variant.inc

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#ifndef CYGONCE_HAL_VARIANT_INC
#define CYGONCE_HAL_VARIANT_INC
##=============================================================================
##
##      variant.inc
##
##      RM7000 family 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.
##
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## 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.
##
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## 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
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## 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.
##
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## -------------------------------------------
#####ECOSGPLCOPYRIGHTEND####
##=============================================================================
#######DESCRIPTIONBEGIN####
##
## Author(s):   nickg
## Contributors:nickg, jskov
## Date:        2000-05-10
## Purpose:     RM7000 family definitions.
## Description: This file contains various definitions and macros that are
##              useful for writing assembly code for the RM7000 CPU family.
## Usage:
##              #include <cyg/hal/variant.inc>
##              ...
##              
##
######DESCRIPTIONEND####
##
##=============================================================================

#include <pkgconf/hal.h>
        
#include <cyg/hal/mips.inc>
#include <cyg/hal/platform.inc>
#include <cyg/hal/var_defs.inc>

##-----------------------------------------------------------------------------
## Define CPU variant for architecture HAL.
                        
#define CYG_HAL_MIPS_RM7000

#------------------------------------------------------------------------------
# Set up initial value for config register. Sets endian mode and
# disables the cache on kseg0.

#if defined(CYGPKG_HAL_MIPS_MSBFIRST)
# define        INITIAL_CONFIG0 0x00008002
#elif defined(CYGPKG_HAL_MIPS_LSBFIRST)
# define        INITIAL_CONFIG0 0x00000002
#else
# error MIPS endianness not set by configuration
#endif

#------------------------------------------------------------------------------
# Set up initial value for FPU FCR31 register. We set the FS bit to flush
# denormalized results to zero and enable div-by-zero exceptions.

#ifndef CYG_HAL_MIPS_FCSR_INIT
#define CYG_HAL_MIPS_FCSR_INIT 0x01000400
#endif

#------------------------------------------------------------------------------
# Cache macros.
        
#ifndef CYGPKG_HAL_MIPS_CACHE_DEFINED

        .macro  hal_cache_init

	mfc0	v0,config0		# disable Kseg0 caching in config0 register
	nop
	nop
	la	v1,0xfffffff8
	and	v0,v0,v1
	ori	v0,v0,2
	mtc0	v0,config0
	nop
	nop
	nop

        .set mips3                      # Set ISA to MIPS 3 to allow cache insns

        # Now ensure the caches are invalidated. The caches are NOT cleared or
        # invalidated on non-power-up resets and may come up in a random state
        # on power-up. Hence they may contain stale or randomly bogus data.
        # Here we use the index-store-tag cache operation to clear all the 
        # cache tags and states to zero. This will render them all invalid on 
        # the RM7000.

        mtc0    zero,taglo
        mtc0    zero,taghi

        # D-cache:
        la      t0,CYGHWR_HAL_MIPS_RM7000_CACHE_SCRUB_BASE
        ori     t1,t0,HAL_DCACHE_SIZE
1:
        cache   0x09,0x0000(t0)
        cache   0x09,0x1000(t0)
        cache   0x09,0x2000(t0)
        cache   0x09,0x3000(t0)

	# Clear area so Icache loads below will read valid
	# instructions.
	sw	zero,0x00(t0)
	sw	zero,0x04(t0)
	sw	zero,0x08(t0)
	sw	zero,0x0c(t0)
	sw	zero,0x10(t0)
	sw	zero,0x14(t0)
	sw	zero,0x18(t0)
	sw	zero,0x1c(t0)
	
        addi    t0,t0,0x20
        sub     v0,t1,t0
        bgez    v0,1b
         nop

        # I-cache:
        la      a0,CYGHWR_HAL_MIPS_RM7000_CACHE_SCRUB_BASE
        ori     a1,a0,HAL_ICACHE_SIZE
1:
        cache   0x08,0x0000(a0)
        cache   0x08,0x1000(a0)
        cache   0x08,0x2000(a0)
        cache   0x08,0x3000(a0)

	# Needs extra scrubbing due to RM7000A erratum #31
        cache   0x14,0x0000(a0)
        cache   0x14,0x1000(a0)
        cache   0x14,0x2000(a0)
        cache   0x14,0x3000(a0)
        cache   0x08,0x0000(a0)
        cache   0x08,0x1000(a0)
        cache   0x08,0x2000(a0)
        cache   0x08,0x3000(a0)

        addi    a0,a0,0x20
        sub     v0,a1,a0
        bgez    v0,1b
         nop

        .set mips0                      # reset ISA to default

        .endm

#define CYGPKG_HAL_MIPS_CACHE_DEFINED

#endif  

#------------------------------------------------------------------------------
#endif // ifndef CYGONCE_HAL_VARIANT_INC
# end of variant.inc