linux/arch/powerpc/include/asm/inst.h
Jordan Niethe 50428fdc53 powerpc: Add a ppc_inst_as_str() helper
There are quite a few places where instructions are printed, this is
done using a '%x' format specifier. With the introduction of prefixed
instructions, this does not work well. Currently in these places,
ppc_inst_val() is used for the value for %x so only the first word of
prefixed instructions are printed.

When the instructions are word instructions, only a single word should
be printed. For prefixed instructions both the prefix and suffix should
be printed. To accommodate both of these situations, instead of a '%x'
specifier use '%s' and introduce a helper, __ppc_inst_as_str() which
returns a char *. The char * __ppc_inst_as_str() returns is buffer that
is passed to it by the caller.

It is cumbersome to require every caller of __ppc_inst_as_str() to now
declare a buffer. To make it more convenient to use __ppc_inst_as_str(),
wrap it in a macro that uses a compound statement to allocate a buffer
on the caller's stack before calling it.

Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Acked-by: Segher Boessenkool <segher@kernel.crashing.org>
[mpe: Drop 0x prefix to match most existings uses, especially xmon]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200602052728.18227-1-jniethe5@gmail.com
2020-07-23 17:41:36 +10:00

151 lines
3.0 KiB
C

/* SPDX-License-Identifier: GPL-2.0-or-later */
#ifndef _ASM_POWERPC_INST_H
#define _ASM_POWERPC_INST_H
#include <asm/ppc-opcode.h>
/*
* Instruction data type for POWER
*/
struct ppc_inst {
u32 val;
#ifdef CONFIG_PPC64
u32 suffix;
#endif
} __packed;
static inline u32 ppc_inst_val(struct ppc_inst x)
{
return x.val;
}
static inline int ppc_inst_primary_opcode(struct ppc_inst x)
{
return ppc_inst_val(x) >> 26;
}
#ifdef CONFIG_PPC64
#define ppc_inst(x) ((struct ppc_inst){ .val = (x), .suffix = 0xff })
#define ppc_inst_prefix(x, y) ((struct ppc_inst){ .val = (x), .suffix = (y) })
static inline u32 ppc_inst_suffix(struct ppc_inst x)
{
return x.suffix;
}
static inline bool ppc_inst_prefixed(struct ppc_inst x)
{
return (ppc_inst_primary_opcode(x) == 1) && ppc_inst_suffix(x) != 0xff;
}
static inline struct ppc_inst ppc_inst_swab(struct ppc_inst x)
{
return ppc_inst_prefix(swab32(ppc_inst_val(x)),
swab32(ppc_inst_suffix(x)));
}
static inline struct ppc_inst ppc_inst_read(const struct ppc_inst *ptr)
{
u32 val, suffix;
val = *(u32 *)ptr;
if ((val >> 26) == OP_PREFIX) {
suffix = *((u32 *)ptr + 1);
return ppc_inst_prefix(val, suffix);
} else {
return ppc_inst(val);
}
}
static inline bool ppc_inst_equal(struct ppc_inst x, struct ppc_inst y)
{
return *(u64 *)&x == *(u64 *)&y;
}
#else
#define ppc_inst(x) ((struct ppc_inst){ .val = x })
static inline bool ppc_inst_prefixed(struct ppc_inst x)
{
return false;
}
static inline u32 ppc_inst_suffix(struct ppc_inst x)
{
return 0;
}
static inline struct ppc_inst ppc_inst_swab(struct ppc_inst x)
{
return ppc_inst(swab32(ppc_inst_val(x)));
}
static inline struct ppc_inst ppc_inst_read(const struct ppc_inst *ptr)
{
return *ptr;
}
static inline bool ppc_inst_equal(struct ppc_inst x, struct ppc_inst y)
{
return ppc_inst_val(x) == ppc_inst_val(y);
}
#endif /* CONFIG_PPC64 */
static inline int ppc_inst_len(struct ppc_inst x)
{
return ppc_inst_prefixed(x) ? 8 : 4;
}
/*
* Return the address of the next instruction, if the instruction @value was
* located at @location.
*/
static inline struct ppc_inst *ppc_inst_next(void *location, struct ppc_inst *value)
{
struct ppc_inst tmp;
tmp = ppc_inst_read(value);
return location + ppc_inst_len(tmp);
}
static inline u64 ppc_inst_as_u64(struct ppc_inst x)
{
#ifdef CONFIG_CPU_LITTLE_ENDIAN
return (u64)ppc_inst_suffix(x) << 32 | ppc_inst_val(x);
#else
return (u64)ppc_inst_val(x) << 32 | ppc_inst_suffix(x);
#endif
}
#define PPC_INST_STR_LEN sizeof("00000000 00000000")
static inline char *__ppc_inst_as_str(char str[PPC_INST_STR_LEN], struct ppc_inst x)
{
if (ppc_inst_prefixed(x))
sprintf(str, "%08x %08x", ppc_inst_val(x), ppc_inst_suffix(x));
else
sprintf(str, "%08x", ppc_inst_val(x));
return str;
}
#define ppc_inst_as_str(x) \
({ \
char __str[PPC_INST_STR_LEN]; \
__ppc_inst_as_str(__str, x); \
__str; \
})
int probe_user_read_inst(struct ppc_inst *inst,
struct ppc_inst __user *nip);
int probe_kernel_read_inst(struct ppc_inst *inst,
struct ppc_inst *src);
#endif /* _ASM_POWERPC_INST_H */