Hi Barry. I think the toolchain is operating correctly here. The current version recognises a divide followed by a modulo and optimises this into a call to the standard EABI function __aeabi__uldivmod(). Note the code:
do_div(Kpart, source);
K = Kpart & 0xFFFFFFFF;
/* Check if we need to round */ if ((K % 10) >= 5) K += 5;
This function is provided by libgcc for normal applications. The kernel provides it's own versions in arch/arm/lib/lib1funcs.s but is missing __aeabi_uldivmod (note the 'l' for 64 bit).
-- Michael
On Tue, Apr 26, 2011 at 12:45 AM, Barry Song 21cnbao@gmail.com wrote:
Hi All, I am using 2011.3 4.5 linaro GCC(armv7-a vfpv3d16) to compile kernel and modules. I select to compile all codecs as modules: "config SND_SOC_ALL_CODECS tristate "Build all ASoC CODEC drivers" " as M and I2C/SPI too.
Then in the kernel dir, run "make" to get both vmlinux and modules, I found snd-soc-wm8974.ko, snd-soc-wm8940.ko and snd-soc-wm8510.ko will fail due to "__aeabi_uldivmod undefined".
If i comment do_div() in these codec drivers, this issue will disappear. But it is strange there are many codecs which use do_div() too, for example: sound/soc/codecs/max98088.c sound/soc/codecs/max9850.c sound/soc/codecs/wm8350.c sound/soc/codecs/wm8400.c sound/soc/codecs/wm8510.c sound/soc/codecs/wm8580.c sound/soc/codecs/wm8753.c sound/soc/codecs/wm8804.c sound/soc/codecs/wm8900.c sound/soc/codecs/wm8904.c sound/soc/codecs/wm8940.c sound/soc/codecs/wm8955.c sound/soc/codecs/wm8960.c sound/soc/codecs/wm8974.c sound/soc/codecs/wm8978.c sound/soc/codecs/wm8985.c sound/soc/codecs/wm8990.c sound/soc/codecs/wm8991.c sound/soc/codecs/wm8993.c sound/soc/codecs/wm8994.c sound/soc/codecs/wm8995.c sound/soc/codecs/wm9081.c
but others can pass the compiling except those 3 modules. Is it due to a wrong optimization by gcc?
Other information:
- old tool-chains we are using can pass the compiling of the 3 modules.
- If i built all codecs into kernel image, these 3 drivers don't
report error while compiling.
Thanks Barry
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