From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:52185) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1SCu1A-00005a-Oe for qemu-devel@nongnu.org; Wed, 28 Mar 2012 10:38:38 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1SCu10-0001Kc-VL for qemu-devel@nongnu.org; Wed, 28 Mar 2012 10:38:32 -0400 Received: from mail-pb0-f45.google.com ([209.85.160.45]:36394) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1SCu10-0001KE-MZ for qemu-devel@nongnu.org; Wed, 28 Mar 2012 10:38:22 -0400 Received: by pbcuo5 with SMTP id uo5so2167889pbc.4 for ; Wed, 28 Mar 2012 07:38:20 -0700 (PDT) From: Andrew Towers Date: Thu, 29 Mar 2012 01:37:28 +1100 Message-Id: <1332945448-31266-1-git-send-email-atowers@gmail.com> Subject: [Qemu-devel] [PATCH] ARM: Permit any ARMv6K CPU to read the MVFR0 and MVFR1 VFP registers. List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Peter Maydell , Paul Brook , Andrew Towers From: Andrew Towers Replaces the ARM_FEATURE_VFP3 check when reading MVFR0/1 with a check for ARM_FEATURE_V6K. Rationale: MVFR0/1 were introduced in the ARM1136 at the same time as ARMv6K, and a survey of TRMs indicates support in later models. According to reference documentation on arm.com, MVFR0 and MVFR1 were introduced in ARM1136JF-S r1p1 (ARMv6K, VFPv2). They are also present in ARM1156T2F-S and ARM1176JZF-S, which contain VFP11 r5, and in ARM11 MPCore r1 which contains VFP11 r4. Reference (ARM DDI 0211H, 0290G, 0301H, 0360E) http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.ddi0211h/Ffbefjag.html Without this change, the linux kernel will not boot with VFP support enabled under ARM1176 system emulation, due to the unconditional use of MVFR1 at the end of vfp_init() in arch/arm/vfp/vfpmodule.c in the kernel: VFP support v0.3: implemetor 41 architecture 1 part 20 variant b rev 5 Internal error: Oops - undefined instruction: 0 [#1] Yes, I am slightly abusing the versatilepb hw emulation, but then so is everyone else in the world who is still waiting for their Raspberry Pi ;) Signed-off-by: Andrew Towers --- target-arm/translate.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/target-arm/translate.c b/target-arm/translate.c index 81725d1..b5861c8 100644 --- a/target-arm/translate.c +++ b/target-arm/translate.c @@ -2906,7 +2906,7 @@ static int disas_vfp_insn(CPUARMState * env, DisasContext *s, uint32_t insn) case ARM_VFP_MVFR0: case ARM_VFP_MVFR1: if (IS_USER(s) - || !arm_feature(env, ARM_FEATURE_VFP3)) + || !arm_feature(env, ARM_FEATURE_V6K)) return 1; tmp = load_cpu_field(vfp.xregs[rn]); break; -- 1.7.5.4