common: bouncebuf: Permit passing custom alignment check function

Add extended version of the bounce_buffer_start(), which permits passing in
a custom alignment checker function for the buffer. This is useful e.g. on
systems with various DMA restrictions and where the checker function might
be more complex than a simple CPU cache alignment check.

Signed-off-by: Marek Vasut <marek.vasut+renesas@gmail.com>
Cc: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Peng Fan <peng.fan@nxp.com>
Cc: Simon Glass <sjg@chromium.org>
Cc: Tom Rini <trini@konsulko.com>

diff --git a/common/bouncebuf.c b/common/bouncebuf.c
index 614eb36c7856ef87969a9d769f5e2bcd250ecb9c..0ace152b98e0b5e6729796ad18625cc3804ac29a 100644 (file)
--- a/common/bouncebuf.c
+++ b/common/bouncebuf.c
@@ -31,17 +31,19 @@ static int addr_aligned(struct bounce_buffer *state)
        return 1;
 }
 
-int bounce_buffer_start(struct bounce_buffer *state, void *data,
-                       size_t len, unsigned int flags)
+int bounce_buffer_start_extalign(struct bounce_buffer *state, void *data,
+                                size_t len, unsigned int flags,
+                                size_t alignment,
+                                int (*addr_is_aligned)(struct bounce_buffer *state))
 {
        state->user_buffer = data;
        state->bounce_buffer = data;
        state->len = len;
-       state->len_aligned = roundup(len, ARCH_DMA_MINALIGN);
+       state->len_aligned = roundup(len, alignment);
        state->flags = flags;
 
-       if (!addr_aligned(state)) {
-               state->bounce_buffer = memalign(ARCH_DMA_MINALIGN,
+       if (!addr_is_aligned(state)) {
+               state->bounce_buffer = memalign(alignment,
                                                state->len_aligned);
                if (!state->bounce_buffer)
                        return -ENOMEM;
@@ -62,6 +64,14 @@ int bounce_buffer_start(struct bounce_buffer *state, void *data,
        return 0;
 }
 
+int bounce_buffer_start(struct bounce_buffer *state, void *data,
+                       size_t len, unsigned int flags)
+{
+       return bounce_buffer_start_extalign(state, data, len, flags,
+                                           ARCH_DMA_MINALIGN,
+                                           addr_aligned);
+}
+
 int bounce_buffer_stop(struct bounce_buffer *state)
 {
        if (state->flags & GEN_BB_WRITE) {

diff --git a/include/bouncebuf.h b/include/bouncebuf.h
index fd9b0f3b289535ea4274c851ce91b22ad80b88be..7427bd12e27c29d114e605387bd7f024505a5f0e 100644 (file)
--- a/include/bouncebuf.h
+++ b/include/bouncebuf.h
@@ -62,6 +62,21 @@ struct bounce_buffer {
  */
 int bounce_buffer_start(struct bounce_buffer *state, void *data,
                        size_t len, unsigned int flags);
+
+/**
+ * bounce_buffer_start() -- Start the bounce buffer session with external align check function
+ * state:      stores state passed between bounce_buffer_{start,stop}
+ * data:       pointer to buffer to be aligned
+ * len:                length of the buffer
+ * flags:      flags describing the transaction, see above.
+ * alignment:  alignment of the newly allocated bounce buffer
+ * addr_is_aligned: function for checking the alignment instead of the default one
+ */
+int bounce_buffer_start_extalign(struct bounce_buffer *state, void *data,
+                                size_t len, unsigned int flags,
+                                size_t alignment,
+                                int (*addr_is_aligned)(struct bounce_buffer *state));
+
 /**
  * bounce_buffer_stop() -- Finish the bounce buffer session
  * state:      stores state passed between bounce_buffer_{start,stop}