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ARC: cacheflush refactor #3: Unify the {d,i}cache flush leaf helpers
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With Line length being constant now, we can fold the 2 helpers into 1.
This allows applying any optimizations (forthcoming) to single place.

Signed-off-by: Vineet Gupta <[email protected]>
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vineetgarc committed Nov 6, 2013
1 parent 63d2dfd commit bd12976
Showing 1 changed file with 55 additions and 84 deletions.
139 changes: 55 additions & 84 deletions arch/arc/mm/cache_arc700.c
Original file line number Diff line number Diff line change
Expand Up @@ -240,6 +240,59 @@ void arc_cache_init(void)
#define OP_INV 0x1
#define OP_FLUSH 0x2
#define OP_FLUSH_N_INV 0x3
#define OP_INV_IC 0x4

/*
* Common Helper for Line Operations on {I,D}-Cache
*/
static inline void __cache_line_loop(unsigned long paddr, unsigned long vaddr,
unsigned long sz, const int cacheop)
{
unsigned int aux_cmd, aux_tag;
int num_lines;

if (cacheop == OP_INV_IC) {
aux_cmd = ARC_REG_IC_IVIL;
aux_tag = ARC_REG_IC_PTAG;
}
else {
/* d$ cmd: INV (discard or wback-n-discard) OR FLUSH (wback) */
aux_cmd = cacheop & OP_INV ? ARC_REG_DC_IVDL : ARC_REG_DC_FLDL;
aux_tag = ARC_REG_DC_PTAG;
}

/* Ensure we properly floor/ceil the non-line aligned/sized requests
* and have @paddr - aligned to cache line and integral @num_lines.
* This however can be avoided for page sized since:
* -@paddr will be cache-line aligned already (being page aligned)
* -@sz will be integral multiple of line size (being page sized).
*/
if (!(__builtin_constant_p(sz) && sz == PAGE_SIZE)) {
sz += paddr & ~CACHE_LINE_MASK;
paddr &= CACHE_LINE_MASK;
vaddr &= CACHE_LINE_MASK;
}

num_lines = DIV_ROUND_UP(sz, L1_CACHE_BYTES);

#if (CONFIG_ARC_MMU_VER <= 2)
/* MMUv2 and before: paddr contains stuffed vaddrs bits */
paddr |= (vaddr >> PAGE_SHIFT) & 0x1F;
#endif

while (num_lines-- > 0) {
#if (CONFIG_ARC_MMU_VER > 2)
/* MMUv3, cache ops require paddr seperately */
write_aux_reg(ARC_REG_DC_PTAG, paddr);

write_aux_reg(aux_cmd, vaddr);
vaddr += L1_CACHE_BYTES;
#else
write_aux_reg(aux, paddr);
#endif
paddr += L1_CACHE_BYTES;
}
}

#ifdef CONFIG_ARC_HAS_DCACHE

Expand Down Expand Up @@ -289,55 +342,6 @@ static inline void __dc_entire_op(const int cacheop)
write_aux_reg(ARC_REG_DC_CTRL, tmp & ~DC_CTRL_INV_MODE_FLUSH);
}

/*
* Per Line Operation on D-Cache
* Doesn't deal with type-of-op/IRQ-disabling/waiting-for-flush-to-complete
* It's sole purpose is to help gcc generate ZOL
* (aliasing VIPT dcache flushing needs both vaddr and paddr)
*/
static inline void __dc_line_loop(unsigned long paddr, unsigned long vaddr,
unsigned long sz, const int cacheop)
{
/* d$ cmd: INV (discard or wback-n-discard) OR FLUSH (wback) */
const int aux = cacheop & OP_INV ? ARC_REG_DC_IVDL : ARC_REG_DC_FLDL;
int num_lines;

/* Ensure we properly floor/ceil the non-line aligned/sized requests
* and have @paddr - aligned to cache line and integral @num_lines.
* This however can be avoided for page sized since:
* -@paddr will be cache-line aligned already (being page aligned)
* -@sz will be integral multiple of line size (being page sized).
*/
if (!(__builtin_constant_p(sz) && sz == PAGE_SIZE)) {
sz += paddr & ~CACHE_LINE_MASK;
paddr &= CACHE_LINE_MASK;
vaddr &= CACHE_LINE_MASK;
}

num_lines = DIV_ROUND_UP(sz, L1_CACHE_BYTES);

#if (CONFIG_ARC_MMU_VER <= 2)
paddr |= (vaddr >> PAGE_SHIFT) & 0x1F;
#endif

while (num_lines-- > 0) {
#if (CONFIG_ARC_MMU_VER > 2)
/*
* Just as for I$, in MMU v3, D$ ops also require
* "tag" bits in DC_PTAG, "index" bits in FLDL,IVDL ops
*/
write_aux_reg(ARC_REG_DC_PTAG, paddr);

write_aux_reg(aux, vaddr);
vaddr += L1_CACHE_BYTES;
#else
/* paddr contains stuffed vaddrs bits */
write_aux_reg(aux, paddr);
#endif
paddr += L1_CACHE_BYTES;
}
}

/* For kernel mappings cache operation: index is same as paddr */
#define __dc_line_op_k(p, sz, op) __dc_line_op(p, p, sz, op)

Expand All @@ -362,7 +366,7 @@ static inline void __dc_line_op(unsigned long paddr, unsigned long vaddr,
write_aux_reg(ARC_REG_DC_CTRL, tmp | DC_CTRL_INV_MODE_FLUSH);
}

__dc_line_loop(paddr, vaddr, sz, cacheop);
__cache_line_loop(paddr, vaddr, sz, cacheop);

if (cacheop & OP_FLUSH) /* flush / flush-n-inv both wait */
wait_for_flush();
Expand Down Expand Up @@ -434,42 +438,9 @@ static void __ic_line_inv_vaddr(unsigned long paddr, unsigned long vaddr,
unsigned long sz)
{
unsigned long flags;
int num_lines;

/*
* Ensure we properly floor/ceil the non-line aligned/sized requests:
* However page sized flushes can be compile time optimised.
* -@paddr will be cache-line aligned already (being page aligned)
* -@sz will be integral multiple of line size (being page sized).
*/
if (!(__builtin_constant_p(sz) && sz == PAGE_SIZE)) {
sz += paddr & ~CACHE_LINE_MASK;
paddr &= CACHE_LINE_MASK;
vaddr &= CACHE_LINE_MASK;
}

num_lines = DIV_ROUND_UP(sz, L1_CACHE_BYTES);

#if (CONFIG_ARC_MMU_VER <= 2)
/* bits 17:13 of vaddr go as bits 4:0 of paddr */
paddr |= (vaddr >> PAGE_SHIFT) & 0x1F;
#endif

local_irq_save(flags);
while (num_lines-- > 0) {
#if (CONFIG_ARC_MMU_VER > 2)
/* tag comes from phy addr */
write_aux_reg(ARC_REG_IC_PTAG, paddr);

/* index bits come from vaddr */
write_aux_reg(ARC_REG_IC_IVIL, vaddr);
vaddr += L1_CACHE_BYTES;
#else
/* paddr contains stuffed vaddrs bits */
write_aux_reg(ARC_REG_IC_IVIL, paddr);
#endif
paddr += L1_CACHE_BYTES;
}
__cache_line_loop(paddr, vaddr, sz, OP_INV_IC);
local_irq_restore(flags);
}

Expand Down

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