From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752337AbcHLG0o convert rfc822-to-8bit (ORCPT ); Fri, 12 Aug 2016 02:26:44 -0400 Received: from mail-oi0-f65.google.com ([209.85.218.65]:33670 "EHLO mail-oi0-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751252AbcHLG0m (ORCPT ); Fri, 12 Aug 2016 02:26:42 -0400 MIME-Version: 1.0 In-Reply-To: References: <1470830763-29189-1-git-send-email-zajec5@gmail.com> <442a71de-7153-2204-2c05-cae6373fdd23@broadcom.com> From: =?UTF-8?B?UmFmYcWCIE1pxYJlY2tp?= Date: Fri, 12 Aug 2016 08:26:40 +0200 Message-ID: Subject: Re: [PATCH V3] clk: bcm: Add driver for Northstar ILP clock To: Jon Mason Cc: Ray Jui , Michael Turquette , Stephen Boyd , linux-clk@vger.kernel.org, BCM Kernel Feedback , =?UTF-8?B?UmFmYcWCIE1pxYJlY2tp?= , Rob Herring , Pawel Moll , Mark Rutland , Ian Campbell , Kumar Gala , Eric Anholt , Florian Fainelli , Jon Mason , Stephen Warren , "open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS" , open list Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 11 August 2016 at 16:25, Jon Mason wrote: > On Thu, Aug 11, 2016 at 4:49 AM, Rafał Miłecki wrote: >> On 10 August 2016 at 20:21, Jon Mason wrote: >>> On Wed, Aug 10, 2016 at 1:44 PM, Ray Jui wrote: >>>> On 8/10/2016 10:28 AM, Rafał Miłecki wrote: >>>>> >>>>> On 10 August 2016 at 19:22, Jon Mason wrote: >>>>>> >>>>>> On Wed, Aug 10, 2016 at 8:05 AM, Rafał Miłecki wrote: >>>>>>> >>>>>>> diff --git a/Documentation/devicetree/bindings/clock/brcm,ns-ilp.txt >>>>>>> b/Documentation/devicetree/bindings/clock/brcm,ns-ilp.txt >>>>>>> new file mode 100644 >>>>>>> index 0000000..a18c73f >>>>>>> --- /dev/null >>>>>>> +++ b/Documentation/devicetree/bindings/clock/brcm,ns-ilp.txt >>>>>>> @@ -0,0 +1,40 @@ >>>>>>> +Broadcom Northstar ILP clock >>>>>>> +============================ >>>>>>> + >>>>>>> +This binding uses the common clock binding: >>>>>>> + Documentation/devicetree/bindings/clock/clock-bindings.txt >>>>>>> + >>>>>>> +This binding is used for ILP clock (sometimes referred as "slow clock") >>>>>>> +on Broadcom Northstar devices using Corex-A7 CPU. >>>>>>> + >>>>>>> +This clock is part of PMU (Power Management Unit), a Broadcom's device >>>>>>> +handing power-related aspects. Please note PMU contains more >>>>>>> subdevices, >>>>>>> +ILP is only one of them. >>>>>>> + >>>>>>> +ILP's rate has to be calculated on runtime and it depends on ALP clock >>>>>>> +which has to be referenced. >>>>>>> + >>>>>>> +Required properties: >>>>>>> +- compatible: "brcm,ns-ilp" >>>>>>> +- reg: iomem address range of PMU (Power Management Unit) >>>>>>> +- reg-names: "pmu", the only needed & supported reg right now >>>>>>> +- clocks: has to reference an ALP clock >>>>>>> +- #clock-cells: should be <0> >>>>>>> + >>>>>>> +Example: >>>>>>> + >>>>>>> +pmu@18012000 { >>>>>>> + compatible = "simple-bus"; >>>>>>> + ranges = <0x00000000 0x18012000 0x00001000>; >>>>>> >>>>>> >>>>>> I don't see a corresponding DT entry in this patch, but 18012000 is >>>>>> the PCI block. So, I am concerned this will collide if used there. >>>>>> >>>>>> I looked at the NS register reference guide, and I cannot find the >>>>>> registers you are trying to reference. Is this supposed to be >>>>>> referencing the LCPLL clock registers in DMU? If so, there is already >>>>>> a driver in there for this (see drivers/clk/bcm/clk-nsp.c). >>>>> >>>>> >>>>> This patch is for