On Fri, 23 Jun 2023 13:42:56 +0200, Steffen Trumtrar wrote:
> FPGA programming on ZynqMP is done by the PMU. The SoC just hands a
> file to the PMU and lets it load this file to the FPGA.
>
> The bitstream that is sent to the FPGA consists of two headers, the
> optional struct bs_header and a binary-header. See comment in driver:
>
> (...)
> * Bitstream can be provided with an optinal header (`struct bs_header`).
> * The true bitstream starts with the binary-header composed of 21 words:
> (...)
>
> The PMUFW v1.0 had a feature for taking the bitstream only, skipping
> the header, or including the binary-header and only skipping the
> optional header. This is controlled via the BIT_ONLY_BIN flag. When
> the flag is set, the complete header should be skipped.
>
> The current implementation sets the flag *and* sends the binary-header
> to the PMU:
>
> header_length = get_header_length(mgr->buf, mgr->size);
> (...)
> body = (u32 *)&mgr->buf[header_length];
>
> get_header_length searches for the first DUMMY_WORD, i.e. the beginning
> of the binary header. Then we set body to this offset, skipping the
> optional header.
>
> The flag is always set to ZYNQMP_FPGA_BIT_ONLY_BIN, which is then obviously
> incorrect. It seems like the PMUFW v1.0 was capable of still handling this
> although the flag was set.
>
> The newer PMUFW v1.1 doesn't support this and expects the flag to be
> unset and getting handed binary-header+bitstream. This is the same as
> the linux kernel handles bitstream loading on the ZynqMP. There the flag
> is also always unset.
>
> As this wasn't correct in the first place (although it most likely still
> worked depending on PMUFW and its configuration), we won't break anything
> when we just set the flag to zero as the PMUFW v1.1 expects it.
>
> TLDR: set fpga_load flags to zero to fix firmwareloading with newer
> PMUFW versions.
>
> Signed-off-by: Steffen Trumtrar <s.trumtrar@xxxxxxxxxxxxxx>
Reviewed-by: Michael Tretter <m.tretter@xxxxxxxxxxxxxx>
> ---
> drivers/firmware/zynqmp-fpga.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/firmware/zynqmp-fpga.c b/drivers/firmware/zynqmp-fpga.c
> index 9c160e9098..1a9a5c1b2c 100644
> --- a/drivers/firmware/zynqmp-fpga.c
> +++ b/drivers/firmware/zynqmp-fpga.c
> @@ -206,7 +206,7 @@ static int fpgamgr_program_finish(struct firmware_handler *fh)
> enum xilinx_byte_order byte_order;
> dma_addr_t addr;
> int status = 0;
> - u8 flags = ZYNQMP_FPGA_BIT_ONLY_BIN;
> + u8 flags = 0;
>
> if (!mgr->buf) {
> status = -ENOBUFS;
> --
> 2.41.0
>
>
