From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mark Rutland Subject: Re: [PATCH v2 6/9] arm: mediatek: enable gpt6 on boot up to make arch timer working Date: Mon, 18 Aug 2014 16:45:48 +0100 Message-ID: <20140818154548.GA3302@leverpostej> References: <1408373917-10002-1-git-send-email-matthias.bgg@gmail.com> <1408373917-10002-7-git-send-email-matthias.bgg@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <1408373917-10002-7-git-send-email-matthias.bgg@gmail.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=m.gmane.org@lists.infradead.org To: Matthias Brugger Cc: "thomas.petazzoni@free-electrons.com" , "anders.berg@lsi.com" , "linux@arm.linux.org.uk" , "arnd@arndb.de" , Pawel Moll , "ijc+devicetree@hellion.org.uk" , "linus.walleij@linaro.org" , "srv_yingjoe.chen@mediatek.com" , "heiko@sntech.de" , "linux-kernel@vger.kernel.org" , "stefan@agner.ch" , "devicetree@vger.kernel.org" , "robh+dt@kernel.org" , "galak@codeaurora.org" , "olof@lixom.net" , "swarren@nvidia.com" , "maxime.ripard@free-electrons.com" , sebastian.hesselbart List-Id: devicetree@vger.kernel.org Hi Matthias, On Mon, Aug 18, 2014 at 03:58:34PM +0100, Matthias Brugger wrote: > We enable GTP6 which ungates the arch timer clock. Apart we write the > frequency with which the timer is running in the CNTFREQ register. We don't seem to set CNTFRQ below. Does it happen to have a consistent value on current versions of the bootloader? > In the future this should be done in the bootloader. Do we know how far in the future that's likely to be? What's the plan for this code when such a bootloader becomes available? Thanks, Mark. > Signed-off-by: Matthias Brugger > --- > arch/arm/mach-mediatek/mediatek.c | 26 ++++++++++++++++++++++++++ > 1 file changed, 26 insertions(+) > > diff --git a/arch/arm/mach-mediatek/mediatek.c b/arch/arm/mach-mediatek/mediatek.c > index f2acf07..2989f18 100644 > --- a/arch/arm/mach-mediatek/mediatek.c > +++ b/arch/arm/mach-mediatek/mediatek.c > @@ -16,6 +16,31 @@ > */ > #include > #include > +#include > +#include > +#include > + > +#define TIMER_CTRL_OP_FREERUN 0x30 > +#define TIMER_CTRL_ENABLE 0x01 > + > +#define GPT6_CON_MT65xx 0x10008060 > + > +static void __init mediatek_timer_init(void) > +{ > + static void __iomem *gpt_base; > + > + if (of_machine_is_compatible("mediatek,mt6589")) { > + /* turn on GPT6 which ungates arch timer clocks */ > + gpt_base = ioremap(GPT6_CON_MT65xx, 0x04); > + } > + > + /* enabel clock and set to free-run */ > + if (gpt_base) > + writel(TIMER_CTRL_OP_FREERUN | TIMER_CTRL_ENABLE, gpt_base); > + > + of_clk_init(NULL); > + clocksource_of_init(); > +}; > > static const char * const mediatek_board_dt_compat[] = { > "mediatek,mt6589", > @@ -24,4 +49,5 @@ static const char * const mediatek_board_dt_compat[] = { > > DT_MACHINE_START(MEDIATEK_DT, "Mediatek Cortex-A7 (Device Tree)") > .dt_compat = mediatek_board_dt_compat, > + .init_time = mediatek_timer_init, > MACHINE_END > -- > 1.7.9.5 > >