From mboxrd@z Thu Jan 1 00:00:00 1970 From: linux@armlinux.org.uk (Russell King - ARM Linux) Date: Mon, 27 Nov 2017 09:19:38 +0000 Subject: [PATCH] arm: l2c: unlock ways when in non-secure mode In-Reply-To: References: <20171126122530.857-1-peng.fan@nxp.com> <20171126131812.GZ31757@n2100.armlinux.org.uk> Message-ID: <20171127091937.GA31757@n2100.armlinux.org.uk> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Sun, Nov 26, 2017 at 11:56:10PM +0000, Peng Fan wrote: > Hi Russell, > > > Subject: Re: [PATCH] arm: l2c: unlock ways when in non-secure mode > > > > On Sun, Nov 26, 2017 at 08:25:30PM +0800, Peng Fan wrote: > > > To boot Linux in Non-secure mode with l2x0, the l2x0 controller is > > > enabled in secure mode and ways locked to make it seems L2 cache > > > disabled during linux boot process. So during l2x0 initialization, > > > need to unlock the ways to make l2x0 could cache data/inst. > > > > Why was this chosen instead of doing what everyone else does? > > I am not aware of how other platform handles the l2x0 unlock in non > secure mode. Could you please share with me what others choose? That's not what I was asking. Everyone else provides a way for the l2x0 controller to be enabled and disabled from non-secure mode. Why have you decided to enable the l2x0 controller and leave it enabled, and then lock down all the cache ways - which means you need the kernel to do something entirely different for your platform. -- RMK's Patch system: http://www.armlinux.org.uk/developer/patches/ FTTC broadband for 0.8mile line in suburbia: sync at 8.8Mbps down 630kbps up According to speedtest.net: 8.21Mbps down 510kbps up