4 files changed, 34 insertions, 26 deletions

diff --git a/drivers/crypto/mediatek/mtk-aes.c b/drivers/crypto/mediatek/mtk-aes.c
index b57b68f2ac93..21f3e594804b 100644
--- a/drivers/crypto/mediatek/mtk-aes.c
+++ b/drivers/crypto/mediatek/mtk-aes.c
@@ -262,7 +262,7 @@ static int mtk_aes_xmit(struct mtk_cryp *cryp, struct mtk_aes_rec *aes)
 
         /* Write command descriptors */
         for (nents = 0; nents < slen; ++nents, ssg = sg_next(ssg)) {
-                cmd = ring->cmd_base + ring->cmd_pos;
+                cmd = ring->cmd_next;
                 cmd->hdr = MTK_DESC_BUF_LEN(ssg->length);
                 cmd->buf = cpu_to_le32(sg_dma_address(ssg));
 
@@ -274,22 +274,24 @@ static int mtk_aes_xmit(struct mtk_cryp *cryp, struct mtk_aes_rec *aes)
                         cmd->tfm = cpu_to_le32(aes->ctx->tfm_dma);
                 }
 
-                if (++ring->cmd_pos == MTK_DESC_NUM)
-                        ring->cmd_pos = 0;
+                /* Shift ring buffer and check boundary */
+                if (++ring->cmd_next == ring->cmd_base + MTK_DESC_NUM)
+                        ring->cmd_next = ring->cmd_base;
         }
         cmd->hdr |= MTK_DESC_LAST;
 
         /* Prepare result descriptors */
         for (nents = 0; nents < dlen; ++nents, dsg = sg_next(dsg)) {
-                res = ring->res_base + ring->res_pos;
+                res = ring->res_next;
                 res->hdr = MTK_DESC_BUF_LEN(dsg->length);
                 res->buf = cpu_to_le32(sg_dma_address(dsg));
 
                 if (nents == 0)
                         res->hdr |= MTK_DESC_FIRST;
 
-                if (++ring->res_pos == MTK_DESC_NUM)
-                        ring->res_pos = 0;
+                /* Shift ring buffer and check boundary */
+                if (++ring->res_next == ring->res_base + MTK_DESC_NUM)
+                        ring->res_next = ring->res_base;
         }
         res->hdr |= MTK_DESC_LAST;
 
diff --git a/drivers/crypto/mediatek/mtk-platform.c b/drivers/crypto/mediatek/mtk-platform.c
index 50de335ed332..b6ecc288b540 100644
--- a/drivers/crypto/mediatek/mtk-platform.c
+++ b/drivers/crypto/mediatek/mtk-platform.c
@@ -465,6 +465,9 @@ static int mtk_desc_ring_alloc(struct mtk_cryp *cryp)
                                            GFP_KERNEL);
                 if (!ring[i]->res_base)
                         goto err_cleanup;
+
+                ring[i]->cmd_next = ring[i]->cmd_base;
+                ring[i]->res_next = ring[i]->res_base;
         }
         return 0;
 
diff --git a/drivers/crypto/mediatek/mtk-platform.h b/drivers/crypto/mediatek/mtk-platform.h
index 78ce54e136c5..218e30d1828a 100644
--- a/drivers/crypto/mediatek/mtk-platform.h
+++ b/drivers/crypto/mediatek/mtk-platform.h
@@ -84,11 +84,11 @@ struct mtk_desc {
 /**
  * struct mtk_ring - Descriptor ring
  * @cmd_base:   pointer to command descriptor ring base
+ * @cmd_next:   pointer to the next command descriptor
  * @cmd_dma:    DMA address of command descriptor ring
- * @cmd_pos:    current position in the command descriptor ring
  * @res_base:   pointer to result descriptor ring base
+ * @res_next:   pointer to the next result descriptor
  * @res_dma:    DMA address of result descriptor ring
- * @res_pos:    current position in the result descriptor ring
  *
  * A descriptor ring is a circular buffer that is used to manage
  * one or more descriptors. There are two type of descriptor rings;
@@ -96,11 +96,11 @@ struct mtk_desc {
  */
 struct mtk_ring {
         struct mtk_desc *cmd_base;
+        struct mtk_desc *cmd_next;
         dma_addr_t cmd_dma;
-        u32 cmd_pos;
         struct mtk_desc *res_base;
+        struct mtk_desc *res_next;
         dma_addr_t res_dma;
-        u32 res_pos;
 };
 
