More context switching logic for m9s12

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@3300 42af7a65-404d-4744-a932-0658087f49c3
This commit is contained in:
patacongo 2011-02-18 01:28:35 +00:00
parent 1e7890b0f8
commit 2a570434fc
4 changed files with 267 additions and 6 deletions

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@ -147,8 +147,9 @@
# define REG_PCH (REG_FIRST_HARDREG+17)
# define REG_PCL (REG_FIRST_HARDREG+18)
#define TOTALFRAME_SIZE (REG_FIRST_HARDREG+17)
#define INTFRAME_SIZE 9
#define XCPTCONTEXT_REGS (REG_FIRST_HARDREG+17)
#define XCPTCONTEXT_REGS TOTALFRAME_SIZE
/************************************************************************************
* Public Types

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@ -41,5 +41,5 @@ CMN_CSRCS = up_allocateheap.c up_createstack.c up_doirq.c up_idle.c up_initializ
up_modifyreg32.c up_modifyreg8.c up_puts.c up_releasestack.c \
up_udelay.c up_usestack.c
CHIP_ASRCS = m9s12_start.S m9s12_lowputc.S
CHIP_ASRCS = m9s12_start.S m9s12_lowputc.S m9s12_saveusercontext.S
CHIP_CSRCS = m9s12_assert.c m9s12_serial.c m9s12_irq.c

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@ -0,0 +1,181 @@
/**************************************************************************
* arch/arm/src/m9s12/m9s12_saveusercontext.S
*
* Copyright (C) 2011 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <spudmonkey@racsa.co.cr>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
**************************************************************************/
/**************************************************************************
* Included Files
**************************************************************************/
#include <nuttx/config.h>
#include <arch/irq.h>
#include "up_internal.h"
#include "m9s12_internal.h"
/**************************************************************************
* Private Definitions
**************************************************************************/
/**************************************************************************
* Private Types
**************************************************************************/
/**************************************************************************
* Private Function Prototypes
**************************************************************************/
/**************************************************************************
* Global Variables
**************************************************************************/
/**************************************************************************
* Private Variables
**************************************************************************/
/**************************************************************************
* Private Functions
**************************************************************************/
/**************************************************************************
* Public Functions
**************************************************************************/
/**************************************************************************
* Name: up_saveusercontext
*
* Description:
* Create this state save strucure:
* Low Address [PPAGE]
* [soft regisers]
* XYH
* XYL
* ZH
* ZL
* TMPH
* TMPL
* FRAMEH
* FRAMEL
* SP <-- SP after interrupt
* CCR
* B
* A
* XH
* XL
* YH
* YL
* PCH
* High Address PCL
*
* On entry:
* D=Pointer to save save structure
* TOS=return address
*
**************************************************************************/
.text
.globl up_saveusercontext
.type up_saveusercontext, function
up_saveusercontext:
/* Exchange D with X. Now X points to the save structure. */
xgdx
/* Save he PPAGE register */
#ifndef CONFIG_HCS12_NONBANKED
movb HCS12_MMC_PPAGE, 1, x+
#endif
/* Save the soft registers */
#if CONFIG_HCS12_MSOFTREGS > 2
# error "Need to save more registers"
#endif
#if CONFIG_HCS12_MSOFTREGS > 1
movw _.d2, 2, x+
#endif
#if CONFIG_HCS12_MSOFTREGS > 0
movw _.d1, 2, x+
#endif
/* It is not necessary to save the value of _.tmp, _.z, or _.xy */
ldd #0
std 2, x+ /* Save _.xy = 0 */
std 2, x+ /* Save _.z = 0 */
std 2, x+ /* Save _.tmp = 0 */
/* Save _.frame */
movw _.frame, 2, x+
/* Save the value of the stack "before" this function was called */
tfr sp, d /* D = current SP */
addd #(TOTALFRAME_SIZE-INTFRAME_SIZE)
std 2, x+ /* Save the value of SP on entry */
/* Save the CCR */
tpa /* A = CCR */
staa 1, x+ /* Save CCR in the structure */
/* D (A:B) is the return value. Save 1 as the new return value as it
* will appear after a context switch back to the current thread.
*/
ldd #1
std 2, x+ /* Save D = 1 */
/* X, Y do not need to be preserved. Write zeros to these locations */
ldd #0
std 2, x+ /* Save X = 0 */
std 2, x+ /* Save Y = 0 */
/* Fetch the 2-byte return address from the stack and save it at the
* end of the state save area
*/
movw 0, sp, 2, x+ /* Save PCH and PCL */
#if __INT__ == 32 /* 32-bit ABI */
ldx #0
#endif
clra
clrb
rts
.size up_saveusercontext, . - up_saveusercontext
.end

