/* * Mips CPU Dependent Header File * * Conversion to MIPS port by Alan Cudmore and * Joel Sherrill . * * These changes made the code conditional on standard cpp predefines, * merged the mips1 and mips3 code sequences as much as possible, * and moved some of the assembly code to C. Alan did much of the * initial analysis and rework. Joel took over from there and * wrote the JMR3904 BSP so this could be tested. Joel also * added the new interrupt vectoring support in libcpu and * tried to better support the various interrupt controllers. * * Original MIP64ORION port by Craig Lebakken * COPYRIGHT (c) 1996 by Transition Networks Inc. * * To anyone who acknowledges that this file is provided "AS IS" * without any express or implied warranty: * permission to use, copy, modify, and distribute this file * for any purpose is hereby granted without fee, provided that * the above copyright notice and this notice appears in all * copies, and that the name of Transition Networks not be used in * advertising or publicity pertaining to distribution of the * software without specific, written prior permission. * Transition Networks makes no representations about the suitability * of this software for any purpose. * * COPYRIGHT (c) 1989-2001. * On-Line Applications Research Corporation (OAR). * * The license and distribution terms for this file may be * found in the file LICENSE in this distribution or at * http://www.OARcorp.com/rtems/license.html. * * $Id$ */ #ifndef __CPU_h #define __CPU_h #ifdef __cplusplus extern "C" { #endif #include /* pick up machine definitions */ #ifndef ASM #include #endif /* conditional compilation parameters */ /* * Should the calls to _Thread_Enable_dispatch be inlined? * * If TRUE, then they are inlined. * If FALSE, then a subroutine call is made. * * Basically this is an example of the classic trade-off of size * versus speed. Inlining the call (TRUE) typically increases the * size of RTEMS while speeding up the enabling of dispatching. * [NOTE: In general, the _Thread_Dispatch_disable_level will * only be 0 or 1 unless you are in an interrupt handler and that * interrupt handler invokes the executive.] When not inlined * something calls _Thread_Enable_dispatch which in turns calls * _Thread_Dispatch. If the enable dispatch is inlined, then * one subroutine call is avoided entirely.] */ #define CPU_INLINE_ENABLE_DISPATCH FALSE /* * Should the body of the search loops in _Thread_queue_Enqueue_priority * be unrolled one time? In unrolled each iteration of the loop examines * two "nodes" on the chain being searched. Otherwise, only one node * is examined per iteration. * * If TRUE, then the loops are unrolled. * If FALSE, then the loops are not unrolled. * * The primary factor in making this decision is the cost of disabling * and enabling interrupts (_ISR_Flash) versus the cost of rest of the * body of the loop. On some CPUs, the flash is more expensive than * one iteration of the loop body. In this case, it might be desirable * to unroll the loop. It is important to note that on some CPUs, this * code is the longest interrupt disable period in RTEMS. So it is * necessary to strike a balance when setting this parameter. */ #define CPU_UNROLL_ENQUEUE_PRIORITY TRUE /* * Does RTEMS manage a dedicated interrupt stack in software? * * If TRUE, then a stack is allocated in _Interrupt_Manager_initialization. * If FALSE, nothing is done. * * If the CPU supports a dedicated interrupt stack in hardware, * then it is generally the responsibility of the BSP to allocate it * and set it up. * * If the CPU does not support a dedicated interrupt stack, then * the porter has two options: (1) execute interrupts on the * stack of the interrupted task, and (2) have RTEMS manage a dedicated * interrupt stack. * * If this is TRUE, CPU_ALLOCATE_INTERRUPT_STACK should also be TRUE. * * Only one of CPU_HAS_SOFTWARE_INTERRUPT_STACK and * CPU_HAS_HARDWARE_INTERRUPT_STACK should be set to TRUE. It is * possible that both are FALSE for a particular CPU. Although it * is unclear what that would imply about the interrupt processing * procedure on that CPU. */ #define CPU_HAS_SOFTWARE_INTERRUPT_STACK FALSE /* * Does this CPU have hardware support for a dedicated interrupt stack? * * If TRUE, then it must be installed during initialization. * If FALSE, then no installation is performed. * * If this is TRUE, CPU_ALLOCATE_INTERRUPT_STACK should also be TRUE. * * Only one of CPU_HAS_SOFTWARE_INTERRUPT_STACK and * CPU_HAS_HARDWARE_INTERRUPT_STACK should be set to TRUE. It is * possible that both are FALSE for a particular CPU. Although it * is unclear what that would imply about the interrupt processing * procedure on that CPU. */ #define CPU_HAS_HARDWARE_INTERRUPT_STACK FALSE /* * Does RTEMS allocate a dedicated interrupt stack in the Interrupt Manager? * * If TRUE, then the memory is allocated during initialization. * If FALSE, then the memory is allocated during initialization. * * This should be TRUE is CPU_HAS_SOFTWARE_INTERRUPT_STACK is TRUE * or