From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 11856 invoked by alias); 3 Nov 2012 15:31:33 -0000 Received: (qmail 11842 invoked by uid 22791); 3 Nov 2012 15:31:32 -0000 X-SWARE-Spam-Status: No, hits=-0.8 required=5.0 tests=AWL,BAYES_00,KHOP_RCVD_UNTRUST,KHOP_THREADED,RCVD_IN_DNSWL_LOW,RISK_FREE X-Spam-Check-By: sourceware.org Received: from hagrid.ecoscentric.com (HELO mail.ecoscentric.com) (212.13.207.197) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Sat, 03 Nov 2012 15:31:25 +0000 Received: from localhost (hagrid.ecoscentric.com [127.0.0.1]) by mail.ecoscentric.com (Postfix) with ESMTP id D9AA12F78010 for ; Sat, 3 Nov 2012 15:31:23 +0000 (GMT) Received: from mail.ecoscentric.com ([127.0.0.1]) by localhost (hagrid.ecoscentric.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id ZtzzF5eLUvtX; Sat, 3 Nov 2012 15:31:19 +0000 (GMT) From: bugzilla-daemon@bugs.ecos.sourceware.org To: ecos-bugs@ecos.sourceware.org Subject: [Bug 1001606] Enable the cache on Kinetis in RAM startup mode X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: eCos X-Bugzilla-Component: HAL X-Bugzilla-Keywords: X-Bugzilla-Severity: enhancement X-Bugzilla-Who: ilijak@siva.com.mk X-Bugzilla-Status: NEEDINFO X-Bugzilla-Priority: low X-Bugzilla-Assigned-To: jifl@ecoscentric.com X-Bugzilla-Target-Milestone: --- X-Bugzilla-Changed-Fields: Attachment #1966 is obsolete Attachment #1967 is obsolete In-Reply-To: References: X-Bugzilla-URL: http://bugs.ecos.sourceware.org/ Auto-Submitted: auto-generated Content-Type: text/plain; charset="UTF-8" MIME-Version: 1.0 Date: Sat, 03 Nov 2012 15:31:00 -0000 Message-Id: <20121103153119.6E8952F78005@mail.ecoscentric.com> Mailing-List: contact ecos-bugs-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Post: List-Help: , Sender: ecos-bugs-owner@sourceware.org X-SW-Source: 2012/txt/msg01324.txt.bz2 Please do not reply to this email. Use the web interface provided at: http://bugs.ecos.sourceware.org/show_bug.cgi?id=1001606 Ilija Kocho changed: What |Removed |Added ---------------------------------------------------------------------------- Attachment #1966|0 |1 is obsolete| | Attachment #1967|0 |1 is obsolete| | --- Comment #36 from Ilija Kocho 2012-11-03 15:31:16 GMT --- Created an attachment (id=1973) --> (http://bugs.ecos.sourceware.org/attachment.cgi?id=1973) Kinetis variant - separate DCACHE-ICACHE 121103 (In reply to comment #35) > Finally I reply.... Many thanks... > > First of all, to follow up a specific question you asked: > > (In reply to comment #25) > > (In reply (addendum) to comment #23) > > > > > Bus arbitration tweak for copy-back DDRAM 121008 > > > > > > > Another consideration: It is possible to swap PC and PS priorities permanently > > for RAM startup. Then cache control macros will be shorter and there's no risk > > of preemption.. The drawback, if any, is that crossbar arbitration priorities > > for DDRAM will be different than the reset default. If implemented, this > > inversion could be fixed or configurable with CDL. > > Comments? > > I don't have a very good feel for what the effects of this would be. > Specifically, can you imagine a situation when someone really would want the PC > priority to be higher than the PS one? I can't see it making a big difference > either way in the end, so I'm thinking a permanent change would be ok (although > if so, why wasn't it the reset default?). If PC priority is lower there shouldn't be danger of stale since soon after instruction fetch is pre-empted by data access (from previous instruction), it will cause the data transfer to seize (previous instruction ends) that will unblock instruction fetch. Therefore, the set-up where PC has lower priority than PS looks inherently more stable than the opposite. However, I assume that it is most probable for users to expect reset-default priorities upon start-up so I have left them unchanged. Also I can imagine situation where user has set up PC higher priority then PS - then the protective macro will be still necessary. > > As for the main patches.... I'm glad that the split cache scheme has made such > a great improvement in measured performance, as per our private email exchange. > It shows it was worth the effort! Indeed. I redid the tests and new results for old scheme are not as low (now I have used different mirror, but there's still 30% boost. > > One thing that strikes me as odd is the addition of CYG_HAL_STARTUP_DEF_ROM to > define CYG_HAL_STARTUP_ROM for RAM startup types. This seems potentially risky. > What problem was it intended to solve? It shouldn't be there :(. I t is a ghost from my test to use technique from FLASH start-up [Bug 1001623] - ROM start-up emulation. It was working but copying initialized data from RAM to RAM makes little sense. Actually this cdl_option was removed, but somehow re-appeared. Now I have removed (patch attached) it again and retested everything. > > Other than that, I've reviewed everything already written in this issue, and > been through the current patches, and I don't see any reason not to commit the > patches. There might be a few essentially cosmetic things (spelling, typos, > etc.) that I could change, but minor touch-ups like that can be done after the > commit rather than going round the loop again. > So now I am going to commit, but I will leave this bug open for a while as a reminder. Thanks again Ilija -- Configure bugmail: http://bugs.ecos.sourceware.org/userprefs.cgi?tab=email ------- You are receiving this mail because: ------- You are on the CC list for the bug.