target-arm: Support coprocessor registers which do I/O

Add an ARM_CP_IO flag which an ARMCPRegInfo definition can use to
indicate that the register's implementation does I/O and thus
its accesses need to be surrounded by gen_io_start()/gen_io_end()
in order for icount to work. Most notably, cp registers which
implement clocks or timers need this.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Tested-by: Laurent Desnogues <laurent.desnogues@gmail.com>
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@gmail.com>
Message-id: 1376065080-26661-3-git-send-email-peter.maydell@linaro.org
This commit is contained in:
Peter Maydell 2013-08-20 14:54:31 +01:00
parent 22d9e1a986
commit 2452731c88
2 changed files with 18 additions and 4 deletions

View File

@ -472,6 +472,9 @@ static inline uint64_t cpreg_to_kvm_id(uint32_t cpregid)
* old must have the OVERRIDE bit set.
* NO_MIGRATE indicates that this register should be ignored for migration;
* (eg because any state is accessed via some other coprocessor register).
* IO indicates that this register does I/O and therefore its accesses
* need to be surrounded by gen_io_start()/gen_io_end(). In particular,
* registers which implement clocks or timers require this.
*/
#define ARM_CP_SPECIAL 1
#define ARM_CP_CONST 2
@ -479,13 +482,14 @@ static inline uint64_t cpreg_to_kvm_id(uint32_t cpregid)
#define ARM_CP_SUPPRESS_TB_END 8
#define ARM_CP_OVERRIDE 16
#define ARM_CP_NO_MIGRATE 32
#define ARM_CP_IO 64
#define ARM_CP_NOP (ARM_CP_SPECIAL | (1 << 8))
#define ARM_CP_WFI (ARM_CP_SPECIAL | (2 << 8))
#define ARM_LAST_SPECIAL ARM_CP_WFI
/* Used only as a terminator for ARMCPRegInfo lists */
#define ARM_CP_SENTINEL 0xffff
/* Mask of only the flag bits in a type field */
#define ARM_CP_FLAG_MASK 0x3f
#define ARM_CP_FLAG_MASK 0x7f
/* Return true if cptype is a valid type field. This is used to try to
* catch errors where the sentinel has been accidentally left off the end

View File

@ -6280,6 +6280,10 @@ static int disas_coproc_insn(CPUARMState * env, DisasContext *s, uint32_t insn)
break;
}
if (use_icount && (ri->type & ARM_CP_IO)) {
gen_io_start();
}
if (isread) {
/* Read */
if (is64) {
@ -6369,14 +6373,20 @@ static int disas_coproc_insn(CPUARMState * env, DisasContext *s, uint32_t insn)
store_cpu_offset(tmp, ri->fieldoffset);
}
}
}
if (use_icount && (ri->type & ARM_CP_IO)) {
/* I/O operations must end the TB here (whether read or write) */
gen_io_end();
gen_lookup_tb(s);
} else if (!isread && !(ri->type & ARM_CP_SUPPRESS_TB_END)) {
/* We default to ending the TB on a coprocessor register write,
* but allow this to be suppressed by the register definition
* (usually only necessary to work around guest bugs).
*/
if (!(ri->type & ARM_CP_SUPPRESS_TB_END)) {
gen_lookup_tb(s);
}
gen_lookup_tb(s);
}
return 0;
}