On Thu, Mar 26, 2009 at 4:27 PM, Wolfgang Denk wd@denx.de wrote:
Dear Jon Smirl,
In message 9e4733910903260647w549a97acv7101ea9347a767bb@mail.gmail.com you wrote:
My networking hardware needs microcode loaded into it before it will function. What's the best method to load this code? It's 70KB.
My current u-boot image is 170KB. I started working with the code in examples and api_examples. But the "hello world" programs built using those APIs are 65-72KB in size. That's almost half the size of my u-boot image and these programs just print "hello world". Why are these programs so big? My goal was to put the loader program and my microcode into a single 128KB erase block.
My code for loading the microcode into the hardware is 7KB. Now it looks like I will need to incorporate it into the main u-boot image instead of making it an external command.
I'm not sure how you calculate sizes, or how you link your applications. Note that classical standalone application do not link against any libraries, so they are really small:
The *.bin files are ending up at 60-75K. Adding this to the linker script fixes it. .gcc_except_table : ONLY_IF_RO { KEEP (*(.gcc_except_table)) *(.gcc_except_table.*) }
Approximately 60KB of zeros are getting inserted into the *.bin files.
Before: jonsmirl@terra:/home/apps/u-boot/examples$ ls *.bin -l -rwxr-xr-x 1 jonsmirl jonsmirl 66424 2009-03-26 15:59 hello_world.bin -rwxr-xr-x 1 jonsmirl jonsmirl 66460 2009-03-26 15:59 interrupt.bin -rwxr-xr-x 1 jonsmirl jonsmirl 68464 2009-03-26 15:59 sched.bin
After the linker script change: jonsmirl@terra:/home/apps/u-boot/examples$ ls *.bin -l -rwxr-xr-x 1 jonsmirl jonsmirl 4136 2009-03-26 16:49 hello_world.bin -rwxr-xr-x 1 jonsmirl jonsmirl 4128 2009-03-26 16:49 interrupt.bin -rwxr-xr-x 1 jonsmirl jonsmirl 4184 2009-03-26 16:49 sched.bin jonsmirl@terra:/home/apps/u-boot/examples$
-> size examples/{hello_world,timer} text data bss dec hex filename 796 40 0 836 344 examples/hello_world 1556 56 0 1612 64c examples/timer
As you can see, the "hello world" demo program just needs a few hundret bytes.
Best regards,
Wolfgang Denk
-- DENX Software Engineering GmbH, MD: Wolfgang Denk & Detlev Zundel HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd@denx.de The computer can't tell you the emotional story. It can give you the exact mathematical design, but what's missing is the eyebrows.
- Frank Zappa