[PATCH] crypto: octeontx2: disable DMA black hole on an DMA fault

[Shijith Thotton <sthotton@xxxxxxxxxxx>]

From: Srujana Challa <schalla@xxxxxxxxxxx>

When CPT_AF_DIAG[FLT_DIS] = 0 and a CPT engine access to
LLC/DRAM encounters a fault/poison, a rare case may result
in unpredictable data being delivered to a CPT engine.
So, this patch adds code to set FLT_DIS as a workaround.

Signed-off-by: Srujana Challa <schalla@xxxxxxxxxxx>
Signed-off-by: Shijith Thotton <sthotton@xxxxxxxxxxx>
---
 drivers/crypto/marvell/octeontx2/otx2_cptpf_ucode.c | 13 +++++++++++++
 drivers/net/ethernet/marvell/octeontx2/af/rvu_cpt.c |  1 +
 2 files changed, 14 insertions(+)

diff --git a/drivers/crypto/marvell/octeontx2/otx2_cptpf_ucode.c b/drivers/crypto/marvell/octeontx2/otx2_cptpf_ucode.c
index 4c8ebdf671ca..e0b29cf504b9 100644
--- a/drivers/crypto/marvell/octeontx2/otx2_cptpf_ucode.c
+++ b/drivers/crypto/marvell/octeontx2/otx2_cptpf_ucode.c
@@ -1111,6 +1111,7 @@ int otx2_cpt_create_eng_grps(struct otx2_cptpf_dev *cptpf,
 	struct otx2_cpt_engines engs[OTX2_CPT_MAX_ETYPES_PER_GRP] = { {0} };
 	struct pci_dev *pdev = cptpf->pdev;
 	struct fw_info_t fw_info;
+	u64 reg_val;
 	int ret = 0;
 
 	mutex_lock(&eng_grps->lock);
@@ -1203,6 +1204,18 @@ int otx2_cpt_create_eng_grps(struct otx2_cptpf_dev *cptpf,
 	 */
 	otx2_cpt_write_af_reg(&cptpf->afpf_mbox, pdev, CPT_AF_CTX_FLUSH_TIMER,
 			      CTX_FLUSH_TIMER_CNT, BLKADDR_CPT0);
+
+	/*
+	 * Set CPT_AF_DIAG[FLT_DIS], as a workaround for HW errata, when
+	 * CPT_AF_DIAG[FLT_DIS] = 0 and a CPT engine access to LLC/DRAM
+	 * encounters a fault/poison, a rare case may result in
+	 * unpredictable data being delivered to a CPT engine.
+	 */
+	otx2_cpt_read_af_reg(&cptpf->afpf_mbox, pdev, CPT_AF_DIAG, &reg_val,
+			     BLKADDR_CPT0);
+	otx2_cpt_write_af_reg(&cptpf->afpf_mbox, pdev, CPT_AF_DIAG,
+			      reg_val | BIT_ULL(24), BLKADDR_CPT0);
+
 	mutex_unlock(&eng_grps->lock);
 	return 0;
 
diff --git a/drivers/net/ethernet/marvell/octeontx2/af/rvu_cpt.c b/drivers/net/ethernet/marvell/octeontx2/af/rvu_cpt.c
index 45357deecabb..1f7c971e6757 100644
--- a/drivers/net/ethernet/marvell/octeontx2/af/rvu_cpt.c
+++ b/drivers/net/ethernet/marvell/octeontx2/af/rvu_cpt.c
@@ -606,6 +606,7 @@ static bool is_valid_offset(struct rvu *rvu, struct cpt_rd_wr_reg_msg *req)
 	} else if (!(req->hdr.pcifunc & RVU_PFVF_FUNC_MASK)) {
 		/* Registers that can be accessed from PF */
 		switch (offset) {
+		case CPT_AF_DIAG:
 		case CPT_AF_CTL:
 		case CPT_AF_PF_FUNC:
 		case CPT_AF_BLK_RST:
-- 
2.25.1