In my continuing saga of dev/tree driver development, I have a problem which
might be obvious to those who have more experience in such matters.
I'm a bit perplexed on the tree nodes for the localbus/simplebus nodes for my
FPGA. CS0 is reserved for booting (from NOR flash as required by our design),
CS1 is tied to an FPGA which will always be present. CS2 actually is tied to
both of two (optional) fpga's, which have been previously mapped by U-Boot
(BRn/ORn configuration). Should I specify a ranges command as follows? This
seems somehow wrong, to me, and I'm wondering if there is an alternative
representation which would work better in this case. If you recall, the
programming control lines are handled on the I2C bus, via a gpio controller.
In an ideal world, the optional FPE1 and FPE2 fpgas will have the identical
.bts stream, and should support the option to program both simultaneously, or
each individually, but I'm at a loss as how to best represent this in the tree.
localbus@ffe124000 {
compatible = "fsl,p4080-elbc", "fsl,elbc", "simple-bus";
reg = <0xf 0xfe124000 0 0x1000>;
interrupts = <25 2 0 0>;
interrupt-parent = <&mpic>;
#address-cells = <2>;
#size-cells = <1>;
/* Local bus region mappings */
ranges = <0 0 0xf 0xe8000000 0x08000000 /* CS0: Boot
flash */
1 0 0xf 0xd0000000 0x7fff /* CS1: FPGA0 -
LIM */
2 0 0xf 0xd1000000 0x7fff /* CS2: FPGA1 -
FPE1 */
2 0 0xf 0xd2000000 0x7fff >; /* CS2: FPGA2 -
FPE2 */
flash@0,0 {
compatible = "cfi-flash";
reg = <0 0 0x08000000>;
bank-width = <2>;
device-width = <2>;
#size-cells = <1>;
#address-cells = <1>;
partition@0 {
label = "rcw";
reg = <0x0 0x20000>;
read-only;
};
partition@40000 {
label = "saveenv";
reg = <0x40000 0x20000>;
};
partition@7000000 {
label = "fman-firmware";
reg = <0x7000000 0x20000>;
read-only;
};
partition@7f80000 {
label = "u-boot";
reg = <0x7f80000 0x80000>;
read-only;
};
};
lim: fpga@1, {
}
fpe1: fpga@2, {
}
fpe2: fpga@2, {
}
Again, any pointers here would be greatly appreciated ...
Cheers,
Rob Sciuk
_______________________________________________
Linuxppc-dev mailing list
Linuxppc-dev@lists.ozlabs.org
https://lists.ozlabs.org/listinfo/linuxppc-dev
