From mboxrd@z Thu Jan 1 00:00:00 1970 From: robh@kernel.org (Rob Herring) Date: Wed, 2 Mar 2016 11:57:13 -0600 Subject: [RESPIN 5/6] dt-bindings: EXYNOS: Describe SROMc configuration In-Reply-To: <1456389222-12738-6-git-send-email-pankaj.dubey@samsung.com> References: <1456389222-12738-1-git-send-email-pankaj.dubey@samsung.com> <1456389222-12738-6-git-send-email-pankaj.dubey@samsung.com> Message-ID: <20160302175713.GB11155@rob-hp-laptop> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Thu, Feb 25, 2016 at 02:03:41PM +0530, Pankaj Dubey wrote: > From: Pavel Fedin > > Add documentation for new subnode properties, allowing bank configuration. > Based on u-boot implementation, but heavily reworked. > > Also, fix size of SROMc mapping in the example. Fix it in the previous patch. > CC: devicetree at vger.kernel.org > Signed-off-by: Pavel Fedin > Signed-off-by: Pankaj Dubey > Reviewed-by: Krzysztof Kozlowski > Acked-by: Rob Herring > Signed-off-by: Krzysztof Kozlowski > --- > .../bindings/memory-controllers/exynos-srom.txt | 73 +++++++++++++++++++++- > 1 file changed, 71 insertions(+), 2 deletions(-) > > diff --git a/Documentation/devicetree/bindings/memory-controllers/exynos-srom.txt b/Documentation/devicetree/bindings/memory-controllers/exynos-srom.txt > index 33886d5..e5c18df 100644 > --- a/Documentation/devicetree/bindings/memory-controllers/exynos-srom.txt > +++ b/Documentation/devicetree/bindings/memory-controllers/exynos-srom.txt > @@ -5,8 +5,77 @@ Required properties: > > - reg: offset and length of the register set > > -Example: > +Optional properties: > +The SROM controller can be used to attach external peripherals. In this case > +extra properties, describing the bus behind it, should be specified as below: > + > +- #address-cells: Must be set to 2 to allow device address translation. > + Address is specified as (bank#, offset). > + > +- #size-cells: Must be set to 1 to allow device size passing > + > +- ranges: Must be set up to reflect the memory layout with four integer values > + per bank: > + 0 > + > +Sub-nodes: > +The actual device nodes should be added as subnodes to the SROMc node. These > +subnodes, except regular device specification, should contain the following s/except/in addition to/ > +properties, describing configuration of the relevant SROM bank: > + > +Required properties: > +- reg: bank number, base address (relative to start of the bank) and size of > + the memory mapped for the device. Note that base address will be > + typically 0 as this is the start of the bank. > + > +- samsung,srom-timing : array of 6 integers, specifying bank timings in the > + following order: Tacp, Tcah, Tcoh, Tacc, Tcos, Tacs. > + Each value is specified in cycles and has the following > + meaning and valid range: > + Tacp : Page mode access cycle at Page mode (0 - 15) > + Tcah : Address holding time after CSn (0 - 15) > + Tcoh : Chip selection hold on OEn (0 - 15) > + Tacc : Access cycle (0 - 31, the actual time is N + 1) > + Tcos : Chip selection set-up before OEn (0 - 15) > + Tacs : Address set-up before CSn (0 - 15) > + > +Optional properties: > +- reg-io-width : data width in bytes (1 or 2). If omitted, default of 1 is used. > + > +- samsung,srom-page-mode : page mode configuration for the bank: > + 0 - normal (one data) > + 1 - four data > + If omitted, default of 0 is used. Make this a bool instead. Rob