On 10/08/2017 05:06 PM, Hauke Mehrtens wrote: > The boot process on a WRT54GL works the following way: > 1. CFE gets loaded by the boot rom from flash > 2. CFE loads the loader from the flash and gzip uncompresses it > 3. CFE starts the loader > 4. The loader stores the FW arguments and relocates itself to > BZ_TEXT_START (now 0x80600000) > 5. The loader reads the Linux image from flash > 6. The loader lzma decompresses the Linux image to LOADADDR (0x80001000) > 7. The loader executes the uncompress Linux image at LOADADDR > > The BZ_TEXT_START was set to 0x80400000 before. When the kernel gets > uncompressed and is bigger than BZ_TEXT_START - LOADADDR it overwrote > the loader which was currently uncompressing it and made the board > crash. Increase the BZ_TEXT_START my 2 MB to have more space for the > kernel. Even on 16MB RAM devices the memory goes till 0x80FFFFFF so this > should not be a problem. > > Signed-off-by: Hauke Mehrtens <ha...@hauke-m.de> > --- > target/linux/brcm47xx/image/lzma-loader/src/Makefile | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/target/linux/brcm47xx/image/lzma-loader/src/Makefile > b/target/linux/brcm47xx/image/lzma-loader/src/Makefile > index 3320e565d0..444039c558 100644 > --- a/target/linux/brcm47xx/image/lzma-loader/src/Makefile > +++ b/target/linux/brcm47xx/image/lzma-loader/src/Makefile > @@ -18,7 +18,7 @@ > # > > TEXT_START := 0x80001000 > -BZ_TEXT_START := 0x80400000 > +BZ_TEXT_START := 0x80600000 > > OBJCOPY := $(CROSS_COMPILE)objcopy -O binary -R .reginfo -R > .note -R .comment -R .mdebug -S
This makes my WRT54GS boot a kernel 4.9 with CONFIG_KALLSYMS. Without this patch it is not booting up. The FW arguments are more or less useless, I got these in Linux from CFE forwarded by the loader: fw_arg0: 0x803401a0, fw_arg1: 0x0, fw_arg2: 0x803029c8, fw_arg3: 0x43464531 They are pointing somewhere into CFE: Total memory used by CFE: 0x80300000 - 0x8043DF30 (1302320) Initialized Data: 0x803381A0 - 0x8033A550 (9136) BSS Area: 0x8033A550 - 0x8033BF30 (6624) Local Heap: 0x8033BF30 - 0x8043BF30 (1048576) Stack Area: 0x8043BF30 - 0x8043DF30 (8192) Text (code) segment: 0x80300000 - 0x803381A0 (229792) Boot area (physical): 0x0043E000 - 0x0047E000 Relocation Factor: I:00000000 - D:00000000 See section 8.2.3 "Registers passed to boot loaders" for details on what these arguments mean: http://melbourne.wireless.org.au/files/wrt54/cfe.pdf Our image does not use them anyway so this is also save. Hauke _______________________________________________ Lede-dev mailing list Lede-dev@lists.infradead.org http://lists.infradead.org/mailman/listinfo/lede-dev
