From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 6FC64C0218A for ; Thu, 30 Jan 2025 22:59:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=TubmSrwRi/TCfWi2WGQBNH4XIGRnJUjKLSO17age/XE=; b=G+2inD9aGfPaUs UNwHIXnTyVs/tdRZDETrPXb++t1kc59e+7a7fC1r5cCdLGqWdTAqxOJQVsPvnSIqY7E2YgUqCP478 Ha0ynaJHEdKEn5ICj4GE2/WgOdboxP5ckF1xOM6WDj5a4gVX9PvqWDzX3qc/ooZ+U4c7EYMvHxk6h XIfkSJAGjWALfqhnBgH8YAS09aRUlqD3NOqFpIg5b2Q9hjJoHwpYFM5P/oSvpufdFrjVL6xWGARIC IMclpTqMC9cpVq2qGa4QCxfGKeTlX0gqp+4Aw3XW0+zC2XikeZQMRA2SwWtSzY+Cl+Q8ZRPGDbUxZ tU7unb7AFET0u04DlDBw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1tddUu-00000009kFn-0QAt; Thu, 30 Jan 2025 22:58:56 +0000 Received: from mail-pl1-x641.google.com ([2607:f8b0:4864:20::641]) by bombadil.infradead.org with esmtps (Exim 4.98 #2 (Red Hat Linux)) id 1tddUq-00000009kEe-3dPm for linux-riscv@lists.infradead.org; Thu, 30 Jan 2025 22:58:54 +0000 Received: by mail-pl1-x641.google.com with SMTP id d9443c01a7336-21ddb406f32so21394635ad.2 for ; Thu, 30 Jan 2025 14:58:52 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=rivosinc-com.20230601.gappssmtp.com; s=20230601; t=1738277931; x=1738882731; darn=lists.infradead.org; h=in-reply-to:content-transfer-encoding:content-disposition :mime-version:references:message-id:subject:cc:to:from:date:from:to :cc:subject:date:message-id:reply-to; bh=iqrirXyAiJow4eUPN0yWoilteak1+pXXR1BTytYKwjs=; b=jiQc4AmRVfLgtVX3D/U7L5Da/o7ohvdrBf/1XdK+xS+N+PaN0sMzLNOSGH54qZ4Y+Z GO5N7ZUm3YlY/ABlUgVnMOUVWVDVOA7NjbQiD3TzBmYyG+B/6XTUSBCx+5rhUbCD0W/S L5vgpOUKyEzDC1CnXBXdl6ecanHq2cnUsQ8sNAzKUMV526OH7R+jIlBoL4Yd+DaKZDu0 vhjSCUoypQQR24iyNCOgDaSY4RMxhEmSgRV8g7CAZVLw7yYES+Dl/QOR3XWsABnnZD6u Y2eqIi5OWTDrBMb4xYoXJcTKXYYupF8nV00TpxMQ65Xbo6QRmrugiq0GIFYLd0dV3lQO x2LA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1738277931; x=1738882731; h=in-reply-to:content-transfer-encoding:content-disposition :mime-version:references:message-id:subject:cc:to:from:date :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=iqrirXyAiJow4eUPN0yWoilteak1+pXXR1BTytYKwjs=; b=uK5QT55rdxolDdivkBLRPCfORsX/oGMugUjAwn3DoGmXr7HKTjxczV3O9XxmFmqg7f lxfz67/SqahE6k69y93wxg6d9VrKymSdqlR2igh8SDr0Trll9gmp+KwJh7eSKXGR3KB2 zn6Fxjl6mpgGiyu2N9LwIwD8ZvjxjM9C4ZAYSYmtLsIYSSunOzR71gBZeFBpmjwgf5u0 sVmPjcf0t8jsl+F7QKPlvXyCsajmQcxE4Dsbq8nHmW01Z4QAQJKxmJeeoMb0ED0kffpr