initial push

m683xx/bdm-driver/README

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+This version of BDM driver is updated to be compatible with
+the most of existing kernel versions. Main focus has been oriented
+to 2.2.x and 2.4.x, but most of other unstable and stable kernels
+back to 1.3.x stone age should be supported.
+
+Driver needs to find kernel sources to compile.
+You may need to edit "Makefile-mod" for some strange kernel
+sources locations. There is automatic location selection depending
+on current kernel version and "/lib/modules" structure.
+It select next kernel souces directory for older kernels
+
+  KERNEL_LOCATION=/usr/src/linux
+
+it uses more reliable way of build process for
+new modules hierarchy
+
+  KERNEL_LOCATION=/lib/modules/$(CURRENT)/build
+
+*** BDM driver autoloading ***
+
+No longer su to root, insmod the module of choice, and then start the
+debugger as user-joe, but just start the debugger, and the necessary
+modules get loaded automatically.
+
+What do you have to do?
+    * You need to copy the device driver code to
+        /lib/modules/<kernel-version>/misc
+      for 2.4.0 kernels use 
+        /lib/modules/<kernel-version>/kernel/drivers/char
+    * edit /etc/conf.modules 
+        (see my local /etc/conf.modules as an example)
+    * do a "depmod -a".
+    * Start "kerneld" at an early boot stage 
+      or enable "kmod" in kernel configuration in section
+      "Loadable module support".
+
+For more details on dynamic kernel module support, see the READMEs
+in the latest modules utilities. The current release is modutils-2.4.22.
+
+*** IMPORTANT ***
+
+The bdm driver checks if the required resources (here only the io-port 
+addresses) are in use, e.g. by the lp device driver or a parallel port 
+ethernet device. When everything is free, it reserves these resources, and
+releases them when closing the device. So no double access should be possible.
+
+If BDM driver is compiled without PARPORT support, there could be problem
+with "parport", "parport_pc" and "lp" module stack resource reservation,
+which could compete with "m683xx-bdm" driver. Compile "lp" and "parport"
+as modules in such case and unload them before "m683xx-bdm".
+Opposite is true in the case of BDM driver with PARPORT support.
+You need "parport_pc" compiled into kernel or as module.
+
+Possibilities reworded
+
+A) You need to rmmod parport, if you have compiled BDM driver WITHOUT parport
+   support. It  can be done by next line added to "/etc/modules.conf"
+
+	pre-install   bdm /sbin/modprobe -r lp parport_pc
+	    
+B) If BDM driver is compiled WITH parport support, the "parport_pc" module
+   have to be loaded before "bdm" one. It is loaded by boot process in the
+   most cases but next line in "/etc/modules.conf" doe not hurt
+		    
+	below bdm parport_pc
+
+** DEVFS support ***
+
+Driver supports new "devfs" virtual device filesystem found in
+2.4.0 kernels. There are compiled-in next device names for those
+kenels "/dev/m683xx-bdm/pd0" and "/dev/m683xx-bdm/icd0" etc.
+
+You can add next line to "/etc/devfs.conf"
+
+  LOOKUP	m683xx-bdm	MODLOAD
+
+Next line helps to connect simple "/dev/bdm" name for right configuration
+
+  LOOKUP	m683xx-bdm	EXECUTE /bin/ln -s ${mntpnt}/m683xx-bdm/icd0 ${mntpnt}/m683xx-bdm
+
+There are lines for "/dev/modules.conf" with aliases for different kernels
+
+  # m68k BDM
+  alias	/dev/bdm        m683xx-bdm
+  alias	/dev/m683xx-bdm m683xx-bdm
+  alias	char-major-53   m683xx-bdm
+  # the next line is required/usable for BDM driver compiled without
+  # parport support. You might want to remove this line if you get errors
+  # about unresolved symbols when the driver is loaded.
+  pre-install	m683xx-bdm /sbin/modprobe -r lp parport_pc
+