CPU_INSTALL_HARDWARE_INTERRUPT_STACK is TRUE. */ #define CPU_ALLOCATE_INTERRUPT_STACK FALSE /* * Does the RTEMS invoke the user's ISR with the vector number and * a pointer to the saved interrupt frame (1) or just the vector * number (0)? * */ #define CPU_ISR_PASSES_FRAME_POINTER 1 /* * Does the CPU have hardware floating point? * * If TRUE, then the RTEMS_FLOATING_POINT task attribute is supported. * If FALSE, then the RTEMS_FLOATING_POINT task attribute is ignored. * * If there is a FP coprocessor such as the i387 or mc68881, then * the answer is TRUE. * * The macro name "MIPS_HAS_FPU" should be made CPU specific. * It indicates whether or not this CPU model has FP support. For * example, it would be possible to have an i386_nofp CPU model * which set this to false to indicate that you have an i386 without * an i387 and wish to leave floating point support out of RTEMS. */ #if ( MIPS_HAS_FPU == 1 ) #define CPU_HARDWARE_FP TRUE #else #define CPU_HARDWARE_FP FALSE #endif /* * Are all tasks RTEMS_FLOATING_POINT tasks implicitly? * * If TRUE, then the RTEMS_FLOATING_POINT task attribute is assumed. * If FALSE, then the RTEMS_FLOATING_POINT task attribute is followed. * * So far, the only CPU in which this option has been used is the * HP PA-RISC. The HP C compiler and gcc both implicitly use the * floating point registers to perform integer multiplies. If * a function which you would not think utilize the FP unit DOES, * then one can not easily predict which tasks will use the FP hardware. * In this case, this option should be TRUE. * * If CPU_HARDWARE_FP is FALSE, then this should be FALSE as well. */ #define CPU_ALL_TASKS_ARE_FP FALSE /* * Should the IDLE task have a floating point context? * * If TRUE, then the IDLE task is created as a RTEMS_FLOATING_POINT task * and it has a floating point context which is switched in and out. * If FALSE, then the IDLE task does not have a floating point context. * * Setting this to TRUE negatively impacts the time required to preempt * the IDLE task from an interrupt because the floating point context * must be saved as part of the preemption. */ #define CPU_IDLE_TASK_IS_FP FALSE /* * Should the saving of the floating point registers be deferred * until a context switch is made to another different floating point * task? * * If TRUE, then the floating point context will not be stored until * necessary. It will remain in the floating point registers and not * disturned until another floating point task is switched to. * * If FALSE, then the floating point context is saved when a floating * point task is switched out and restored when the next floating point * task is restored. The state of the floating point registers between * those two operations is not specified. * * If the floating point context does NOT have to be saved as part of * interrupt dispatching, then it should be safe to set this to TRUE. * * Setting this flag to TRUE results in using a different algorithm * for deciding when to save and restore the floating point context. * The deferred FP switch algorithm minimizes the number of times * the FP context is saved and restored. The FP context is not saved * until a context switch is made to another, different FP task. * Thus in a system with only one FP task, the FP context will never * be saved or restored. */ #define CPU_USE_DEFERRED_FP_SWITCH TRUE /* * Does this port provide a CPU dependent IDLE task implementation? * * If TRUE, then the routine _CPU_Internal_threads_Idle_thread_body * must be provided and is the default IDLE thread body instead of * _Internal_threads_Idle_thread_body. * * If FALSE, then use the generic IDLE thread body if the BSP does * not provide one. * * This is intended to allow for supporting processors which have * a low power or idle mode. When the IDLE thread is executed, then * the CPU can be powered down. * * The order of precedence for selecting the IDLE thread body is: * * 1. BSP provided * 2. CPU dependent (if provided) * 3. generic (if no BSP and no CPU dependent) */ /* we can use the low power wait instruction for the IDLE thread */ #define CPU_PROVIDES_IDLE_THREAD_BODY TRUE /* * Does the stack grow up (toward higher addresses) or down * (toward lower addresses)? * * If TRUE, then the grows upward. * If FALSE, then the grows toward smaller addresses. */ /* our stack grows down */ #define CPU_STACK_GROWS_UP FALSE /* * The following is the variable attribute used to force alignment * of critical RTEMS structures. On some processors it may make * sense to have these aligned on tighter boundaries than * the minimum requirements of the compiler in order to have as * much of the critical data area as possible in a cache line. * * The placement of this macro in the declaration of the variables * is based on the syntactically requirements of the GNU C * "__attribute__" extension. For example with GNU C, use * the following to force a structures to a 32 byte boundary. * * __attribute__ ((aligned (32))) * * NOTE: Currently only the Priority Bit Map table uses this feature. * To