On Tue, Jun 16, 2020 at 03:18:02PM +0200, Tomek The Messenger wrote: > Hi > I am in the middle of implementation of various external kernel modules. > All kernel modules touch some board specific registers. For example let's > say we have 3 groups of register areas: > #define REG1_ADDR (0xFDEA7000) > #define REG1 _SIZE (0x3C0) > #define REG2_ADDR (0xFDEC4000) > #define REG2 _SIZE (0xFF8) > #define REG3_ADDR (0xFDEA6000) > #define REG3_SIZE (0x80) > And let's say we have 5 kernel modules: > A > B > C > D > E > > Kernel module A touches only one 32-bit register X from REG1 space and a > lot of registers from REG2 space. > Kernel modules B,C,D touches various registers from REG1 and REG2 space but > not this one which kernel module A touches. > Kernel module E is the only one who touches registers from REG3 space. No > other kernel module touches REG3 space. > > If I would implement the code in C++ in user space I would create dynamic > library for access to REG1,REG2,REG3 register space. Each 32-bit register > would have his own separate function to read,write to register. And then > each user space process A-E would be linked against this library during > compilation. > When programming in kernel I don't know what I should do. > Should I implement 6th external kernel module which implements all > operations on access to registers REG1,REG2,REG3??? There will be a lot of > EXPORT_SYMBOL_GPL. Or maybe this approach is NOK, I mean it is good but I > should only place in 6th helper kernel module functions which are used by > more than one kernel module. So for example functions for getting access to > REG3 address space or reg X from REG1 space should be not there. They > should be only in kernel module code A/E. Currently this is code which I > implemented. In 6th helper kernel module there are only registers which are > used by more than one kernel module. But I am not sure if it is good > approach. Maybe there should be there all registers access? > > Could anybody help how to organize code here. Why is this so many different modules? Why not just make it one? thanks, greg k-h _______________________________________________ Kernelnewbies mailing list Kernelnewbies@xxxxxxxxxxxxxxxxx https://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
