Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755932Ab3HWRTw (ORCPT ); Fri, 23 Aug 2013 13:19:52 -0400 Received: from mail-db8lp0187.outbound.messaging.microsoft.com ([213.199.154.187]:34585 "EHLO db8outboundpool.messaging.microsoft.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754523Ab3HWRTv convert rfc822-to-8bit (ORCPT ); Fri, 23 Aug 2013 13:19:51 -0400 X-Forefront-Antispam-Report: CIP:149.199.60.83;KIP:(null);UIP:(null);IPV:NLI;H:xsj-gw1;RD:unknown-60-83.xilinx.com;EFVD:NLI X-SpamScore: -4 X-BigFish: VPS-4(zzbb2dI98dIc89bh148cI1432I1418Idb82hzz1f42h208ch1ee6h1de0h1fdah2073h1202h1e76h1d1ah1d2ah1fc6hzz1de098h8275bh1de097hz2fh95h839h93fhd24hf0ah119dh1288h12a5h12a9h12bdh137ah13b6h1441h14ddh1504h1537h153bh162dh1631h1758h18e1h1946h19b5h1b0ah1d0ch1d2eh1d3fh1dfeh1dffh1e1dh1fe8h1ff5h906i1155h192ch) Date: Fri, 23 Aug 2013 10:19:35 -0700 From: =?utf-8?B?U8O2cmVu?= Brinkmann To: Sebastian Hesselbarth , Steffen Trumtrar CC: Mike Turquette , Russell King , Arnd Bergmann , Michal Simek , , , Steffen Trumtrar , Soren Brinkmann Subject: Re: [RFC 17/17] clk: zynq: remove call to of_clk_init References: <1376964271-22715-1-git-send-email-sebastian.hesselbarth@gmail.com> <1376964271-22715-18-git-send-email-sebastian.hesselbarth@gmail.com> <52172BAA.7020009@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Disposition: inline In-Reply-To: <52172BAA.7020009@gmail.com> User-Agent: Mutt/1.5.21 (2010-09-15) X-RCIS-Action: ALLOW Message-ID: Content-Transfer-Encoding: 8BIT X-OriginatorOrg: xilinx.com X-FOPE-CONNECTOR: Id%0$Dn%*$RO%0$TLS%0$FQDN%$TlsDn% Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 5646 Lines: 146 Hi Sebastian, Steffen, On Fri, Aug 23, 2013 at 11:30:18AM +0200, Sebastian Hesselbarth wrote: > On 08/23/13 02:59, Sören Brinkmann wrote: > >On Thu, Aug 22, 2013 at 05:26:47PM -0700, Sören Brinkmann wrote: > >>On Tue, Aug 20, 2013 at 04:04:31AM +0200, Sebastian Hesselbarth wrote: > >>>With arch/arm calling of_clk_init(NULL) from time_init(), we can now > >>>remove it from corresponding drivers/clk code. > >> > >>I think that would break Zynq. > >>If I see this correctly you call of_clk_init() from common code, > >>_before_ the SOC specific time init function is called. > >>The problem is, that we have code setting up a global pointer which is > >>required by zynq_clk_setup() which is triggered when of_clk_init() is > >>called. [ ... ] > thanks for looking into this. I also had a look at the files in > question. Based on Steffen's proposal, I prepared a diff that should do > the trick. It moves zynq_slcr_init() to early_init, instead of reusing > another hook that has magic cow powers (it calls irqchip_init that zynq > also wants sooner or later). > > Also, it removes zynq_clock_init() and let zynq_clk_setup() map the > register itself by finding the node and use of_iomap(). I realized that > clock registers are quite separated within slcr, so you can consider > to have your own node for the clk-provider. As Steffen is proposing > this but mentioned incompatible DT changes, I chose that intermediate > step above. > > It would be great, if you test the diff and prepare a patch out of > it, that I pick-up in the patch set. That way, we also have your > Signed-off on it. I looked into this. Looks like init_early() happens to early. I suspect slab is missing to make zynq_slcr_init() work. So, I moved it into init_irq(). Is