benefit from using this, the data must be heavily * used so it will stay in the cache and used frequently enough * in the executive to justify turning this on. */ /* our cache line size is 16 bytes */ #if __GNUC__ #define CPU_STRUCTURE_ALIGNMENT __attribute__ ((aligned (16))) #else #define CPU_STRUCTURE_ALIGNMENT #endif /* * Define what is required to specify how the network to host conversion * routines are handled. */ #define CPU_HAS_OWN_HOST_TO_NETWORK_ROUTINES FALSE #define CPU_BIG_ENDIAN TRUE #define CPU_LITTLE_ENDIAN FALSE /* * The following defines the number of bits actually used in the * interrupt field of the task mode. How those bits map to the * CPU interrupt levels is defined by the routine _CPU_ISR_Set_level(). */ #define CPU_MODES_INTERRUPT_MASK 0x000000ff /* * Processor defined structures * * Examples structures include the descriptor tables from the i386 * and the processor control structure on the i960ca. */ /* may need to put some structures here. */ /* * Contexts * * Generally there are 2 types of context to save. * 1. Interrupt registers to save * 2. Task level registers to save * * This means we have the following 3 context items: * 1. task level context stuff:: Context_Control * 2. floating point task stuff:: Context_Control_fp * 3. special interrupt level context :: Context_Control_interrupt * * On some processors, it is cost-effective to save only the callee * preserved registers during a task context switch. This means * that the ISR code needs to save those registers which do not * persist across function calls. It is not mandatory to make this * distinctions between the caller/callee saves registers for the * purpose of minimizing context saved during task switch and on interrupts. * If the cost of saving extra registers is minimal, simplicity is the * choice. Save the same context on interrupt entry as for tasks in * this case. * * Additionally, if gdb is to be made aware of RTEMS tasks for this CPU, then * care should be used in designing the context area. * * On some CPUs with hardware floating point support, the Context_Control_fp * structure will not be used or it simply consist of an array of a * fixed number of bytes. This is done when the floating point context * is dumped by a "FP save context" type instruction and the format * is not really defined by the CPU. In this case, there is no need * to figure out the exact format -- only the size. Of course, although * this is enough information for RTEMS, it is probably not enough for * a debugger such as gdb. But that is another problem. */ #ifndef ASSEMBLY_ONLY /* WARNING: If this structure is modified, the constants in cpu.h must be updated. */ #if __mips == 1 #define __MIPS_REGISTER_TYPE unsigned32 #define __MIPS_FPU_REGISTER_TYPE unsigned32 #elif __mips == 3 #define __MIPS_REGISTER_TYPE unsigned64 #define __MIPS_FPU_REGISTER_TYPE unsigned64 #else #error "mips register size: unknown architecture level!!" #endif typedef struct { __MIPS_REGISTER_TYPE s0; __MIPS_REGISTER_TYPE s1; __MIPS_REGISTER_TYPE s2; __MIPS_REGISTER_TYPE s3; __MIPS_REGISTER_TYPE s4; __MIPS_REGISTER_TYPE s5; __MIPS_REGISTER_TYPE s6; __MIPS_REGISTER_TYPE s7; __MIPS_REGISTER_TYPE sp; __MIPS_REGISTER_TYPE fp; __MIPS_REGISTER_TYPE ra; __MIPS_REGISTER_TYPE c0_sr; __MIPS_REGISTER_TYPE c0_epc; } Context_Control; /* WARNING: If this structure is modified, the constants in cpu.h * must also be updated. */ typedef struct { #if ( CPU_HARDWARE_FP == TRUE ) __MIPS_FPU_REGISTER_TYPE fp0; __MIPS_FPU_REGISTER_TYPE fp1; __MIPS_FPU_REGISTER_TYPE fp2; __MIPS_FPU_REGISTER_TYPE fp3; __MIPS_FPU_REGISTER_TYPE fp4; __MIPS_FPU_REGISTER_TYPE fp5; __MIPS_FPU_REGISTER_TYPE fp6; __MIPS_FPU_REGISTER_TYPE fp7; __MIPS_FPU_REGISTER_TYPE fp8; __MIPS_FPU_REGISTER_TYPE fp9; __MIPS_FPU_REGISTER_TYPE fp10; __MIPS_FPU_REGISTER_TYPE fp11; __MIPS_FPU_REGISTER_TYPE fp12; __MIPS_FPU_REGISTER_TYPE fp13; __MIPS_FPU_REGISTER_TYPE fp14; __MIPS_FPU_REGISTER_TYPE fp15; __MIPS_FPU_REGISTER_TYPE fp16; __MIPS_FPU_REGISTER_TYPE fp17; __MIPS_FPU_REGISTER_TYPE fp18; __MIPS_FPU_REGISTER_TYPE fp19; __MIPS_FPU_REGISTER_TYPE fp20; __MIPS_FPU_REGISTER_TYPE fp21; __MIPS_FPU_REGISTER_TYPE fp22; __MIPS_FPU_REGISTER_TYPE fp23; __MIPS_FPU_REGISTER_TYPE fp24; __MIPS_FPU_REGISTER_TYPE fp25; __MIPS_FPU_REGISTER_TYPE fp26; __MIPS_FPU_REGISTER_TYPE fp27; __MIPS_FPU_REGISTER_TYPE fp28; __MIPS_FPU_REGISTER_TYPE fp29; __MIPS_FPU_REGISTER_TYPE fp30; __MIPS_FPU_REGISTER_TYPE fp31; #endif } Context_Control_fp; /* * This struct reflects the stack frame employed in ISR_Handler. Note * that the ISR routine save some of the registers to this frame for * all interrupts and exceptions. Other registers are saved only on * exceptions, while others are not touched at all. The untouched * registers are not normally disturbed by high-level language * programs so they can be accessed when required. * * The registers and their ordering in this struct must directly * correspond to the layout and ordering of * shown in iregdef.h, * as cpu_asm.S uses those definitions to fill