All of lore.kernel.org
 help / color / mirror / Atom feed
From: Vignesh R <vigneshr@ti.com>
To: Tero Kristo <t-kristo@ti.com>, Paul Walmsley <paul@pwsan.com>,
	Thierry Reding <thierry.reding@gmail.com>,
	Rob Herring <robh+dt@kernel.org>, Pawel Moll <pawel.moll@arm.com>,
	Mark Rutland <mark.rutland@arm.com>,
	Ian Campbell <ijc+devicetree@hellion.org.uk>,
	Kumar Gala <galak@codeaurora.org>,
	Benoit Cousson <bcousson@baylibre.com>,
	Tony Lindgren <tony@atomide.com>,
	Russell King <linux@arm.linux.org.uk>,
	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>,
	<linux-arm-kernel@lists.infradead.org>,
	<linux-clk@vger.kernel.org>
Subject: Re: [PATCH 2/5] ARM: OMAP2+: DRA7: Add hwmod entries for PWMSS
Date: Tue, 2 Jun 2015 16:54:10 +0530	[thread overview]
Message-ID: <556D925A.9070708@ti.com> (raw)
In-Reply-To: <556D6781.2090405@ti.com>

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

WARNING: multiple messages have this Message-ID (diff)
From: Vignesh R <vigneshr@ti.com>
To: Tero Kristo <t-kristo@ti.com>, Paul Walmsley <paul@pwsan.com>,
	Thierry Reding <thierry.reding@gmail.com>,
	Rob Herring <robh+dt@kernel.org>, Pawel Moll <pawel.moll@arm.com>,
	Mark Rutland <mark.rutland@arm.com>,
	Ian Campbell <ijc+devicetree@hellion.org.uk>,
	Kumar Gala <galak@codeaurora.org>,
	Benoit Cousson <bcousson@baylibre.com>,
	Tony Lindgren <tony@atomide.com>,
	Russell King <linux@arm.linux.org.uk>,
	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,
	linux-arm-kernel@lists.infradead.org, linux-clk@vger.kernel.org
Subject: Re: [PATCH 2/5] ARM: OMAP2+: DRA7: Add hwmod entries for PWMSS
Date: Tue, 2 Jun 2015 16:54:10 +0530	[thread overview]
Message-ID: <556D925A.9070708@ti.com> (raw)
In-Reply-To: <556D6781.2090405@ti.com>

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


WARNING: multiple messages have this Message-ID (diff)
From: vigneshr@ti.com (Vignesh R)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH 2/5] ARM: OMAP2+: DRA7: Add hwmod entries for PWMSS
Date: Tue, 2 Jun 2015 16:54:10 +0530	[thread overview]
Message-ID: <556D925A.9070708@ti.com> (raw)
In-Reply-To: <556D6781.2090405@ti.com>

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

  reply	other threads:[~2015-06-02 11:24 UTC|newest]

Thread overview: 30+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-06-01 11:53 [PATCH 0/5] Add support for PWMSS on DRA7 Vignesh R
2015-06-01 11:53 ` Vignesh R
2015-06-01 11:53 ` Vignesh R
2015-06-01 11:53 ` [PATCH 1/5] ARM: OMAP2+: DRA7: clockdomain: change l4per2_7xx_clkdm to SW_WKUP Vignesh R
2015-06-01 11:53   ` Vignesh R
2015-06-01 11:53   ` Vignesh R
2015-06-01 11:53 ` [PATCH 2/5] ARM: OMAP2+: DRA7: Add hwmod entries for PWMSS Vignesh R
2015-06-01 11:53   ` Vignesh R
2015-06-01 11:53   ` Vignesh R
2015-06-02  8:21   ` Tero Kristo
2015-06-02  8:21     ` Tero Kristo
2015-06-02  8:21     ` Tero Kristo
2015-06-02 11:24     ` Vignesh R [this message]
2015-06-02 11:24       ` Vignesh R
2015-06-02 11:24       ` Vignesh R
2015-06-01 11:53 ` [PATCH 3/5] ARM: dts: DRA7: Add TBCLK " Vignesh R
2015-06-01 11:53   ` Vignesh R
2015-06-01 11:53   ` Vignesh R
2015-06-02  8:22   ` Tero Kristo
2015-06-02  8:22     ` Tero Kristo
2015-06-02  8:22     ` Tero Kristo
2015-06-02 11:23     ` Vignesh R
2015-06-02 11:23       ` Vignesh R
2015-06-02 11:23       ` Vignesh R
2015-06-01 11:53 ` [PATCH 4/5] clk: ti: DRA7: Add tbclk data for ehrpwm Vignesh R
2015-06-01 11:53   ` Vignesh R
2015-06-01 11:53   ` Vignesh R
2015-06-01 11:53 ` [PATCH 5/5] ARM: dts: DRA7: Add dt nodes for PWMSS Vignesh R
2015-06-01 11:53   ` Vignesh R
2015-06-01 11:53   ` Vignesh R

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=556D925A.9070708@ti.com \
    --to=vigneshr@ti.com \
    --cc=bcousson@baylibre.com \
    --cc=devicetree@vger.kernel.org \
    --cc=galak@codeaurora.org \
    --cc=ijc+devicetree@hellion.org.uk \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-clk@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-omap@vger.kernel.org \
    --cc=linux-pwm@vger.kernel.org \
    --cc=linux@arm.linux.org.uk \
    --cc=mark.rutland@arm.com \
    --cc=mturquette@linaro.org \
    --cc=paul@pwsan.com \
    --cc=pawel.moll@arm.com \
    --cc=robh+dt@kernel.org \
    --cc=sboyd@codeaurora.org \
    --cc=t-kristo@ti.com \
    --cc=thierry.reding@gmail.com \
    --cc=tony@atomide.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.