# HG changeset patch
# User a1ex
# Date 1394617354 -7200
#      Wed Mar 12 11:42:34 2014 +0200
# Branch raw-alignment
# Node ID fc84146a6a40094738cff32a47dc57b413198406
# Parent  e86afc9f2c41864eb59dd302713ea1cffc20345a
raw_rec/mlv_rec/edmac: make sure the EDMAC line width is always multiple of 8 bytes (should fix crashes at fastest EDMAC flags, e.g. on 6D, not tested)

diff -r e86afc9f2c41 -r fc84146a6a40 modules/mlv_rec/mlv_rec.c
--- a/modules/mlv_rec/mlv_rec.c	Mon Mar 10 12:51:05 2014 +0200
+++ b/modules/mlv_rec/mlv_rec.c	Wed Mar 12 11:42:34 2014 +0200
@@ -113,8 +113,10 @@
 uint32_t raw_rec_trace_ctx = TRACE_ERROR;
 static uint32_t abort_test = 0;
 /**
- * resolution should be multiple of 16 horizontally
- * see http://www.magiclantern.fm/forum/index.php?topic=5839.0
+ * resolution (in pixels) should be multiple of 16 horizontally (see http://www.magiclantern.fm/forum/index.php?topic=5839.0)
+ * furthermore, resolution (in bytes) should be multiple of 8 in order to use the fastest EDMAC flags ( http://magiclantern.wikia.com/wiki/Register_Map#EDMAC ),
+ * which copy 16 bytes at a time, but only check for overflows every 8 bytes (can be verified experimentally)
+ * => if my math is not broken, this traslates to resolution being multiple of 32 pixels horizontally
  * use roughly 10% increments
  **/
 
@@ -524,7 +526,9 @@
     int32_t left_margin = (raw_info.active_area.x1 + 7) / 8 * 8;
     int32_t right_margin = (raw_info.active_area.x2) / 8 * 8;
     int32_t max = (right_margin - left_margin) & ~15;
-    while (max % 16) max--;
+
+    /* horizontal resolution *MUST* be mod 32 in order to use the fastest EDMAC flags (16 byte transfer) */
+    while (max % 32) max--;
     max_res_x = max;
 
     /* max res Y */
diff -r e86afc9f2c41 -r fc84146a6a40 modules/raw_rec/raw_rec.c
--- a/modules/raw_rec/raw_rec.c	Mon Mar 10 12:51:05 2014 +0200
+++ b/modules/raw_rec/raw_rec.c	Wed Mar 12 11:42:34 2014 +0200
@@ -88,8 +88,10 @@
 static int cam_60d = 0;
 
 /**
- * resolution should be multiple of 16 horizontally
- * see http://www.magiclantern.fm/forum/index.php?topic=5839.0
+ * resolution (in pixels) should be multiple of 16 horizontally (see http://www.magiclantern.fm/forum/index.php?topic=5839.0)
+ * furthermore, resolution (in bytes) should be multiple of 8 in order to use the fastest EDMAC flags ( http://magiclantern.wikia.com/wiki/Register_Map#EDMAC ),
+ * which copy 16 bytes at a time, but only check for overflows every 8 bytes (can be verified experimentally)
+ * => if my math is not broken, this traslates to resolution being multiple of 32 pixels horizontally
  * use roughly 10% increments
  **/
 
@@ -291,7 +293,9 @@
     int left_margin = (raw_info.active_area.x1 + 7) / 8 * 8;
     int right_margin = (raw_info.active_area.x2) / 8 * 8;
     int max = (right_margin - left_margin) & ~15;
-    while (max % 16) max--;
+    
+    /* horizontal resolution *MUST* be mod 32 in order to use the fastest EDMAC flags (16 byte transfer) */
+    while (max % 32) max--;
     max_res_x = max;
     
     /* max res Y */
diff -r e86afc9f2c41 -r fc84146a6a40 src/edmac-memcpy.c
--- a/src/edmac-memcpy.c	Mon Mar 10 12:51:05 2014 +0200
+++ b/src/edmac-memcpy.c	Wed Mar 12 11:42:34 2014 +0200
@@ -119,6 +119,12 @@
 
 void* edmac_copy_rectangle_cbr_start(void* dst, void* src, int src_width, int src_x, int src_y, int dst_width, int dst_x, int dst_y, int w, int h, void (*cbr_r)(void*), void (*cbr_w)(void*), void *cbr_ctx)
 {
+    /* dmaFlags are set up for 16 bytes per transfer, and overflow checking seems to be done every 8 bytes */
+    /* widths that are not modulo 8 will cause overflow (the DMA will not stop) */
+    /* do not remove this check, or risk permanent camera bricking */
+    if (dst_width % 8)
+        return 0;
+
     take_semaphore(edmac_memcpy_sem, 0);
     
     /* see wiki, register map, EDMAC what the flags mean. they are for setting up copy block size */
@@ -199,7 +207,7 @@
 void* edmac_copy_rectangle_adv(void* dst, void* src, int src_width, int src_x, int src_y, int dst_width, int dst_x, int dst_y, int w, int h)
 {
     void* ans = edmac_copy_rectangle_adv_start(dst, src, src_width, src_x, src_y, dst_width, dst_x, dst_y, w, h);
-    edmac_copy_rectangle_adv_finish();
+    if (ans) edmac_copy_rectangle_adv_finish();
     return ans;
 }