| Message ID | 20180821143152.32293-9-ricardo.ribalda@gmail.com |
|---|---|
| State | Changes Requested, archived |
| Headers | show |
| Series | None | expand |
On Tue, Aug 21, 2018 at 04:31:52PM +0200, Ricardo Ribalda Delgado wrote: > Add documentation for gpio-addr-flash. This binding allow creating > flash devices that are paged using GPIOs. > > Cc: devicetree@vger.kernel.org > Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com> > --- > .../bindings/mtd/gpio-addr-flash.txt | 46 +++++++++++++++++++ > 1 file changed, 46 insertions(+) > create mode 100644 Documentation/devicetree/bindings/mtd/gpio-addr-flash.txt > > diff --git a/Documentation/devicetree/bindings/mtd/gpio-addr-flash.txt b/Documentation/devicetree/bindings/mtd/gpio-addr-flash.txt > new file mode 100644 > index 000000000000..4279e8cad09b > --- /dev/null > +++ b/Documentation/devicetree/bindings/mtd/gpio-addr-flash.txt > @@ -0,0 +1,46 @@ > +Memory Mapped flash with some address lines addressed using GPIOs That's ugly... > + > +Handle the case where a flash device is mostly addressed using physical > +line and supplemented by GPIOs. This way you can hook up say a 8MiB flash > +to a 2MiB memory range and use the GPIOs to select a particular range. > + > + - compatible : "cfi-gpio-addr-flash" Why a new compatible? Shouldn't just adding some address gpios to an existing flash device binding be sufficient? > + - reg : Address range of the mtd chip that is memory mapped, this is, > + on the previous example 2MiB. > + - bank-width : Width (in bytes) of the bank. Equal to the > + device width times the number of interleaved chips. > + - probe-type : (optional) "cfi_probe", "jedec_probe". How the mtd chip > + is going to be probed. If omitted, assumed to be equal to "cfi_probe". > + - #address-cells, #size-cells : Must be present if the device has > + sub-nodes representing partitions (see below). In this case > + both #address-cells and #size-cells must be equal to 1. > + > +The device tree may optionally contain sub-nodes describing partitions of the > +address space. See partition.txt for more detail. > + > +Example: > + > + cfi_flash_0: cfi_flash { > + #address-cells = <1>; > + #size-cells = <1>; > + compatible = "cfi-gpio-addr-flash"; > + bank-width = <2>; > + reg = < 0x00300000 0x00200000 >; > + gpios = <&gpio_0 3 0>, <&gpio_0 4 0>; > + partition@0 { > + reg = < 0x0 0x200000 >; > + label = "Golden Bitstream"; > + }; > + partition@200000 { > + reg = < 0x200000 0x200000 >; > + label = "User Bitstream"; > + }; > + partition@400000 { > + reg = < 0x400000 0x200000 >; > + label = "V4L Controls"; > + }; > + partition@600000 { > + reg = < 0x600000 0x200000 >; > + label = "Production Data"; > + }; > + } ; > -- > 2.18.0 >
aHi Robb On Fri, Aug 31, 2018 at 2:17 PM Rob Herring <robh@kernel.org> wrote: > > On Tue, Aug 21, 2018 at 04:31:52PM +0200, Ricardo Ribalda Delgado wrote: > > Add documentation for gpio-addr-flash. This binding allow creating > > flash devices that are paged using GPIOs. > > > > Cc: devicetree@vger.kernel.org > > Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com> > > --- > > .../bindings/mtd/gpio-addr-flash.txt | 46 +++++++++++++++++++ > > 1 file changed, 46 insertions(+) > > create mode 100644 Documentation/devicetree/bindings/mtd/gpio-addr-flash.txt > > > > diff --git a/Documentation/devicetree/bindings/mtd/gpio-addr-flash.txt b/Documentation/devicetree/bindings/mtd/gpio-addr-flash.txt > > new file mode 100644 > > index 000000000000..4279e8cad09b > > --- /dev/null > > +++ b/Documentation/devicetree/bindings/mtd/gpio-addr-flash.txt > > @@ -0,0 +1,46 @@ > > +Memory Mapped flash with some address lines addressed using GPIOs > > That's ugly... > If hw was perfect there would be no firmware engineers in the world :P > > + > > +Handle the case where a flash device is mostly addressed using physical > > +line and supplemented by GPIOs. This way you can hook up say a 8MiB flash > > +to a 2MiB