From: "Lennart Sorensen" <lsorense@csclub.uwaterloo.ca> To: Nishanth Menon <nm@ti.com> Cc: Tony Lindgren <tony@atomide.com>, Linus Walleij <linus.walleij@linaro.org>, "linux-gpio@vger.kernel.org" <linux-gpio@vger.kernel.org>, "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>, "devicetree@vger.kernel.org" <devicetree@vger.kernel.org>, Linux-OMAP <linux-omap@vger.kernel.org>, "linux-arm-kernel@lists.infradead.org" <linux-arm-kernel@lists.infradead.org>, Lokesh Vutla <lokeshvutla@ti.com> Subject: Re: [PATCH 1/2] pinctrl: bindings: pinctrl: Add support for TI's IODelay configuration Date: Wed, 15 Apr 2015 14:44:54 -0400 [thread overview] Message-ID: <20150415184454.GT29558@csclub.uwaterloo.ca> (raw) In-Reply-To: <552E9714.10001@ti.com> On Wed, Apr 15, 2015 at 11:51:32AM -0500, Nishanth Menon wrote: > I am yet to post a new revision to this series - few other stuff got > in the way. IODelay driver in no way removes the constraint that the > SoC architecture has - most of the pins still need to be muxed in > bootloader - we cannot escape that. The reasoning for doing the mux in > bootloader is independent of the need for iodelay. > > Reasoning for mux in bootloader is because the mux and pull fields are > glitchy - much more than previous generations of TI SoCs and > significantly long enough to cause issues depending on the pins being > muxed. Well if we know glitching is NOT an issue on our boards, then we don't have to do anything in the boot loader other than the basic setup for the serial console and emmc and SD, which has always been necesary. I consider moving the mux setup to the bootloader a terrible design and won't go along with it. We make sure all external devices have reset lines being held while the pinmux is being setup, so glitching is a non issue. > Reasoning for iodelay is different - it is a hardware block meant to > control the timing of signals in a particular signal path to ensure > that specification compliance is met. > > Lets try not to mix the two. Well I was told by multiple people from TI that the reason for moving the pinmux setup to the bootloader was because of the iodelay issue, so you will have to get the message made clear within TI then. -- Len Sorensen
WARNING: multiple messages have this Message-ID (diff)
From: lsorense@csclub.uwaterloo.ca (Lennart Sorensen) To: linux-arm-kernel@lists.infradead.org Subject: [PATCH 1/2] pinctrl: bindings: pinctrl: Add support for TI's IODelay configuration Date: Wed, 15 Apr 2015 14:44:54 -0400 [thread overview] Message-ID: <20150415184454.GT29558@csclub.uwaterloo.ca> (raw) In-Reply-To: <552E9714.10001@ti.com> On Wed, Apr 15, 2015 at 11:51:32AM -0500, Nishanth Menon wrote: > I am yet to post a new revision to this series - few other stuff got > in the way. IODelay driver in no way removes the constraint that the > SoC architecture has - most of the pins still need to be muxed in > bootloader - we cannot escape that. The reasoning for doing the mux in > bootloader is independent of the need for iodelay. > > Reasoning for mux in bootloader is because the mux and pull fields are > glitchy - much more than previous generations of TI SoCs and > significantly long enough to cause issues depending on the pins being > muxed. Well if we know glitching is NOT an issue on our boards, then we don't have to do anything in the boot loader other than the basic setup for the serial console and emmc and SD, which has always been necesary. I consider moving the mux setup to the bootloader a terrible design and won't go along with it. We