Date: Wed, 19 May 1999 11:08:06 +0200 (MET DST) From: John K <john@volvo.se> To: "Ronald 'Ko' Klop" <ronald@node11a94.a2000.nl> Cc: freebsd-questions@freebsd.org Subject: Re: Cyrix 486 kernel options Message-ID: <Pine.BSD/.3.91.990519110011.812A-100000@nike.volvo.se> In-Reply-To: <Pine.BSF.4.05.9905182300490.1228-100000@dlanor.evertsen.nl>
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Hi If i remeber corrctly, the 486DX has an internal FPU (Floating Point=20 Unit or...whatever) and the entire 486 series does (except for maybe the SX= ) Feel free to correct me if i=B4m wrong here. Im more familiar with Intel chips. the 80386 had a separate Co Math=20 Processor (FPU) called 80387, and it was about the same size as the CPU :) maybe Cyrix used external IBM FPU=B4s ? anyway, on a DX i don=B4t think you need this option. br john On Tue, 18 May 1999, Ronald 'Ko' Klop wrote: Hello, >=20 > FreeBSD 3.1-RELEASE reports this as my CPU: >=20 > CPU: Cyrix 486DX (486-class CPU) > Origin =3D "CyrixInstead" DIR=3D0x031a Stepping=3D0 Revision=3D3 >=20 > In the LINT-configuration are the following options: >=20 > # CPU_BLUELIGHTNING_FPU_OP_CACHE enables FPU operand cache on IBM > # BlueLightning CPU. It works only with Cyrix FPU, and this option > # should not be used with Intel FPU. >=20 > # CPU_DIRECT_MAPPED_CACHE sets L1 cache of Cyrix 486DLC CPU in direct > # mapped mode. Default is 2-way set associative mode. >=20 > # CYRIX_CACHE_WORKS enables CPU cache on Cyrix 486 CPUs with cache > # flush at hold state. > # > # CYRIX_CACHE_REALLY_WORKS enables (1) CPU cache on Cyrix 486 CPUs > # without cache flush at hold state, and (2) write-back CPU cache on > # Cyrix 6x86 whose revision < 2.7 (NOTE 2). >=20 > What is the BlueLightning CPU? Do I need this option? > How do I know if I have a 486DLC? (Or will FreeBSD report this?) >=20 > And how do I determine if my CPU has cache flush at hold state or not? > Which of these options should I use? Or shouldn't I use them? >=20 > Thanks in advance, >=20 > Ronald. >=20 >=20 > --=20 > Ronald Klop > http://node11a94.a2000.nl/~ronald/ >=20 >=20 >=20 > To Unsubscribe: send mail to majordomo@FreeBSD.org > with "unsubscribe freebsd-questions" in the body of the message >=20 To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message
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