[U-Boot] [PATCH] bootvx: use program header for loading

[Christian Gmeiner]

Hi Bin

2018-03-21 14:14 GMT+01:00 Bin Meng <bmeng.cn at gmail.com>:
> Hi Christian,
>
> On Tue, Mar 20, 2018 at 9:18 PM, Christian Gmeiner
> <christian.gmeiner at gmail.com> wrote:
>> The section header address is a VMA whereas the address found in
>> the program header is a physical one. With this change it is
>> possible to load and start a vx7 intel generic based image.
>>
>> $ readelf -l /tmp/vx7
>>
>> Elf file type is EXEC (Executable file)
>> Entry point 0x408000
>> There are 2 program headers, starting at offset 52
>>
>> Program Headers:
>>   Type           Offset   VirtAddr   PhysAddr   FileSiz MemSiz  Flg Align
>>   LOAD           0x001000 0x00408000 0x00408000 0x04000 0x04000 RWE 0x1000
>>   LOAD           0x005000 0xe040c000 0x0040c000 0x583a84 0x5ccc70 RWE 0x1000
>>
>>  Section to Segment mapping:
>>   Segment Sections...
>>    00     .text.locore .data.locore
>>    01     .text .eh_frame .wrs_build_vars .data .tls_data .tls_vars .bss
>>
>> $ readelf -S /tmp/vx7
>> There are 13 section headers, starting at offset 0x588af8:
>>
>> Section Headers:
>>   [Nr] Name              Type            Addr     Off    Size   ES Flg Lk Inf Al
>>   [ 0]                   NULL            00000000 000000 000000 00      0   0  0
>>   [ 1] .text.locore      PROGBITS        00408000 001000 00011e 00  AX  0   0 16
>>   [ 2] .data.locore      PROGBITS        00409000 002000 003000 00  WA  0   0 4096
>>   [ 3] .text             PROGBITS        e040c000 005000 4802a0 00 WAX  0   0 32
>>   [ 4] .eh_frame         PROGBITS        e088c2a0 4852a0 0a1ed0 00   A  0   0  4
>>   [ 5] .wrs_build_vars   PROGBITS        e092e170 527170 000190 00  Ax  0   0  1
>>   [ 6] .data             PROGBITS        e092f000 528000 060a70 00  WA  0   0 4096
>>   [ 7] .tls_data         PROGBITS        e098fa70 588a70 000004 00   A  0   0  4
>>   [ 8] .tls_vars         PROGBITS        e098fa78 588a78 00000c 00  WA  0   0  4
>>   [ 9] .bss              NOBITS          e098faa0 588a84 0491d0 00  WA  0   0 32
>>   [10] .shstrtab         STRTAB          00000000 588a84 000074 00      0   0  1
>>   [11] .symtab           SYMTAB          00000000 588d00 056ee0 10     12 9758  4
>>   [12] .strtab           STRTAB          00000000 5dfbe0 05f48a 00      0   0  1
>> Key to Flags:
>>   W (write), A (alloc), X (execute), M (merge), S (strings)
>>   I (info), L (link order), G (group), T (TLS), E (exclude), x (unknown)
>>   O (extra OS processing required) o (OS specific), p (processor specific)
>>
>> For completeness here are the same information for an old vx5 based image. After
>> this change it is possible to boot vx5 and vx7 (intel generic) images.
>>
>> $ readelf -l /tmp/vx5
>>
>> Elf file type is EXEC (Executable file)
>> Entry point 0x308000
>> There are 1 program headers, starting at offset 52
>>
>> Program Headers:
>>  Type           Offset   VirtAddr   PhysAddr   FileSiz MemSiz  Flg Align
>>  LOAD           0x000060 0x00308000 0x00308000 0x3513a0 0x757860 RWE 0x20
>>
>> Section to Segment mapping:
>>  Segment Sections...
>>   00     .text .data .bss
>> [christian at chgm-pc ~]$ readelf -S /tmp/vx5
>> There are 12 section headers, starting at offset 0x356580:
>>
>> Section Headers:
>>  [Nr] Name              Type            Addr     Off    Size   ES Flg Lk Inf Al
>>  [ 0]                   NULL            00000000 000000 000000 00      0   0  0
>>  [ 1] .text             PROGBITS        00308000 000060 319b10 00 WAX  0   0 32
>>  [ 2] .data             PROGBITS        00621b20 319b80 037880 00  WA  0   0 32
>>  [ 3] .bss              NOBITS          006593a0 351400 4064c0 00  WA  0   0 16
>>  [ 4] .debug_aranges    PROGBITS        00000000 351400 000060 00      0   0  1
>>  [ 5] .debug_pubnames   PROGBITS        00000000 351460 00018b 00      0   0  1
>>  [ 6] .debug_info       PROGBITS        00000000 3515eb 003429 00      0   0  1
>>  [ 7] .debug_abbrev     PROGBITS        00000000 354a14 000454 00      0   0  1
>>  [ 8] .debug_line       PROGBITS        00000000 354e68 0016a4 00      0   0  1
>>  [ 9] .shstrtab         STRTAB          00000000 35650c 000071 00      0   0  1
>>  [10] .symtab           SYMTAB          00000000 356760 0440e0 10     11 8574  4
>>  [11] .strtab           STRTAB          00000000 39a840 03e66c 00      0   0  1
>> Key to Flags:
>>  W (write), A (alloc), X (execute), M (merge), S (strings)
>>  I (info), L (link order), G (group), T (TLS), E (exclude), x (unknown)
>>  O (extra OS processing required) o (OS specific), p (processor specific)
>>
>> Signed-off-by: Christian Gmeiner <christian.gmeiner at gmail.com>
>> ---
>>  cmd/elf.c | 2 +-
>>  1 file changed, 1 insertion(+), 1 deletion(-)
>>
>
> Thanks for the patch. Did you verify booting a VxWorks 6.x kernel?

Sadly no as I do not have any working vx6 image for the hw.

> Last time I tested 'bootvx' was on Intel Galileo board with VxWorks 7.
> I will find some time to test this patch.
>

Wonderful.

-- 
greets
--
Christian Gmeiner, MSc

https://christian-gmeiner.info