crypto: caampkc - workaround for erratum A-006899

The problem will occur only in T1040R1. A workaround
has been verified; set a Scatter Gather (SG) flag
on the Q or G Pointers on KPG, which will give
the PKHA unload time to complete. It's sufficient
to have the SG flag set for only one of these.

Change-Id: I5a403576c6e995110227872c84de7e74da0144c5
Signed-off-by: Tudor Ambarus <tudor.ambarus@freescale.com>
Reviewed-on: http://git.am.freescale.net:8181/36617
Tested-by: Review Code-CDREVIEW <CDREVIEW@freescale.com>
Reviewed-by: Horia Ioan Geanta Neag <horia.geanta@freescale.com>
Reviewed-by: Honghua Yin <Hong-Hua.Yin@freescale.com>

7 files changed, 60 insertions, 15 deletions

diff --git a/drivers/crypto/caam/caampkc.c b/drivers/crypto/caam/caampkc.c
index f98abfb..e9944a4 100644
--- a/drivers/crypto/caam/caampkc.c
+++ b/drivers/crypto/caam/caampkc.c
@@ -30,6 +30,12 @@ struct caam_pkc_context_s {
 	struct device *dev;
 };
 
+struct caam_pkc_alg {
+	struct list_head entry;
+	struct device *ctrldev;
+	struct crypto_alg crypto_alg;
+};
+
 static void rsa_unmap(struct device *dev,
 		      struct rsa_edesc *edesc, struct pkc_request *req)
 {
@@ -484,6 +490,10 @@ static int caam_keygen_edesc(struct pkc_request *req,
 {
 	struct crypto_pkc *tfm = crypto_pkc_reqtfm(req);
 	struct caam_pkc_context_s *ctxt = crypto_pkc_ctx(tfm);
+	struct crypto_alg *alg = crypto_pkc_tfm(tfm)->__crt_alg;
+	struct caam_pkc_alg *caam_alg =
+			container_of(alg, struct caam_pkc_alg, crypto_alg);
+	struct caam_drv_private *caam_priv = dev_get_drvdata(caam_alg->ctrldev);
 	struct device *dev = ctxt->dev;
 	struct keygen_req_s *key_req = &req->req_u.keygen;
 
@@ -491,6 +501,7 @@ static int caam_keygen_edesc(struct pkc_request *req,
 	edesc->n_len = key_req->r_len;
 	edesc->req_type = req->type;
 	edesc->curve_type = req->curve_type;
+	edesc->erratum_A_006899 = caam_priv->errata & SEC_ERRATUM_A_006899;
 
 	edesc->q_dma = dma_map_single(dev, key_req->q, key_req->q_len,
 					  DMA_TO_DEVICE);
@@ -513,6 +524,20 @@ static int caam_keygen_edesc(struct pkc_request *req,
 		goto g_map_fail;
 	}
 
+	if (edesc->erratum_A_006899) {
+		dma_to_sec4_sg_one(&(edesc->g_sg), edesc->g_dma,
+				   key_req->g_len, 0);
+		edesc->g_sg.len |= SEC4_SG_LEN_FIN;
+
+		edesc->g_sg_dma = dma_map_single(dev, &(edesc->g_sg),
+						 sizeof(struct sec4_sg_entry),
+						 DMA_TO_DEVICE);
+		if (dma_mapping_error(dev, edesc->g_sg_dma)) {
+			dev_err(dev, "unable to map S/G table\n");
+			goto g_sg_dma_fail;
+		}
+	}
+
 	edesc->key_dma = dma_map_single(dev, key_req->pub_key,
 					key_req->pub_key_len, DMA_FROM_DEVICE);
 	if (dma_mapping_error(dev, edesc->key_dma)) {
@@ -545,6 +570,10 @@ s_map_fail:
 	dma_unmap_single(dev, edesc->key_dma, key_req->pub_key_len,
 			 DMA_FROM_DEVICE);
 key_map_fail:
+	if (edesc->erratum_A_006899)
+		dma_unmap_single(dev, edesc->g_sg_dma, key_req->g_len,
+				 DMA_TO_DEVICE);
+g_sg_dma_fail:
 	dma_unmap_single(dev, edesc->g_dma, key_req->g_len, DMA_TO_DEVICE);
 g_map_fail:
 	dma_unmap_single(dev, edesc->r_dma, key_req->r_len, DMA_TO_DEVICE);
@@ -1324,12 +1353,6 @@ static struct caam_pkc_template driver_pkc[] = {
 	 }
 };
 
-struct caam_pkc_alg {
-	struct list_head entry;
-	struct device *ctrldev;
-	struct crypto_alg crypto_alg;
-};
-
 /* Per session pkc's driver context creation function */
 static int caam_pkc_cra_init(struct crypto_tfm *tfm)
 {
diff --git a/drivers/crypto/caam/ctrl.c b/drivers/crypto/caam/ctrl.c
index 7a22427..321deb0 100644
--- a/drivers/crypto/caam/ctrl.c
+++ b/drivers/crypto/caam/ctrl.c
@@ -480,6 +480,7 @@ static int caam_probe(struct platform_device *pdev)
 {
 	int ret, ring, rspec;
 	u64 caam_id;
+	u32 caam_id_ms;
 	struct device *dev;
 	struct device_node *nprop, *np;
 	struct caam_ctrl __iomem *ctrl;
@@ -660,7 +661,12 @@ static int caam_probe(struct platform_device *pdev)
 	/* NOTE: RTIC detection ought to go here, around Si time */
 
 	ctrlpriv->era = caam_get_era();
-	caam_id = (u64)rd_reg32(&ctrl->perfmon.caam_id_ms) << 32 |
+
+	caam_id_ms = rd_reg32(&ctrl->perfmon.caam_id_ms);
+	if (caam_id_ms == SEC_ID_MS_T1040)
+		ctrlpriv->errata |= SEC_ERRATUM_A_006899;
+
+	caam_id = (u64)caam_id_ms << 32 |
 		  (u64)rd_reg32(&ctrl->perfmon.caam_id_ls);
 
