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Date: Tue, 2 Jun 2015 16:54:10 +0530
From: Vignesh R <vigneshr@ti.com>
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To: Tero Kristo <t-kristo@ti.com>, Paul Walmsley <paul@pwsan.com>,
        Thierry
 Reding <thierry.reding@gmail.com>,
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        Russell
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        Mike Turquette <mturquette@linaro.org>,
        Stephen Boyd <sboyd@codeaurora.org>
CC: <linux-pwm@vger.kernel.org>, <devicetree@vger.kernel.org>,
        <linux-kernel@vger.kernel.org>, <linux-omap@vger.kernel.org>,
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Subject: Re: [PATCH 2/5] ARM: OMAP2+: DRA7: Add hwmod entries for PWMSS
References: <1433159614-437-1-git-send-email-vigneshr@ti.com> <1433159614-437-3-git-send-email-vigneshr@ti.com> <556D6781.2090405@ti.com>
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List-ID: <linux-clk.vger.kernel.org>

Hi Tero,

On Tuesday 02 June 2015 01:51 PM, Tero Kristo wrote:
> On 06/01/2015 02:53 PM, Vignesh R wrote:
>> Add hwmod entries for the PWMSS on DRA7.
> 
> Can you provide some documentation references for this data?
> 
> I was looking at the TRM and at least the main_clk selection is somewhat
> unclear to me.

As per AM57x TRM SPRUHZ6, October 2014, Section 29.1.3 Table 29-4.
source signal as L4PER2_L3_GICLK but it is actually equal to
L4PER2_L3_GICLK/2. l4_root_clock_div is fixed-factored clock equal to
L4PER2_L3_GICLK/2 (l3_iclk_div/2 in Linux clock dt). The TRM does'nt
show factor of by 2. I will forward you an internal documentation that
talks about this.

I also measured the frequencies of PWM waveforms using oscilloscope and
it matches above observation.

I will update the patch description in v2.

Regards
Vignesh