Commit 781125ca authored by Paul Mundt's avatar Paul Mundt

sh: New atomic ops for SH-4A movli.l/movco.l

SH-4A implements LL/SC instructions, so we implement a simple
set of atomic operations using these.
Signed-off-by: default avatarPaul Mundt <lethal@linux-sh.org>
parent 15f57a29
......@@ -22,49 +22,110 @@ typedef struct { volatile int counter; } atomic_t;
* forward to code at the end of this object's .text section, then
* branch back to restart the operation.
*/
static __inline__ void atomic_add(int i, atomic_t * v)
static inline void atomic_add(int i, atomic_t *v)
{
#ifdef CONFIG_CPU_SH4A
unsigned long tmp;
__asm__ __volatile__ (
"1: movli.l @%3, %0 ! atomic_add \n"
" add %2, %0 \n"
" movco.l %0, @%3 \n"
" bf 1b \n"
: "=&z" (tmp), "=r" (&v->counter)
: "r" (i), "r" (&v->counter)
: "t");
#else
unsigned long flags;
local_irq_save(flags);
*(long *)v += i;
local_irq_restore(flags);
#endif
}
static __inline__ void atomic_sub(int i, atomic_t *v)
static inline void atomic_sub(int i, atomic_t *v)
{
#ifdef CONFIG_CPU_SH4A
unsigned long tmp;
__asm__ __volatile__ (
"1: movli.l @%3, %0 ! atomic_sub \n"
" sub %2, %0 \n"
" movco.l %0, @%3 \n"
" bf 1b \n"
: "=&z" (tmp), "=r" (&v->counter)
: "r" (i), "r" (&v->counter)
: "t");
#else
unsigned long flags;
local_irq_save(flags);
*(long *)v -= i;
local_irq_restore(flags);
#endif
}
static __inline__ int atomic_add_return(int i, atomic_t * v)
/*
* SH-4A note:
*
* We basically get atomic_xxx_return() for free compared with
* atomic_xxx(). movli.l/movco.l require r0 due to the instruction
* encoding, so the retval is automatically set without having to
* do any special work.
*/
static inline int atomic_add_return(int i, atomic_t *v)
{
unsigned long temp, flags;
unsigned long temp;
#ifdef CONFIG_CPU_SH4A
__asm__ __volatile__ (
"1: movli.l @%3, %0 ! atomic_add_return \n"
" add %2, %0 \n"
" movco.l %0, @%3 \n"
" bf 1b \n"
" synco \n"
: "=&z" (temp), "=r" (&v->counter)
: "r" (i), "r" (&v->counter)
: "t");
#else
unsigned long flags;
local_irq_save(flags);
temp = *(long *)v;
temp += i;
*(long *)v = temp;
local_irq_restore(flags);
#endif
return temp;
}
#define atomic_add_negative(a, v) (atomic_add_return((a), (v)) < 0)
static __inline__ int atomic_sub_return(int i, atomic_t * v)
static inline int atomic_sub_return(int i, atomic_t *v)
{
unsigned long temp, flags;
unsigned long temp;
#ifdef CONFIG_CPU_SH4A
__asm__ __volatile__ (
"1: movli.l @%3, %0 ! atomic_sub_return \n"
" sub %2, %0 \n"
" movco.l %0, @%3 \n"
" bf 1b \n"
" synco \n"
: "=&z" (temp), "=r" (&v->counter)
: "r" (i), "r" (&v->counter)
: "t");
#else
unsigned long flags;
local_irq_save(flags);
temp = *(long *)v;
temp -= i;
*(long *)v = temp;
local_irq_restore(flags);
#endif
return temp;
}
......@@ -119,22 +180,48 @@ static inline int atomic_add_unless(atomic_t *v, int a, int u)
}
#define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0)
static __inline__ void atomic_clear_mask(unsigned int mask, atomic_t *v)
static inline void atomic_clear_mask(unsigned int mask, atomic_t *v)
{
#ifdef CONFIG_CPU_SH4A
unsigned long tmp;
__asm__ __volatile__ (
"1: movli.l @%3, %0 ! atomic_clear_mask \n"
" and %2, %0 \n"
" movco.l %0, @%3 \n"
" bf 1b \n"
: "=&z" (tmp), "=r" (&v->counter)
: "r" (~mask), "r" (&v->counter)
: "t");
#else
unsigned long flags;
local_irq_save(flags);
*(long *)v &= ~mask;
local_irq_restore(flags);
#endif
}
static __inline__ void atomic_set_mask(unsigned int mask, atomic_t *v)
static inline void atomic_set_mask(unsigned int mask, atomic_t *v)
{
#ifdef CONFIG_CPU_SH4A
unsigned long tmp;
__asm__ __volatile__ (
"1: movli.l @%3, %0 ! atomic_set_mask \n"
" or %2, %0 \n"
" movco.l %0, @%3 \n"
" bf 1b \n"
: "=&z" (tmp), "=r" (&v->counter)
: "r" (mask), "r" (&v->counter)
: "t");
#else
unsigned long flags;
local_irq_save(flags);
*(long *)v |= mask;
local_irq_restore(flags);
#endif
}
/* Atomic operations are already serializing on SH */
......
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