arch.inc

开放源码实时操作系统源码.

#ifndef CYGONCE_HAL_ARCH_INC
#define CYGONCE_HAL_ARCH_INC
##=============================================================================
##
##	arch.inc
##
##	MIPS assembler header file
##
##=============================================================================
#####ECOSGPLCOPYRIGHTBEGIN####
## -------------------------------------------
## This file is part of eCos, the Embedded Configurable Operating System.
## Copyright (C) 1998, 1999, 2000, 2001, 2002 Red Hat, Inc.
##
## eCos is free software; you can redistribute it and/or modify it under
## the terms of the GNU General Public License as published by the Free
## Software Foundation; either version 2 or (at your option) any later version.
##
## eCos is distributed in the hope that it will be useful, but WITHOUT ANY
## WARRANTY; without even the implied warranty of MERCHANTABILITY or
## FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
## for more details.
##
## You should have received a copy of the GNU General Public License along
## with eCos; if not, write to the Free Software Foundation, Inc.,
## 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
##
## As a special exception, if other files instantiate templates or use macros
## or inline functions from this file, or you compile this file and link it
## with other works to produce a work based on this file, this file does not
## by itself cause the resulting work to be covered by the GNU General Public
## License. However the source code for this file must still be made available
## in accordance with section (3) of the GNU General Public License.
##
## This exception does not invalidate any other reasons why a work based on
## this file might be covered by the GNU General Public License.
##
## Alternative licenses for eCos may be arranged by contacting Red Hat, Inc.
## at http://sources.redhat.com/ecos/ecos-license/
## -------------------------------------------
#####ECOSGPLCOPYRIGHTEND####
##=============================================================================
#######DESCRIPTIONBEGIN####
##
## Author(s): 	nickg
## Contributors:	nickg, dmoseley
## Date:	1997-10-16
## Purpose:	Architecture definitions.
## Description:	This file contains various definitions and macros that are
##              useful for writing assembly code for the MIPS CPU family.
## Usage:
##		#include <cyg/hal/arch.inc>
##		...
##		
##
######DESCRIPTIONEND####
##
##=============================================================================

#include <cyg/hal/mips.inc>
	
#include <cyg/hal/variant.inc>

##-----------------------------------------------------------------------------	
## Set up the value for the initial status register


# Either the variant or platform may define an INITIAL_SR of its
#own. If not then provide a default value here.

#ifndef INITIAL_SR

# Both the variant and platform HALs have the option to add some bits
# to the default status register. If they do not choose to do so,
# supply default zeroes here.

# ifndef INITIAL_SR_VAR
#  define INITIAL_SR_VAR 0x00000000
# endif
# ifndef INITIAL_SR_PLF
#  define INITIAL_SR_PLF 0x00000000
# endif

#if defined(CYG_HAL_STARTUP_RAM) || defined(CYG_HAL_STARTUP_ROMRAM)
# if defined(CYGPKG_HAL_MIPS_SIM) || !defined(CYGSEM_HAL_USE_ROM_MONITOR)
#  define INITIAL_SR_ARCH 	0x1000ff00 /* CP0 usable, Ints enabled, master interrupt disable */
# else
#  define INITIAL_SR_ARCH 	0x1040ff00	/* as above + ROM vectors used	*/
# endif	
#elif defined(CYG_HAL_STARTUP_ROM)
# define INITIAL_SR_ARCH	0x1040ff00	/* as above + ROM vectors used	*/
#endif

#define INITIAL_SR 	(INITIAL_SR_ARCH|INITIAL_SR_VAR|INITIAL_SR_PLF)

#endif

##-----------------------------------------------------------------------------
## Setup the initial value for the config0 register

#ifndef INITIAL_CONFIG0

#define	INITIAL_CONFIG0	0x00000002

#endif

##-----------------------------------------------------------------------------
## MIPS thread and interrupt saved state. This must match the layout of the
## HAL_SavedRegisters in hal_arch.h. Do not change this without changing the
## layout there, or viceversa.	

