Date: Man, 12 Apr 2004 12:21:44 +0200 skrev Axel Weiss <[email protected]> :
>Ok, maybe there's some misunderstanding due to copy-n-paste-mistakes
>I made in my former mail.
>
>As I suppose my device drivers will not become part of the official
>kernel, I
>keep them with my project. My opinion now is to use one Makefile for
>both,
>2.2-2.4 and 2.6 kernels, and to keep this Makefile simple.
I have never looked at 2.2 so here I cannot help you.
But my original questions remains:
Why you cannot use the same Makefile for 2.4 and 2.6?
A simple Makefile like you outline:
>EXTRA_CFLAGS := -I/usr/include
>obj-m += <my_module>.o
><my_module>-objs = <my module object files>
Will work flawlessly with both 2.4 and 2.6.
I know people for a long time have hardcoded the gcc commandline
to build modules for 2.4 - but thats just wrong.
In this way you do not catch differences in gcc options.
For 2.4 we have seen only few of these config related flags to gcc,
in 2.6 we have a lot.
Please next time post the full Makefile.
Btw, a module that is dependent on /usr/include looks wrong...
I have no knowledge of a documented way to distingush between 2.4
and 2.6 in the Makefiles.
>Maybe, I'm not the first one who tries this, or maybe others would
>find it
>useful - that's the reason why I want to discuss this topic here.
>(If I'm OT,
>please let me know).
Not OT - please continue.
>
>all:
> $(MAKE) -C $(KDIR) SUBDIRS=$(PWD) modules
>
>clean:
> rm -f *.o *.ko .*.cmd <my_module>.mod.c
For the new external module support implemented in -mc4 you
do not have to hardcode the clean: target, and no attempts will
be made to update the kernel stuff.
Documentation soon to arrive...
Sam
Am Montag, 12. April 2004 15:20 schrieb [email protected]:
> Date: Man, 12 Apr 2004 12:21:44 +0200 skrev Axel Weiss <[email protected]> :
> Why you cannot use the same Makefile for 2.4 and 2.6?
On SuSE-9.0 the build simply fails:
rantanplan:/home/axel/freeSP-1.0.3 # make -C drivers/linux/harmonie/
make: Entering directory `/home/axel/freeSP-1.0.3/drivers/linux/harmonie'
make -C driver all
make[1]: Entering directory `/home/axel/freeSP-1.0.3/drivers/linux/harmonie/driver'
make -C /lib/modules/2.4.21-199-axel/build SUBDIRS=/home/axel/freeSP-1.0.3/drivers/linux/harmonie/driver modules
make[2]: Entering directory `/usr/src/linux-2.4.21-199'
make -C /home/axel/freeSP-1.0.3/drivers/linux/harmonie/driver CFLAGS="-D__KERNEL__ -I/usr/src/linux-2.4.21-199/include -Wall -Wstrict-prototypes -Wno-trigraphs -O2 -fno-strict-aliasing -fno-common -fomit-frame-pointer -fno-unit-at-a-time -pipe -msoft-float -mpreferred-stack-boundary=2 -march=athlon -DMODULE" MAKING_MODULES=1 modules
make[3]: Entering directory `/home/axel/freeSP-1.0.3/drivers/linux/harmonie/driver'
make[3]: *** Keine Regel, um ?modules? zu erstellen. Schluss.
make[3]: Leaving directory `/home/axel/freeSP-1.0.3/drivers/linux/harmonie/driver'
make[2]: *** [_mod_/home/axel/freeSP-1.0.3/drivers/linux/harmonie/driver] Fehler 2
make[2]: Leaving directory `/usr/src/linux-2.4.21-199'
make[1]: *** [all] Fehler 2
make[1]: Leaving directory `/home/axel/freeSP-1.0.3/drivers/linux/harmonie/driver'
make: *** [module] Fehler 2
make: Leaving directory `/home/axel/freeSP-1.0.3/drivers/linux/harmonie'
>
> A simple Makefile like you outline:
> >EXTRA_CFLAGS := -I/usr/include
> >obj-m += <my_module>.o
> ><my_module>-objs = <my module object files>
>
> Will work flawlessly with both 2.4 and 2.6.
> I know people for a long time have hardcoded the gcc commandline
> to build modules for 2.4 - but thats just wrong.
> In this way you do not catch differences in gcc options.
> For 2.4 we have seen only few of these config related flags to gcc,
> in 2.6 we have a lot.
>
> Please next time post the full Makefile.
