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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 74D64C433F5 for ; Thu, 24 Feb 2022 12:39:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234450AbiBXMj4 (ORCPT ); Thu, 24 Feb 2022 07:39:56 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43858 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231701AbiBXMjz (ORCPT ); Thu, 24 Feb 2022 07:39:55 -0500 Received: from gandalf.ozlabs.org (gandalf.ozlabs.org [150.107.74.76]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AE9322804DB; Thu, 24 Feb 2022 04:39:24 -0800 (PST) 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 4K4CCD07MVz4xdl; Thu, 24 Feb 2022 23:39:19 +1100 (AEDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ellerman.id.au; s=201909; t=1645706360; bh=8EGa3eVWgTEde2gYL1wkBviDfIH/E8ovFgLPoK3d+ZA=; h=From:To:Cc:Subject:In-Reply-To:References:Date:From; b=Z7jT6vn3oi7dj7yRyZFUSJ33xHIOjzEkBxgWvQED7rbUeElVkn5TZSjvGL1xgTjTU 03oa7LTrNlJnR5xoPnkT2cPYIWZpWl+0VkAnpTkpKUzASb9zNA+jtrRcjMyLU+9KZh QoeXdMDJ//OWfvhkt8lZwRbVAbA6nh5BeatTk1bKLM1SQdJNQzkH+sgatR9dJx1wOu iwe7fQ9bU3sa9rcDzhO6w27FgQDYgyKwNMg6TEh0pL9qBhm1hNdJ6EEjzpzFBMlosz 8ybLHAXvgTLwGIQZ05zC+27evp33N91vl97MnWqYxfKWVV+3agjufpv1hUNGqdNlTL Xx1LzKpeo8xoQ== From: Michael Ellerman To: Anders Roxell Cc: linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, Anders Roxell , stable@vger.kernel.org, Arnd Bergmann Subject: Re: [PATCH 2/3] powerpc: fix build errors In-Reply-To: <20220223135820.2252470-2-anders.roxell@linaro.org> References: <20220223135820.2252470-1-anders.roxell@linaro.org> <20220223135820.2252470-2-anders.roxell@linaro.org> Date: Thu, 24 Feb 2022 23:39:16 +1100 Message-ID: <871qzsphfv.fsf@mpe.ellerman.id.au> MIME-Version: 1.0 Content-Type: text/plain Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Anders, Thanks for these, just a few comments below ... Anders Roxell writes: > Building tinyconfig with gcc (Debian 11.2.0-16) and assembler (Debian > 2.37.90.20220207) the following build error shows up: > > {standard input}: Assembler messages: > {standard input}:1190: Error: unrecognized opcode: `stbcix' > {standard input}:1433: Error: unrecognized opcode: `lwzcix' > {standard input}:1453: Error: unrecognized opcode: `stbcix' > {standard input}:1460: Error: unrecognized opcode: `stwcix' > {standard input}:1596: Error: unrecognized opcode: `stbcix' > ... > > Rework to add assembler directives [1] around the instruction. Going > through the them one by one shows that the changes should be safe. Like > __get_user_atomic_128_aligned() is only called in p9_hmi_special_emu(), > which according to the name is specific to power9. And __raw_rm_read*() > are only called in things that are powernv or book3s_hv specific. > > [1] https://sourceware.org/binutils/docs/as/PowerPC_002dPseudo.html#PowerPC_002dPseudo > > Cc: > Co-developed-by: Arnd Bergmann > Signed-off-by: Arnd Bergmann > Signed-off-by: Anders Roxell > --- > arch/powerpc/include/asm/io.h | 46 +++++++++++++++++++++++----- > arch/powerpc/include/asm/uaccess.h | 3 ++ > arch/powerpc/platforms/powernv/rng.c | 6 +++- > 3 files changed, 46 insertions(+), 9 deletions(-) > > diff --git a/arch/powerpc/include/asm/io.h b/arch/powerpc/include/asm/io.h > index beba4979bff9..5ff6dec489f8 100644 > --- a/arch/powerpc/include/asm/io.h > +++ b/arch/powerpc/include/asm/io.h > @@ -359,25 +359,37 @@ static inline void __raw_writeq_be(unsigned long v, volatile void __iomem *addr) > */ > static inline void __raw_rm_writeb(u8 val, volatile void __iomem *paddr) > { > - __asm__ __volatile__("stbcix %0,0,%1" > + __asm__ __volatile__(".machine \"push\"\n" > + ".machine \"power6\"\n" > + "stbcix %0,0,%1\n" > + ".machine \"pop\"\n" > : : "r" (val), "r" (paddr) : "memory"); As Segher said it'd be cleaner without the embedded quotes. > @@ -441,7 +465,10 @@ static inline unsigned int name(unsigned int port) \ > unsigned int x; \ > __asm__ __volatile__( \ > "sync\n" \ > + ".machine \"push\"\n" \ > + ".machine \"power6\"\n" \ > "0:" op " %0,0,%1\n" \ > + ".machine \"pop\"\n" \ > "1: twi 0,%0,0\n" \ > "2: isync\n" \ > "3: nop\n" \ > @@ -465,7 +492,10 @@ static inline void name(unsigned int val, unsigned int port) \ > { \ > __asm__ __volatile__( \ > "sync\n" \ > + ".machine \"push\"\n" \ > + ".machine \"power6\"\n" \ > "0:" op " %0,0,%1\n" \ > + ".machine \"pop\"\n" \ > "1: sync\n" \ > "2:\n" \ > EX_TABLE(0b, 2b) \ It's not visible from the diff, but the above two are __do_in_asm and __do_out_asm and are inside an ifdef CONFIG_PPC32. AFAICS they're only used for: __do_in_asm(_rec_inb, "lbzx") __do_in_asm(_rec_inw, "lhbrx") __do_in_asm(_rec_inl, "lwbrx") __do_out_asm(_rec_outb, "stbx") __do_out_asm(_rec_outw, "sthbrx") __do_out_asm(_rec_outl, "stwbrx") Which are all old instructions, so I don't think we need the machine power6 for those two macros? > diff --git a/arch/powerpc/platforms/powernv/rng.c b/arch/powerpc/platforms/powernv/rng.c > index b4386714494a..5bf30ef6d928 100644 > --- a/arch/powerpc/platforms/powernv/rng.c > +++ b/arch/powerpc/platforms/powernv/rng.c > @@ -43,7 +43,11 @@ static unsigned long rng_whiten(struct powernv_rng *rng, unsigned long val) > unsigned long parity; > > /* Calculate the parity of the value */ > - asm ("popcntd %0,%1" : "=r" (parity) : "r" (val)); > + asm (".machine \"push\"\n" > + ".machine \"power7\"\n" > + "popcntd %0,%1\n" > + ".machine \"pop\"\n" > + : "=r" (parity) : "r" (val)); This was actually present in an older CPU, but it doesn't really matter, this is fine. cheers