From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <44169813.6020007@domain.hid> Date: Tue, 14 Mar 2006 11:16:51 +0100 From: Jan Kiszka MIME-Version: 1.0 Subject: Re: [Xenomai-core] RTDM and Timer functions References: <200603091443.25714.lbocseg@domain.hid> <200603131431.35216.lbocseg@domain.hid> <4415BB0D.8070808@domain.hid> <200603131631.26195.lbocseg@domain.hid> <4415FAC5.7050608@domain.hid> <44167BE9.2090703@domain.hid> In-Reply-To: <44167BE9.2090703@domain.hid> Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="------------enigA4E11D423276E3A531455103" Sender: jan.kiszka@domain.hid List-Id: "Xenomai life and development \(bug reports, patches, discussions\)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Anders Blomdell Cc: xenomai-core This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --------------enigA4E11D423276E3A531455103 Content-Type: text/plain; charset=ISO-8859-15 Content-Transfer-Encoding: quoted-printable Anders Blomdell wrote: > Jan Kiszka wrote: >> ... >> Thinking about this more thoroughly, a few questions popped up for me:= >> >> o When we call it rtdm_clock_read_tsc(), we should actually return the= >> raw TSC values, shouln't we? But then we also need conversion >> functions (rtdm_clock_tsc2ns, rtdm_clock_ns2tsc). Or should we alway= s >> convert to nanoseconds on return? POSIX and Native are different in >> this regard. >> >> o What would be the core rationale behind it, having a high-resolution= >> time stamp? What are the primary use cases? I'm asking for this so >> that I can clearly differentiate between this new service and the >> existing one in the docs. Also, giving an abstract description would= >> leave more options to the actual implementation on other archs or >> platforms. > If you implement it, don't forget to point out that the tsc may have > increments varying over time (due to clock scaling), and might even sto= p > for long periods (ACPI sleep), just so we are not faced with a primitiv= e > that makes it impossible to implement low-power operation (not at the > very top on my priority list, but still important). Yeah, one reason why I'm hesitating ATM to introduce a too specific service to RTDM. But I'm still open to being persuaded about its usefulne= ss. Jan --------------enigA4E11D423276E3A531455103 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.2 (MingW32) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iD8DBQFEFpgUniDOoMHTA+kRAil4AJsHkAAJOVPlDZc5Jt0emgrtd5hJbACeNCzr jwA/hK12eCkuZWHBIs1umIM= =pj6r -----END PGP SIGNATURE----- --------------enigA4E11D423276E3A531455103--