the stack frame. * This struct provides access to the stack frame for C code. * * Similarly, this structure is used by debugger stubs and exception * processing routines so be careful when changing the format. * * NOTE: The comments with this structure and cpu_asm.S should be kept * in sync. When in doubt, look in the code to see if the * registers you're interested in are actually treated as expected. * The order of the first portion of this structure follows the * order of registers expected by gdb. */ typedef struct { __MIPS_REGISTER_TYPE r0; /* 0 -- NOT FILLED IN */ __MIPS_REGISTER_TYPE at; /* 1 -- saved always */ __MIPS_REGISTER_TYPE v0; /* 2 -- saved always */ __MIPS_REGISTER_TYPE v1; /* 3 -- saved always */ __MIPS_REGISTER_TYPE a0; /* 4 -- saved always */ __MIPS_REGISTER_TYPE a1; /* 5 -- saved always */ __MIPS_REGISTER_TYPE a2; /* 6 -- saved always */ __MIPS_REGISTER_TYPE a3; /* 7 -- saved always */ __MIPS_REGISTER_TYPE t0; /* 8 -- saved always */ __MIPS_REGISTER_TYPE t1; /* 9 -- saved always */ __MIPS_REGISTER_TYPE t2; /* 10 -- saved always */ __MIPS_REGISTER_TYPE t3; /* 11 -- saved always */ __MIPS_REGISTER_TYPE t4; /* 12 -- saved always */ __MIPS_REGISTER_TYPE t5; /* 13 -- saved always */ __MIPS_REGISTER_TYPE t6; /* 14 -- saved always */ __MIPS_REGISTER_TYPE t7; /* 15 -- saved always */ __MIPS_REGISTER_TYPE s0; /* 16 -- saved on exceptions */ __MIPS_REGISTER_TYPE s1; /* 17 -- saved on exceptions */ __MIPS_REGISTER_TYPE s2; /* 18 -- saved on exceptions */ __MIPS_REGISTER_TYPE s3; /* 19 -- saved on exceptions */ __MIPS_REGISTER_TYPE s4; /* 20 -- saved on exceptions */ __MIPS_REGISTER_TYPE s5; /* 21 -- saved on exceptions */ __MIPS_REGISTER_TYPE s6; /* 22 -- saved on exceptions */ __MIPS_REGISTER_TYPE s7; /* 23 -- saved on exceptions */ __MIPS_REGISTER_TYPE t8; /* 24 -- saved always */ __MIPS_REGISTER_TYPE t9; /* 25 -- saved always */ __MIPS_REGISTER_TYPE k0; /* 26 -- NOT FILLED IN, kernel tmp reg */ __MIPS_REGISTER_TYPE k1; /* 27 -- NOT FILLED IN, kernel tmp reg */ __MIPS_REGISTER_TYPE gp; /* 28 -- saved always */ __MIPS_REGISTER_TYPE sp; /* 29 -- saved on exceptions NOT RESTORED */ __MIPS_REGISTER_TYPE fp; /* 30 -- saved always */ __MIPS_REGISTER_TYPE ra; /* 31 -- saved always */ __MIPS_REGISTER_TYPE c0_sr; /* 32 -- saved always, some bits are */ /* manipulated per-thread */ __MIPS_REGISTER_TYPE mdlo; /* 33 -- saved always */ __MIPS_REGISTER_TYPE mdhi; /* 34 -- saved always */ __MIPS_REGISTER_TYPE badvaddr; /* 35 -- saved on exceptions, read-only */ __MIPS_REGISTER_TYPE cause; /* 36 -- saved on exceptions NOT restored */ __MIPS_REGISTER_TYPE epc; /* 37 -- saved always, read-only register */ /* but logically restored */ __MIPS_FPU_REGISTER_TYPE f0; /* 38 -- saved if FP enabled */ __MIPS_FPU_REGISTER_TYPE f1; /* 39 -- saved if FP enabled */ __MIPS_FPU_REGISTER_TYPE f2; /* 40 -- saved if FP enabled */ __MIPS_FPU_REGISTER_TYPE f3; /* 41 -- saved if FP enabled */ __MIPS_FPU_REGISTER_TYPE f4; /* 42 -- saved if FP enabled */ __MIPS_FPU_REGISTER_TYPE f5; /* 43 -- saved if FP enabled */ __MIPS_FPU_REGISTER_TYPE f6; /* 44 -- saved if FP enabled */ __MIPS_FPU_REGISTER_TYPE f7; /* 45 -- saved if FP enabled */ __MIPS_FPU_REGISTER_TYPE f8; /* 46 -- saved if FP enabled */ __MIPS_FPU_REGISTER_TYPE f9; /* 47 -- saved if FP enabled */ __MIPS_FPU_REGISTER_TYPE f10; /* 48 -- saved if FP enabled */ __MIPS_FPU_REGISTER_TYPE f11; /* 49 -- saved if FP enabled */ __MIPS_FPU_REGISTER_TYPE f12; /* 50 -- saved if FP enabled */ __MIPS_FPU_REGISTER_TYPE f13; /* 51 -- saved if FP enabled */ __MIPS_FPU_REGISTER_TYPE f14; /* 52 -- saved if FP enabled */ __MIPS_FPU_REGISTER_TYPE f15; /* 53 -- saved if FP enabled */ __MIPS_FPU_REGISTER_TYPE f16; /* 54 -- saved if FP enabled */ __MIPS_FPU_REGISTER_TYPE f17; /* 55 -- saved if FP enabled */ __MIPS_FPU_REGISTER_TYPE f18; /* 56 -- saved if FP enabled */ __MIPS_FPU_REGISTER_TYPE f19; /* 57 -- saved if FP enabled */ __MIPS_FPU_REGISTER_TYPE f20; /* 58 -- saved if FP enabled */ __MIPS_FPU_REGISTER_TYPE f21; /* 59 -- saved if FP enabled */ __MIPS_FPU_REGISTER_TYPE f22; /* 60 -- saved if FP enabled */ __MIPS_FPU_REGISTER_TYPE f23; /* 61 -- saved if FP enabled */ __MIPS_FPU_REGISTER_TYPE f24; /* 62 -- saved if FP enabled */ __MIPS_FPU_REGISTER_TYPE f25; /* 63 -- saved if FP enabled */ __MIPS_FPU_REGISTER_TYPE f26; /* 64 -- saved if FP enabled */ __MIPS_FPU_REGISTER_TYPE f27; /* 65 -- saved if FP enabled */ __MIPS_FPU_REGISTER_TYPE f28; /* 66 -- saved if FP enabled */ __MIPS_FPU_REGISTER_TYPE f29; /* 67 -- saved if FP enabled */ __MIPS_FPU_REGISTER_TYPE f30; /* 68 -- saved if FP enabled */ __MIPS_FPU_REGISTER_TYPE f31; /* 69 -- saved if FP enabled */ __MIPS_REGISTER_TYPE fcsr; /* 70 -- saved on exceptions */ /* (oddly not documented on MGV) */ __MIPS_REGISTER_TYPE feir; /* 71 -- saved on exceptions */ /* (oddly not documented on MGV) */ /* GDB does not seem to care about anything past this point */ __MIPS_REGISTER_TYPE tlbhi; /* 72 - NOT FILLED IN, doesn't exist on */ /* all MIPS CPUs (at least MGV) */ #if __mips == 1 __MIPS_REGISTER_TYPE