diff options
Diffstat (limited to 'nuttx/arch/arm/src/cortexm3/up_svcall.c')
| -rw-r--r-- | nuttx/arch/arm/src/cortexm3/up_svcall.c | 84 |
1 files changed, 66 insertions, 18 deletions
diff --git a/nuttx/arch/arm/src/cortexm3/up_svcall.c b/nuttx/arch/arm/src/cortexm3/up_svcall.c index 3a346881f..e559074cc 100644 --- a/nuttx/arch/arm/src/cortexm3/up_svcall.c +++ b/nuttx/arch/arm/src/cortexm3/up_svcall.c @@ -81,50 +81,98 @@ int up_svcall(int irq, FAR void *context) { - uint32 *svregs = (uint32*)context; - uint32 *tcbregs = (uint32*)svregs[REG_R1]; + uint32 *regs = (uint32*)context; - DEBUGASSERT(svregs && svregs == current_regs && tcbregs); + 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. */ - sllvdbg("Command: %d svregs: %p tcbregs: %08x\n", svregs[REG_R0], svregs, tcbregs); + sllvdbg("Command: %d regs: %p R1: %08x R2: %08x\n", + regs[REG_R0], regs, regs[REG_R1], regs[REG_R2]); #ifdef DEBUG_SVCALL lldbg("SVCall Entry:\n"); lldbg(" R0: %08x %08x %08x %08x %08x %08x %08x %08x\n", - svregs[REG_R0], svregs[REG_R1], svregs[REG_R2], svregs[REG_R3], - svregs[REG_R4], svregs[REG_R5], svregs[REG_R6], svregs[REG_R7]); + regs[REG_R0], regs[REG_R1], regs[REG_R2], regs[REG_R3], + regs[REG_R4], regs[REG_R5], regs[REG_R6], regs[REG_R7]); lldbg(" R8: %08x %08x %08x %08x %08x %08x %08x %08x\n", - svregs[REG_R8], svregs[REG_R9], svregs[REG_R10], svregs[REG_R11], - svregs[REG_R12], svregs[REG_R13], svregs[REG_R14], svregs[REG_R15]); - lldbg(" PSR=%08x\n", svregs[REG_XPSR]); + regs[REG_R8], regs[REG_R9], regs[REG_R10], regs[REG_R11], + regs[REG_R12], regs[REG_R13], regs[REG_R14], regs[REG_R15]); + lldbg(" PSR=%08x\n", regs[REG_XPSR]); #endif /* Handle the SVCall according to the command in R0 */ - switch (svregs[REG_R0]) + switch (regs[REG_R0]) { - /* R0=0: This is a save context command. In this case, we simply need - * to copy the svregs to the tdbregs and return. + /* R0=0: This is a save context command: + * + * int up_saveusercontext(uint32 *saveregs); + * + * At this point, the following values are saved in context: + * + * R0 = 0 + * 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: - memcpy(tcbregs, svregs, XCPTCONTEXT_SIZE); + { + memcpy((uint32*)regs[REG_R1], regs, XCPTCONTEXT_SIZE); + } break; - /* R1=1: This a restore context command. In this case, we simply need to - * set current_regs to tcbrgs. svregs == current_regs is the normal exception - * turn. By setting current_regs = tcbregs, we force the return through - * the saved context. + /* R0=1: This a restore context command: + * + * void up_fullcontextrestore(uint32 *restoreregs) __attribute__ ((noreturn)); + * + * At this point, the following values are saved in context: + * + * R0 = 1 + * R1 = restoreregs + * + * In this case, we simply need to set current_regs to restore register + * area referenced in the saved R1. context == current_regs is the normal + * exception return. By setting current_regs = context[R1], we force + * the return to the saved context referenced in R1. */ case 1: - current_regs = tcbregs; + { + current_regs = (uint32*)regs[REG_R1]; + } break; + /* R0=2: This a switch context command: + * + * void up_switchcontext(uint32 *saveregs, uint32 *restoreregs); + * + * At this point, the following values are saved in context: + * + * R0 = 1 + * R1 = saveregs + * R2 = restoreregs + * + * In this case, we do both: We save the context registers to the save + * register area reference by the saved contents of R1 nad then set + * current_regs to to the save register area referenced by the saved + * contents of R2. + */ + + case 2: + { + DEBUGASSERT(regs[REG_R2] != 0); + memcpy((uint32*)regs[REG_R1], regs, XCPTCONTEXT_SIZE); + current_regs = (uint32*)regs[REG_R2]; + } + break; + + default: PANIC(OSERR_INTERNAL); break; |