From patchwork Sun Sep 1 15:46:18 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Fredrik Noring X-Patchwork-Id: 11125327 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 832541395 for ; Sun, 1 Sep 2019 15:46:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6B83A233A2 for ; Sun, 1 Sep 2019 15:46:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728934AbfIAPqW (ORCPT ); Sun, 1 Sep 2019 11:46:22 -0400 Received: from pio-pvt-msa1.bahnhof.se ([79.136.2.40]:56560 "EHLO pio-pvt-msa1.bahnhof.se" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728621AbfIAPqV (ORCPT ); Sun, 1 Sep 2019 11:46:21 -0400 Received: from localhost (localhost [127.0.0.1]) by pio-pvt-msa1.bahnhof.se (Postfix) with ESMTP id 793DB40F37; Sun, 1 Sep 2019 17:46:19 +0200 (CEST) X-Virus-Scanned: Debian amavisd-new at bahnhof.se X-Spam-Flag: NO X-Spam-Score: -1.899 X-Spam-Level: X-Spam-Status: No, score=-1.899 tagged_above=-999 required=6.31 tests=[BAYES_00=-1.9, URIBL_BLOCKED=0.001] autolearn=ham autolearn_force=no Received: from pio-pvt-msa1.bahnhof.se ([127.0.0.1]) by localhost (pio-pvt-msa1.bahnhof.se [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id LAhCrnRSKkBy; Sun, 1 Sep 2019 17:46:18 +0200 (CEST) Received: from localhost (h-41-252.A163.priv.bahnhof.se [46.59.41.252]) (Authenticated sender: mb547485) by pio-pvt-msa1.bahnhof.se (Postfix) with ESMTPA id 8775E40C35; Sun, 1 Sep 2019 17:46:18 +0200 (CEST) Date: Sun, 1 Sep 2019 17:46:18 +0200 From: Fredrik Noring To: Paul Burton , linux-mips@vger.kernel.org Cc: "Maciej W. Rozycki" , =?utf-8?q?J=C3=BCrgen?= Urban Subject: [PATCH 022/120] MIPS: R5900: Support 64-bit inq() and outq() macros in 32-bit kernels Message-ID: <7ea8b1211bceb8193154b51ad4241e7c0b86547d.1567326213.git.noring@nocrew.org> References: MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-mips-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-mips@vger.kernel.org PlayStation 2 hardware such as the Graphics Synthesizer requires 64-bit register reads and writes[1], also in 32-bit kernels. Interrupts must be disabled when manipulating 64-bit registers unless the kernel saves and restores 64-bit registers in the interrupt and context switch handlers. References: [1] "EE User's Manual", version 6.0, Sony Computer Entertainment Inc., p. 26: GS privileged registers must be accessed using LD/SD instructions. Signed-off-by: Fredrik Noring --- arch/mips/include/asm/io.h | 54 +++++++++++++++++++++++++++++++++----- 1 file changed, 47 insertions(+), 7 deletions(-) diff --git a/arch/mips/include/asm/io.h b/arch/mips/include/asm/io.h index 97a280640daf..f7115472f530 100644 --- a/arch/mips/include/asm/io.h +++ b/arch/mips/include/asm/io.h @@ -420,10 +420,32 @@ static inline void pfx##out##bwlq##p(type val, unsigned long port) \ \ __val = pfx##ioswab##bwlq(__addr, val); \ \ - /* Really, we want this to be atomic */ \ - BUILD_BUG_ON(sizeof(type) > sizeof(unsigned long)); \ + if (sizeof(type) != sizeof(u64) || sizeof(u64) == sizeof(long)) { \ + *__addr = __val; \ + } else if (cpu_has_64bits) { \ + unsigned long __flags; \ + type __tmp; \ \ - *__addr = __val; \ + /* Manipulating 64-bit registers in a 32-bit kernel */ \ + /* requires disabling interrupts, since only 32-bit */ \ + /* registers are saved/restored by interrupts. */ \ + local_irq_save(__flags); \ + __asm__ __volatile__( \ + ".set push" "\t\t# __writeq""\n\t" \ + ".set mips3" "\n\t" \ + "dsll32 %L0, %L0, 0" "\n\t" \ + "dsrl32 %L0, %L0, 0" "\n\t" \ + "dsll32 %M0, %M0, 0" "\n\t" \ + "or %L0, %L0, %M0" "\n\t" \ + "sd %L0, %2" "\n\t" \ + "sll %L0, %L0, 0" "\n\t" \ + "sll %M0, %M0, 0" "\n\t" \ + ".set pop" "\n" \ + : "=r" (__tmp) \ + : "0" (__val), "m" (*__addr)); \ + local_irq_restore(__flags); \ + } else \ + BUG(); \ } \ \ static inline type pfx##in##bwlq##p(unsigned long port) \ @@ -433,12 +455,30 @@ static inline type pfx##in##bwlq##p(unsigned long port) \ \ __addr = (void *)__swizzle_addr_##bwlq(mips_io_port_base + port); \ \ - BUILD_BUG_ON(sizeof(type) > sizeof(unsigned long)); \ - \ if (barrier) \ iobarrier_rw(); \ \ - __val = *__addr; \ + if (sizeof(type) != sizeof(u64) || sizeof(u64) == sizeof(long)) { \ + __val = *__addr; \ + } else if (cpu_has_64bits) { \ + unsigned long __flags; \ + \ + /* Manipulating 64-bit registers in a 32-bit kernel */ \ + /* requires disabling interrupts, since only 32-bit */ \ + /* registers are saved/restored by interrupts. */ \ + local_irq_save(__flags); \ + __asm__ __volatile__( \ + ".set push" "\t\t# __outq" "\n\t" \ + ".set mips3" "\n\t" \ + "ld %L0, %1" "\n\t" \ + "dsra32 %M0, %L0, 0" "\n\t" \ + "sll %L0, %L0, 0" "\n\t" \ + ".set pop" "\n" \ + : "=r" (__val) \ + : "m" (*__addr)); \ + local_irq_restore(__flags); \ + } else \ + BUG(); \ \ /* prevent prefetching of coherent DMA data prematurely */ \ if (!relax) \ @@ -478,7 +518,7 @@ __BUILD_MEMORY_PFX(__mem_, q, u64, 0) BUILDIO_IOPORT(b, u8) BUILDIO_IOPORT(w, u16) BUILDIO_IOPORT(l, u32) -#ifdef CONFIG_64BIT +#if defined(CONFIG_64BIT) || defined(CONFIG_CPU_R5900) BUILDIO_IOPORT(q, u64) #endif