BCM53573 family, not BCM4708 family you are looking at. >>>>> >>>>> Found chip with id 53573, rev 0x02 and package 0x01 >>>>> Core 0 found: ChipCommon (manuf 0x4BF, id 0x800, rev 0x36, class 0x0) >>>>> Core 1 found: IEEE 802.11 (manuf 0x4BF, id 0x812, rev 0x38, class 0x0) >>>>> Core 2 found: PCIe Gen 2 (manuf 0x4BF, id 0x501, rev 0x05, class 0x0) >>>>> Core 3 found: ARM CA7 (manuf 0x4BF, id 0x847, rev 0x00, class 0x0) >>>>> Core 4 found: USB 2.0 Host (manuf 0x4BF, id 0x819, rev 0x05, class 0x0) >>>>> Core 5 found: GBit MAC (manuf 0x4BF, id 0x82D, rev 0x08, class 0x0) >>>>> Core 6 found: I2S (manuf 0x4BF, id 0x834, rev 0x06, class 0x0) >>>>> Core 7 found: CNDS DDR2/3 memory controller (manuf 0x4BF, id 0x846, >>>>> rev 0x00, class 0x0) >>>>> Core 8 found: NAND flash controller (manuf 0x4BF, id 0x509, rev 0x01, >>>>> class 0x0) >>>>> Core 9 found: IEEE 802.11 (manuf 0x4BF, id 0x812, rev 0x38, class 0x0) >>>>> Core 10 found: GBit MAC (manuf 0x4BF, id 0x82D, rev 0x08, class 0x0) >>>>> Core 11 found: I2S (manuf 0x4BF, id 0x834, rev 0x06, class 0x0) >>>>> Core 12 found: GCI (manuf 0x4BF, id 0x840, rev 0x08, class 0x0) >>>>> Core 13 found: PMU (manuf 0x4BF, id 0x827, rev 0x1C, class 0x0) >>>>> >>>> >>>> Out of curiosity, I searched the datasheet and found this is a wireless >>>> router SoC done by the WLAN team. It happens to share some peripherals with >>>> other iProc based SoCs. >>>> >>>> I cannot find a code name for this SoC from our internal documents. I guess >>>> that name "Northstar" used here has confused both Jon and me. >>> >>> Ray is right. I just spoke to one of the people here with knowledge >>> of the HW, and this is not related at all to the 4708/9/5301X. It MAY >>> have some of the same peripherals, but the core is different (Cortex >>> A7 instead of A9). >>> >>> I think we are best off to change the name and turn this into a >>> separate device tree, driver base, etc. I wasn't able to get a code >>> name, so perhaps simply call it "BCM53573". >> >> Yes, I said clearly it uses Corex-A7 in the commit message and >> Documentation entry. >> >> Florian already shared his doubts about BCM53573 belonging to the >> Northstar, but I found out [1] that your (Broadcom's) SDK treats it as >> Northstar device: >> >> Asus RT-AC1200G+ >> >> # cat /proc/cpuinfo >> Processor : ARMv7 Processor rev 5 (v7l) >> BogoMIPS : 1795.68 >> Features : swp half thumb fastmult edsp >> CPU implementer : 0x41 >> CPU architecture: 7 >> CPU variant : 0x0 >> CPU part : 0xc07 >> CPU revision : 5 >> >> Hardware : Northstar Prototype >> Revision : 0000 >> Serial : 0000000000000000 >> >> >> It seems Broadcom's WLAN team claims it's a Northstar and you claim >> it's not. Could you discuss this internally and let us know, please? > > I discussed it with a member of the WLAN team prior to my previous > email, which is why I made the previous statement. It is a completely > different SoC than the 5301x family. It appears that someone in > Marketing decided to reuse the name without discussing it with anyone > in WLAN SW. It is a completely different family of products than the > iProc Northstar. If we want to use the Northstar name, then perhaps > we could call it something like "WLAN Northstar". Either way, it > needs to have a different mach-bcm entry. Sorry, it wasn't clear to me initially, thanks for clarification. I'll resend using different prefix. -- Rafał