From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932525AbbLBBlz (ORCPT ); Tue, 1 Dec 2015 20:41:55 -0500 Received: from mailout3.samsung.com ([203.254.224.33]:38154 "EHLO mailout3.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932424AbbLBBlu (ORCPT ); Tue, 1 Dec 2015 20:41:50 -0500 MIME-version: 1.0 Content-type: text/plain; charset=UTF-8 X-AuditID: cbfee68f-f793a6d000001364-eb-565e4c5c8e5a Content-transfer-encoding: 8BIT Message-id: <565E4C5B.7040000@samsung.com> Date: Wed, 02 Dec 2015 10:41:47 +0900 From: Chanwoo Choi User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.6.0 To: Rob Herring Cc: myungjoo.ham@samsung.com, kyungmin.park@samsung.com, kgene@kernel.org, k.kozlowski@samsung.com, pawel.moll@arm.com, mark.rutland@arm.com, ijc+devicetree@hellion.org.uk, galak@codeaurora.org, linux@arm.linux.org.uk, tjakobi@math.uni-bielefeld.de, linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org, linux-samsung-soc@vger.kernel.org, devicetree@vger.kernel.org Subject: Re: [RFC PATCH 09/15] PM / devfreq: exynos: Update documentation for bus devices using passive governor References: <1448545659-32287-1-git-send-email-cw00.choi@samsung.com> <1448545659-32287-10-git-send-email-cw00.choi@samsung.com> <20151130211453.GA29423@rob-hp-laptop> In-reply-to: <20151130211453.GA29423@rob-hp-laptop> X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFrrCIsWRmVeSWpSXmKPExsWyRsSkUDfGJy7MYMNyHov5R86xWvS/Wchq ce7VSkaL1y8MLfofv2a2ONv0ht3i8q45bBafe48wWsw4v4/J4vZlXoul1y8CGY0r2CwmTF/L YvF/zw52i7bVH1gd+D3WzFvD6NHS3MPmcbmvl8lj5fIvbB6bVnWyefw7xu7Rt2UVo8fnTXIB HFFcNimpOZllqUX6dglcGadff2EvOKJasWtpE3sD43LZLkZODgkBE4nNt7rYIGwxiQv31gPZ XBxCAisYJSauWswIU/T6Qi87RGIpo0TjpiNMIAleAUGJH5PvsXQxcnAwC8hLHLmUDRJmFlCX mDRvETNE/QNGidPXLrFA1GtJTJn+mhWknkVAVeL5fzuQMBtQeP+LG2wgYVGBCInuE5UgYREB RYnfbdNYQcYwC/xkkmi4tA/sUGGBIomVC5+CjRQSWA00vzkPxOYUMJZoX/2EHeLmhRwSa/rB 5rMICEh8m3wI7EwJAVmJTQeYIUokJQ6uuMEygVFsFpJnZiE8MwvJMwsYmVcxiqYWJBcUJ6UX GesVJ+YWl+al6yXn525iBEb26X/P+ncw3j1gfYhRgINRiYd3BU9cmBBrYllxZe4hRlOgIyYy S4km5wPTR15JvKGxmZGFqYmpsZG5pZmSOO9CqZ/BQgLpiSWp2ampBalF8UWlOanFhxiZODil GhizylgDH53uZtq6mqPtnsbzCnHte91rJt8onKMqy/jHTOyvw2XuqQfeiu/8+/VL57Qw7qxn 929Mit7YkzBxUXfOrlWnlnr++1LJk9P/gOdI2Pl9l2OUt/L9eyzN/F340LGyYHnB3f5OjlNW pE2zDvta9NVk09HfK03+btzGLdh7bvqjni8FRUf9lFiKMxINtZiLihMB2zncW+cCAAA= X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFlrEKsWRmVeSWpSXmKPExsVy+t9jAd0Yn7gwg1crWS3mHznHatH/ZiGr xblXKxktXr8wtOh//JrZ4mzTG3aLy7vmsFl87j3CaDHj/D4mi9uXeS2WXr8IZDSuYLOYMH0t i8X/PTvYLdpWf2B14PdYM28No0dLcw+bx+W+XiaPlcu/sHlsWtXJ5vHvGLtH35ZVjB6fN8kF cEQ1MNpkpCampBYppOYl56dk5qXbKnkHxzvHm5oZGOoaWlqYKynkJeam2iq5+AToumXmAN2u pFCWmFMKFApILC5W0rfDNCE0xE3XAqYxQtc3JAiux8gADSSsYcw4/foLe8ER1YpdS5vYGxiX y3YxcnJICJhIvL7Qyw5hi0lcuLeerYuRi0NIYCmjROOmI0wgCV4BQYkfk++xdDFycDALyEsc uZQNEmYWUJeYNG8RM0T9A0aJ09cusUDUa0lMmf6aFaSeRUBV4vl/O5AwG1B4/4sbbCBhUYEI ie4TlSBhEQFFid9t01hBxjAL/GSSaLi0jw0kISxQJLFy4VOwkUICq4HmN+eB2JwCxhLtq5+w T2AUmIXkulkI181Cct0CRuZVjBKpBckFxUnpuUZ5qeV6xYm5xaV56XrJ+bmbGMHp45n0DsbD u9wPMQpwMCrx8K7giQsTYk0sK67MPcQowcGsJMLrJQMU4k1JrKxKLcqPLyrNSS0+xGgK9N5E ZinR5HxgassriTc0NjEzsjQyN7QwMjZXEufddykyTEggPbEkNTs1tSC1CKaPiYNTqoFRUW0r w6rvzvbL25wVtKwZUvyu/pxbUXxog6XOY/Z/OmV7FXnmeWaXPD14bVb48ZwloWbxp6OOC8bM b7i+SL7Udn0Lb0fFOebKcKlNcVsktAVSXt67az5PTH+7se/+dTFLsx0MOk/7OIbdcc2/tJ8j SGO20oXNPW6nf7R9Kl1QoDj91PpUhj4lluKMREMt5qLiRADhAym1NQMAAA== DLP-Filter: Pass X-MTR: 20000000000000000@CPGS X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Rob, I'm sorry for delay reply due to the problem of email system on the company. On 2015년 12월 01일 06:14, Rob Herring wrote: > On Thu, Nov 26, 2015 at 10:47:33PM +0900, Chanwoo Choi wrote: >> This patch updates the documentation for passive bus devices and adds the >> detailed example of Exynos3250. >> >> Signed-off-by: Chanwoo Choi >> --- >> .../devicetree/bindings/devfreq/exynos-bus.txt | 226 ++++++++++++++++++++- >> 1 file changed, 223 insertions(+), 3 