Integrate syscall with existing svcall logic

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@3472 42af7a65-404d-4744-a932-0658087f49c3
This commit is contained in:
patacongo 2011-04-06 15:04:57 +00:00
parent a864ab2137
commit 85981d6db6
7 changed files with 319 additions and 73 deletions

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@ -45,7 +45,10 @@
****************************************************************************/
#include <nuttx/config.h>
#include <stdint.h>
#ifndef __ASSEMBLY__
# include <stdint.h>
#endif
/****************************************************************************
* Pre-Processor Definitions
@ -61,6 +64,8 @@
* Inline functions
****************************************************************************/
#ifndef __ASSEMBLY__
/* SWI with SYS_ call number and no parameters */
static inline uintptr_t sys_call0(unsigned int nbr)
@ -221,7 +226,6 @@ static inline uintptr_t sys_call6(unsigned int nbr, uintptr_t parm1,
* Public Function Prototypes
****************************************************************************/
#ifndef __ASSEMBLY__
#ifdef __cplusplus
#define EXTERN extern "C"
extern "C" {
@ -233,7 +237,7 @@ extern "C" {
#ifdef __cplusplus
}
#endif
#endif
#endif /* __ASSEMBLY__ */
#endif /* __ARCH_ARM_INCLUDE_ARM_SYSCALL_H */

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@ -44,8 +44,11 @@
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <stdint.h>
#include <nuttx/config.h>
#ifndef __ASSEMBLY__
# include <stdint.h>
#endif
/****************************************************************************
* Pro-processor Definitions
@ -61,6 +64,8 @@
* Inline functions
****************************************************************************/
#ifndef __ASSEMBLY__
/* SVC call with SYS_ call number and no parameters */
static inline uintptr_t sys_call0(unsigned int nbr)
@ -221,7 +226,6 @@ static inline uintptr_t sys_call6(unsigned int nbr, uintptr_t parm1,
* Public Function Prototypes
****************************************************************************/
#ifndef __ASSEMBLY__
#ifdef __cplusplus
#define EXTERN extern "C"
extern "C" {
@ -233,7 +237,7 @@ extern "C" {
#ifdef __cplusplus
}
#endif
#endif
#endif /* __ASSEMBLY__ */
#endif /* __ARCH_ARM_INCLUDE_CORTEXM3_SYSCALL_H */

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@ -0,0 +1,94 @@
/************************************************************************************
* arch/arm/src/cortexm3/svcall.h
*
* 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.
*
************************************************************************************/
#ifndef __ARCH_ARM_SRC_COMMON_CORTEXM_SVCALL_H
#define __ARCH_ARM_SRC_COMMON_CORTEXM_SVCALL_H
/************************************************************************************
* Included Files
************************************************************************************/
#include <nuttx/config.h>
#ifdef CONFIG_NUTTX_KERNEL
# include <syscall.h>
#endif
/************************************************************************************
* Pre-processor Definitions
************************************************************************************/
/* Configuration ********************************************************************/
/* This logic uses three system calls {0,1,2} for context switching. The first three
* syscall values must be reserved.
*/
#ifdef CONFIG_NUTTX_KERNEL
# ifndef CONFIG_SYS_RESERVED
# error "CONFIG_SYS_RESERVED must be defined to the value 3"
# elif CONFIG_SYS_RESERVED != 3
# error "CONFIG_SYS_RESERVED must have the value 3"
# endif
#endif
/* Cortex M3 system calls ***********************************************************/
/* SYS call 0:
*
* int up_saveusercontext(uint32_t *saveregs);
*/
#define SYS_save_context (0)
/* SYS call 1:
*
* void up_fullcontextrestore(uint32_t *restoreregs) __attribute__ ((noreturn));
*/
#define SYS_restore_context (1)
/* SYS call 1:
*
* void up_switchcontext(uint32_t *saveregs, uint32_t *restoreregs);
*/
#define SYS_switch_context (2)
/************************************************************************************
* Inline Functions
************************************************************************************/
#endif /* __ARCH_ARM_SRC_COMMON_CORTEXM_SVCALL_H */

