH1 has 16 general registers (r0..r15). + +- r0..r3 used as general volatile registers + +- r4..r7 used to pass up to 4 arguments to functions, arguments + above 4 are + passed via the stack) + +- r8..13 caller saved registers (i.e. push them to the stack if you + need them inside of a function) + +- r14 frame pointer + +- r15 stack pointer + +Parameter Passing +----------------- + +XXX + +Memory Model +============ + +Flat Memory Model +----------------- + +The SuperH family supports a flat 32-bit address +space with addresses ranging from 0x00000000 to 0xFFFFFFFF (4 +gigabytes). Each address is represented by a 32-bit value and +is byte addressable. The address may be used to reference a +single byte, word (2-bytes), or long word (4 bytes). Memory +accesses within this address space are performed in big endian +fashion by the processors in this family. + +Some of the SuperH family members support virtual memory and +segmentation. RTEMS does not support virtual memory or +segmentation on any of the SuperH family members. It is the +responsibility of the BSP to initialize the mapping for +a flat memory model. + +Interrupt Processing +==================== + +Although RTEMS hides many of the processor dependent +details of interrupt processing, it is important to understand +how the RTEMS interrupt manager is mapped onto the processor’s +unique architecture. Discussed in this chapter are the MIPS’s +interrupt response and control mechanisms as they pertain to +RTEMS. + +Vectoring of an Interrupt Handler +--------------------------------- + +Upon receipt of an interrupt the XXX family +members with separate interrupt stacks automatically perform the +following actions: + +- TBD + +A nested interrupt is processed similarly by these +CPU models with the exception that only a single ISF is placed +on the interrupt stack and the current stack need not be +switched. + +Interrupt Levels +---------------- + +TBD + +Default Fatal Error Processing +============================== + +The default fatal error handler for this architecture disables processor +interrupts, places the error code in *XXX*, and executes a ``XXX`` +instruction to simulate a halt processor instruction. + +Symmetric Multiprocessing +========================= + +SMP is not supported. + +Thread-Local Storage +==================== + +Thread-local storage is not implemented. + +Board Support Packages +====================== + +System Reset +------------ + +An RTEMS based application is initiated or +re-initiated when the processor is reset. When the +processor is reset, it performs the following actions: + +- TBD + +Processor Initialization +------------------------ + +TBD + +.. COMMENT: COPYRIGHT (c) 1988-2002. + +.. COMMENT: On-Line Applications Research Corporation (OAR). + +.. COMMENT: All rights reserved. + -- cgit v1.2.3