drivers/crypto/inside-secure/safexcel_ring.c

   1 /*
   2  * Copyright (C) 2017 Marvell
   3  *
   4  * Antoine Tenart <antoine.tenart@free-electrons.com>
   5  *
   6  * This file is licensed under the terms of the GNU General Public
   7  * License version 2. This program is licensed "as is" without any
   8  * warranty of any kind, whether express or implied.
   9  */
  10
  11 #include <linux/dma-mapping.h>
  12 #include <linux/spinlock.h>
  13
  14 #include "safexcel.h"
  15
  16 int safexcel_init_ring_descriptors(struct safexcel_crypto_priv *priv,
  17                                    struct safexcel_ring *cdr,
  18                                    struct safexcel_ring *rdr)
  19 {
  20         cdr->offset = sizeof(u32) * priv->config.cd_offset;
  21         cdr->base = dmam_alloc_coherent(priv->dev,
  22                                         cdr->offset * EIP197_DEFAULT_RING_SIZE,
  23                                         &cdr->base_dma, GFP_KERNEL);
  24         if (!cdr->base)
  25                 return -ENOMEM;
  26         cdr->write = cdr->base;
  27         cdr->base_end = cdr->base + cdr->offset * EIP197_DEFAULT_RING_SIZE;
  28         cdr->read = cdr->base;
  29
  30         rdr->offset = sizeof(u32) * priv->config.rd_offset;
  31         rdr->base = dmam_alloc_coherent(priv->dev,
  32                                         rdr->offset * EIP197_DEFAULT_RING_SIZE,
  33                                         &rdr->base_dma, GFP_KERNEL);
  34         if (!rdr->base)
  35                 return -ENOMEM;
  36         rdr->write = rdr->base;
  37         rdr->base_end = rdr->base + rdr->offset * EIP197_DEFAULT_RING_SIZE;
  38         rdr->read = rdr->base;
  39
  40         return 0;
  41 }
  42
  43 inline int safexcel_select_ring(struct safexcel_crypto_priv *priv)
  44 {
  45         return (atomic_inc_return(&priv->ring_used) % priv->config.rings);
  46 }
  47
  48 static void *safexcel_ring_next_wptr(struct safexcel_crypto_priv *priv,
  49                                      struct safexcel_ring *ring)
  50 {
  51         void *ptr = ring->write;
  52
  53         if (ring->nr == EIP197_DEFAULT_RING_SIZE - 1)
  54                 return ERR_PTR(-ENOMEM);
  55
  56         ring->write += ring->offset;
  57         if (ring->write == ring->base_end)
  58                 ring->write = ring->base;
  59
  60         ring->nr++;
  61         return ptr;
  62 }
  63
  64 void *safexcel_ring_next_rptr(struct safexcel_crypto_priv *priv,
  65                               struct safexcel_ring *ring)
  66 {
  67         void *ptr = ring->read;
  68
  69         if (!ring->nr)
  70                 return ERR_PTR(-ENOENT);
  71
  72         ring->read += ring->offset;
  73         if (ring->read == ring->base_end)
  74                 ring->read = ring->base;
  75
  76         ring->nr--;
  77         return ptr;
  78 }
  79
  80 void safexcel_ring_rollback_wptr(struct safexcel_crypto_priv *priv,
  81                                  struct safexcel_ring *ring)
  82 {
  83         if (!ring->nr)
  84                 return;
  85
  86         if (ring->write == ring->base)
  87                 ring->write = ring->base_end - ring->offset;
  88         else
  89                 ring->write -= ring->offset;
  90
  91         ring->nr--;
  92 }
  93
  94 struct safexcel_command_desc *safexcel_add_cdesc(struct safexcel_crypto_priv *priv,
  95                                                  int ring_id,
  96                                                  bool first, bool last,
  97                                                  dma_addr_t data, u32 data_len,
  98                                                  u32 full_data_len,
  99                                                  dma_addr_t context) {
 100         struct safexcel_command_desc *cdesc;
 101         int i;
 102
 103         cdesc = safexcel_ring_next_wptr(priv, &priv->ring[ring_id].cdr);
 104         if (IS_ERR(cdesc))
 105                 return cdesc;
 106
 107         memset(cdesc, 0, sizeof(struct safexcel_command_desc));
 108
 109         cdesc->first_seg = first;
 110         cdesc->last_seg = last;
 111         cdesc->particle_size = data_len;
 112         cdesc->data_lo = lower_32_bits(data);
 113         cdesc->data_hi = upper_32_bits(data);
 114
 115         if (first && context) {
 116                 struct safexcel_token *token =
 117                         (struct safexcel_token *)cdesc->control_data.token;
 118
 119                 cdesc->control_data.packet_length = full_data_len;
 120                 cdesc->control_data.options = EIP197_OPTION_MAGIC_VALUE |
 121                                               EIP197_OPTION_64BIT_CTX |
 122                                               EIP197_OPTION_CTX_CTRL_IN_CMD;
 123                 cdesc->control_data.context_lo =
 124                         (lower_32_bits(context) & GENMASK(31, 2)) >> 2;
 125                 cdesc->control_data.context_hi = upper_32_bits(context);
 126
 127                 /* TODO: large xform HMAC with SHA-384/512 uses refresh = 3 */
 128                 cdesc->control_data.refresh = 2;
 129
 130                 for (i = 0; i < EIP197_MAX_TOKENS; i++)
 131                         eip197_noop_token(&token[i]);
 132         }
 133
 134         return cdesc;
 135 }
 136
 137 struct safexcel_result_desc *safexcel_add_rdesc(struct safexcel_crypto_priv *priv,
 138                                                 int ring_id,
 139                                                 bool first, bool last,
 140                                                 dma_addr_t data, u32 len)
 141 {
 142         struct safexcel_result_desc *rdesc;
 143
 144         rdesc = safexcel_ring_next_wptr(priv, &priv->ring[ring_id].rdr);
 145         if (IS_ERR(rdesc))
 146                 return rdesc;
 147
 148         memset(rdesc, 0, sizeof(struct safexcel_result_desc));
 149
 150         rdesc->first_seg = first;
 151         rdesc->last_seg = last;
 152         rdesc->particle_size = len;
 153         rdesc->data_lo = lower_32_bits(data);
 154         rdesc->data_hi = upper_32_bits(data);
 155
 156         return rdesc;
 157 }