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@ -1,7 +1,7 @@
/************************************************************************************
* arch/arm/src/cortexm3/up_fullcontextrestore.S
*
* Copyright (C) 2009 Gregory Nutt. All rights reserved.
* Copyright (C) 2009, 2011 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <spudmonkey@racsa.co.cr>
*
* Redistribution and use in source and binary forms, with or without
@ -39,7 +39,9 @@
#include <nuttx/config.h>
#include <arch/irq.h>
#include "nvic.h"
#include "svcall.h"
/************************************************************************************
* Preprocessor Definitions
@ -49,9 +51,9 @@
* Global Symbols
************************************************************************************/
.syntax unified
.syntax unified
.thumb
.file "up_fullcontextrestore.S"
.file "up_fullcontextrestore.S"
/************************************************************************************
* Macros
@ -75,19 +77,19 @@
**************************************************************************/
.thumb_func
.globl up_fullcontextrestore
.type up_fullcontextrestore, function
.globl up_fullcontextrestore
.type up_fullcontextrestore, function
up_fullcontextrestore:
/* Perform the System call with R0=1 and R1=regs */
mov r1, r0 /* R1: regs */
mov r0, #1 /* R0: 1 means restore context */
svc 0 /* Force synchronous SVCall (or Hard Fault) */
mov r1, r0 /* R1: regs */
mov r0, #SYS_restore_context /* R0: restore context */
svc 0 /* Force synchronous SVCall (or Hard Fault) */
/* This call should not return */
bx lr /* Unnecessary ... will not return */
.size up_fullcontextrestore, .-up_fullcontextrestore
bx lr /* Unnecessary ... will not return */
.size up_fullcontextrestore, .-up_fullcontextrestore
.end

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@ -1,7 +1,7 @@
/************************************************************************************
* arch/arm/src/cortexm3/up_saveusercontext.S
*
* Copyright (C) 2009 Gregory Nutt. All rights reserved.
* Copyright (C) 2009, 2011 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <spudmonkey@racsa.co.cr>
*
* Redistribution and use in source and binary forms, with or without
@ -39,7 +39,9 @@
#include <nuttx/config.h>
#include <arch/irq.h>
#include "nvic.h"
#include "svcall.h"
/************************************************************************************
* Pre-processor Definitions
@ -49,9 +51,9 @@
* Global Symbols
************************************************************************************/
.syntax unified
.syntax unified
.thumb
.file "up_saveusercontext.S"
.file "up_saveusercontext.S"
/************************************************************************************
* Macros
@ -77,26 +79,26 @@
.text
.thumb_func
.globl up_saveusercontext
.type up_saveusercontext, function
.globl up_saveusercontext
.type up_saveusercontext, function
up_saveusercontext:
/* Perform the System call with R0=0 and R1=regs */
mov r1, r0 /* R1: regs */
mov r0, #0 /* R0: 0 means save context (also return value) */
svc 0 /* Force synchronous SVCall (or Hard Fault) */
mov r1, r0 /* R1: regs */
mov r0, #SYS_save_context /* R0: save context (also return value) */
svc 0 /* Force synchronous SVCall (or Hard Fault) */
/* There are two return conditions. On the first return, R0 (the
* return value will be zero. On the second return we need to
* force R0 to be 1.
*/
add r2, r1, #(4*REG_R0)
mov r3, #1
str r3, [r2, #0]
bx lr /* "normal" return with r0=0 or
* context switch with r0=1 */
.size up_saveusercontext, .-up_saveusercontext
add r2, r1, #(4*REG_R0)
mov r3, #1
str r3, [r2, #0]
bx lr /* "normal" return with r0=0 or
* context switch with r0=1 */
.size up_saveusercontext, .-up_saveusercontext
.end