tlblo; /* 73 - NOT FILLED IN, doesn't exist on */ /* all MIPS CPUs (at least MGV) */ #endif #if __mips == 3 __MIPS_REGISTER_TYPE tlblo0; /* 73 - NOT FILLED IN, doesn't exist on */ /* all MIPS CPUs (at least MGV) */ #endif __MIPS_REGISTER_TYPE inx; /* 74 -- NOT FILLED IN, doesn't exist on */ /* all MIPS CPUs (at least MGV) */ __MIPS_REGISTER_TYPE rand; /* 75 -- NOT FILLED IN, doesn't exist on */ /* all MIPS CPUs (at least MGV) */ __MIPS_REGISTER_TYPE ctxt; /* 76 -- NOT FILLED IN, doesn't exist on */ /* all MIPS CPUs (at least MGV) */ __MIPS_REGISTER_TYPE exctype; /* 77 -- NOT FILLED IN (not enough info) */ __MIPS_REGISTER_TYPE mode; /* 78 -- NOT FILLED IN (not enough info) */ __MIPS_REGISTER_TYPE prid; /* 79 -- NOT FILLED IN (not need to do so) */ __MIPS_REGISTER_TYPE tar ; /* 80 -- target address register, filled on exceptions */ /* end of __mips == 1 so NREGS == 81 */ #if __mips == 3 __MIPS_REGISTER_TYPE tlblo1; /* 81 -- NOT FILLED IN */ __MIPS_REGISTER_TYPE pagemask; /* 82 -- NOT FILLED IN */ __MIPS_REGISTER_TYPE wired; /* 83 -- NOT FILLED IN */ __MIPS_REGISTER_TYPE count; /* 84 -- NOT FILLED IN */ __MIPS_REGISTER_TYPE compare; /* 85 -- NOT FILLED IN */ __MIPS_REGISTER_TYPE config; /* 86 -- NOT FILLED IN */ __MIPS_REGISTER_TYPE lladdr; /* 87 -- NOT FILLED IN */ __MIPS_REGISTER_TYPE watchlo; /* 88 -- NOT FILLED IN */ __MIPS_REGISTER_TYPE watchhi; /* 89 -- NOT FILLED IN */ __MIPS_REGISTER_TYPE ecc; /* 90 -- NOT FILLED IN */ __MIPS_REGISTER_TYPE cacheerr; /* 91 -- NOT FILLED IN */ __MIPS_REGISTER_TYPE taglo; /* 92 -- NOT FILLED IN */ __MIPS_REGISTER_TYPE taghi; /* 93 -- NOT FILLED IN */ __MIPS_REGISTER_TYPE errpc; /* 94 -- NOT FILLED IN */ __MIPS_REGISTER_TYPE xctxt; /* 95 -- NOT FILLED IN */ /* end of __mips == 3 so NREGS == 96 */ #endif } CPU_Interrupt_frame; /* * The following table contains the information required to configure * the mips processor specific parameters. */ typedef struct { void (*pretasking_hook)( void ); void (*predriver_hook)( void ); void (*postdriver_hook)( void ); void (*idle_task)( void ); boolean do_zero_of_workspace; unsigned32 idle_task_stack_size; unsigned32 interrupt_stack_size; unsigned32 extra_mpci_receive_server_stack; void * (*stack_allocate_hook)( unsigned32 ); void (*stack_free_hook)( void* ); /* end of fields required on all CPUs */ unsigned32 clicks_per_microsecond; } rtems_cpu_table; /* * Macros to access required entires in the CPU Table are in * the file rtems/system.h. */ /* * Macros to access MIPS specific additions to the CPU Table */ #define rtems_cpu_configuration_get_clicks_per_microsecond() \ (_CPU_Table.clicks_per_microsecond) /* * This variable is optional. It is used on CPUs on which it is difficult * to generate an "uninitialized" FP context. It is filled in by * _CPU_Initialize and copied into the task's FP context area during * _CPU_Context_Initialize. */ SCORE_EXTERN Context_Control_fp _CPU_Null_fp_context; /* * On some CPUs, RTEMS supports a software managed interrupt stack. * This stack is allocated by the Interrupt Manager and the switch * is performed in _ISR_Handler. These variables contain pointers * to the lowest and highest addresses in the chunk of memory allocated * for the interrupt stack. Since it is unknown whether the stack * grows up or down (in general), this give the CPU dependent * code the option of picking the version it wants to use. * * NOTE: These two variables are required if the macro * CPU_HAS_SOFTWARE_INTERRUPT_STACK is defined as TRUE. */ SCORE_EXTERN void *_CPU_Interrupt_stack_low; SCORE_EXTERN void *_CPU_Interrupt_stack_high; /* * With some compilation systems, it is difficult if not impossible to * call a high-level language routine from assembly language. This * is especially true of commercial Ada compilers and name mangling * C++ ones. This variable can be optionally defined by the CPU porter * and contains the address of the routine _Thread_Dispatch. This * can make it easier to invoke that routine at the end of the interrupt * sequence (if a dispatch is necessary). * SCORE_EXTERN void (*_CPU_Thread_dispatch_pointer)(); * * NOTE: Not needed on this port. */ /* * Nothing prevents the porter from declaring more CPU specific variables. */ /* XXX: if needed, put more variables here */ /* * The size of the floating point context area. On some CPUs this * will not be a "sizeof" because the format of the floating point * area is not defined -- only the size is. This is usually on * CPUs with a "floating point save context" instruction. */ #define CPU_CONTEXT_FP_SIZE sizeof( Context_Control_fp ) /* * Amount of extra stack (above minimum stack size) required by * system initialization thread. Remember that in a multiprocessor * system the system intialization thread becomes the MP server thread. */ #define CPU_MPCI_RECEIVE_SERVER_EXTRA_STACK 0 /* * This defines the number of entries in the ISR_Vector_table managed * by RTEMS. */ extern unsigned int mips_interrupt_number_of_vectors; #define CPU_INTERRUPT_NUMBER_OF_VECTORS (mips_interrupt_number_of_vectors) #define