# Size of registers that change size between 32 and 64 bit implementations
#ifdef CYGHWR_HAL_MIPS_64BIT
# define mips_regsize 	8
#else
# define mips_regsize 	4
#endif

# Size of registers that stay the same size in all implementations
# define mips_regsize32	4

# Size of FPU registers.
#if defined(CYGHWR_HAL_MIPS_FPU)
# if defined(CYGHWR_HAL_MIPS_FPU_64BIT)
#  define mips_fpuregsize 8
# elif defined(CYGHWR_HAL_MIPS_FPU_32BIT)
#  define mips_fpuregsize 4
# else
#  error MIPS FPU register size not defined
# endif
#endif


#define	mipsreg_regs	0
#define	mipsreg_hi	(mips_regsize*32)
#define	mipsreg_lo	(mipsreg_hi+mips_regsize)
#ifdef CYGHWR_HAL_MIPS_FPU
# define mipsreg_fpureg	(mipsreg_lo+mips_regsize)
# define mipsreg_fcr31	(mipsreg_fpureg+(mips_fpuregsize*32))
# define mipsreg_fppad  (mipsreg_fcr31+mips_regsize32)
# define mipsreg_vector	(mipsreg_fppad+mips_regsize32)
#else
# define mipsreg_vector	(mipsreg_lo+mips_regsize)
#endif
#define	mipsreg_sr	(mipsreg_vector+mips_regsize32)
#define	mipsreg_pc	(mipsreg_sr+mips_regsize32)
#define	mipsreg_cachectrl (mipsreg_pc+mips_regsize)
#define	mipsreg_cause	(mipsreg_cachectrl+mips_regsize32)
#define	mipsreg_badvr	(mipsreg_cause+mips_regsize32)
#define	mipsreg_prid	(mipsreg_badvr+mips_regsize)
#define	mipsreg_config	(mipsreg_prid+mips_regsize32)
#define	mipsreg_size	(mipsreg_config+mips_regsize32)

# The following expression ensures that the decrement is always a
# multiple of 16 bytes. This is a requirement of the MEABI used in
# MIPS32/64 targets.

#define mips_exception_decrement	((mipsreg_size*2)&~0xF)

##-----------------------------------------------------------------------------
## Minimal stack frame size uses to call functions from asm.
	
#define mips_stack_frame_size		32	// 4 (64 bit) args worth

##-----------------------------------------------------------------------------
## Load Address and Relocate. This macro is used in code that may be linked
## to execute out of RAM but is actually executed from ROM. If that is the
## case a suitable version of this macro will have been defined elsewhere.
## This is just a default version for use when that does not happen.

#ifndef CYGPKG_HAL_MIPS_LAR_DEFINED

	.macro	lar	reg,addr
	la	\reg,\addr
	.endm

#define CYGPKG_HAL_MIPS_LAR_DEFINED

#endif

##-----------------------------------------------------------------------------
## CPU specific macros. These provide a common assembler interface to
## operations that may have CPU specific implementations on different
## variants of the architecture.		
	
	# Initialize CPU
	.macro	hal_cpu_init

#if defined(CYGPKG_HAL_MIPS_MIPS32) || defined(CYGPKG_HAL_MIPS_MIPS64)
	# Initialize/clear watchpoint registers
	mvatc0	zero, C0_WATCHLO
	nop
	nop
	nop
	mtc0	zero, C0_WATCHHI 
	nop
	nop
	nop
#endif /* CYGPKG_HAL_MIPS_MIPS32 || CYGPKG_HAL_MIPS_MIPS64 */
	mtc0	zero,cause		# zero cause reg
	nop
#if !defined(CYGSEM_HAL_USE_ROM_MONITOR)
	la	v0,INITIAL_SR 		# initialize status register
	mtc0	v0,status
	nop
	nop
	nop
	la	v0,INITIAL_CONFIG0
	mtc0	v0,config0
	nop
	nop
	nop
#endif
	.endm

	# Enable interrupts
#ifdef CYG_HAL_MIPS_R3900	
	.macro hal_cpu_int_enable
	mfc0	v0,status
	nop
	nop
	ori	v0,v0,0x0001		# set IE bit
	mtc0	v0,status
	nop
	nop
	nop
	.endm		
#else
	.macro hal_cpu_int_enable	
	mfc0	v0,status
	la	v1,0xFFFFFFF9
	and	v0,v0,v1		# clear EXL and ERL bits	
	ori	v0,v0,0x0001		# set IE bit
	mtc0	v0,status
	nop
	nop
	nop	
	.endm	
#endif		


	# Disable interrupts
	.macro hal_cpu_int_disable
	mfc0	v0,status
	la	v1,0xFFFFFFFE
	and	v0,v0,v1
	mtc0	v0,status
	nop
	nop
	nop
	.endm	