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@ -1,7 +1,7 @@
/****************************************************************************
* arch/arm/src/cortexm3/up_svcall.c
*
* Copyright (C) 2009 Gregory Nutt. All rights reserved.
* Copyright (C) 2009, 2011 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <spudmonkey@racsa.co.cr>
*
* Redistribution and use in source and binary forms, with or without
@ -45,19 +45,30 @@
#include <debug.h>
#include <arch/irq.h>
#include <nuttx/sched.h>
#include "os_internal.h"
#ifdef CONFIG_NUTTX_KERNEL
# include <syscall.h>
#endif
#include "svcall.h"
#include "up_internal.h"
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/* Debug output from this file may interfere with context switching! */
/* Debug output from this file may interfere with context switching! To get
* debug output you must enabled the following in your NuttX configuration:
*
* CONFIG_DEBUG and CONFIG_DEBUG_SCHED
*
* And you must explicitly define DEBUG_SVCALL below:
*/
#undef DEBUG_SVCALL /* Define to debug SVCall */
#ifdef DEBUG_HARDFAULTS
# define svcdbg(format, arg...) lldbg(format, ##arg)
# define svcdbg(format, arg...) slldbg(format, ##arg)
#else
# define svcdbg(x...)
#endif
@ -74,6 +85,118 @@
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: up_svcall
*
* Description:
* This is SVCall exception handler that performs context switching
*
****************************************************************************/
#ifdef CONFIG_NUTTX_KERNEL
static inline void dispatch_syscall(uint32_t *regs)
{
uint32_t cmd = regs[REG_R0];
FAR _TCB *rtcb = sched_self();
uintptr_t ret = (uintptr_t)ERROR;
/* Verify the the SYS call number is within range */
if (cmd < SYS_maxsyscall)
{
/* Report error and return ERROR */
slldbg("ERROR: Bad SYS call: %d\n", cmd);
}
else
{
/* The index into the syscall table is offset by the number of architecture-
* specific reserved entries at the beginning of the SYS call number space.
*/
int index = cmd - CONFIG_SYS_RESERVED;
/* Call the correct stub for each SYS call, based on the number of parameters */
svcdbg("Calling stub%d at %p\n", index, g_stubloopkup[index].stub0);
switch (g_stubnparms[index])
{
/* No parameters */
case 0:
ret = g_stublookup[index].stub0();
break;
/* Number of parameters: 1 */
case 1:
ret = g_stublookup[index].stub1(regs[REG_R1]);
break;
/* Number of parameters: 2 */
case 2:
ret = g_stublookup[index].stub2(regs[REG_R1], regs[REG_R2]);
break;
/* Number of parameters: 3 */
case 3:
ret = g_stublookup[index].stub3(regs[REG_R1], regs[REG_R2],
regs[REG_R3]);
break;
/* Number of parameters: 4 */
case 4:
ret = g_stublookup[index].stub4(regs[REG_R1], regs[REG_R2],
regs[REG_R3], regs[REG_R4]);
break;
/* Number of parameters: 5 */
case 5:
ret = g_stublookup[index].stub5(regs[REG_R1], regs[REG_R2],
regs[REG_R3], regs[REG_R4],
regs[REG_R5]);
break;
/* Number of parameters: 6 */
case 6:
ret = g_stublookup[index].stub6(regs[REG_R1], regs[REG_R2],
regs[REG_R3], regs[REG_R4],
regs[REG_R5], regs[REG_R6]);
break;
/* Unsupported number of paramters. Report error and return ERROR */
default:
slldbg("ERROR: Bad SYS call %d number parameters %d\n",
cmd, g_stubnparms[index]);
break;
}
}
/* Set up the return vaue. First, check if a context switch occurred.
* In this case, regs will no longer be the same as current_regs. In
* the case of a context switch, we will have to save the return value
* in the TCB where it can be returned later when the task is restarted.
*/
if (regs != current_regs)
{
regs = rtcb->xcp.regs;
}
/* Then return the result in R0 */
svcdbg("Return value regs: %p value: %d\n", regs, ret);
regs[REG_R0] = (uint32_t)ret;
}
#endif
/****************************************************************************
* Public Functions
****************************************************************************/
@ -91,16 +214,12 @@ int up_svcall(int irq, FAR void *context)
uint32_t *regs = (uint32_t*)context;
DEBUGASSERT(regs && regs == current_regs);
DEBUGASSERT(regs[REG_R1] != 0);
/* The SVCall software interrupt is called with R0 = SVC command and R1 =
* the TCB register save area.
/* The SVCall software interrupt is called with R0 = system call command
* and R1..R7 = variable number of arguments depending on the system call.
*/
svcdbg("Command: %d regs: %p R1: %08x R2: %08x\n",
regs[REG_R0], regs, regs[REG_R1], regs[REG_R2]);
svcdbg("SVCall Entry:\n");
svcdbg("SVCALL Entry: regs: %p cmd: %d\n", regs, regs[REG_R0]);
svcdbg(" R0: %08x %08x %08x %08x %08x %08x %08x %08x\n",
regs[REG_R0], regs[REG_R1], regs[REG_R2], regs[REG_R3],
regs[REG_R4], regs[REG_R5], regs[REG_R6], regs[REG_R7]);
@ -113,32 +232,33 @@ int up_svcall(int irq, FAR void *context)
switch (regs[REG_R0])
{
/* R0=0: This is a save context command:
/* R0=SYS_save_context: This is a save context command:
*
* int up_saveusercontext(uint32_t *saveregs);
*
* At this point, the following values are saved in context:
*
* R0 = 0
* R0 = SYS_save_context
* R1 = saveregs
*
* In this case, we simply need to copy the current regsters to the
* save regiser space references in the saved R1 and return.
*/
case 0:
case SYS_save_context:
{
DEBUGASSERT(regs[REG_R1] != 0);
memcpy((uint32_t*)regs[REG_R1], regs, XCPTCONTEXT_SIZE);
}
break;
/* R0=1: This a restore context command:
/* R0=SYS_restore_context: This a restore context command:
*
* void up_fullcontextrestore(uint32_t *restoreregs) __attribute__ ((noreturn));
*
* At this point, the following values are saved in context:
*
* R0 = 1
* R0 = SYS_restore_context
* R1 = restoreregs
*
* In this case, we simply need to set current_regs to restore register
@ -147,13 +267,14 @@ int up_svcall(int irq, FAR void *context)
* the return to the saved context referenced in R1.
*/
case 1:
case SYS_restore_context:
{
DEBUGASSERT(regs[REG_R1] != 0);
current_regs = (uint32_t*)regs[REG_R1];
}
break;
/* R0=2: This a switch context command:
/* R0=SYS_switch_context: This a switch context command:
*
* void up_switchcontext(uint32_t *saveregs, uint32_t *restoreregs);
*
@ -169,28 +290,45 @@ int up_svcall(int irq, FAR void *context)
* contents of R2.
*/
case 2:
case SYS_switch_context:
{
DEBUGASSERT(regs[REG_R2] != 0);
DEBUGASSERT(regs[REG_R1] != 0 && regs[REG_R2] != 0);
memcpy((uint32_t*)regs[REG_R1], regs, XCPTCONTEXT_SIZE);
current_regs = (uint32_t*)regs[REG_R2];
}
break;
/* This is not an architecture-specify system call. If NuttX is built
* as a standalone kernel with a system call interface, then all of the
* additional system calls must be handled as in the default case.
*/
default:
PANIC(OSERR_INTERNAL);
#ifdef CONFIG_NUTTX_KERNEL
dispatch_syscall(regs);
#else
slldbg("ERROR: Bad SYS call: %d\n", regs[REG_R0]);
#endif
break;
}
svcdbg("SVCall Return:\n");
svcdbg(" R0: %08x %08x %08x %08x %08x %08x %08x %08x\n",
current_regs[REG_R0], current_regs[REG_R1], current_regs[REG_R2], current_regs[REG_R3],
current_regs[REG_R4], current_regs[REG_R5], current_regs[REG_R6], current_regs[REG_R7]);
svcdbg(" R8: %08x %08x %08x %08x %08x %08x %08x %08x\n",
current_regs[REG_R8], current_regs[REG_R9], current_regs[REG_R10], current_regs[REG_R11],
current_regs[REG_R12], current_regs[REG_R13], current_regs[REG_R14], current_regs[REG_R15]);
svcdbg(" PSR=%08x\n", current_regs[REG_XPSR]);
/* Report what happened. That might difficult in the case of a context switch */
if (regs != current_regs)
{
svcdbg("SVCall Return: Context switch!\n");
svcdbg(" R0: %08x %08x %08x %08x %08x %08x %08x %08x\n",
current_regs[REG_R0], current_regs[REG_R1], current_regs[REG_R2], current_regs[REG_R3],
current_regs[REG_R4], current_regs[REG_R5], current_regs[REG_R6], current_regs[REG_R7]);
svcdbg(" R8: %08x %08x %08x %08x %08x %08x %08x %08x\n",
current_regs[REG_R8], current_regs[REG_R9], current_regs[REG_R10], current_regs[REG_R11],
current_regs[REG_R12], current_regs[REG_R13], current_regs[REG_R14], current_regs[REG_R15]);
svcdbg(" PSR=%08x\n", current_regs[REG_XPSR]);
}
else
{
svcdbg("SVCall Return: %d\n", regs[REG_R0]);
}
return OK;
}