VWQKgPmdP/PZ7/njmKTnOZJDy4+8HK7XBtUOKfXZDyAq7vl4zpQNwyrcM47WXf5oiKU5 nA5g== X-Forwarded-Encrypted: i=1; AJvYcCW+wZ1nkIVYbF3PFIBLyYqpcdufj6G3Bi2D4mX+9VblWG4zmcpT/1qhH2DxqPP9YrFSIfF5JsjOEwR4gQ==@lists.infradead.org X-Gm-Message-State: AOJu0YxPnAQpAjp+EX0iwvvnkBCzzAJzBgukodWBSLehnNV9zOh9fFC+ +F9u7Dlh83E8qEN8IkSfF4dxqfEd6uUKdt/E+ECD2gK0LvoxKNoUnPLhSZYeSHE= X-Gm-Gg: ASbGncsM69O+D2xiSpVGtmOFNpapIgmiW4XtnFap+zeKEODBOtJUrssf55RRyNAUUH2 oo2Z4B8lugVyIMGkR/i7NKZ6x8D36K1UudcXJUqn4wHI5no+AeFO49ouVnBEedREBM87VZTRgsJ DJIRWF/ZWJqaWZfUXuwDI9KtFfjqLzqVTk9R/dau+AifIRJgXYI0pAJoq/kXujjgvOSIa2DVGbu DY6PPl5yjhBfE5JMnr+Ys41DK2T5AAqlmo8jr9rmsF6u3ZAVP94RSfajH6NP1bTv0/+8mw6LSNQ 50dnm6Eevg== X-Google-Smtp-Source: AGHT+IHYG+kmnkJ+gnSZiRaOKEhXPOUeShSwAFPSZgtsxgjBVvqKWV5HeZeT27pl7Y4bSuSI8Ka2Tw== X-Received: by 2002:a17:903:18c:b0:216:49b1:fadc with SMTP id d9443c01a7336-21dd7deeef3mr132651725ad.42.1738277931641; Thu, 30 Jan 2025 14:58:51 -0800 (PST) Received: from ghost ([2001:428:6405:1e0:cd5c:b7b4:1f3d:62bb]) by smtp.gmail.com with ESMTPSA id d9443c01a7336-21de31f7885sm18881625ad.54.2025.01.30.14.58.50 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 30 Jan 2025 14:58:50 -0800 (PST) Date: Thu, 30 Jan 2025 14:58:49 -0800 From: Charlie Jenkins To: Conor Dooley Cc: Aleksandar Rikalo , linux-riscv@lists.infradead.org, Paul Walmsley , Palmer Dabbelt , Albert Ou , Andrew Jones , Christoph =?iso-8859-1?Q?M=FCllner?= , linux-kernel@vger.kernel.org, Djordje Todorovic Subject: Re: [PATCH v3] riscv: Fix the PAUSE Opcode for MIPS P8700. Message-ID: References: <20250129131703.733098-1-arikalo@gmail.com> <20250129-museum-slider-3bb634d124de@spud> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20250129-museum-slider-3bb634d124de@spud> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250130_145853_114253_2102681C X-CRM114-Status: GOOD ( 28.72 ) X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org T24gV2VkLCBKYW4gMjksIDIwMjUgYXQgMDQ6MTk6NThQTSArMDAwMCwgQ29ub3IgRG9vbGV5IHdy b3RlOgo+IE9uIFdlZCwgSmFuIDI5LCAyMDI1IGF0IDAyOjE3OjAzUE0gKzAxMDAsIEFsZWtzYW5k YXIgUmlrYWxvIHdyb3RlOgo+ID4gRnJvbTogRGpvcmRqZSBUb2Rvcm92aWMgPGRqb3JkamUudG9k b3JvdmljQGh0ZWNncm91cC5jb20+Cj4gPiAKPiA+IFRoZSByaXNjdiBNSVBTIFA4NzAwIHVzZXMg YSBkaWZmZXJlbnQgb3Bjb2RlIGZvciBQQVVTRS4KPiA+IEl0IGlzIGEg4oCYaGludOKAmSBlbmNv