On Mon, Dec 30, 2013 at 4:18 PM, Laurent Pinchart
[off-list ref] wrote:

quoted

There are subtle register differences between RSPI on SH7757 and RZ/A1H,
cfr. what rspi_parse_platform_data() does when no platform_data is
passed[*]. RSPI on RZ/A1H seems to be an evolutionary step from RSPI on SH
towards QSPI on RCar Gen2 (but without Dual/Quad).

[*] setup-sh7757.c doesn't pass platform data, although the rspi driver and
its platform data has support for DMA on SH7757, which is not used by
setup-sh7757.c nor any other in-tree platform.

The only important difference I can see (beside the hardcoded 16-bit width
which could be selected as the default) is that the SSH7757 RSPI has no SPL
bits in SPDCR. I don't have access tot he SH7757 datasheet, could you please
confirm that ?

SH7757 has RSPI Control Register 2 and the TX only mode flag, while
RSPI-RZ (and QSPI) haven't.
The number of interrupts also differ, but that's easily handled via
the interrupts
property.

BTW, I also don't have the SH7757 datasheet (will check), so my knowledge
there is purely based on the behavior of the code.

quoted

quoted

in my opinion is whether we want to use

compatible = "renesas,rspi-r7s72100", "renesas,rspi";

or

compatible = "renesas,rspi-r7s72100", "renesas,rspi-rz", "renesas,rspi";

So we end up with:

compatible = "renesas,sh7757", "renesas,rspi-sh" (SH legacy)
compatible = "renesas,rspi-r7s72100", "renesas,rspi-rz" (Genmai)
compatible = "renesas,rspi-r8a7790", "renesas,qspi" (Lager)
compatible = "renesas,rspi-r8a7791", "renesas,qspi" (Koelsch)

Don't you mean "renesas,qspi-r8a7790" and "renesas,qspi-r8a7791" ?

Oops, yes, sorry about that.

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds