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 X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5314EC432C3 for ; Thu, 14 Nov 2019 09:24:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2039D206C0 for ; Thu, 14 Nov 2019 09:24:50 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=ellerman.id.au header.i=@ellerman.id.au header.b="dT+kTu6+" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726378AbfKNJYs (ORCPT ); Thu, 14 Nov 2019 04:24:48 -0500 Received: from ozlabs.org ([203.11.71.1]:58785 "EHLO ozlabs.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726010AbfKNJYs (ORCPT ); Thu, 14 Nov 2019 04:24:48 -0500 Received: from authenticated.ozlabs.org (localhost [127.0.0.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-256) server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by mail.ozlabs.org (Postfix) with ESMTPSA id 47DGK86mv8z9s7T; Thu, 14 Nov 2019 20:24:44 +1100 (AEDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ellerman.id.au; s=201909; t=1573723485; bh=Dq7NW4klV4GxHT1oNqdnPAGrN68C+hoVfrP2Pb0IXcs=; h=From:To:Cc:Subject:In-Reply-To:References:Date:From; b=dT+kTu6+/7TIMNxlEx1NDQPpULL2+1zfqJ+NHNsr7R31lqunFGgaL3emKJ6s8u5CL QYjFXnpzEg+8t5UF1g1VJPPMczqTpGmfb6CI8Y0FmeXPjS6A4GiDKRQCheG08f8ppb ihU47C4OvatTXUjjTtw95ACCJjoaTkDhHDi5lXLkUbj490cPMgrNGH9+Gx5bYBSjkb +6mi2t3QOty39wiT9BugiOXMKmuBjwaa56STR2a76ZTnXicXFLLSq/uyvU/SmtX+aq Wqp2EUOGhtXw0Zhckr05x1oovqMnrZgtaV5JJw2PS/Ffkg1Q+mRt9UMDU207AP9lbb OBdQsF4GuVMKA== From: Michael Ellerman To: Christophe Leroy , Benjamin Herrenschmidt , Paul Mackerras , ravi.bangoria@linux.ibm.com Cc: linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org Subject: Re: [PATCH 2/2] powerpc/hw_breakpoints: Rewrite 8xx breakpoints to allow any address range size. In-Reply-To: <1ed0de54ce6021fa0fdf50e938365546a4f5e316.1566925030.git.christophe.leroy@c-s.fr> References: <1ed0de54ce6021fa0fdf50e938365546a4f5e316.1566925030.git.christophe.leroy@c-s.fr> Date: Thu, 14 Nov 2019 20:24:41 +1100 Message-ID: <87zhgyzu7a.fsf@mpe.ellerman.id.au> MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Christophe Leroy writes: > Unlike standard powerpc, Powerpc 8xx doesn't have SPRN_DABR, but > it has a breakpoint support based on a set of comparators which > allow more flexibility. > > Commit 4ad8622dc548 ("powerpc/8xx: Implement hw_breakpoint") > implemented breakpoints by emulating the DABR behaviour. It did > this by setting one comparator the match 4 bytes at breakpoint address > and the other comparator to match 4 bytes at breakpoint address + 4. > > Rewrite 8xx hw_breakpoint to make breakpoints match all addresses > defined by the breakpoint address and length by making full use of > comparators. > > Now, comparator E is set to match any address greater than breakpoint > address minus one. Comparator F is set to match any address lower than > breakpoint address plus breakpoint length. > > When the breakpoint range starts at address 0, the breakpoint is set > to match comparator F only. When the breakpoint range end at address > 0xffffffff, the breakpoint is set to match comparator E only. > Otherwise the breakpoint is set to match comparator E and F. > > At the same time, use registers bit names instead of hardcode values. > > Signed-off-by: Christophe Leroy > Cc: Ravi Bangoria > --- > arch/powerpc/include/asm/reg_8xx.h | 14 ++++++++++ > arch/powerpc/kernel/hw_breakpoint.c | 3 ++ > arch/powerpc/kernel/process.c | 55 ++++++++++++++++++++++--------------- > 3 files changed, 50 insertions(+), 22 deletions(-) I thought Ravi was going to pick this up in his series, but seems not. So now this no longer applies since I merged that series. Can one of you rebase and resend please? cheers > diff --git a/arch/powerpc/include/asm/reg_8xx.h b/arch/powerpc/include/asm/reg_8xx.h > index abc663c0f1db..98e97c22df8b 100644 > --- a/arch/powerpc/include/asm/reg_8xx.h > +++ b/arch/powerpc/include/asm/reg_8xx.h > @@ -37,7 +37,21 @@ > #define SPRN_CMPE 152 > #define SPRN_CMPF 153 > #define SPRN_LCTRL1 156 > +#define LCTRL1_CTE_GT 0xc0000000 > +#define LCTRL1_CTF_LT 0x14000000 > +#define LCTRL1_CRWE_RW 0x00000000 > +#define LCTRL1_CRWE_RO 0x00040000 > +#define LCTRL1_CRWE_WO 0x000c0000 > +#define LCTRL1_CRWF_RW 0x00000000 > +#define LCTRL1_CRWF_RO 0x00010000 > +#define LCTRL1_CRWF_WO 0x00030000 > #define SPRN_LCTRL2 157 > +#define LCTRL2_LW0EN 0x80000000 > +#define LCTRL2_LW0LA_E 0x00000000 > +#define LCTRL2_LW0LA_F 0x04000000 > +#define LCTRL2_LW0LA_EandF 0x08000000 > +#define LCTRL2_LW0LADC 0x02000000 > +#define LCTRL2_SLW0EN 0x00000002 > #ifdef CONFIG_PPC_8xx > #define SPRN_ICTRL 158 > #endif > diff --git a/arch/powerpc/kernel/hw_breakpoint.c b/arch/powerpc/kernel/hw_breakpoint.c > index 28ad3171bb82..d8bd4dbef561 100644 > --- a/arch/powerpc/kernel/hw_breakpoint.c > +++ b/arch/powerpc/kernel/hw_breakpoint.c > @@ -163,6 +163,9 @@ int hw_breakpoint_arch_parse(struct perf_event *bp, > */ > if (!ppc_breakpoint_available()) > return -ENODEV; > + /* 8xx can setup a range without limitation */ > + if (IS_ENABLED(CONFIG_PPC_8xx)) > + return 0; > length_max = 8; /* DABR */ > if (dawr_enabled()) { > length_max = 512 ; /* 64 doublewords */ > diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c > index 8fc4de0d22b4..79e4f072a746 100644 > --- a/arch/powerpc/kernel/process.c > +++ b/arch/powerpc/kernel/process.c > @@ -751,28 +751,6 @@ static inline int __set_dabr(unsigned long dabr, unsigned long dabrx) > mtspr(SPRN_DABRX, dabrx); > return 0; > } > -#elif defined(CONFIG_PPC_8xx) > -static inline int __set_dabr(unsigned long dabr, unsigned long dabrx) > -{ > - unsigned long addr = dabr & ~HW_BRK_TYPE_DABR; > - unsigned long lctrl1 = 0x90000000; /* compare type: equal on E & F */ > - unsigned long lctrl2 = 0x8e000002; /* watchpoint 1 on cmp E | F */ > - > - if ((dabr & HW_BRK_TYPE_RDWR) == HW_BRK_TYPE_READ) > - lctrl1 |= 0xa0000; > - else if ((dabr & HW_BRK_TYPE_RDWR) == HW_BRK_TYPE_WRITE) > - lctrl1 |= 0xf0000; > - else if ((dabr & HW_BRK_TYPE_RDWR) == 0) > - lctrl2 = 0; > - > - mtspr(SPRN_LCTRL2, 0); > - mtspr(SPRN_CMPE, addr); > - mtspr(SPRN_CMPF, addr + 4); > - mtspr(SPRN_LCTRL1, lctrl1); > - mtspr(SPRN_LCTRL2, lctrl2); > - > - return 0; > -} > #else > static inline int __set_dabr(unsigned long dabr, unsigned long dabrx) > { > @@ -793,6 +771,37 @@ static inline int set_dabr(struct arch_hw_breakpoint *brk) > return __set_dabr(dabr, dabrx); > } > > +static inline int set_breakpoint_8xx(struct arch_hw_breakpoint *brk) > +{ > + unsigned long lctrl1 = LCTRL1_CTE_GT | LCTRL1_CTF_LT | LCTRL1_CRWE_RW | > + LCTRL1_CRWF_RW; > + unsigned long lctrl2 = LCTRL2_LW0EN | LCTRL2_LW0LADC | LCTRL2_SLW0EN; > + > + if (brk->address == 0) > + lctrl2 |= LCTRL2_LW0LA_F; > + else if (brk->address + brk->len == 0) > + lctrl2 |= LCTRL2_LW0LA_E; > + else > + lctrl2 |= LCTRL2_LW0LA_EandF; > + > + mtspr(SPRN_LCTRL2, 0); > + > + if ((brk->type & HW_BRK_TYPE_RDWR) == 0) > + return 0; > + > + if ((brk->type & HW_BRK_TYPE_RDWR) == HW_BRK_TYPE_READ) > + lctrl1 |= LCTRL1_CRWE_RO | LCTRL1_CRWF_RO; > + if ((brk->type & HW_BRK_TYPE_RDWR) == HW_BRK_TYPE_WRITE) > + lctrl1 |= LCTRL1_CRWE_WO | LCTRL1_CRWF_WO; > + > + mtspr(SPRN_CMPE, brk->address - 1); > + mtspr(SPRN_CMPF, brk->address + brk->len); > + mtspr(SPRN_LCTRL1, lctrl1); > + mtspr(SPRN_LCTRL2, lctrl2); > + > + return 0; > +} > + > void __set_breakpoint(struct arch_hw_breakpoint *brk) > { > memcpy(this_cpu_ptr(¤t_brk), brk, sizeof(*brk)); > @@ -800,6 +809,8 @@ void __set_breakpoint(struct arch_hw_breakpoint *brk) > if (dawr_enabled()) > // Power8 or later > set_dawr(brk); > + else if (IS_ENABLED(CONFIG_PPC_8xx)) > + set_breakpoint_8xx(brk); > else if (!cpu_has_feature(CPU_FTR_ARCH_207S)) > // Power7 or earlier > set_dabr(brk); > -- > 2.13.3