ZGluZyBvZiB0aGUgU0xMSSBpbnN0cnVjdGlvbiwgd2l0aCByZD0wLCByczE9MCBhbmQKPiA+IGlt bT01LiBJdCB3aWxsIGJlaGF2ZSBhcyBhIE5PUCBpbnN0cnVjdGlvbiBpZiBubyBhZGRpdGlvbmFs IGJlaGF2aW9yCj4gPiBiZXlvbmQgdGhhdCBvZiBTTExJIGlzIGltcGxlbWVudGVkLgo+IAo+IFlv dSBzYXkgcDg3MDAsIGJ1dCB0aGUgZXJyYXR1bSB3aWxsIGJlIGFwcGxpZWQgb24gYWxsIHN5c3Rl bXMgdGhhdCBhcmUKPiBpZGVudGlmaWVkIGFzIHVzaW5nIGEgbWlwcyBjcHUuIFdoeSdzIHRoYXQ/ Cj4gCj4gPiArdm9pZCBtaXBzX2VycmF0YV9wYXRjaF9mdW5jKHN0cnVjdCBhbHRfZW50cnkgKmJl Z2luLAo+ID4gKwkJCQkJICAgICBzdHJ1Y3QgYWx0X2VudHJ5ICplbmQsCj4gPiArCQkJCQkgICAg IHVuc2lnbmVkIGxvbmcgYXJjaGlkLAo+ID4gKwkJCQkJICAgICB1bnNpZ25lZCBsb25nIGltcGlk LAo+ID4gKwkJCQkJICAgICB1bnNpZ25lZCBpbnQgc3RhZ2UpCj4gPiArewo+ID4gKwlzdHJ1Y3Qg YWx0X2VudHJ5ICphbHQ7Cj4gPiArCj4gPiArCUJVSUxEX0JVR19PTihFUlJBVEFfTUlQU19OVU1C RVIgPj0gUklTQ1ZfVkVORE9SX0VYVF9BTFRFUk5BVElWRVNfQkFTRSk7Cj4gPiArCj4gPiArCWlm IChzdGFnZSA9PSBSSVNDVl9BTFRFUk5BVElWRVNfRUFSTFlfQk9PVCkKPiA+ICsJCXJldHVybjsK PiA+ICsKPiA+ICsJZm9yIChhbHQgPSBiZWdpbjsgYWx0IDwgZW5kOyBhbHQrKykgewo+ID4gKwkJ aWYgKGFsdC0+dmVuZG9yX2lkICE9IE1JUFNfVkVORE9SX0lEKQo+ID4gKwkJCWNvbnRpbnVlOwo+ ID4gKwo+ID4gKwkJaWYgKGFsdC0+cGF0Y2hfaWQgPj0gRVJSQVRBX01JUFNfTlVNQkVSKSB7Cj4g PiArCQkJV0FSTigxLCAiTUlQUyBlcnJhdGEgaWQ6JWQgbm90IGluIGtlcm5lbCBlcnJhdGEgbGlz dFxuIiwKPiA+ICsJCQkgICAgIGFsdC0+cGF0Y2hfaWQpOwo+ID4gKwkJCWNvbnRpbnVlOwo+ID4g KwkJfQo+ID4gKwo+ID4gKwkJbXV0ZXhfbG9jaygmdGV4dF9tdXRleCk7Cj4gPiArCQlwYXRjaF90 ZXh0X25vc3luYyhBTFRfT0xEX1BUUihhbHQpLCBBTFRfQUxUX1BUUihhbHQpLCBhbHQtPmFsdF9s ZW4pOwo+ID4gKwkJbXV0ZXhfdW5sb2NrKCZ0ZXh0X211dGV4KTsKPiA+ICsJfQo+ID4gK30KPiAK PiA+IGRpZmYgLS1naXQgYS90b29scy9hcmNoL3Jpc2N2L2luY2x1ZGUvYXNtL3Zkc28vcHJvY2Vz c29yLmggYi90b29scy9hcmNoL3Jpc2N2L2luY2x1ZGUvYXNtL3Zkc28vcHJvY2Vzc29yLmgKPiA+ IGluZGV4IDY2MmFjYTAzOTg0OC4uODgwZjI2YTI0ZjY5IDEwMDY0NAo+ID4gLS0tIGEvdG9vbHMv YXJjaC9yaXNjdi9pbmNsdWRlL2FzbS92ZHNvL3Byb2Nlc3Nvci5oCj4gPiArKysgYi90b29scy9h cmNoL3Jpc2N2L2luY2x1ZGUvYXNtL3Zkc28vcHJvY2Vzc29yLmgKPiA+IEBAIC0xNCw3ICsxNCwx MCBAQCBzdGF0aWMgaW5saW5lIHZvaWQgY3B1X3JlbGF4KHZvaWQpCj4gPiAgCV9fYXNtX18gX192 b2xhdGlsZV9fICgiZGl2ICUwLCAlMCwgemVybyIgOiAiPXIiIChkdW1teSkpOwo+ID4gICNlbmRp Zgo+ID4gIAo+ID4gLSNpZmRlZiBDT05GSUdfVE9PTENIQUlOX0hBU19aSUhJTlRQQVVTRQo+ID4g KyNpZmRlZiBDT05GSUdfRVJSQVRBX01JUFNfUDg3MDBfUEFVU0VfT1BDT0RFCj4gPiArICAgIC8q IE1JUFMgUDg3MDAgcGF1c2Ugb3Bjb2RlICovCj4gPiArICAgIF9fYXNtX18gX192b2xhdGlsZV9f