It is not always whole FPGA image buffer meant to be written to the
device.
Add bitstream_start and bitstream_size to the fpga_image_info struct and
adjust fpga_mgr_write() callers with respect to them.
If initial_header_size is not known beforehand, pass whole buffer to low
level driver's write_init() so it could setup info->bitstream_start and
info->bitstream_size regardless.
Signed-off-by: Ivan Bornyakov <i.bornyakov@xxxxxxxxxxx>
---
drivers/fpga/fpga-mgr.c | 48 +++++++++++++++++++++++++++++------
include/linux/fpga/fpga-mgr.h | 5 ++++
2 files changed, 45 insertions(+), 8 deletions(-)
diff --git a/drivers/fpga/fpga-mgr.c b/drivers/fpga/fpga-mgr.c
index d49a9ce34568..c64e60e23a71 100644
--- a/drivers/fpga/fpga-mgr.c
+++ b/drivers/fpga/fpga-mgr.c
@@ -139,7 +139,8 @@ EXPORT_SYMBOL_GPL(fpga_image_info_free);
* Call the low level driver's write_init function. This will do the
* device-specific things to get the FPGA into the state where it is ready to
* receive an FPGA image. The low level driver only gets to see the first
- * initial_header_size bytes in the buffer.
+ * initial_header_size bytes in the buffer, if initial_header_size is set.
+ * Otherwise, the whole buffer will be passed.
*/
static int fpga_mgr_write_init_buf(struct fpga_manager *mgr,
struct fpga_image_info *info,
@@ -148,12 +149,10 @@ static int fpga_mgr_write_init_buf(struct fpga_manager *mgr,
int ret;
mgr->state = FPGA_MGR_STATE_WRITE_INIT;
- if (!mgr->mops->initial_header_size)
- ret = fpga_mgr_write_init(mgr, info, NULL, 0);
- else
- ret = fpga_mgr_write_init(
- mgr, info, buf, min(mgr->mops->initial_header_size, count));
+ if (mgr->mops->initial_header_size)
+ count = min(mgr->mops->initial_header_size, count);
+ ret = fpga_mgr_write_init(mgr, info, buf, count);
if (ret) {
dev_err(&mgr->dev, "Error preparing FPGA for writing\n");
mgr->state = FPGA_MGR_STATE_WRITE_INIT_ERR;
@@ -235,13 +234,33 @@ static int fpga_mgr_buf_load_sg(struct fpga_manager *mgr,
if (mgr->mops->write_sg) {
ret = fpga_mgr_write_sg(mgr, sgt);
} else {
+ size_t offset, count, length, bitstream_size;
struct sg_mapping_iter miter;
+ offset = info->bitstream_start;
+ bitstream_size = info->bitstream_size;
+ count = 0;
+
sg_miter_start(&miter, sgt->sgl, sgt->nents, SG_MITER_FROM_SG);
while (sg_miter_next(&miter)) {
- ret = fpga_mgr_write(mgr, miter.addr, miter.length);
- if (ret)
+ if (offset >= miter.length) {
+ offset -= miter.length;
+ continue;
+ }
+
+ if (bitstream_size)
+ length = min(miter.length - offset,
+ bitstream_size - count);
+ else
+ length = miter.length - offset;
+
+ count += length;
+
+ ret = fpga_mgr_write(mgr, miter.addr + offset, length);
+ if (ret || count == bitstream_size)
break;
+
+ offset = 0;
}
sg_miter_stop(&miter);
}
@@ -265,6 +284,19 @@ static int fpga_mgr_buf_load_mapped(struct fpga_manager *mgr,
if (ret)
return ret;
+ if (info->bitstream_start > count) {
+ dev_err(&mgr->dev,
+ "Bitstream start %zd outruns firmware image %zd\n",
+ info->bitstream_start, count);
+ return -EINVAL;
+ }
+
+ if (info->bitstream_size)
+ count = min(info->bitstream_start + info->bitstream_size, count);
+
+ buf += info->bitstream_start;
+ count -= info->bitstream_start;
+
/*
* Write the FPGA image to the FPGA.
*/
diff --git a/include/linux/fpga/fpga-mgr.h b/include/linux/fpga/fpga-mgr.h
index 0f9468771bb9..32464fd10cca 100644
--- a/include/linux/fpga/fpga-mgr.h
+++ b/include/linux/fpga/fpga-mgr.h
@@ -85,6 +85,9 @@ enum fpga_mgr_states {
* @sgt: scatter/gather table containing FPGA image
* @buf: contiguous buffer containing FPGA image
* @count: size of buf
+ * @bitstream_start: offset in image buffer where bitstream data starts
+ * @bitstream_size: size of bitstream.
+ * If 0, (count - bitstream_start) will be used.
* @region_id: id of target region
* @dev: device that owns this
* @overlay: Device Tree overlay
@@ -98,6 +101,8 @@ struct fpga_image_info {
struct sg_table *sgt;
const char *buf;
size_t count;
+ size_t bitstream_start;
+ size_t bitstream_size;
int region_id;
struct device *dev;
#ifdef CONFIG_OF
--
2.25.1
