H. Peter Anvin wrote:
Followup to: <[email protected]>
By author: Deepak Saxena <[email protected]>
In newsgroup: linux.dev.kernel
It's a magic regsiter we just read/write and could be done in userspace.
I also took a look at MPC85xx and it has the same sort of interface but
also has an error interrupt capability. On second thought a class
interface is overkill b/c there will only be one RNG per system, so
I can just do something like watchdogs where we have a bunch of simple
drivers exposing the same interface. We could do it in user space but
then we have separate RNG implementations for x86 and !x86 and I'd
rather not see that. Can we move the x86 code out to userspace and
just let the daemon eat the numbers directly from HW? We can mmap()
PCI devices, but I don't know enough about x86 to say whether msr
instructions can execute out of userspace (or if we want them to...).
MSR instructions cannot execute out of userspace, but the MSR driver
might be possible to use. It's usually quite slow, however.
MSRs are used for setup, not for actual data.
Intel: magic MMIO address (readb)
AMD: magic PIO address (inl)
VIA: CPU instruction ('xstore')
Jeff
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
[Index of Archives]
[Kernel Newbies]
[Netfilter]
[Bugtraq]
[Photo]
[Stuff]
[Gimp]
[Yosemite News]
[MIPS Linux]
[ARM Linux]
[Linux Security]
[Linux RAID]
[Video 4 Linux]
[Linux for the blind]
[Linux Resources]