make sure all external devices have reset lines being held while the pinmux is being setup, so glitching is a non issue. > Reasoning for iodelay is different - it is a hardware block meant to > control the timing of signals in a particular signal path to ensure > that specification compliance is met. > > Lets try not to mix the two. Well I was told by multiple people from TI that the reason for moving the pinmux setup to the bootloader was because of the iodelay issue, so you will have to get the message made clear within TI then. -- Len Sorensen
next prev parent reply other threads:[~2015-04-15 18:44 UTC|newest] Thread overview: 61+ messages / expand[flat|nested] mbox.gz Atom feed top 2015-03-04 0:00 [PATCH 0/2] pinctrl: Introduce support for iodelay module in TI SoCs Nishanth Menon 2015-03-04 0:00 ` Nishanth Menon 2015-03-04 0:00 ` Nishanth Menon 2015-03-04 0:00 ` [PATCH 1/2] pinctrl: bindings: pinctrl: Add support for TI's IODelay configuration Nishanth Menon 2015-03-04 0:00 ` Nishanth Menon 2015-03-04 0:00 ` Nishanth Menon 2015-03-10 10:39 ` Linus Walleij 2015-03-10 10:39 ` Linus Walleij 2015-03-10 10:39 ` Linus Walleij 2015-03-10 15:06 ` Nishanth Menon 2015-03-10 15:06 ` Nishanth Menon 2015-03-10 15:06 ` Nishanth Menon 2015-03-10 15:33 ` Tony Lindgren 2015-03-10 15:33 ` Tony Lindgren 2015-03-10 15:33 ` Tony Lindgren 2015-03-10 17:25 ` Nishanth Menon 2015-03-10 17:25 ` Nishanth Menon 2015-03-10 17:25 ` Nishanth Menon 2015-03-10 17:31 ` Tony Lindgren 2015-03-10 17:31 ` Tony Lindgren 2015-03-10 17:31 ` Tony Lindgren 2015-03-10 18:33 ` Nishanth Menon 2015-03-10 18:33 ` Nishanth Menon 2015-03-10 18:33 ` Nishanth Menon 2015-03-10 19:20 ` Nishanth Menon 2015-03-10 19:20 ` Nishanth Menon 2015-03-10 19:20 ` Nishanth Menon 2015-03-18 1:30 ` Linus Walleij 2015-03-18 1:30 ` Linus Walleij 2015-03-18 1:30 ` Linus Walleij 2015-03-18 1:41 ` Tony Lindgren 2015-03-18 1:41 ` Tony Lindgren 2015-03-18 1:41 ` Tony Lindgren 2015-04-15 1:29 ` Lennart Sorensen 2015-04-15 1:29 ` Lennart Sorensen 2015-04-15 1:29 ` Lennart Sorensen [not found] ` <20150415012910.GA29560-1wCw9BSqJbv44Nm34jS7GywD8/FfD2ys@public.gmane.org> 2015-04-15 16:51 ` Nishanth Menon 2015-04-15 16:51 ` Nishanth Menon 2015-04-15 16:51 ` Nishanth Menon 2015-04-15 18:44 ` Lennart Sorensen [this message] 2015-04-15 18:44 ` Lennart Sorensen 2015-04-15 18:44 ` Lennart Sorensen 2015-04-15 18:53 ` Nishanth Menon 2015-04-15 18:53 ` Nishanth Menon 2015-04-15 18:53 ` Nishanth Menon 2015-03-04 0:00 ` [PATCH 2/2] pinctrl: Introduce TI IOdelay configuration driver Nishanth Menon 2015-03-04 0:00 ` Nishanth Menon 2015-03-04 0:00 ` Nishanth Menon 2015-03-04 22:58 ` Paul Bolle 2015-03-04 22:58 ` Paul Bolle 2015-03-04 22:58 ` Tony Lindgren 2015-03-04 22:58 ` Tony Lindgren 2015-03-05 2:22 ` Nishanth Menon 2015-03-05 2:22 ` Nishanth Menon 2015-03-05 2:22 ` Nishanth Menon 2015-03-10 11:03 ` Linus Walleij 2015-03-10 11:03 ` Linus Walleij 2015-03-10 11:03 ` Linus Walleij 2015-03-11 12:39 ` Nishanth Menon 2015-03-11 12:39 ` Nishanth Menon 2015-03-11 12:39 ` Nishanth Menon
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=20150415184454.GT29558@csclub.uwaterloo.ca \ --to=lsorense@csclub.uwaterloo.ca \ --cc=devicetree@vger.kernel.org \ --cc=linus.walleij@linaro.org \ --cc=linux-arm-kernel@lists.infradead.org \ --cc=linux-gpio@vger.kernel.org \ --cc=linux-kernel@vger.kernel.org \ --cc=linux-omap@vger.kernel.org \ --cc=lokeshvutla@ti.com \ --cc=nm@ti.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: linkBe 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.