	# Merge the interrupt enable state of the status register in
	# \sr with the current sr.
#ifdef CYG_HAL_MIPS_R3900
#define HAL_SR_INT_MASK	0x00000001		// IEc only
#else
#define HAL_SR_INT_MASK	0x00000007		// IE, EXL, ERL
#endif			
	.macro	hal_cpu_int_merge sr
	mfc0	v0,status			# V0 = current SR
	la	v1,HAL_SR_INT_MASK		# V1 = SR interrupt bits mask
	and	\sr,\sr,v1			# Isolate interrupt bits of \sr
	nor	v1,v1,zero			# Invert mask
	and	v0,v0,v1			# V0 = current SR except int bits
	or	v0,v0,\sr			# V0 = New SR
	mtc0	v0,status			# Return to SR
	.endm

	# Enable further exception processing, and disable
	# interrupt processing.
#ifdef CYG_HAL_MIPS_R3900	
	.macro hal_cpu_except_enable
	hal_cpu_int_disable
	.endm		
#else
	.macro hal_cpu_except_enable
	mfc0	v0,status
	la	v1,0xFFFFFFF0
	and	v0,v0,v1		# clear EXL, ERL and IE bits	
	mtc0	v0,status
	nop
	nop
	nop
	.endm
#endif		
	
	# Return from exception.
#ifdef CYG_HAL_MIPS_R3900
	.macro	hal_cpu_eret pc,sr
	mtc0	\sr,status			# Load status register
	nop
	nop
	nop
	sync					# settle things down
	jr	\pc				# jump back to interrupted code
	rfe					# restore state	(delay slot)	
	.endm
#else
	.macro	hal_cpu_eret pc,sr
        .set mips3
	ori     \sr,\sr,2                       # prevent interrupts until eret
	mtc0	\sr,status			# put SR back
	nop
	nop
	nop
	mvatc0	\pc,epc				# put PC in EPC
	nop
	nop
	nop
	sync					# settle things down
	eret					# return
	nop					# just to be safe
        .set mips0
	.endm
#endif	
	
##-----------------------------------------------------------------------------
# Default MIPS interrupt decoding macros. This uses the basic interrupt
# support provided by CP0 in the cause and status registers. If there is
# a more complex external interrupt controller, or the default stuff is
# interpreted differently (as in the TX3904) then these macros will be 
# overridden and CYGPKG_HAL_MIPS_INTC_DEFINED will be defined.

#ifndef CYGPKG_HAL_MIPS_INTC_DEFINED

#ifndef CYGPKG_HAL_MIPS_INTC_INIT_DEFINED
	# initialize all interrupts to disabled
	.macro	hal_intc_init
	mfc0	v0,status
	nop
	lui	v1,0xFFFF
	ori	v1,v1,0x00FF
	and	v0,v0,v1		# clear the IntMask bits
	mtc0	v0,status
	nop
	nop
	nop
	.endm
#endif

#ifndef CYGPKG_HAL_MIPS_INTC_DECODE_DEFINED
	.macro	hal_intc_decode vnum
	mfc0	v1,status		# get status register (interrupt mask)
	nop				# delay slot
	mfc0	v0,cause		# get cause register
	nop				# delay slot
	and	v0,v0,v1		# apply interrupt mask
	srl	v0,v0,10		# shift interrupt bits down
	andi	v0,v0,0x3f		# isolate 6 interrupt bits
	la	v1,hal_intc_translation_table
	add	v0,v0,v1		# index into table
	lb	\vnum,0(v0)		# pick up vector number
	.endm
#endif

#ifndef CYGPKG_HAL_MIPS_INTC_TRANSLATE_DEFINED
#ifdef CYGIMP_HAL_COMMON_INTERRUPTS_CHAIN
	.macro	hal_intc_translate inum,vnum
	move	\vnum,zero			# Just vector zero is supported
	.endm
#else			
	.macro	hal_intc_translate inum,vnum
	move	\vnum,\inum			# Vector == interrupt number
	.endm
#endif
#endif

	.macro	hal_intc_decode_data
hal_intc_translation_table:	
	.byte	0, 0, 1, 0
	.byte	2, 0, 1, 0
	.byte	3, 0, 1, 0
	.byte	2, 0, 1, 0
	.byte	4, 0, 1, 0
	.byte	2, 0, 1, 0
	.byte	3, 0, 1, 0
	.byte	2, 0, 1, 0
	.byte	5, 0, 1, 0
	.byte	2, 0, 1, 0
	.byte	3, 0, 1, 0
	.byte	2, 0, 1, 0
	.byte	4, 0, 1, 0
	.byte	2, 0, 1, 0
	.byte	3, 0, 1, 0
	.byte	2, 0, 1, 0
	.endm
#endif

#------------------------------------------------------------------------------