ICgiLjRieXRlIDB4MDA1MDEwMTMiKTsKPiA+ICsjZWxpZiBDT05GSUdfVE9PTENIQUlOX0hBU19a SUhJTlRQQVVTRQo+ID4gIAkvKgo+ID4gIAkgKiBSZWR1Y2UgaW5zdHJ1Y3Rpb24gcmV0aXJlbWVu dC4KPiA+ICAJICogVGhpcyBhc3N1bWVzIHRoZSBQQyBjaGFuZ2VzLgo+IAo+IFdoYXQgYWJvdXQg d2hlbiB0aGUgZXJyYXR1bSBpcyBlbmFibGVkIGFuZCB0aGUgdG9vbGNoYWluIHN1cHBvcnRzCj4g WmloaW50cGF1c2U/CgpTbyB0aGUgb3RoZXIgd2F5IHRvIGRvIHRoaXMgaXMgaGF2aW5nIGFuIGh3 cHJvYmUgY2FsbCB0byBjaGVjayBpZiB0aGUKY3VycmVudGx5IHJ1bm5pbmcgcHJvY2Vzc29yIGlz IGVmZmVjdGVkIGJ5IHRoaXMuIEhvd2V2ZXIgSSB3YXMgY29uY2VybmVkCmFib3V0IHRoZSBwZXJm b3JtYW5jZSBwZW5hbHR5IG9mIGNhbGxpbmcgaHdwcm9iZSBoZXJlIGluIHRoZSBwcmV2aW91cwp2 ZXJzaW9uIHNvIEkgaGFkIHN1Z2dlc3RlZCB0byB1c2UgYSBmbGFnIGluc3RlYWQgc28gdGhlcmUg aXMgbm90IHRoZQpwZW5hbHR5IG9uIG90aGVyIGFyY2hpdGVjdHVyZXMuIFRoaXMgZG9lcyBtYWtl IGl0IGludmFsaWQgdG8gZW5hYmxlCnRoaXMgZXJyYXRhIGluIHRoZSBkZWZjb25maWcuIFRoaXMg aXMgYSBwcmVjZWRlbnQgZm9yIGhvdyB3ZSB3YW50IHRvCmhhbmRsZSBlcnJhdGEgaW4gdG9vbHMu Cgo+IFdoeSBkb24ndCB5b3UgdXNlIHRoZSBzYW1lIGltcGxlbWVudGF0aW9uIGFzIHRoZSAhdG9v bHMKPiBjb3B5IG9mIHRoZSBoZWFkZXI/IChJJ20gbm90IHN1cmUgd2h5IHRoZXkncmUgZGlmZmVy ZW50IGluIHRoZSBmaXJzdAo+IHBsYWNlKS4KCkl0IGlzIGRpZmZlcmVudCBiZWNhdXNlIHRoZSBo ZWFkZXJzIGluIHRvb2xzIGFyZSB1c2Vyc3BhY2Ugc28gaXQgZG9lc24ndAptYWtlIHNlbnNlIHRv IGhhdmUgYWx0ZXJuYXRpdmVzLgoKLSBDaGFybGllCgo+IF9fX19fX19fX19fX19fX19fX19fX19f X19fX19fX19fX19fX19fX19fX19fX19fCj4gbGludXgtcmlzY3YgbWFpbGluZyBsaXN0Cj4gbGlu dXgtcmlzY3ZAbGlzdHMuaW5mcmFkZWFkLm9yZwo+IGh0dHA6Ly9saXN0cy5pbmZyYWRlYWQub3Jn L21haWxtYW4vbGlzdGluZm8vbGludXgtcmlzY3YKCgpfX19fX19fX19fX19fX19fX19fX19fX19f X19fX19fX19fX19fX19fX19fX19fXwpsaW51eC1yaXNjdiBtYWlsaW5nIGxpc3QKbGludXgtcmlz Y3ZAbGlzdHMuaW5mcmFkZWFkLm9yZwpodHRwOi8vbGlzdHMuaW5mcmFkZWFkLm9yZy9tYWlsbWFu L2xpc3RpbmZvL2xpbnV4LXJpc2N2Cg== From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pl1-f195.google.com (mail-pl1-f195.google.com [209.85.214.195]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 77BBD12C499 for ; Thu, 30 Jan 2025 22:58:52 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.195 