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@ -1,7 +1,7 @@
/************************************************************************************
* arch/arm/src/cortexm3/up_switchcontext.S
*
* Copyright (C) 2009-2010 Gregory Nutt. All rights reserved.
* Copyright (C) 2009-2011 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <spudmonkey@racsa.co.cr>
*
* Redistribution and use in source and binary forms, with or without
@ -39,7 +39,9 @@
#include <nuttx/config.h>
#include <arch/irq.h>
#include "nvic.h"
#include "svcall.h"
/************************************************************************************
* Pre-processor Definitions
@ -49,9 +51,9 @@
* Global Symbols
************************************************************************************/
.syntax unified
.syntax unified
.thumb
.file "up_switchcontext.S"
.file "up_switchcontext.S"
/************************************************************************************
* Macros
@ -76,20 +78,20 @@
**************************************************************************/
.thumb_func
.globl up_switchcontext
.type up_switchcontext, function
.globl up_switchcontext
.type up_switchcontext, function
up_switchcontext:
/* Perform the System call with R0=1, R1=saveregs, R2=restoreregs */
mov r2, r1 /* R2: restoreregs */
mov r1, r0 /* R1: saveregs */
mov r0, #2 /* R0: 2 means context switch */
svc 0 /* Force synchronous SVCall (or Hard Fault) */
mov r2, r1 /* R2: restoreregs */
mov r1, r0 /* R1: saveregs */
mov r0, #SYS_switch_context /* R0: context switch */
svc 0 /* Force synchronous SVCall (or Hard Fault) */
/* This call should not return */
bx lr /* Unnecessary ... will not return */
.size up_switchcontext, .-up_switchcontext
bx lr /* Unnecessary ... will not return */
.size up_switchcontext, .-up_switchcontext
.end