CPU_INTERRUPT_MAXIMUM_VECTOR_NUMBER (CPU_INTERRUPT_NUMBER_OF_VECTORS - 1) /* * Should be large enough to run all RTEMS tests. This insures * that a "reasonable" small application should not have any problems. */ #define CPU_STACK_MINIMUM_SIZE (2048*sizeof(unsigned32)) /* * CPU's worst alignment requirement for data types on a byte boundary. This * alignment does not take into account the requirements for the stack. */ #define CPU_ALIGNMENT 8 /* * This number corresponds to the byte alignment requirement for the * heap handler. This alignment requirement may be stricter than that * for the data types alignment specified by CPU_ALIGNMENT. It is * common for the heap to follow the same alignment requirement as * CPU_ALIGNMENT. If the CPU_ALIGNMENT is strict enough for the heap, * then this should be set to CPU_ALIGNMENT. * * NOTE: This does not have to be a power of 2. It does have to * be greater or equal to than CPU_ALIGNMENT. */ #define CPU_HEAP_ALIGNMENT CPU_ALIGNMENT /* * This number corresponds to the byte alignment requirement for memory * buffers allocated by the partition manager. This alignment requirement * may be stricter than that for the data types alignment specified by * CPU_ALIGNMENT. It is common for the partition to follow the same * alignment requirement as CPU_ALIGNMENT. If the CPU_ALIGNMENT is strict * enough for the partition, then this should be set to CPU_ALIGNMENT. * * NOTE: This does not have to be a power of 2. It does have to * be greater or equal to than CPU_ALIGNMENT. */ #define CPU_PARTITION_ALIGNMENT CPU_ALIGNMENT /* * This number corresponds to the byte alignment requirement for the * stack. This alignment requirement may be stricter than that for the * data types alignment specified by CPU_ALIGNMENT. If the CPU_ALIGNMENT * is strict enough for the stack, then this should be set to 0. * * NOTE: This must be a power of 2 either 0 or greater than CPU_ALIGNMENT. */ #define CPU_STACK_ALIGNMENT CPU_ALIGNMENT /* * ISR handler macros */ /* * Support routine to initialize the RTEMS vector table after it is allocated. */ #define _CPU_Initialize_vectors() /* * Disable all interrupts for an RTEMS critical section. The previous * level is returned in _level. */ #define _CPU_ISR_Disable( _level ) \ do { \ unsigned int _scratch; \ mips_get_sr( _scratch ); \ mips_set_sr( _scratch & ~SR_INTERRUPT_ENABLE_BITS ); \ _level = _scratch & SR_INTERRUPT_ENABLE_BITS; \ } while(0) /* * Enable interrupts to the previous level (returned by _CPU_ISR_Disable). * This indicates the end of an RTEMS critical section. The parameter * _level is not modified. */ #define _CPU_ISR_Enable( _level ) \ do { \ unsigned int _scratch; \ mips_get_sr( _scratch ); \ mips_set_sr( (_scratch & ~SR_INTERRUPT_ENABLE_BITS) | (_level & SR_INTERRUPT_ENABLE_BITS) ); \ } while(0) /* * This temporarily restores the interrupt to _level before immediately * disabling them again. This is used to divide long RTEMS critical * sections into two or more parts. The parameter _level is not * modified. */ #define _CPU_ISR_Flash( _xlevel ) \ do { \ unsigned int _scratch2 = _xlevel; \ _CPU_ISR_Enable( _scratch2 ); \ _CPU_ISR_Disable( _scratch2 ); \ _xlevel = _scratch2; \ } while(0) /* * Map interrupt level in task mode onto the hardware that the CPU * actually provides. Currently, interrupt levels which do not * map onto the CPU in a generic fashion are undefined. Someday, * it would be nice if these were "mapped" by the application * via a callout. For example, m68k has 8 levels 0 - 7, levels * 8 - 255 would be available for bsp/application specific meaning. * This could be used to manage a programmable interrupt controller * via the rtems_task_mode directive. * * On the MIPS, 0 is all on. Non-zero is all off. This only * manipulates the IEC. */ unsigned32 _CPU_ISR_Get_level( void ); /* in cpu.c */ void _CPU_ISR_Set_level( unsigned32 ); /* in cpu.c */ /* end of ISR handler macros */ /* Context handler macros */ /* * Initialize the context to a state suitable for starting a * task after a context restore operation. Generally, this * involves: * * - setting a starting address * - preparing the stack * - preparing the stack and frame pointers * - setting the proper interrupt level in the context * - initializing the floating point context * * This routine generally does not set any unnecessary register * in the context. The state of the "general data" registers is * undefined at task start time. * * NOTE: This is_fp parameter is TRUE if the thread is to be a floating * point thread. This is typically only used on CPUs where the * FPU may be easily disabled by software such as on the SPARC * where the PSR contains an enable FPU bit. * * The per-thread status register holds the interrupt enable, FP enable * and global interrupt enable for that thread. It means each thread can * enable its own set of interrupts. If interrupts are disabled, RTEMS * can still dispatch via blocking calls. This is the function of the * "Interrupt Level", and on the MIPS, it controls the IEC bit