 	/* Report "alive" for developer to see */
diff --git a/drivers/crypto/caam/intern.h b/drivers/crypto/caam/intern.h
index 43596fe..9faf832 100644
--- a/drivers/crypto/caam/intern.h
+++ b/drivers/crypto/caam/intern.h
@@ -95,6 +95,11 @@ struct caam_drv_private {
 	struct list_head pkc_list;
 
 	int era;		/* SEC Era */
+
+#define SEC_ERRATUM_A_006899 0x01
+	/* SEC errata bitmask */
+	u32 errata;
+
 	int virt_en;		/* Virtualization enabled in CAAM */
 
 #define	RNG4_MAX_HANDLES 2
diff --git a/drivers/crypto/caam/pkc_desc.c b/drivers/crypto/caam/pkc_desc.c
index 5bcf5d3..2e81519 100644
--- a/drivers/crypto/caam/pkc_desc.c
+++ b/drivers/crypto/caam/pkc_desc.c
@@ -271,10 +271,15 @@ void *caam_keygen_desc(struct dsa_edesc_s *edesc)
 			      (start_idx << HDR_START_IDX_SHIFT) |
 			      (start_idx & HDR_DESCLEN_MASK) | HDR_ONE);
 		ecc_desc->sgf_ln = (edesc->l_len << DSA_PDB_L_SHIFT) |
-			((edesc->n_len & DSA_PDB_N_MASK));
+				   (edesc->n_len & DSA_PDB_N_MASK);
+		if (edesc->erratum_A_006899) {
+			ecc_desc->sgf_ln |= DSA_PDB_SGF_G;
+			ecc_desc->g_dma = edesc->g_sg_dma;
+		} else {
+			ecc_desc->g_dma = edesc->g_dma;
+		}
 		ecc_desc->q_dma = edesc->q_dma;
 		ecc_desc->r_dma = edesc->r_dma;
-		ecc_desc->g_dma = edesc->g_dma;
 		ecc_desc->s_dma = edesc->s_dma;
 		ecc_desc->w_dma = edesc->key_dma;
 		ecc_desc->ab_dma = edesc->ab_dma;
diff --git a/drivers/crypto/caam/pkc_desc.h b/drivers/crypto/caam/pkc_desc.h
index 03013c2..e859e40 100644
--- a/drivers/crypto/caam/pkc_desc.h
+++ b/drivers/crypto/caam/pkc_desc.h
@@ -20,6 +20,7 @@
 #include "desc_constr.h"
 #include "jr.h"
 #include "error.h"
+#include "sg_sw_sec4.h"
 #include <linux/crypto.h>
 #include "pdb.h"
 
@@ -187,8 +188,11 @@ struct dsa_edesc_s {
 	dma_addr_t d_dma;
 	dma_addr_t ab_dma;
 	dma_addr_t g_dma;
+	dma_addr_t g_sg_dma;
 	dma_addr_t tmp_dma;
 	uint8_t *tmp; /* Allocate locally for dsa_verify */
+	struct sec4_sg_entry g_sg;
+	bool erratum_A_006899;
 	u32 hw_desc[];
 };
 
diff --git a/drivers/crypto/caam/regs.h b/drivers/crypto/caam/regs.h
index 928cb53..72193f8 100644
--- a/drivers/crypto/caam/regs.h
+++ b/drivers/crypto/caam/regs.h
@@ -182,6 +182,8 @@ struct sec_vid {
 	u8 min_rev;
 };
 
+#define SEC_ID_MS_T1040		0x0A120400
+
 struct caam_perfmon {
 	/* Performance Monitor Registers			f00-f9f */
 	u64 req_dequeued;	/* PC_REQ_DEQ - Dequeued Requests	     */
diff --git a/drivers/crypto/caam/sg_sw_sec4.h b/drivers/crypto/caam/sg_sw_sec4.h
index eef6345..752134c 100644
--- a/drivers/crypto/caam/sg_sw_sec4.h
+++ b/drivers/crypto/caam/sg_sw_sec4.h
@@ -90,9 +90,9 @@ static inline int sg_count(struct scatterlist *sg_list, int nbytes,
 	return sg_nents;
 }
 
-static int dma_map_sg_chained(struct device *dev, struct scatterlist *sg,
-			      unsigned int nents, enum dma_data_direction dir,
-			      bool chained)
+static int __maybe_unused dma_map_sg_chained(struct device *dev,
+	struct scatterlist *sg, unsigned int nents, enum dma_data_direction dir,
+	bool chained)
 {
 	if (!sg || !nents)
 		return 0;
@@ -109,9 +109,9 @@ static int dma_map_sg_chained(struct device *dev, struct scatterlist *sg,
 	return nents;
 }
 
-static void dma_unmap_sg_chained(struct device *dev, struct scatterlist *sg,
-				unsigned int nents, enum dma_data_direction dir,
-				bool chained)
+static void __maybe_unused dma_unmap_sg_chained(struct device *dev,
+	struct scatterlist *sg, unsigned int nents, enum dma_data_direction dir,
+	bool chained)
 {
 	if (!sg || !nents)
 		return;