host-aprom/NUC123/semihosting.h
2024-06-29 21:17:34 +01:00

117 lines
3.5 KiB
C

#ifndef ARM_SEMIHOSTING_H_
#define ARM_SEMIHOSTING_H_
// ----------------------------------------------------------------------------
// Semihosting operations.
enum OperationNumber
{
// Regular operations
SEMIHOSTING_EnterSVC = 0x17,
SEMIHOSTING_ReportException = 0x18,
SEMIHOSTING_SYS_CLOSE = 0x02,
SEMIHOSTING_SYS_CLOCK = 0x10,
SEMIHOSTING_SYS_ELAPSED = 0x30,
SEMIHOSTING_SYS_ERRNO = 0x13,
SEMIHOSTING_SYS_FLEN = 0x0C,
SEMIHOSTING_SYS_GET_CMDLINE = 0x15,
SEMIHOSTING_SYS_HEAPINFO = 0x16,
SEMIHOSTING_SYS_ISERROR = 0x08,
SEMIHOSTING_SYS_ISTTY = 0x09,
SEMIHOSTING_SYS_OPEN = 0x01,
SEMIHOSTING_SYS_READ = 0x06,
SEMIHOSTING_SYS_READC = 0x07,
SEMIHOSTING_SYS_REMOVE = 0x0E,
SEMIHOSTING_SYS_RENAME = 0x0F,
SEMIHOSTING_SYS_SEEK = 0x0A,
SEMIHOSTING_SYS_SYSTEM = 0x12,
SEMIHOSTING_SYS_TICKFREQ = 0x31,
SEMIHOSTING_SYS_TIME = 0x11,
SEMIHOSTING_SYS_TMPNAM = 0x0D,
SEMIHOSTING_SYS_WRITE = 0x05,
SEMIHOSTING_SYS_WRITEC = 0x03,
SEMIHOSTING_SYS_WRITE0 = 0x04,
// Codes returned by SEMIHOSTING_ReportException
ADP_Stopped_ApplicationExit = ((2 << 16) + 38),
ADP_Stopped_RunTimeError = ((2 << 16) + 35),
};
// ----------------------------------------------------------------------------
// SWI numbers and reason codes for RDI (Angel) monitors.
#define AngelSWI_ARM 0x123456
#ifdef __thumb__
#define AngelSWI 0xAB
#else
#define AngelSWI AngelSWI_ARM
#endif
// For thumb only architectures use the BKPT instruction instead of SWI.
#if defined(__ARM_ARCH_7M__) \
|| defined(__ARM_ARCH_7EM__) \
|| defined(__ARM_ARCH_6M__)
#define AngelSWIInsn "bkpt"
#define AngelSWIAsm bkpt
#else
#define AngelSWIInsn "swi"
#define AngelSWIAsm swi
#endif
#if defined(OS_DEBUG_SEMIHOSTING_FAULTS)
// Testing the local semihosting handler cannot use another BKPT, since this
// configuration cannot trigger HaedFault exceptions while the debugger is
// connected, so we use an illegal op code, that will trigger an
// UsageFault exception.
#define AngelSWITestFault "setend be"
#define AngelSWITestFaultOpCode (0xB658)
#endif
static inline int
__attribute__ ((always_inline))
call_host (int reason, void* arg)
{
int value;
asm volatile (
" mov r0, %[rsn] \n"
" mov r1, %[arg] \n"
#if defined(OS_DEBUG_SEMIHOSTING_FAULTS)
" " AngelSWITestFault " \n"
#else
" " AngelSWIInsn " %[swi] \n"
#endif
" mov %[val], r0"
: [val] "=r" (value) /* Outputs */
: [rsn] "r" (reason), [arg] "r" (arg), [swi] "i" (AngelSWI) /* Inputs */
: "r0", "r1", "r2", "r3", "ip", "lr", "memory", "cc"
// Clobbers r0 and r1, and lr if in supervisor mode
);
// Accordingly to page 13-77 of ARM DUI 0040D other registers
// can also be clobbered. Some memory positions may also be
// changed by a system call, so they should not be kept in
// registers. Note: we are assuming the manual is right and
// Angel is respecting the APCS.
return value;
}
// ----------------------------------------------------------------------------
// Function used in _exit() to return the status code as Angel exception.
static inline void
__attribute__ ((always_inline,noreturn))
report_exception (int reason)
{
call_host (SEMIHOSTING_ReportException, (void*) reason);
for (;;)
;
}
// ----------------------------------------------------------------------------
#endif // ARM_SEMIHOSTING_H_