| Message ID | 1296766349-4695-1-git-send-email-alexander.stein@informatik.tu-chemnitz.de |
|---|---|
| State | Accepted |
| Commit | 6087f1a90cb2f275752496229b96f0e00aa0a7cd |
| Delegated to: | Albert ARIBAUD |
| Headers | show |
Hi Alexander, Le 03/02/2011 21:52, Alexander Stein a écrit : > Signed-off-by: Alexander Stein<alexander.stein@informatik.tu-chemnitz.de> > --- > Hello, > > I just played a bit with my at91sam9g20ek and tried using a new u-boot. > So I compiled 656b990daa84bfdd512407ee2e3d2610e305a455 (atmel/wip110202) load > it into memory using jtag to 0x22000000 while it was linked to 0x20000000. Side note: loading and starting U-Boot at an address different from the one which it was linked for is not currently supported. > I stepped through the relocation code and at start.S:291 'mov pc, lr' the pc > gets an invalid address (0x25F81D70 while memory ends at 0x24000000). > While stepping to start.S:286 some registers have the following contents: > r0: 00000d70 > r1: 22000000 > r9: 03f81000 > lr: 22000d70 > The content if r0 seems ok, but r1 seems wrong, it should be 0x20000000. > Indeed r1 should contain the linked address of _start not the address > relative from the current code. Correct, since we're trying to find the post-relocation address of board_init_r, we should add the relocation offet to its link-time address, not run-time address -- the fact that both are the same right now is only incidental. Thus: Applied to u-boot-arm, thanks. Amicalement,
diff --git a/arch/arm/cpu/arm926ejs/start.S b/arch/arm/cpu/arm926ejs/start.S index eb93ac9..f4c177e 100644 --- a/arch/arm/cpu/arm926ejs/start.S +++ b/arch/arm/cpu/arm926ejs/start.S @@ -281,7 +281,7 @@ _nand_boot_ofs: .word nand_boot #else ldr r0, _board_init_r_ofs - adr r1, _start + ldr r1, _TEXT_BASE add lr, r0, r1 add lr, lr, r9 /* setup parameters for board_init_r */
Signed-off-by: Alexander Stein <alexander.stein@informatik.tu-chemnitz.de> --- Hello, I just played a bit with my at91sam9g20ek and tried using a new u-boot. So I compiled 656b990daa84bfdd512407ee2e3d2610e305a455 (atmel/wip110202) load it into memory using jtag to 0x22000000 while it was linked to 0x20000000. I stepped through the relocation code and at start.S:291 'mov pc, lr' the pc gets an invalid address (0x25F81D70 while memory ends at 0x24000000). While stepping to start.S:286 some registers have the following contents: r0: 00000d70 r1: 22000000 r9: 03f81000 lr: 22000d70 The content if r0 seems ok, but r1 seems wrong, it should be 0x20000000. Indeed r1 should contain the linked address of _start not the address relative from the current code. Just for the records, here is the output of u-boot while DEBUG is set in board.c: U-Boot 2010.12-00322-g656b990-dirty (Feb 03 2011 - 20:40:07) U-Boot code: 20000000 -> 2002DAE8 BSS: -> 2006EE80 CPU: AT91SAM9G20 Crystal frequency: 18.432 MHz CPU clock : 396.288 MHz Master clock : 132.096 MHz monitor len: 0006EE80 ramsize: 04000000 TLB table at: 23ff0000 Top of RAM usable for U-Boot at: 23ff0000 Reserving 443k for U-Boot at: 23f81000 Reserving 644k for malloc() at: 23ee0000 Reserving 24 Bytes for Board Info at: 23edffe8 Reserving 144 Bytes for Global Data at: 23edff58 New Stack Pointer is: 23edff50 RAM Configuration: Bank #0: 20000000 64 MiB relocation Offset is: 03f81000 If I load u-boot to the linking address (no relocation needed), everything works fine, obviously. Best regards, Alexander arch/arm/cpu/arm926ejs/start.S | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-)