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1738277935; cv=none; b=I6xZAnccIygzFI6EFiCsHzZe80dwm2KL+UtWcu3J0947Urq8l9VB+6Z2BcNYexnPJ+9ltPQqUdqw2mSzKSfufHE16cdpCYaLIsUBvOMkgn2ESREAnF16VFztlH/DPaZDNMXn6IqyrLNVh7MK5+59tVxbLmZ6wQnHD4tGGR/Mjd0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1738277935; c=relaxed/simple; bh=pAn1iIMRIIBCqSolqYletqe8y+x3siOw0uL2FvEbOF0=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=pImF7ybkNKBLDzkgwrKFsgPkNad3GUBSd7wOAs4oh+Y/sM5t1yG9FmilJlg+2Z1sJDyXmZ92XjqQpSKi22R0brwtCRzVDISSWOnwYgy0cFV2bjeF4ZqkdPqkpEy5aGNGodAGdnr+FPwuY5nhjoT3xUaAjt/SXFjfRYBbLVMMan8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=rivosinc.com; spf=pass smtp.mailfrom=rivosinc.com; dkim=pass (2048-bit key) header.d=rivosinc-com.20230601.gappssmtp.com header.i=@rivosinc-com.20230601.gappssmtp.com header.b=aEssRJr4; arc=none smtp.client-ip=209.85.214.195 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=rivosinc.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=rivosinc.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=rivosinc-com.20230601.gappssmtp.com header.i=@rivosinc-com.20230601.gappssmtp.com header.b="aEssRJr4" Received: by mail-pl1-f195.google.com with SMTP id d9443c01a7336-2166651f752so14024925ad.3 for ; Thu, 30 Jan 2025 14:58:52 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=rivosinc-com.20230601.gappssmtp.com; s=20230601; t=1738277931; x=1738882731; darn=vger.kernel.org; h=in-reply-to:content-transfer-encoding:content-disposition :mime-version:references:message-id:subject:cc:to:from:date:from:to :cc:subject:date:message-id:reply-to; bh=iqrirXyAiJow4eUPN0yWoilteak1+pXXR1BTytYKwjs=; b=aEssRJr4oujzoLm/qvgL7KfCT/6j/0JIa8E/ILuee4Ww7WNs9ez6k/QtQ65uE51cJ3 pHoS1ZXb/RPU9DPpxWAycGxXIk9HunTLbvMvcXDKYtb7Yd9wCbpdyqUfBohhoyvhNjB+ RKWr6TWxsoLCJmzxcKaRSB3Dg9GfFrq7WXdbW8odVGIbp9q6CZC6ZW+MFVqsOv4H0Edl sI8sQxnDr/Uxz+nqxOnsXNef68KdFYdl0Zo96bvkZWfRi7jbTChE/pcQSdhP4p7zqD6/ NcRazf/DoVrcA2vXSvu+Od29CH5913bv2j0yF+kd2q7PPzhwWVZLI7zqcakp7klo8kDx 5aEg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1738277931; x=1738882731; h=in-reply-to:content-transfer-encoding:content-disposition :mime-version:references:message-id:subject:cc:to:from:date :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=iqrirXyAiJow4eUPN0yWoilteak1+pXXR1BTytYKwjs=; b=J5jUr6z/AG++ZyY2CGiGIVVsipL34Zwqi8Xmbn9smZpE4wSAXfR/xQsBPe2K7GEtyC qmBCAAOWde+yKpEa7RexasPcMgPsWb2yelsbyLUUbFmrnmNy8eIzoFNlIuoqP4V/LcR3 1xJMbrVu5VmYppCHU0zADr+fVToTnpY7juFB9QN0KZ9PNbACqMCzxkegeBke1rE1Tdk4 FjWyEP32IVC/JE931EcyEd6lLKxQW0YP8O6UdD0Sd+izCFO6h0CQlIw6jx0qdWf9MMLK fqFgz1mU+yliyyvFZJCLJCQMkV/7bn6V/uAxSNQRvN/zz9/GUXJtJXxiRm1hlAAq018U