From ab61f7d21ab7f564fce322c498e4a7d6171140db Mon Sep 17 00:00:00 2001 From: Haavard Skinnemoen Date: Mon, 18 Jun 2007 14:08:18 +0200 Subject: [PATCH] [AVR32] Fix bug in invalidate_dcache_region() If (start + size) is not cacheline aligned and (start & mask) > (end & mask), the last but one cacheline won't be invalidated as it should. Fix this by rounding `end' down to the nearest cacheline boundary if it gets adjusted due to misalignment. Also flush the write buffer unconditionally -- if the dcache wrote back a line just before we invalidated it, the dirty data may be sitting in the write buffer waiting to corrupt our buffer later. Signed-off-by: Haavard Skinnemoen --- arch/avr32/mm/cache.c | 14 +++++--------- 1 file changed, 5 insertions(+), 9 deletions(-) diff --git a/arch/avr32/mm/cache.c b/arch/avr32/mm/cache.c index 8f7b1c3cd0f9..c1233c615e67 100644 --- a/arch/avr32/mm/cache.c +++ b/arch/avr32/mm/cache.c @@ -23,7 +23,6 @@ void invalidate_dcache_region(void *start, size_t size) { unsigned long v, begin, end, linesz, mask; - int flush = 0; linesz = boot_cpu_data.dcache.linesz; mask = linesz - 1; @@ -32,24 +31,21 @@ void invalidate_dcache_region(void *start, size_t size) * instead of invalidating ... never discard valid data! */ begin = (unsigned long)start; - end = begin + size - 1; + end = begin + size; if (begin & mask) { flush_dcache_line(start); begin += linesz; - flush = 1; } - if ((end & mask) != mask) { + if (end & mask) { flush_dcache_line((void *)end); - end -= linesz; - flush = 1; + end &= ~mask; } /* remaining cachelines only need invalidation */ - for (v = begin; v <= end; v += linesz) + for (v = begin; v < end; v += linesz) invalidate_dcache_line((void *)v); - if (flush) - flush_write_buffer(); + flush_write_buffer(); } void clean_dcache_region(void *start, size_t size) -- 2.20.1