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@ -51,6 +51,7 @@
.globl __start
.globl up_doirq
.globl up_fullcontextrestore
.file "m9s12_vectors.S"
/************************************************************************************
@ -204,9 +205,11 @@ handlers:
HANDLER villegal, HCS12_IRQ_VILLEGAL /* Any reserved vector */
/************************************************************************************
* Common IRQ handling logic
* Name: vcommon
*
* Description:
* Common IRQ handling logic
*
* On entry in to vcommon: (1) The interrupt stack fram is in place, and (2) the
* IRQ number is in B.
*
@ -214,6 +217,7 @@ handlers:
* instruction interrupt, the stack frame created by hardware looks like:
*
* Low Address <-- SP after interrupt
* CCR
* B
* A
* XH
@ -237,6 +241,7 @@ handlers:
* FRAMEH
* FRAMEL
* SP <-- SP after interrupt
* CCR
* B
* A
* XH
@ -302,10 +307,8 @@ vcommon:
/* Check if the return value in d is the same as regs parameter passed in the TOS */
cpd .Lspsave
beq .Lnoswitch
#warning "Missing Logic"
bne up_fullcontextrestore
.Lnoswitch:
/* Restore registers and return */
/* Restore the PPAGE register */
@ -335,6 +338,82 @@ vcommon:
rti
.size handlers, .-handlers
/************************************************************************************
* Name: up_fullcontextrestore
*
* Description:
* Given a pointer to a register save block that was previously created by either
* interrupt handler or by up_saveusercontext(), restore the context of the saved
* thread, thereby completing a context switch.
*
* Low Address [PPAGE]
* [soft regisers]
* XYH
* XYL
* ZH
* ZL
* TMPH
* TMPL
* FRAMEH
* FRAMEL
* SP
* CCR
* B
* A
* XH
* XL
* YH
* YL
* PCH
* High Address PCL
*
* On entry:
* D = Address of the context switch save block
*
************************************************************************************/
up_fullcontextrestore:
/* Make sure that interrupts are dissabled */
orcc #0x50
/* Exchange D with X. Now X points to the save structure. */
xgdx
/* Recover PPAGE */
#ifndef CONFIG_HCS12_NONBANKED
movb 1, x+, HCS12_MMC_PPAGE
#endif
/* Recover _.xy, _.z, _.tmp, _.frame */
movw 2, x+, _.xy
movw 2, x+, _.z
movw 2, x+, _.tmp
movw 2, x+, _.frame
/* Recover SP "before" the interrupt occurred */
ldd 2, x+
tfr d, sp
/* Now, create a new interrupt return frame */
ldab #(INTFRAME_SIZE-1) /* Offset to PCL */
abx /* X now points to last byte */
/* Copy the interrupt frame onto the stack */
movw 2, -sp, 2, -x /* Copy the PC */
movw 2, -sp, 2, -x /* Copy Y */
movw 2, -sp, 2, -x /* Copy X */
movw 2, -sp, 2, -x /* Copy A:B */
movw 1, -sp, 1, -x /* Copy CCR */
rti /* And return from interrupt */
.size up_fullcontextrestore, .-up_fullcontextrestore
/************************************************************************************
* .bss
************************************************************************************/