Pnog== X-Forwarded-Encrypted: i=1; AJvYcCWYf/d8ai6nfnsR6t14VpMZrFziPuyY3avj7v8hDcScEky6PBJBTpsoTOHM+3QRtzrg6em/tCIIn3T5s1E=@vger.kernel.org X-Gm-Message-State: AOJu0YxbVPKAE0A2nSH9Au7p2Q8Ei17pTM0HoOtr5Moc7md2ECZ5klM6 lksU4b38oeYY6Cv9suAkCRp0xN9JqZj5S6vy4JBcxvEAoT71Wb6aeMTWUdour8k= X-Gm-Gg: ASbGncuxu7xoNriNRihe75dnll8zD4fO132wxVcubXLt55rjJuNkRiex3NYEGj7aQQJ OvRulKkH/d5kEv2dOLJ3zST7UnwLQT+qJCRahxI5nowU49EZ6XCUoFK+4YjiDC8jEeNSzlMiD9t YTYslcb+ptnSXa4/0S+l9E0VSX1rFj6VjFlFn9L/6sVZOy8QzShvSnxl2beIEpEV20kZYVwH2Aj BW2IPMBYQJfs/Gke2ojSyD3wqlLG3Pq1OAsq0/H82x055ZMo/qZbnhugWPBI2QAKgb7A4xK9nKy 4sXzOEAO5Q== X-Google-Smtp-Source: AGHT+IHYG+kmnkJ+gnSZiRaOKEhXPOUeShSwAFPSZgtsxgjBVvqKWV5HeZeT27pl7Y4bSuSI8Ka2Tw== X-Received: by 2002:a17:903:18c:b0:216:49b1:fadc with SMTP id d9443c01a7336-21dd7deeef3mr132651725ad.42.1738277931641; Thu, 30 Jan 2025 14:58:51 -0800 (PST) Received: from ghost ([2001:428:6405:1e0:cd5c:b7b4:1f3d:62bb]) by smtp.gmail.com with ESMTPSA id d9443c01a7336-21de31f7885sm18881625ad.54.2025.01.30.14.58.50 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 30 Jan 2025 14:58:50 -0800 (PST) Date: Thu, 30 Jan 2025 14:58:49 -0800 From: Charlie Jenkins To: Conor Dooley Cc: Aleksandar Rikalo , linux-riscv@lists.infradead.org, Paul Walmsley , Palmer Dabbelt , Albert Ou , Andrew Jones , Christoph =?iso-8859-1?Q?M=FCllner?= , linux-kernel@vger.kernel.org, Djordje Todorovic Subject: Re: [PATCH v3] riscv: Fix the PAUSE Opcode for MIPS P8700. Message-ID: References: <20250129131703.733098-1-arikalo@gmail.com> <20250129-museum-slider-3bb634d124de@spud> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20250129-museum-slider-3bb634d124de@spud> On Wed, Jan 29, 2025 at 04:19:58PM +0000, Conor Dooley wrote: > On Wed, Jan 29, 2025 at 02:17:03PM +0100, Aleksandar Rikalo wrote: > > From: Djordje Todorovic > > > > The riscv MIPS P8700 uses a different opcode for PAUSE. > > It is a ‘hint’ encoding of the SLLI instruction, with rd=0, rs1=0 and > > imm=5. It will behave as a NOP instruction if no additional behavior > > beyond that of SLLI is implemented. > > You say p8700, but the erratum will be applied on all systems that are > identified as using a mips cpu. Why's that? > > > +void mips_errata_patch_func(struct alt_entry *begin, > > + struct alt_entry *end, > > + unsigned long archid, > > + unsigned