 /**
diff --git a/drivers/crypto/mediatek/mtk-sha.c b/drivers/crypto/mediatek/mtk-sha.c
index ef6fb201f70d..0884d6243cbc 100644
--- a/drivers/crypto/mediatek/mtk-sha.c
+++ b/drivers/crypto/mediatek/mtk-sha.c
@@ -152,6 +152,21 @@ static inline void mtk_sha_write(struct mtk_cryp *cryp,
         writel_relaxed(value, cryp->base + offset);
 }
 
+static inline void mtk_sha_ring_shift(struct mtk_ring *ring,
+                                      struct mtk_desc **cmd_curr,
+                                      struct mtk_desc **res_curr,
+                                      int *count)
+{
+        *cmd_curr = ring->cmd_next++;
+        *res_curr = ring->res_next++;
+        (*count)++;
+
+        if (ring->cmd_next == ring->cmd_base + MTK_DESC_NUM) {
+                ring->cmd_next = ring->cmd_base;
+                ring->res_next = ring->res_base;
+        }
+}
+
 static struct mtk_cryp *mtk_sha_find_dev(struct mtk_sha_ctx *tctx)
 {
         struct mtk_cryp *cryp = NULL;
@@ -426,8 +441,7 @@ static int mtk_sha_xmit(struct mtk_cryp *cryp, struct mtk_sha_rec *sha,
 {
         struct mtk_sha_reqctx *ctx = ahash_request_ctx(sha->req);
         struct mtk_ring *ring = cryp->ring[sha->id];
-        struct mtk_desc *cmd = ring->cmd_base + ring->cmd_pos;
-        struct mtk_desc *res = ring->res_base + ring->res_pos;
+        struct mtk_desc *cmd, *res;
         int err, count = 0;
 
         err = mtk_sha_info_update(cryp, sha, len1, len2);
@@ -435,6 +449,8 @@ static int mtk_sha_xmit(struct mtk_cryp *cryp, struct mtk_sha_rec *sha,
                 return err;
 
         /* Fill in the command/result descriptors */
+        mtk_sha_ring_shift(ring, &cmd, &res, &count);
+
         res->hdr = MTK_DESC_FIRST | MTK_DESC_BUF_LEN(len1);
         cmd->hdr = MTK_DESC_FIRST | MTK_DESC_BUF_LEN(len1) |
                    MTK_DESC_CT_LEN(ctx->ct_size);
@@ -443,25 +459,12 @@ static int mtk_sha_xmit(struct mtk_cryp *cryp, struct mtk_sha_rec *sha,
         cmd->ct_hdr = ctx->ct_hdr;
         cmd->tfm = cpu_to_le32(ctx->tfm_dma);
 
-        if (++ring->cmd_pos == MTK_DESC_NUM)
-                ring->cmd_pos = 0;
-
-        ring->res_pos = ring->cmd_pos;
-        count++;
-
         if (len2) {
-                cmd = ring->cmd_base + ring->cmd_pos;
-                res = ring->res_base + ring->res_pos;
+                mtk_sha_ring_shift(ring, &cmd, &res, &count);
 
                 res->hdr = MTK_DESC_BUF_LEN(len2);
                 cmd->hdr = MTK_DESC_BUF_LEN(len2);
                 cmd->buf = cpu_to_le32(addr2);
-
-                if (++ring->cmd_pos == MTK_DESC_NUM)
-                        ring->cmd_pos = 0;
-
-                ring->res_pos = ring->cmd_pos;
-                count++;
         }
 
         cmd->hdr |= MTK_DESC_LAST;