From mboxrd@z Thu Jan 1 00:00:00 1970 From: Russell King - ARM Linux Subject: Re: [PATCH v3] ARM: l2c: add options to overwrite prefetching behavior Date: Fri, 29 May 2015 18:49:58 +0100 Message-ID: <20150529174957.GK2067@n2100.arm.linux.org.uk> References: <1431726751-9169-1-git-send-email-hauke@hauke-m.de> <5568A2ED.4000502@hauke-m.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <5568A2ED.4000502-5/S+JYg5SzeELgA04lAiVw@public.gmane.org> Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Hauke Mehrtens Cc: arnd-r2nGTMty4D4@public.gmane.org, devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, geert+renesas-gXvu3+zWzMSzQB+pC5nmwQ@public.gmane.org, catalin.marinas-5wv7dgnIgG8@public.gmane.org, =?utf-8?B?UmFmYcWCIE1pxYJlY2tp?= List-Id: devicetree@vger.kernel.org On Fri, May 29, 2015 at 07:33:33PM +0200, Hauke Mehrtens wrote: > Will this make it into kernel 4.2 or do I have to do something so that > this will make it into 4.2? I don't see anything wrong with it, but as ever, it needs to end up in the patch system if it's not going to get buried beneath a huge pile of email. Thanks. > > Hauke > > On 05/15/2015 11:52 PM, Hauke Mehrtens wrote: > > These options make it possible to overwrites the data and instruction > > prefetching behavior of the arm pl310 cache controller. > > > > Signed-off-by: Hauke Mehrtens > > --- > > v2: only set prefetch > > v1: set prefetch and aux > > > > Documentation/devicetree/bindings/arm/l2cc.txt | 4 ++++ > > arch/arm/mm/cache-l2x0.c | 20 ++++++++++++++++++++ > > 2 files changed, 24 insertions(+) > > > > diff --git a/Documentation/devicetree/bindings/arm/l2cc.txt b/Documentation/devicetree/bindings/arm/l2cc.txt > > index 0dbabe9..528821a 100644 > > --- a/Documentation/devicetree/bindings/arm/l2cc.txt > > +++ b/Documentation/devicetree/bindings/arm/l2cc.txt > > @@ -67,6 +67,10 @@ Optional properties: > > disable if zero. > > - arm,prefetch-offset : Override prefetch offset value. Valid values are > > 0-7, 15, 23, and 31. > > +- arm,prefetch-data : Enable data prefetch. Enabling prefetching > > + can improve performance. > > +- arm,prefetch-instr : Enable instruction prefetch. Enabling prefetching > > + can improve performance. > > > > Example: > > > > diff --git a/arch/arm/mm/cache-l2x0.c b/arch/arm/mm/cache-l2x0.c > > index e309c8f..1aa970a 100644 > > --- a/arch/arm/mm/cache-l2x0.c > > +++ b/arch/arm/mm/cache-l2x0.c > > @@ -1199,6 +1199,26 @@ static void __init l2c310_of_parse(const struct device_node *np, > > pr_err("L2C-310 OF arm,prefetch-offset property value is missing\n"); > > } > > > > + ret = of_property_read_u32(np, "arm,prefetch-data", &val); > > + if (ret == 0) { > > + if (val) > > + prefetch |= L310_PREFETCH_CTRL_DATA_PREFETCH; > > + else > > + prefetch &= ~L310_PREFETCH_CTRL_DATA_PREFETCH; > > + } else if (ret != -EINVAL) { > > + pr_err("L2C-310 OF arm,prefetch-data property value is missing\n"); > > + } > > + > > + ret = of_property_read_u32(np, "arm,prefetch-instr", &val); > > + if (ret == 0) { > > + if (val) > > + prefetch |= L310_PREFETCH_CTRL_INSTR_PREFETCH; > > + else > > + prefetch &= ~L310_PREFETCH_CTRL_INSTR_PREFETCH; > > + } else if (ret != -EINVAL) { > > + pr_err("L2C-310 OF arm,prefetch-instr property value is missing\n"); > > + } > > + > > l2x0_saved_regs.prefetch_ctrl = prefetch; > > } > > > > -- FTTC broadband for 0.8mile line: currently at 10.5Mbps down 400kbps up according to speedtest.net. -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html