and all * the hardware interrupts as defined in the SR. Software ints * are automatically enabled for all threads, as they will only occur under * program control anyhow. Besides, the interrupt level parm is only 8 bits, * and controlling the software ints plus the others would require 9. * * If the Interrupt Level is 0, all ints are on. Otherwise, the * Interrupt Level should supply a bit pattern to impose on the SR * interrupt bits; bit 0 applies to the mips1 IEC bit/mips3 EXL&IE, bits 1 thru 6 * apply to the SR register Intr bits from bit 10 thru bit 15. Bit 7 of * the Interrupt Level parameter is unused at this time. * * These are the only per-thread SR bits, the others are maintained * globally & explicitly preserved by the Context Switch code in cpu_asm.s */ #if __mips == 3 #define _INTON (SR_EXL | SR_IE) #define _EXTRABITS 0 #endif #if __mips == 1 #define _INTON SR_IEC #define _EXTRABITS 0 /* make sure we're in user mode on MIPS1 processors */ #endif #define _CPU_Context_Initialize( _the_context, _stack_base, _size, _isr, _entry_point, _is_fp ) \ { \ unsigned32 _stack_tmp = \ (unsigned32)(_stack_base) + (_size) - CPU_STACK_ALIGNMENT; \ unsigned32 _intlvl = _isr & 0xff; \ _stack_tmp &= ~(CPU_STACK_ALIGNMENT - 1); \ (_the_context)->sp = _stack_tmp; \ (_the_context)->fp = _stack_tmp; \ (_the_context)->ra = (unsigned64)_entry_point; \ (_the_context)->c0_sr = ((_intlvl==0)?(0xFF00 | _INTON):( ((_intlvl<<9) & 0xfc00) | \ 0x300 | \ ((_intlvl & 1)?_INTON:0)) ) | \ SR_CU0 | ((_is_fp)?SR_CU1:0) | _EXTRABITS; \ } /* * This routine is responsible for somehow restarting the currently * executing task. If you are lucky, then all that is necessary * is restoring the context. Otherwise, there will need to be * a special assembly routine which does something special in this * case. Context_Restore should work most of the time. It will * not work if restarting self conflicts with the stack frame * assumptions of restoring a context. */ #define _CPU_Context_Restart_self( _the_context ) \ _CPU_Context_restore( (_the_context) ); /* * The purpose of this macro is to allow the initial pointer into * A floating point context area (used to save the floating point * context) to be at an arbitrary place in the floating point * context area. * * This is necessary because some FP units are designed to have * their context saved as a stack which grows into lower addresses. * Other FP units can be saved by simply moving registers into offsets * from the base of the context area. Finally some FP units provide * a "dump context" instruction which could fill in from high to low * or low to high based on the whim of the CPU designers. */ #define _CPU_Context_Fp_start( _base, _offset ) \ ( (void *) _Addresses_Add_offset( (_base), (_offset) ) ) /* * This routine initializes the FP context area passed to it to. * There are a few standard ways in which to initialize the * floating point context. The code included for this macro assumes * that this is a CPU in which a "initial" FP context was saved into * _CPU_Null_fp_context and it simply copies it to the destination * context passed to it. * * Other models include (1) not doing anything, and (2) putting * a "null FP status word" in the correct place in the FP context. */ #if ( CPU_HARDWARE_FP == TRUE ) #define _CPU_Context_Initialize_fp( _destination ) \ { \ *((Context_Control_fp *) *((void **) _destination)) = _CPU_Null_fp_context; \ } #endif /* end of Context handler macros */ /* Fatal Error manager macros */ /* * This routine copies _error into a known place -- typically a stack * location or a register, optionally disables interrupts, and * halts/stops the CPU. */ #define _CPU_Fatal_halt( _error ) \ do { \ unsigned int _level; \ _CPU_ISR_Disable(_level); \ loop: goto loop; \ } while (0) extern void mips_break( int error ); /* Bitfield handler macros */ /* * This routine sets _output to the bit number of the first bit * set in _value. _value is of CPU dependent type Priority_Bit_map_control. * This type may be either 16 or 32 bits wide although only the 16 * least significant bits will be used. * * There are a number of variables in using a "find first bit" type * instruction. * * (1) What happens when run on a value of zero? * (2) Bits may be numbered from MSB to LSB or vice-versa. * (3) The numbering may be zero or one based. * (4) The "find first bit" instruction may search from MSB or LSB. * * RTEMS guarantees that (1) will never happen so it is not a concern. * (2),(3), (4) are handled by the macros _CPU_Priority_mask() and * _CPU_Priority_bits_index(). These three form a set of routines * which must logically operate together. Bits in the _value are * set and cleared based on masks built by _CPU_Priority_mask(). * The basic major and minor values calculated by _Priority_Major() * and _Priority_Minor() are "massaged" by _CPU_Priority_bits_index() * to properly range between the values returned by the "find first bit" * instruction. This makes it possible for _Priority_Get_highest() to * calculate the major and