mi4: replace chksum_crc32 with crc_32r

This uses an equivalent algorithm but with a different initial value
than we normally use (all bits off vs all bits on). Use the new crc_32r
to replace the original MI4 crc32 implementation.

This frees up some extra space on mi4 targets which gives us more
room on a few very space constrained targets (sansa c200/e200, etc).

Change-Id: Iaaac3ae353b30566156b1404cbf31ca32926203d

3 files changed, 4 insertions, 5 deletions

diff --git a/bootloader/fat32format.c b/bootloader/fat32format.c
index 540ee89b54..a885a5fced 100644
--- a/bootloader/fat32format.c
+++ b/bootloader/fat32format.c
@@ -44,7 +44,6 @@
 #include "storage.h"
 #include "button.h"
 #include "disk.h"
-#include "crc32-mi4.h"
 #include <string.h>
 #include "i2c.h"
 #include "backlight-target.h"
diff --git a/bootloader/main-e200r-installer.c b/bootloader/main-e200r-installer.c
index 5d1bff7b37..63b3fcb142 100644
--- a/bootloader/main-e200r-installer.c
+++ b/bootloader/main-e200r-installer.c
@@ -35,7 +35,7 @@
 #include "file.h"
 #include "button.h"
 #include "disk.h"
-#include "crc32-mi4.h"
+#include "crc32.h"
 #include <string.h>
 #include "i2c.h"
 #include "backlight-target.h"
@@ -138,7 +138,7 @@ void* main(void)
 
     storage_read_sectors(pinfo.start + START_SECTOR_OF_ROM + ROMSECTOR_TO_HACK,
                          1 , sector);
-    crc32 = chksum_crc32 (sector, 512);
+    crc32 = crc_32r (sector, 512, 0);
 
 #if 0 /* not needed in release builds */
     printf("--- Hack Status ---");
diff --git a/bootloader/main-pp.c b/bootloader/main-pp.c
index ef766455b6..08b5ea3ef5 100644
--- a/bootloader/main-pp.c
+++ b/bootloader/main-pp.c
@@ -37,7 +37,7 @@
 #include "adc.h"
 #include "button.h"
 #include "disk.h"
-#include "crc32-mi4.h"
+#include "crc32.h"
 #include "mi4-loader.h"
 #include "loader_strerror.h"
 #include <string.h>
@@ -169,7 +169,7 @@ int load_mi4_part(unsigned char* buf, struct partinfo* pinfo,
                         (mi4header.mi4size-MI4_HEADER_SIZE)/512, buf);
 
     /* Check CRC32 to see if we have a valid file */
-    sum = chksum_crc32 (buf,mi4header.mi4size-MI4_HEADER_SIZE);
+    sum = crc_32r (buf,mi4header.mi4size-MI4_HEADER_SIZE,0);
 
     printf("Calculated CRC32: %x", sum);