long impid, > > + unsigned int stage) > > +{ > > + struct alt_entry *alt; > > + > > + BUILD_BUG_ON(ERRATA_MIPS_NUMBER >= RISCV_VENDOR_EXT_ALTERNATIVES_BASE); > > + > > + if (stage == RISCV_ALTERNATIVES_EARLY_BOOT) > > + return; > > + > > + for (alt = begin; alt < end; alt++) { > > + if (alt->vendor_id != MIPS_VENDOR_ID) > > + continue; > > + > > + if (alt->patch_id >= ERRATA_MIPS_NUMBER) { > > + WARN(1, "MIPS errata id:%d not in kernel errata list\n", > > + alt->patch_id); > > + continue; > > + } > > + > > + mutex_lock(&text_mutex); > > + patch_text_nosync(ALT_OLD_PTR(alt), ALT_ALT_PTR(alt), alt->alt_len); > > + mutex_unlock(&text_mutex); > > + } > > +} > > > diff --git a/tools/arch/riscv/include/asm/vdso/processor.h b/tools/arch/riscv/include/asm/vdso/processor.h > > index 662aca039848..880f26a24f69 100644 > > --- a/tools/arch/riscv/include/asm/vdso/processor.h > > +++ b/tools/arch/riscv/include/asm/vdso/processor.h > > @@ -14,7 +14,10 @@ static inline void cpu_relax(void) > > __asm__ __volatile__ ("div %0, %0, zero" : "=r" (dummy)); > > #endif > > > > -#ifdef CONFIG_TOOLCHAIN_HAS_ZIHINTPAUSE > > +#ifdef CONFIG_ERRATA_MIPS_P8700_PAUSE_OPCODE > > + /* MIPS P8700 pause opcode */ > > + __asm__ __volatile__ (".4byte 0x00501013"); > > +#elif CONFIG_TOOLCHAIN_HAS_ZIHINTPAUSE > > /* > > * Reduce instruction retirement. > > * This assumes the PC changes. > > What about when the erratum is enabled and the toolchain supports > Zihintpause? So the other way to do this is having an hwprobe call to check if the currently running processor is effected by this. However I was concerned about the performance penalty of calling hwprobe here in the previous version so I had suggested to use a flag instead so there is not the penalty on other architectures. This does make it invalid to enable this errata in the defconfig. This is a precedent for how we want to handle errata in tools. > Why don't you use the same implementation as the !tools > copy of the header? (I'm not sure why they're different in the first > place). It is different because the headers in tools are userspace so it doesn't make sense to have alternatives. - Charlie > _______________________________________________ > linux-riscv mailing list > linux-riscv@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-riscv