From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932212AbcFOBaU (ORCPT ); Tue, 14 Jun 2016 21:30:20 -0400 Received: from mail-pa0-f68.google.com ([209.85.220.68]:33324 "EHLO mail-pa0-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752474AbcFOBaO (ORCPT ); Tue, 14 Jun 2016 21:30:14 -0400 From: Andrey Smirnov To: linux-arm-kernel@lists.infradead.org Cc: Russell King , Shawn Guo , Sascha Hauer , Arnd Bergmann , linux-kernel@vger.kernel.org, Andrey Smirnov Subject: [PATCH v2 5/6] i.MX: system.c: Tweak prefetch settings for performance Date: Tue, 14 Jun 2016 18:29:52 -0700 Message-Id: <1465954193-5894-6-git-send-email-andrew.smirnov@gmail.com> X-Mailer: git-send-email 2.5.5 In-Reply-To: <1465954193-5894-1-git-send-email-andrew.smirnov@gmail.com> References: <1465954193-5894-1-git-send-email-andrew.smirnov@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Update Prefetch Control Register settings to match that of Freescale's Linux tree. As the commit e3addf1b773964eac7f797e8538c69481be4279c states (author Nitin Garg): "... set Prefetch offset to 15, since it improves memcpy performance by 35%. Don't enable Incr double Linefill enable since it adversely affects memcpy performance by about 32MB/s and reads by 90MB/s. Tested with 4K to 16MB sized src and dst aligned buffer..." Those results are also corroborated by our own testing. Tested-by: Chris Healy Signed-off-by: Andrey Smirnov --- arch/arm/mach-imx/system.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/arch/arm/mach-imx/system.c b/arch/arm/mach-imx/system.c index f0a9787..9ea01e3 100644 --- a/arch/arm/mach-imx/system.c +++ b/arch/arm/mach-imx/system.c @@ -111,8 +111,12 @@ void __init imx_init_l2cache(void) val = readl_relaxed(l2x0_base + L310_PREFETCH_CTRL); val |= L310_PREFETCH_CTRL_DBL_LINEFILL | L310_PREFETCH_CTRL_INSTR_PREFETCH | - L310_PREFETCH_CTRL_DATA_PREFETCH | - L310_PREFETCH_CTRL_DBL_LINEFILL_INCR; + L310_PREFETCH_CTRL_DATA_PREFETCH; + + /* Set perfetch offset to improve performance */ + val &= ~L310_PREFETCH_CTRL_OFFSET_MASK; + val |= 15; + writel_relaxed(val, l2x0_base + L310_PREFETCH_CTRL); } -- 2.5.5