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parisc: Don't enforce DMA completion order in cache flushes

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The only place we need to ensure all outstanding cache coherence
operations are complete is in invalidate_kernel_vmap_range. All
parisc drivers synchronize DMA operations internally and do not
call invalidate_kernel_vmap_range. We only need this for non-coherent
I/O operations.

Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
This commit is contained in:
John David Anglin 2022-03-30 14:42:30 +00:00 committed by Helge Deller
parent 41dc0b53bc
commit 1fc7db2401
3 changed files with 4 additions and 3 deletions
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1
arch/parisc/include/asm/cache.h
View file

@ -54,6 +54,7 @@ void parisc_setup_cache_timing(void);
#define asm_io_sync() asm volatile("sync" \
ALTERNATIVE(ALT_COND_NO_DCACHE, INSN_NOP) \
ALTERNATIVE(ALT_COND_NO_IOC_FDC, INSN_NOP) :::"memory")
#define asm_syncdma() asm volatile("syncdma" :::"memory")
#endif /* ! __ASSEMBLY__ */

3
arch/parisc/kernel/cache.c
View file

@ -754,6 +754,9 @@ void invalidate_kernel_vmap_range(void *vaddr, int size)
unsigned long start = (unsigned long)vaddr;
unsigned long end = start + size;
/* Ensure DMA is complete */
asm_syncdma();
if ((!IS_ENABLED(CONFIG_SMP) || !arch_irqs_disabled()) &&
(unsigned long)size >= parisc_cache_flush_threshold) {
flush_tlb_kernel_range(start, end);

3
arch/parisc/kernel/pacache.S
View file

@ -300,7 +300,6 @@ fdoneloop2:
fdce,m %arg1(%sr1, %arg0) /* Fdce for one loop */
fdsync:
syncdma
sync
mtsm %r22 /* restore I-bit */
89: ALTERNATIVE(88b, 89b, ALT_COND_NO_DCACHE, INSN_NOP)
@ -1098,7 +1097,6 @@ ENTRY_CFI(flush_kernel_dcache_range_asm)
sync
89: ALTERNATIVE(88b, 89b, ALT_COND_NO_DCACHE, INSN_NOP)
syncdma
bv %r0(%r2)
nop
ENDPROC_CFI(flush_kernel_dcache_range_asm)
@ -1140,7 +1138,6 @@ ENTRY_CFI(purge_kernel_dcache_range_asm)
sync
89: ALTERNATIVE(88b, 89b, ALT_COND_NO_DCACHE, INSN_NOP)
syncdma
bv %r0(%r2)
nop
ENDPROC_CFI(purge_kernel_dcache_range_asm)