[PATCH 2/2] memory: omap-gpmc: expand the description of the debug facility
tony at atomide.com
Wed Oct 7 03:41:19 PDT 2015
* Uwe Kleine-König <u.kleine-koenig at pengutronix.de> [151007 00:57]:
> On Wed, Oct 07, 2015 at 10:45:50AM +0300, Roger Quadros wrote:
> > How about this instead?
> > NOTE: Apart from matching the register setup with the bootloader you also need to
> > match the GPMC FCLK frequency used by the bootloader else the GPMC timings
> > won't be identical with the bootloader timings.
> Yeah, sounds better, thanks.
> > Also you might need to build this patch on top of
> > http://article.gmane.org/gmane.linux.kernel/2054796
> I talked to Tony about this patch yesterday on irc, but I didn't find it
> in the archives yet when I sent my mail.
Yes sorry here's a repost with your and Roger's changes folded in and
edited a bit. Probably best to keep them together with this patch.
Does the following look OK to you guys?
From: Tony Lindgren <tony at atomide.com>
Date: Tue, 6 Oct 2015 05:36:17 -0700
Subject: [PATCH] memory: omap-gpmc: Fix unselectable debug option for GPMC
Content-Type: text/plain; charset=UTF-8
Commit 63aa945b1013 ("memory: omap-gpmc: Add Kconfig option for debug")
added a debug option for GPMC, but somehow managed to keep it unselectable.
This probably happened because I had some uncommitted changes and the
GPMC option is selected in the platform specific Kconfig.
Let's also update the description a bit, it does not mention that
enabling the debug option also disables the reset of GPMC controller
during the init as pointed out by Uwe Kleine-König
<u.kleine-koenig at pengutronix.de> and Roger Quadros <rogerq at ti.com>.
Fixes: 63aa945b1013 ("memory: omap-gpmc: Add Kconfig option for debug")
Reported-by: Uwe Kleine-König <u.kleine-koenig at pengutronix.de>
Signed-off-by: Tony Lindgren <tony at atomide.com>
@@ -58,12 +58,18 @@ config OMAP_GPMC
memory drives like NOR, NAND, OneNAND, SRAM.
+ bool "Enable GPMC debug output and skip reset of GPMC during init"
depends on OMAP_GPMC
Enables verbose debugging mostly to decode the bootloader provided
- timings. Enable this during development to configure devices
- connected to the GPMC bus.
+ timings. To preserve the bootloader provided timings, the reset
+ of GPMC is skipped during init. Enable this during development to
+ configure devices connected to the GPMC bus.
+ NOTE: In addition to matching the register setup with the bootloader
+ you also need to match the GPMC FCLK frequency used by the
+ bootloader or else the GPMC timings won't be identical with the
+ bootloader timings.
bool "Marvell EBU Device Bus Controller"
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