Re: [RFC 0/2] Add streaming API for firmware and FPGA manager

From: matthew . gerlach
Date: Fri Mar 10 2017 - 12:12:19 EST

On Thu, 9 Mar 2017, wrote:

From: Yi Li <>

Hi Yi,

This functionality is extremely helpful. I am working with a
firmware image of about 90 MBs, and even using scatter-gather instead of a continguous piece of memory is a lot of memory.

Matthew Gerlach

As the FPGA hardware advances, the firmware image size grows (hundres
of MBs or more). It could be an issue for kernel to allocate a big
buffer to load the whole firmware file.
Here is an attempt to read the firmware file into a small buffer and
program the FPGA in a loop (or so call the streaming mode). It should not
be a performance hit for FPGA programing since the majority of time
spend is with the FPGA CvP/PR-IP interface.

pseudo code in fpga manager:
while (size > 0) {
ret = stream_firmware(&fw, image_name, dev, offset, streamsize);
ret = mgr->mops->write(mgr, fw->data, fw->size);
offset += fw->size;
size -= fw->size;


Yi Li (2):
firmware class: Add stream_firmware API.
fpga manager: Add fpga_mgr_firmware_stream API

drivers/base/firmware_class.c | 128 ++++++++++++++++++++++++++++++++++++++++++
drivers/fpga/fpga-mgr.c | 77 +++++++++++++++++++++++++
include/linux/firmware.h | 2 +
include/linux/fpga/fpga-mgr.h | 4 ++
4 files changed, 211 insertions(+)


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