Date: Sun, 2 Jun 2024 18:37:44 +0200 From: tuexen@freebsd.org To: Robert Clausecker <fuz@freebsd.org> Cc: freebsd-riscv@freebsd.org, Mitchell Horne <mhorne@freebsd.org>, strajabot@gmail.com Subject: Re: Detecting the Zbb extension on riscv64 Message-ID: <232F8595-5C7A-4ABD-961D-4779CED5A5D6@freebsd.org> In-Reply-To: <Zlx2u52Xw7Aw6svM@fuz.su> References: <ZlxZn5IQuQ-zqbwl@fuz.su> <5343E09C-017B-40B7-9349-01F1195BBB7C@freebsd.org> <Zlx2u52Xw7Aw6svM@fuz.su>
next in thread | previous in thread | raw e-mail | index | archive | help
> On 2. Jun 2024, at 15:42, Robert Clausecker <fuz@freebsd.org> wrote: >=20 > Hi Michael, >=20 > Am Sun, Jun 02, 2024 at 03:05:09PM +0200 schrieb tuexen@freebsd.org: >>> Zbb is supported by the SiFive unmatched board for example. >> just double checking: >> According to >> = https://sifive.cdn.prismic.io/sifive/d0556df9-55c6-47a8-b0f2-4b1521546543_= hifive-unmatched-datasheet.pdf >> the processor supports RV64GC (RV64IMAFDC). I don't see a B there. >> So does it actually support Zbb? What about Zbr? >=20 > The board is based on the SiFive FU740-C000 SoC, which uses > a quad-core U74 CPU. Reading the [U74 Core Complex Manual], > we find that it supports the Zba and Zbb instruction set > extensions. >=20 > [U74 Core Complex Manual]: = https://starfivetech.com/uploads/u74_core_complex_manual_21G1.pdf Thanks for the pointer. Zbr is not mentioned there... >=20 > Though on the other hand, if I actually try to execute a program > using the CTZ instruction, I get a SIGILL... what's going on here? I don't know. Best regards Michael >=20 > Yours, > Robert Clausecker >=20 > --=20 > () ascii ribbon campaign - for an encoding-agnostic world > /\ - against html email - against proprietary attachments >=20
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?232F8595-5C7A-4ABD-961D-4779CED5A5D6>