memory range and use the GPIOs to select a particular range. > > + > > + - compatible : "cfi-gpio-addr-flash" > > Why a new compatible? Shouldn't just adding some address gpios to an > existing flash device binding be sufficient? Because today there are handled by two different drivers Thanks! > > > + - reg : Address range of the mtd chip that is memory mapped, this is, > > + on the previous example 2MiB. > > + - bank-width : Width (in bytes) of the bank. Equal to the > > + device width times the number of interleaved chips. > > + - probe-type : (optional) "cfi_probe", "jedec_probe". How the mtd chip > > + is going to be probed. If omitted, assumed to be equal to "cfi_probe". > > + - #address-cells, #size-cells : Must be present if the device has > > + sub-nodes representing partitions (see below). In this case > > + both #address-cells and #size-cells must be equal to 1. > > + > > +The device tree may optionally contain sub-nodes describing partitions of the > > +address space. See partition.txt for more detail. > > + > > +Example: > > + > > + cfi_flash_0: cfi_flash { > > + #address-cells = <1>; > > + #size-cells = <1>; > > + compatible = "cfi-gpio-addr-flash"; > > + bank-width = <2>; > > + reg = < 0x00300000 0x00200000 >; > > + gpios = <&gpio_0 3 0>, <&gpio_0 4 0>; > > + partition@0 { > > + reg = < 0x0 0x200000 >; > > + label = "Golden Bitstream"; > > + }; > > + partition@200000 { > > + reg = < 0x200000 0x200000 >; > > + label = "User Bitstream"; > > + }; > > + partition@400000 { > > + reg = < 0x400000 0x200000 >; > > + label = "V4L Controls"; > > + }; > > + partition@600000 { > > + reg = < 0x600000 0x200000 >; > > + label = "Production Data"; > > + }; > > + } ; > > -- > > 2.18.0 > >
diff --git a/Documentation/devicetree/bindings/mtd/gpio-addr-flash.txt b/Documentation/devicetree/bindings/mtd/gpio-addr-flash.txt new file mode 100644 index 000000000000..4279e8cad09b --- /dev/null +++ b/Documentation/devicetree/bindings/mtd/gpio-addr-flash.txt @@ -0,0 +1,46 @@ +Memory Mapped flash with some address lines addressed using GPIOs + +Handle the case where a flash device is mostly addressed using physical +line and supplemented by GPIOs. This way you can hook up say a 8MiB flash +to a 2MiB memory range and use the GPIOs to select a particular range. + + - compatible : "cfi-gpio-addr-flash" + - reg : Address range of the mtd chip that is memory mapped, this is, + on the previous example 2MiB. + - bank-width : Width (in bytes) of the bank. Equal to the + device width times the number of interleaved chips. + - probe-type : (optional) "cfi_probe", "jedec_probe". How the mtd chip + is going to be probed. If omitted, assumed to be equal to "cfi_probe". + - #address-cells, #size-cells : Must be present if the device has + sub-nodes representing partitions (see below). In this case + both #address-cells and #size-cells must be equal to 1. + +The device tree may optionally contain sub-nodes describing partitions of the +address space. See partition.txt for more detail. + +Example: + + cfi_flash_0: cfi_flash { + #address-cells = <1>; + #size-cells = <1>; + compatible = "cfi-gpio-addr-flash"; + bank-width = <2>; + reg = < 0x00300000 0x00200000 >; + gpios = <&gpio_0 3 0>, <&gpio_0 4 0>; + partition@0 { + reg = < 0x0 0x200000 >; + label = "Golden Bitstream"; + }; + partition@200000 { + reg = < 0x200000 0x200000 >; + label = "User Bitstream"; + }; + partition@400000 { + reg = < 0x400000 0x200000 >; + label = "V4L Controls"; + }; + partition@600000 { + reg = < 0x600000 0x200000 >; + label = "Production Data"; + }; + } ;
Add documentation for gpio-addr-flash. This binding allow creating flash devices that are paged using GPIOs. Cc: devicetree@vger.kernel.org Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com> --- .../bindings/mtd/gpio-addr-flash.txt | 46 +++++++++++++++++++ 1 file changed, 46 insertions(+) create mode 100644 Documentation/devicetree/bindings/mtd/gpio-addr-flash.txt