len0rd/rockbox
1
0
Fork 1
mirror of https://github.com/Rockbox/rockbox.git synced 2025-12-07 13:45:03 -05:00
Code Issues Projects Releases Packages Wiki Activity Actions

mi4: replace chksum_crc32 with crc_32r

Browse source 
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
This commit is contained in:
James Buren 2021-06-21 09:36:54 +00:00
parent fc92081080
commit 581081a3df
8 changed files with 6 additions and 147 deletions
Download patch file Download diff file Expand all files Collapse all files

5
firmware/target/arm/pp/mi4-loader.c
View file

@ -27,12 +27,11 @@
#include "config.h"
#include "mi4-loader.h"
#include "loader_strerror.h"
#include "crc32-mi4.h"
#include "crc32.h"
#include "file.h"
#if defined(HAVE_BOOTDATA)
#include "system.h"
#include "bootdata.h"
#include "crc32.h"
/* Write bootdata into location in FIRMWARE marked by magic header
* Assumes buffer is already loaded with the firmware image
@ -293,7 +292,7 @@ static int load_mi4_filename(unsigned char* buf,
return EREAD_IMAGE_FAILED;
/* 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);
if(sum != mi4header.crc32)
return EBAD_CHKSUM;