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