1/* 2 NetWinder Floating Point Emulator 3 (c) Rebel.COM, 1998,1999 4 5 Direct questions, comments to Scott Bambrough <scottb@netwinder.org> 6 7 This program is free software; you can redistribute it and/or modify 8 it under the terms of the GNU General Public License as published by 9 the Free Software Foundation; either version 2 of the License, or 10 (at your option) any later version. 11 12 This program is distributed in the hope that it will be useful, 13 but WITHOUT ANY WARRANTY; without even the implied warranty of 14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15 GNU General Public License for more details. 16 17 You should have received a copy of the GNU General Public License 18 along with this program; if not, write to the Free Software 19 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 20*/ 21 22static inline unsigned long readRegister(const unsigned int nReg) 23{ 24 /* Note: The CPU thinks it has dealt with the current instruction. 25 As a result the program counter has been advanced to the next 26 instruction, and points 4 bytes beyond the actual instruction 27 that caused the invalid instruction trap to occur. We adjust 28 for this in this routine. LDF/STF instructions with Rn = PC 29 depend on the PC being correct, as they use PC+8 in their 30 address calculations. */ 31 struct pt_regs *regs = GET_USERREG(); 32 unsigned int val = regs->uregs[nReg]; 33 if (REG_PC == nReg) 34 val -= 4; 35 return val; 36} 37 38static inline void 39writeRegister(const unsigned int nReg, const unsigned long val) 40{ 41 struct pt_regs *regs = GET_USERREG(); 42 regs->uregs[nReg] = val; 43} 44 45static inline unsigned long readCPSR(void) 46{ 47 return (readRegister(REG_CPSR)); 48} 49 50static inline void writeCPSR(const unsigned long val) 51{ 52 writeRegister(REG_CPSR, val); 53} 54 55static inline unsigned long readConditionCodes(void) 56{ 57#ifdef __FPEM_TEST__ 58 return (0); 59#else 60 return (readCPSR() & CC_MASK); 61#endif 62} 63 64static inline void writeConditionCodes(const unsigned long val) 65{ 66 struct pt_regs *regs = GET_USERREG(); 67 unsigned long rval; 68 /* 69 * Operate directly on userRegisters since 70 * the CPSR may be the PC register itself. 71 */ 72 rval = regs->ARM_cpsr & ~CC_MASK; 73 regs->ARM_cpsr = rval | (val & CC_MASK); 74} 75