linux/arch/arm/nwfpe/fpmodule.inl
Russell King b66da4a485 [PATCH] ARM: Remove global nwfpe register variable
Recent changes to nwfpe broke the build with some gcc versions:

In file included from arch/arm/nwfpe/softfloat.c:33:
arch/arm/nwfpe/fpa11.h:32: global register variable follows a function definition
make[1]: *** [arch/arm/nwfpe/softfloat.o] Error 1

Since we now ensure that the kernel stack is empty when returning
to user space, we can now access the userspace registers with
reference to the kernel stack using current_thread_info(), rather
than remembering the stack pointer at the time nwfpe was called.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2005-07-17 10:54:50 +01:00

74 lines
2.2 KiB
C++

/*
NetWinder Floating Point Emulator
(c) Rebel.COM, 1998,1999
Direct questions, comments to Scott Bambrough <scottb@netwinder.org>
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
static inline unsigned long readRegister(const unsigned int nReg)
{
/* Note: The CPU thinks it has dealt with the current instruction.
As a result the program counter has been advanced to the next
instruction, and points 4 bytes beyond the actual instruction
that caused the invalid instruction trap to occur. We adjust
for this in this routine. LDF/STF instructions with Rn = PC
depend on the PC being correct, as they use PC+8 in their
address calculations. */
struct pt_regs *regs = GET_USERREG();
unsigned int val = regs->uregs[nReg];
if (REG_PC == nReg)
val -= 4;
return val;
}
static inline void
writeRegister(const unsigned int nReg, const unsigned long val)
{
struct pt_regs *regs = GET_USERREG();
regs->uregs[nReg] = val;
}
static inline unsigned long readCPSR(void)
{
return (readRegister(REG_CPSR));
}
static inline void writeCPSR(const unsigned long val)
{
writeRegister(REG_CPSR, val);
}
static inline unsigned long readConditionCodes(void)
{
#ifdef __FPEM_TEST__
return (0);
#else
return (readCPSR() & CC_MASK);
#endif
}
static inline void writeConditionCodes(const unsigned long val)
{
struct pt_regs *regs = GET_USERREG();
unsigned long rval;
/*
* Operate directly on userRegisters since
* the CPSR may be the PC register itself.
*/
rval = regs->ARM_cpsr & ~CC_MASK;
regs->ARM_cpsr = rval | (val & CC_MASK);
}