On Fri, Jun 10, 2022 at 03:43:11PM +0800, Xu Yilun wrote: > On Thu, Jun 09, 2022 at 06:47:49PM +0300, Ivan Bornyakov wrote: > > At the moment FPGA manager core loads to the device entire image > > provided to fpga_mgr_load(). But it is not always whole FPGA image > > buffer meant to be written to the device. In particular, .dat formatted > > image for Microchip MPF contains meta info in the header that is not > > meant to be written to the device. This is issue for those low level > > drivers that loads data to the device with write() fpga_manager_ops > > callback, since write() can be called in iterator over scatter-gather > > table, not only linear image buffer. On the other hand, write_sg() > > callback is provided with whole image in scatter-gather form and can > > decide itself which part should be sent to the device. > > > > Add header_size and data_size to the fpga_image_info struct and adjust > > fpga_mgr_write() callers with respect to them. > > > > * info->header_size indicates part at the beginning of image buffer > > that is *not* meant to be written to the device. It is optional and > > can be 0. > > > > * info->data_size is the size of actual bitstream data that *is* meant > > to be written to the device, starting at info->header_size from the > > beginning of image buffer. It is also optional and can be 0, which > > means bitstream data is up to the end of image buffer. > > > > Also add parse_header() callback to fpga_manager_ops, which purpose is > > to set info->header_size and info->data_size. At least > > initial_header_size bytes of image buffer will be passed into > > parse_header() first time. If it is not enough, parse_header() should > > set desired size into info->header_size and return -EAGAIN, then it will > > be called again with greater part of image buffer on the input. > > > > Signed-off-by: Ivan Bornyakov <i.bornyakov@xxxxxxxxxxx> > > --- > > drivers/fpga/fpga-mgr.c | 243 +++++++++++++++++++++++++++++----- > > include/linux/fpga/fpga-mgr.h | 17 ++- > > 2 files changed, 229 insertions(+), 31 deletions(-) > > > > diff --git a/drivers/fpga/fpga-mgr.c b/drivers/fpga/fpga-mgr.c > > index 08dc85fcd511..0854fbc8f11e 100644 > > --- a/drivers/fpga/fpga-mgr.c > > +++ b/drivers/fpga/fpga-mgr.c > > Should we check in fpga_mgr_create, that initial_header_size must not be > 0 if parse_header() is defined. If we pass no data to parse_header(), > does it make any sense? Sorry, there is no fpga_mgr_create now, should be fpga_mgr_register_full Thanks, Yilun
