[PATCH v20 14/14] crypto: qce - Communicate the base physical address to the dmaengine

From: Bartosz Golaszewski

Date: Mon Jun 29 2026 - 06:08:42 EST


In order to communicate to the BAM DMA engine which address should be
used as a scratchpad for dummy writes related to BAM pipe locking,
fill out and attach the provided metadata struct to the descriptor.

Reviewed-by: Manivannan Sadhasivam <mani@xxxxxxxxxx>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@xxxxxxxxxxxxxxxx>
---
drivers/crypto/qce/dma.c | 13 ++++++++++++-
1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/drivers/crypto/qce/dma.c b/drivers/crypto/qce/dma.c
index 1b43c56503334154be4b8000e5a9330b2005cb64..6410f8dc5bcf517223c768a3e8f87af245076c84 100644
--- a/drivers/crypto/qce/dma.c
+++ b/drivers/crypto/qce/dma.c
@@ -11,6 +11,7 @@

#include "core.h"
#include "dma.h"
+#include "regs-v5.h"

#define QCE_IGNORE_BUF_SZ (2 * QCE_BAM_BURST_SIZE)
#define QCE_BAM_CMD_SGL_SIZE 128
@@ -41,6 +42,10 @@ void qce_clear_bam_transaction(struct qce_device *qce)

int qce_submit_cmd_desc(struct qce_device *qce)
{
+ struct bam_desc_metadata meta = {
+ .scratchpad_addr = qce->base_phys + REG_VERSION,
+ .direction = DMA_MEM_TO_DEV,
+ };
struct qce_desc_info *qce_desc = qce->dma.bam_txn->desc;
struct qce_bam_transaction *bam_txn = qce->dma.bam_txn;
struct dma_async_tx_descriptor *dma_desc;
@@ -60,15 +65,21 @@ int qce_submit_cmd_desc(struct qce_device *qce)
goto err_unmap_sg;
}

+ ret = dmaengine_desc_attach_metadata(dma_desc, &meta, sizeof(meta));
+ if (ret)
+ goto err_free_desc;
+
qce_desc->dma_desc = dma_desc;
cookie = dmaengine_submit(qce_desc->dma_desc);

ret = dma_submit_error(cookie);
if (ret)
- goto err_unmap_sg;
+ goto err_free_desc;

return 0;

+err_free_desc:
+ dmaengine_desc_free(dma_desc);
err_unmap_sg:
dma_unmap_sg(qce->dev, bam_txn->wr_sgl, bam_txn->wr_sgl_cnt, DMA_TO_DEVICE);
return ret;

--
2.47.3