(see eom)
>
> Btw, a module that is dependent on /usr/include looks wrong...
This is because I include the ioctl-definitions, and I put them to /usr/include/dsp, so the kernel module and user-space-lib see the identical file.
Perhaps it would be better to include the local source (in this case ../system_include), I will think over it.
> >clean:
> > rm -f *.o *.ko .*.cmd <my_module>.mod.c
>
> For the new external module support implemented in -mc4 you
> do not have to hardcode the clean: target, and no attempts will
> be made to update the kernel stuff.
> Documentation soon to arrive...
Do you think, it would be better to write
clean:
$(MAKE) -C $(KDIR) SUBDIRS=$(PWD) clean
?
There are still some inconsistencies, especially when I try to compile a second module. I will investigate this tonight and post cognitions here.
The next problem arises when I have to ditinguish the kernel version within C source. For now I do it like this:
// fw-declaration of /proc-read functions:
#ifdef LINUX_VERSION_CODE
#if LINUX_VERSION_CODE <= KERNEL_VERSION(2, 4, 18)
int harmonie_read_proc(char *buf, char **start, off_t offset, int len, int unused);
#else // 2.4.19 ... < 2.5
int harmonie_read_proc(char *buf, char **start, off_t offset, int cnt, int *eof, void *data);
#endif
#else // >= 2.5
int harmonie_read_proc(char *buf, char **start, off_t offset, int cnt, int *eof, void *data);
#endif
This looks really ugly, so what is the recommended way to get kernel version information? As the interface for ISRs has changed, too, there is a need for getting kernel version at compile time.
For now, I have a running module for 2.2 - 2.6 :)
Now the complete Makefile:
# ***************************************************************************
# makefile - description
#
# This is the harmonie device driver makefile.
#
# -------------------
# begin : Wed May 29 2002
# copyright : (C) 2002 by Axel Weiss
# email : [email protected]
# ***************************************************************************/
#
# ***************************************************************************
# * *
# * This program is free software; you can redistribute it and/or modify *
# * it under the terms of the GNU General Public License as published by *
# * the Free Software Foundation; either version 2 of the License, or *
# * (at your option) any later version. *
# * *
# ***************************************************************************/
KERNELVERSION := $(shell uname -r)
KERNELBASE := $(basename $(KERNELVERSION))
KERNELMINOR := $(suffix $(KERNELBASE))
KERNELMAJOR := $(basename $(KERNELBASE))
OLD_MODULES := $(strip $(foreach V, .0 .1 .2 .3 .4, $(shell [ "$(V)" = "$(KERNELMINOR)" ] && echo yes)))
ifeq ($(KERNELMAJOR),2)
ifeq ($(OLD_MODULES),yes) # old style make
DEBUG := yes
CC := gcc
SOURCES := $(wildcard *.c)
HEADERS := $(wildcard *.h)
OBJS := $(SOURCES:%.c=%.o)
CC_FLAGS := -c -Wall -I/lib/modules/`uname -r`/build/include -DMODULE -D__KERNEL__
ifeq ($(DEBUG),yes)
CC_FLAGS += -DHARMONIE_DEBUG
endif
all: harmonie.o
harmonie.o: $(OBJS)
$(LD) -r -o $@ $(OBJS)
$(OBJS): %.o:%.c
$(CC) $(CC_FLAGS) $<
$(OBJS): $(HEADERS) $(SYSTEM_HEADERS_INSTALL)
clean:
@rm -f $(OBJS) *% *.bak harmonie.o
else #ifeq ($(OLD_MODULES),yes) new style make
ifneq ($(KERNELRELEASE),)
EXTRA_CFLAGS := -I/usr/include
obj-m += harmonie.o
harmonie-objs = harmonie_buffer.o harmonie_device.o harmonie_module.o harmonie_procio.o harmonie_io.o
else #ifneq ($(KERNELRELEASE),)
KDIR := /lib/modules/$(shell uname -r)/build
PWD := $(shell pwd)
all:
$(MAKE) -C $(KDIR) SUBDIRS=$(PWD) modules
clean:
rm -f *.o *.ko .*.cmd harmonie.mod.c
endif #ifneq ($(KERNELRELEASE),)
endif #ifeq ($(OLD_MODULES),yes)
else #ifeq ($(KERNELMAJOR),2) # kernel 1.x ?
all:
@echo kernel $(KERNELVERSION) not supported
endif #ifeq ($(KERNELMAJOR),2)