On Thu, May 26, 2022 at 09:13:43PM +0300, Ivan Bornyakov wrote:
> Add support to the FPGA manager for programming Microchip Polarfire
> FPGAs over slave SPI interface with .dat formatted bitsream image.
>From previous mail thread, there are still some hardware operations yet
to be clarified, so I may need a Reviewed-by from Conor.Dooley@xxxxxxxxxxxxx.
[...]
> +static int mpf_ops_parse_header(struct fpga_manager *mgr,
> + struct fpga_image_info *info,
> + const char *buf, size_t count)
> +{
> + size_t component_size_byte_num, component_size_byte_off,
> + components_size_start, bitstream_start, i,
> + block_id_offset, block_start_offset;
> + u8 header_size, blocks_num, block_id;
I think component_size_byte_num, component_size_byte_off, i should be size_t
are all simple numbers irrelated to data size, so maybe u32 is just good.
Thanks,
Yilun
> + u32 block_start, component_size;
> + u16 components_num;
> +
> + if (!buf) {
> + dev_err(&mgr->dev, "Image buffer is not provided\n");
> + return -EINVAL;
> + }
> +
> + header_size = *(buf + MPF_HEADER_SIZE_OFFSET);
> + if (header_size > count) {
> + info->header_size = header_size;
> + return -EAGAIN;
> + }
> +
> + /*
> + * Go through look-up table to find out where actual bitstream starts
> + * and where sizes of components of the bitstream lies.
> + */
> + blocks_num = *(buf + header_size - 1);
> + block_id_offset = header_size + MPF_LOOKUP_TABLE_BLOCK_ID_OFFSET;
> + block_start_offset = header_size + MPF_LOOKUP_TABLE_BLOCK_START_OFFSET;
> +
> + header_size += blocks_num * MPF_LOOKUP_TABLE_RECORD_SIZE;
> + if (header_size > count) {
> + info->header_size = header_size;
> + return -EAGAIN;
> + }
> +
> + components_size_start = 0;
> + bitstream_start = 0;
> +
> + while (blocks_num--) {
> + block_id = *(buf + block_id_offset);
> + block_start = get_unaligned_le32(buf + block_start_offset);
> +
> + switch (block_id) {
> + case MPF_BITSTREAM_ID:
> + info->header_size = bitstream_start = block_start;
> + if (block_start > count)
> + return -EAGAIN;
> +
> + break;
> + case MPF_COMPONENTS_SIZE_ID:
> + components_size_start = block_start;
> + break;
> + default:
> + break;
> + }
> +
> + if (bitstream_start && components_size_start)
> + break;
> +
> + block_id_offset += MPF_LOOKUP_TABLE_RECORD_SIZE;
> + block_start_offset += MPF_LOOKUP_TABLE_RECORD_SIZE;
> + }
> +
> + if (!bitstream_start || !components_size_start) {
> + dev_err(&mgr->dev, "Failed to parse header look-up table\n");
> + return -EFAULT;
> + }
> +
> + /*
> + * Parse bitstream size.
> + * Sizes of components of the bitstream are 22-bits long placed next
> + * to each other. Image header should be extended by now up to where
> + * actual bitstream starts, so no need for overflow check anymore.
> + */
> + components_num = get_unaligned_le16(buf + MPF_DATA_SIZE_OFFSET);
> +
> + for (i = 0; i < components_num; i++) {
> + component_size_byte_num =
> + (i * MPF_BITS_PER_COMPONENT_SIZE) / BITS_PER_BYTE;
> + component_size_byte_off =
> + (i * MPF_BITS_PER_COMPONENT_SIZE) % BITS_PER_BYTE;
> +
> + component_size = get_unaligned_le32(buf +
> + components_size_start +
> + component_size_byte_num);
> + component_size >>= component_size_byte_off;
> + component_size &= GENMASK(MPF_BITS_PER_COMPONENT_SIZE - 1, 0);
> +
> + info->data_size += component_size * MPF_SPI_FRAME_SIZE;
> + }
> +
> + return 0;
> +}
