From patchwork Sun Sep 1 15:41:41 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Fredrik Noring X-Patchwork-Id: 11125393 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 84E091395 for ; Sun, 1 Sep 2019 15:51:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 63036233A2 for ; Sun, 1 Sep 2019 15:51:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728753AbfIAPvL (ORCPT ); Sun, 1 Sep 2019 11:51:11 -0400 Received: from pio-pvt-msa3.bahnhof.se ([79.136.2.42]:41792 "EHLO pio-pvt-msa3.bahnhof.se" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726260AbfIAPvK (ORCPT ); Sun, 1 Sep 2019 11:51:10 -0400 Received: from localhost (localhost [127.0.0.1]) by pio-pvt-msa3.bahnhof.se (Postfix) with ESMTP id 1B13F3F6B8 for ; Sun, 1 Sep 2019 17:41:42 +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-msa3.bahnhof.se ([127.0.0.1]) by localhost (pio-pvt-msa3.bahnhof.se [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id BysIxn_d_7g7 for ; Sun, 1 Sep 2019 17:41:41 +0200 (CEST) Received: from localhost (h-41-252.A163.priv.bahnhof.se [46.59.41.252]) (Authenticated sender: mb547485) by pio-pvt-msa3.bahnhof.se (Postfix) with ESMTPA id 7C8AB3F69D for ; Sun, 1 Sep 2019 17:41:41 +0200 (CEST) Date: Sun, 1 Sep 2019 17:41:41 +0200 From: Fredrik Noring To: linux-mips@vger.kernel.org Subject: [PATCH 016/120] MIPS: R5900: The ERET instruction has issues with delay slot and CACHE Message-ID: <3a2945e9ac2b70c6f6b14100bf8c805d3ef51ce0.1567326213.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 Signed-off-by: Fredrik Noring --- The Linux 2.6 port to the PlayStation 2 has this remark. I don't know where it comes from. --- arch/mips/mm/tlbex.c | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) diff --git a/arch/mips/mm/tlbex.c b/arch/mips/mm/tlbex.c index 1bd134b6f033..9d5864b20e9f 100644 --- a/arch/mips/mm/tlbex.c +++ b/arch/mips/mm/tlbex.c @@ -1383,6 +1383,16 @@ static void build_r4000_tlb_refill_handler(void) uasm_l_leave(&l, p); uasm_i_eret(&p); /* return from trap */ } + +#ifdef CONFIG_CPU_R5900 + /* There should be nothing which can be interpreted as cache instruction. */ + uasm_i_nop(&p); + uasm_i_nop(&p); + uasm_i_nop(&p); + uasm_i_nop(&p); + uasm_i_nop(&p); +#endif + #ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT uasm_l_tlb_huge_update(&l, p); if (htlb_info.need_reload_pte) @@ -2129,6 +2139,14 @@ build_r4000_tlbchange_handler_tail(u32 **p, struct uasm_label **l, uasm_l_leave(l, *p); build_restore_work_registers(p); uasm_i_eret(p); /* return from trap */ +#ifdef CONFIG_CPU_R5900 + /* There should be nothing which can be interpreted as cache instruction. */ + uasm_i_nop(p); + uasm_i_nop(p); + uasm_i_nop(p); + uasm_i_nop(p); + uasm_i_nop(p); +#endif #ifdef CONFIG_64BIT build_get_pgd_vmalloc64(p, l, r, tmp, ptr, not_refill);