Coldfire: Optimize emac context save/restore in mixer ISR.

Save only once if emac is used in ISR and restore only once per ISR
call if already saved.

Change-Id: I0e40db5d4aab2a8552480f76873f59ff6ccd9977
Reviewed-on: http://gerrit.rockbox.org/176
Tested-by: Michael Sevakis <jethead71@rockbox.org>
Reviewed-by: Michael Sevakis <jethead71@rockbox.org>

1 files changed, 3 insertions, 0 deletions

diff --git a/firmware/pcm_mixer.c b/firmware/pcm_mixer.c
index 9077c6f271..00891f367d 100644
--- a/firmware/pcm_mixer.c
+++ b/firmware/pcm_mixer.c
@@ -232,6 +232,9 @@ fill_frame:
         *downmix_buf[downmix_index] = downmix_index ? 0x7fff7fff : 0x80008000;
 #endif
 
+    /* Certain SoC's have to do cleanup */
+    mixer_buffer_callback_exit();
+
     return PCM_DMAST_OK;
 }