deletions(-) >> >> diff --git a/Documentation/devicetree/bindings/devfreq/exynos-bus.txt b/Documentation/devicetree/bindings/devfreq/exynos-bus.txt >> index 5d90623bd173..c4a6fe30075e 100644 >> --- a/Documentation/devicetree/bindings/devfreq/exynos-bus.txt >> +++ b/Documentation/devicetree/bindings/devfreq/exynos-bus.txt >> @@ -12,18 +12,23 @@ SoC has the different sub-blocks. So, this difference should be specified >> in devicetree file instead of each device driver. In result, this driver >> is able to support the bus frequency for all Exynos SoCs. >> >> -Required properties for bus device: >> +Required properties for all bus devices: >> - compatible: Should be "samsung,exynos-bus". >> - clock-names : the name of clock used by the bus, "bus". >> - clocks : phandles for clock specified in "clock-names" property. >> - #clock-cells: should be 1. >> - operating-points-v2: the OPP table including frequency/voltage information >> to support DVFS (Dynamic Voltage/Frequency Scaling) feature. >> + >> +Required properties for only parent bus device: >> - vdd-supply: the regulator to provide the buses with the voltage. >> - devfreq-events: the devfreq-event device to monitor the curret utilization >> of buses. >> >> -Optional properties for bus device: >> +Required properties for only passive bus device: >> +- devfreq: the parent bus device. >> + >> +Optional properties for only parent bus device: >> - exynos,saturation-ratio: the percentage value which is used to calibrate >> the performance count againt total cycle count. >> >> @@ -32,7 +37,19 @@ Example1: >> power line (regulator). The MIF (Memory Interface) AXI bus is used to >> transfer data between DRAM and CPU and uses the VDD_MIF regualtor. >> >> - - power line(VDD_MIF) --> bus for DMC block (dmc clock) >> + - MIF (Memory Interface) block >> + : VDD_MIF |--- DMC >> + >> + - INT (Internal) block >> + : VDD_INT |--- LEFTBUS |--- PERIL >> + | (parent) |--- MFC >> + | |--- G3D >> + | >> + |--- RIGHTBUS |--- FSYS >> + |--- LCD0 >> + |--- PERIR >> + |--- ISP >> + |--- CAM > > I would expect the DT to mirror this topology which doesn't seem to be > the case in the example. You're right. The above topology is not appropriate to show the correlation between power line and sub blocks. I'll modify it as following. The all blocks which are included in the INT (internal) block share the one power line (VDD_INT). VDD_MIF |--- DMC VDD_INT |--- LEFTBUS |--- PERIL |--- MFC |--- G3D |--- RIGHTBUS |--- FSYS |--- LCD0 |--- PERIR |--- ISP |--- CAM > > >> - MIF bus's frequency/voltage table >> ----------------------- >> @@ -45,6 +62,20 @@ Example1: >> |L5| 400000 |875000 | >> ----------------------- >> >> + - INT bus's frequency/voltage table >> + ----------------------------------------------------------------------- >> + |Lv| Freq | Voltage | >> + ----------------------------------------------------------------------- >> + | |LEFTBUS|RIGHTBUS|LCD0 |FSYS |MCUISP |ISP |PERIL |VDD_INT | >> + | |*parent|passive |passive|passive|passive|passive|passive| | >> + ----------------------------------------------------------------------- >> + |L1|50000 |50000 |50000 |50000 |50000 |50000 |50000 |900000 | >> + |L2|80000 |80000 |80000 |80000 |80000 |80000 |80000 |900000 | >> + |L3|100000 |100000 |100000 |100000 |100000 |100000 |100000 |1000000 | >> + |L4|133000 |133000 |133000 |133000 |200000 |200000 | |1000000 | >> + |L5|200000 |200000 |200000 |200000 |400000 |300000 | |1000000 | >> + ----------------------------------------------------------------------- > > Do you really have 5 states? It look like there are 2 to me because the > OPP tables only really need to have the max freq at each voltage point. I'm sure. The OPP allow OPP table to add the same voltage for each OPP entry. Instead, OPP don't permit adding the duplicate frequency. If OPP table includes the different frequency as OPP entry, there is no problem. It is tested. Regards, Chanwoo Choi