aboutsummaryrefslogtreecommitdiffstats
path: root/arch/tile/include/asm/cacheflush.h
diff options
context:
space:
mode:
Diffstat (limited to 'arch/tile/include/asm/cacheflush.h')
-rw-r--r--arch/tile/include/asm/cacheflush.h52
1 files changed, 52 insertions, 0 deletions
diff --git a/arch/tile/include/asm/cacheflush.h b/arch/tile/include/asm/cacheflush.h
index c5741da4eeac..14a3f8556ace 100644
--- a/arch/tile/include/asm/cacheflush.h
+++ b/arch/tile/include/asm/cacheflush.h
@@ -137,4 +137,56 @@ static inline void finv_buffer(void *buffer, size_t size)
mb_incoherent();
}
+/*
+ * Flush & invalidate a VA range that is homed remotely on a single core,
+ * waiting until the memory controller holds the flushed values.
+ */
+static inline void finv_buffer_remote(void *buffer, size_t size)
+{
+ char *p;
+ int i;
+
+ /*
+ * Flush and invalidate the buffer out of the local L1/L2
+ * and request the home cache to flush and invalidate as well.
+ */
+ __finv_buffer(buffer, size);
+
+ /*
+ * Wait for the home cache to acknowledge that it has processed
+ * all the flush-and-invalidate requests. This does not mean
+ * that the flushed data has reached the memory controller yet,
+ * but it does mean the home cache is processing the flushes.
+ */
+ __insn_mf();
+
+ /*
+ * Issue a load to the last cache line, which can't complete
+ * until all the previously-issued flushes to the same memory
+ * controller have also completed. If we weren't striping
+ * memory, that one load would be sufficient, but since we may
+ * be, we also need to back up to the last load issued to
+ * another memory controller, which would be the point where
+ * we crossed an 8KB boundary (the granularity of striping
+ * across memory controllers). Keep backing up and doing this
+ * until we are before the beginning of the buffer, or have
+ * hit all the controllers.
+ */
+ for (i = 0, p = (char *)buffer + size - 1;
+ i < (1 << CHIP_LOG_NUM_MSHIMS()) && p >= (char *)buffer;
+ ++i) {
+ const unsigned long STRIPE_WIDTH = 8192;
+
+ /* Force a load instruction to issue. */
+ *(volatile char *)p;
+
+ /* Jump to end of previous stripe. */
+ p -= STRIPE_WIDTH;
+ p = (char *)((unsigned long)p | (STRIPE_WIDTH - 1));
+ }
+
+ /* Wait for the loads (and thus flushes) to have completed. */
+ __insn_mf();
+}
+
#endif /* _ASM_TILE_CACHEFLUSH_H */