there any init_call() type which is called at the correct time? I looked briefly into syscon and regmap, and that does actually look promising and to really fix this mess, I guess we have to wait a little until Steffen finishes his work on it. To facilitate Sebastian's series I came up with the patch below. The problem I have is, I do not really want the clkc to map the registers. They are in the SLCR and the SLCR driver is doing it, hence we should work with what that driver provides - which ideally would be based on regmap and syscon, but we're not there yet. Hence I somehow need to pass the SLCR pointer to the clkc. To avoid accessing the global pointer directly I kept the zynq_clock_init() routine which is called from zynq_slcr_init(). That is the best I could come up with quickly and w/o investing a lot of time to figure out the regmap and syscon stuff, which seems to be handled by Steffen already, anyway. It is essentially a stripped down version of Sebastian's proposal. Sören -----8<--------------------8<-------------------8<------------------- >From bb7a02dad9cc578caf1e21a1b7f45ed602676bfa Mon Sep 17 00:00:00 2001 From: Soren Brinkmann Date: Fri, 23 Aug 2013 09:27:11 -0700 Subject: [PATCH RFC] arm: zynq: Don't call of_clk_init() of_clk_init() has been moved to be called from common code, therefore remove it from Zynq's clock init routine. Since the Zynq's clock setup routine relies on an initialized SLCR, zynq_slcr_init() is moved to init_irq() (note: it must be before init_time() but after slab is available, hence init_early() does not work). Signed-off-by: Soren Brinkmann --- arch/arm/mach-zynq/common.c | 9 ++++----- drivers/clk/zynq/clkc.c | 4 +++- 2 files changed, 7 insertions(+), 6 deletions(-) diff --git a/arch/arm/mach-zynq/common.c b/arch/arm/mach-zynq/common.c index 5f25256..f28046e 100644 --- a/arch/arm/mach-zynq/common.c +++ b/arch/arm/mach-zynq/common.c @@ -19,10 +19,9 @@ #include #include #include -#include -#include #include #include +#include #include #include @@ -58,10 +57,10 @@ static void __init zynq_init_machine(void) of_platform_bus_probe(NULL, zynq_of_bus_ids, NULL); } -static void __init zynq_timer_init(void) +static void __init zynq_init_irq(void) { + irqchip_init(); zynq_slcr_init(); - clocksource_of_init(); } static struct map_desc zynq_cortex_a9_scu_map __initdata = { @@ -104,8 +103,8 @@ static const char * const zynq_dt_match[] = { DT_MACHINE_START(XILINX_EP107, "Xilinx Zynq Platform") .smp = smp_ops(zynq_smp_ops), .map_io = zynq_map_io, + .init_irq = zynq_init_irq, .init_machine = zynq_init_machine, - .init_time = zynq_timer_init, .dt_compat = zynq_dt_match, .restart = zynq_system_reset, MACHINE_END diff --git a/drivers/clk/zynq/clkc.c b/drivers/clk/zynq/clkc.c index 089d3e3..53b851e 100644 --- a/drivers/clk/zynq/clkc.c +++ b/drivers/clk/zynq/clkc.c @@ -206,6 +206,9 @@ static void __init zynq_clk_setup(struct device_node *np) pr_info("Zynq clock init\n"); + if (WARN_ON(!zynq_slcr_base_priv)) + return; + /* get clock output names from DT */ for (i = 0; i < clk_max; i++) { if (of_property_read_string_index(np, "clock-output-names", @@ -532,5 +535,4 @@ CLK_OF_DECLARE(zynq_clkc, "xlnx,ps7-clkc", zynq_clk_setup); void __init zynq_clock_init(void __iomem *slcr_base) { zynq_slcr_base_priv = slcr_base; - of_clk_init(NULL); } -- 1.8.3.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/