Re: [PATCH v5 0/2] Lattice ECP5 FPGA manager

From: Ivan Bornyakov
Date: Thu Jul 21 2022 - 04:55:12 EST


On Thu, Jul 21, 2022 at 03:44:31PM +0800, Xu Yilun wrote:
> On Tue, Jul 19, 2022 at 02:23:33PM +0300, Ivan Bornyakov wrote:
> > Add support to the FPGA manager for programming Lattice ECP5 FPGA over
> > slave SPI interface with .bit formatted uncompressed bitstream image.
>
> I didn't have time to looking into the patches yet, but I have some quick
> question.
>
> Where is the bitstream data writing to? To the FPGA active region or the
> backup nvmem like flash?

Bitstream is written to FPGA's volatile SRAM configuration memory.

>
> After reconfiguration, how to re-enumerate the hardware devices in the
> newly programmed FPGA region?
>

I personally describe FPGA-based devices statically in DT overlay within
fpga-region. Of course this approach is error prone to mismatch between
firmware and devices described in DT overlay...

> Thanks,
> Yilun
>
> >
> > ChangeLog:
> > v1 -> v2:
> > * remove "spi" from compatible string
> > * reword description in dt-bindings doc
> > * add reference to spi-peripheral-props.yaml in dt-binding doc
> > * fix DTS example in dt-bindings doc: 4-spaces indentations, no
> > undersores in node names.
> > v2 -> v3:
> > * fix typo "##size-cells" -> "#size-cells" in dt-bindings example
> > v3 -> v4:
> > * dt-bindings: reword description
> > * dt-bindings: revert props order
> > v4 -> v5:
> > * dt-bindings: remove trailing dot from title
> > * dt-bindings: reword description to avoid driver reference
> > * dt-bindings: add "Reviewed-by: Krzysztof Kozlowski" tag
> >
> > Ivan Bornyakov (2):
> > fpga: ecp5-spi: add Lattice ECP5 FPGA manager
> > dt-bindings: fpga: add binding doc for ecp5-spi fpga mgr
> >
> > .../bindings/fpga/lattice,ecp5-fpga-mgr.yaml | 74 +++++
> > drivers/fpga/Kconfig | 7 +
> > drivers/fpga/Makefile | 1 +
> > drivers/fpga/ecp5-spi.c | 275 ++++++++++++++++++
> > 4 files changed, 357 insertions(+)
> > create mode 100644 Documentation/devicetree/bindings/fpga/lattice,ecp5-fpga-mgr.yaml
> > create mode 100644 drivers/fpga/ecp5-spi.c
> >
> > --
> > 2.37.1
> >