Add cache flush operations for CRISv32.
These are needed due to a cache bug, and can be used to make sure
that the DMA descriptors are flushed to memory and can be safely
handled by DMA.
flush_dma_descr - Flush one DMA descriptor.
flush_dma_list - Flush a complete list of DMA descriptors.
cris_flush_cache - Flush the complete cache.
cris_flush_cache_range - Flush only the specified range
Signed-off-by: Jesper Nilsson <[EMAIL PROTECTED]>
---
cache.c | 33 ++++++++++++++++++++
cacheflush.S | 94 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 127 insertions(+)
diff --git a/arch/cris/arch-v32/kernel/cache.c
b/arch/cris/arch-v32/kernel/cache.c
new file mode 100644
index 0000000..80da7b8
--- /dev/null
+++ b/arch/cris/arch-v32/kernel/cache.c
@@ -0,0 +1,33 @@
+#include <linux/module.h>
+#include <asm/io.h>
+#include <asm/arch/cache.h>
+#include <asm/arch/hwregs/dma.h>
+
+/* This file is used to workaround a cache bug, Guinness TR 106. */
+
+inline void flush_dma_descr(struct dma_descr_data *descr, int flush_buf)
+{
+ /* Flush descriptor to make sure we get correct in_eop and after. */
+ asm volatile ("ftagd [%0]" :: "r" (descr));
+ /* Flush buffer pointed out by descriptor. */
+ if (flush_buf)
+ cris_flush_cache_range(phys_to_virt((unsigned)descr->buf),
+ (unsigned)(descr->after - descr->buf));
+}
+EXPORT_SYMBOL(flush_dma_descr);
+
+void flush_dma_list(struct dma_descr_data *descr)
+{
+ while (1) {
+ flush_dma_descr(descr, 1);
+ if (descr->eol)
+ break;
+ descr = phys_to_virt((unsigned)descr->next);
+ }
+}
+EXPORT_SYMBOL(flush_dma_list);
+
+/* From cacheflush.S */
+EXPORT_SYMBOL(cris_flush_cache);
+/* From cacheflush.S */
+EXPORT_SYMBOL(cris_flush_cache_range);
diff --git a/arch/cris/arch-v32/kernel/cacheflush.S
b/arch/cris/arch-v32/kernel/cacheflush.S
new file mode 100644
index 0000000..956e8fb
--- /dev/null
+++ b/arch/cris/arch-v32/kernel/cacheflush.S
@@ -0,0 +1,94 @@
+ .global cris_flush_cache_range
+cris_flush_cache_range:
+ move.d 1024, $r12
+ cmp.d $r11, $r12
+ bhi cris_flush_1KB
+ nop
+ add.d $r10, $r11
+ ftagd [$r10]
+cris_flush_last:
+ addq 32, $r10
+ cmp.d $r11, $r10
+ blt cris_flush_last
+ ftagd [$r10]
+ ret
+ nop
+cris_flush_1KB:
+ ftagd [$r10]
+ addq 32, $r10
+ ftagd [$r10]
+ addq 32, $r10
+ ftagd [$r10]
+ addq 32, $r10
+ ftagd [$r10]
+ addq 32, $r10
+ ftagd [$r10]
+ addq 32, $r10
+ ftagd [$r10]
+ addq 32, $r10
+ ftagd [$r10]
+ addq 32, $r10
+ ftagd [$r10]
+ addq 32, $r10
+ ftagd [$r10]
+ addq 32, $r10
+ ftagd [$r10]
+ addq 32, $r10
+ ftagd [$r10]
+ addq 32, $r10
+ ftagd [$r10]
+ addq 32, $r10
+ ftagd [$r10]
+ addq 32, $r10
+ ftagd [$r10]
+ addq 32, $r10
+ ftagd [$r10]
+ addq 32, $r10
+ ftagd [$r10]
+ addq 32, $r10
+ ftagd [$r10]
+ addq 32, $r10
+ ftagd [$r10]
+ addq 32, $r10
+ ftagd [$r10]
+ addq 32, $r10
+ ftagd [$r10]
+ addq 32, $r10
+ ftagd [$r10]
+ addq 32, $r10
+ ftagd [$r10]
+ addq 32, $r10
+ ftagd [$r10]
+ addq 32, $r10
+ ftagd [$r10]
+ addq 32, $r10
+ ftagd [$r10]
+ addq 32, $r10
+ ftagd [$r10]
+ addq 32, $r10
+ ftagd [$r10]
+ addq 32, $r10
+ ftagd [$r10]
+ addq 32, $r10
+ ftagd [$r10]
+ addq 32, $r10
+ ftagd [$r10]
+ addq 32, $r10
+ ftagd [$r10]
+ addq 32, $r10
+ ftagd [$r10]
+ addq 32, $r10
+ ba cris_flush_cache_range
+ sub.d $r12, $r11
+
+ .global cris_flush_cache
+cris_flush_cache:
+ moveq 0, $r10
+cris_flush_line:
+ move.d 16*1024, $r11
+ addq 16, $r10
+ cmp.d $r10, $r11
+ blt cris_flush_line
+ fidxd [$r10]
+ ret
+ nop
/^JN - Jesper Nilsson
--
Jesper Nilsson -- [EMAIL PROTECTED]
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [EMAIL PROTECTED]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
