In message: <20080128211803.GA20434@xxxxxxxxxxxxxx>
Ralf Baechle <ralf@xxxxxxxxxxxxxx> writes:
: On Mon, Jan 28, 2008 at 02:02:45PM -0700, M. Warner Losh wrote:
:
: > : this specific interaction of ABI and processor architecture then it was
: > : probably found not to implement such a special read because it is messy
: > : in more than one way.
: >
: > When 64-bit operations are enabled, you get all 64-bits. When they
: > aren't, only the lower 32-bits of the counter are provided (with sign
: > extension). So when operating in 32-bit mode, saving the upper 32
: > bits are not necessary (or even possible).
:
: The architecture manual doesn't make a difference between 32-bit and
: 64-bit for rdhwr. My reading is the entire 64-bit would have to be
: transfered.
Hmmm, the manual I have specifically calls out the difference...
Has cavium provided a public version?
Warner