directly index into the minor table. * This mapping is necessary to ensure that 0 (a high priority major/minor) * is the first bit found. * * This entire "find first bit" and mapping process depends heavily * on the manner in which a priority is broken into a major and minor * components with the major being the 4 MSB of a priority and minor * the 4 LSB. Thus (0 << 4) + 0 corresponds to priority 0 -- the highest * priority. And (15 << 4) + 14 corresponds to priority 254 -- the next * to the lowest priority. * * If your CPU does not have a "find first bit" instruction, then * there are ways to make do without it. Here are a handful of ways * to implement this in software: * * - a series of 16 bit test instructions * - a "binary search using if's" * - _number = 0 * if _value > 0x00ff * _value >>=8 * _number = 8; * * if _value > 0x0000f * _value >=8 * _number += 4 * * _number += bit_set_table[ _value ] * * where bit_set_table[ 16 ] has values which indicate the first * bit set */ #define CPU_USE_GENERIC_BITFIELD_CODE TRUE #define CPU_USE_GENERIC_BITFIELD_DATA TRUE #if (CPU_USE_GENERIC_BITFIELD_CODE == FALSE) #define _CPU_Bitfield_Find_first_bit( _value, _output ) \ { \ (_output) = 0; /* do something to prevent warnings */ \ } #endif /* end of Bitfield handler macros */ /* * This routine builds the mask which corresponds to the bit fields * as searched by _CPU_Bitfield_Find_first_bit(). See the discussion * for that routine. */ #if (CPU_USE_GENERIC_BITFIELD_CODE == FALSE) #define _CPU_Priority_Mask( _bit_number ) \ ( 1 << (_bit_number) ) #endif /* * This routine translates the bit numbers returned by * _CPU_Bitfield_Find_first_bit() into something suitable for use as * a major or minor component of a priority. See the discussion * for that routine. */ #if (CPU_USE_GENERIC_BITFIELD_CODE == FALSE) #define _CPU_Priority_bits_index( _priority ) \ (_priority) #endif /* end of Priority handler macros */ /* functions */ /* * _CPU_Initialize * * This routine performs CPU dependent initialization. */ void _CPU_Initialize( rtems_cpu_table *cpu_table, void (*thread_dispatch) ); /* * _CPU_ISR_install_raw_handler * * This routine installs a "raw" interrupt handler directly into the * processor's vector table. */ void _CPU_ISR_install_raw_handler( unsigned32 vector, proc_ptr new_handler, proc_ptr *old_handler ); /* * _CPU_ISR_install_vector * * This routine installs an interrupt vector. */ void _CPU_ISR_install_vector( unsigned32 vector, proc_ptr new_handler, proc_ptr *old_handler ); /* * _CPU_Install_interrupt_stack * * This routine installs the hardware interrupt stack pointer. * * NOTE: It need only be provided if CPU_HAS_HARDWARE_INTERRUPT_STACK * is TRUE. */ void _CPU_Install_interrupt_stack( void ); /* * _CPU_Internal_threads_Idle_thread_body * * This routine is the CPU dependent IDLE thread body. * * NOTE: It need only be provided if CPU_PROVIDES_IDLE_THREAD_BODY * is TRUE. */ void _CPU_Thread_Idle_body( void ); /* * _CPU_Context_switch * * This routine switches from the run context to the heir context. */ void _CPU_Context_switch( Context_Control *run, Context_Control *heir ); /* * _CPU_Context_restore * * This routine is generally used only to restart self in an * efficient manner. It may simply be a label in _CPU_Context_switch. * * NOTE: May be unnecessary to reload some registers. */ void _CPU_Context_restore( Context_Control *new_context ); /* * _CPU_Context_save_fp * * This routine saves the floating point context passed to it. */ void _CPU_Context_save_fp( void **fp_context_ptr ); /* * _CPU_Context_restore_fp * * This routine restores the floating point context passed to it. */ void _CPU_Context_restore_fp( void **fp_context_ptr ); /* The following routine swaps the endian format of an unsigned int. * It must be static because it is referenced indirectly. * * This version will work on any processor, but if there is a better * way for your CPU PLEASE use it. The most common way to do this is to: * * swap least significant two bytes with 16-bit rotate * swap upper and lower 16-bits * swap most significant two bytes with 16-bit rotate * * Some CPUs have special instructions which swap a 32-bit quantity in * a single instruction (e.g. i486). It is probably best to avoid * an "endian swapping control bit" in the CPU. One good reason is * that interrupts would probably have to be disabled to insure that * an interrupt does not try to access the same "chunk" with the wrong * endian. Another good reason is that on some CPUs, the endian bit * endianness for ALL fetches -- both code and data -- so the code * will be fetched incorrectly. */ static inline unsigned int CPU_swap_u32( unsigned int value ) { unsigned32 byte1, byte2, byte3, byte4, swapped; byte4 = (value >> 24) & 0xff; byte3 = (value >> 16) & 0xff; byte2 = (value >> 8) & 0xff; byte1 = value & 0xff; swapped = (byte1 << 24) | (byte2 << 16) | (byte3 << 8) | byte4; return( swapped ); } #define CPU_swap_u16( value ) \ (((value&0xff) << 8) | ((value >> 8)&0xff)) #endif #ifdef __cplusplus } #endif #endif