diff options
Diffstat (limited to 'drivers/crypto/stm32/stm32_crc32.c')
-rw-r--r-- | drivers/crypto/stm32/stm32_crc32.c | 144 |
1 files changed, 83 insertions, 61 deletions
diff --git a/drivers/crypto/stm32/stm32_crc32.c b/drivers/crypto/stm32/stm32_crc32.c index 440c9f1bd006..5da7d4a8aad4 100644 --- a/drivers/crypto/stm32/stm32_crc32.c +++ b/drivers/crypto/stm32/stm32_crc32.c @@ -28,8 +28,10 @@ /* Registers values */ #define CRC_CR_RESET BIT(0) -#define CRC_CR_REVERSE (BIT(7) | BIT(6) | BIT(5)) -#define CRC_INIT_DEFAULT 0xFFFFFFFF +#define CRC_CR_REV_IN_WORD (BIT(6) | BIT(5)) +#define CRC_CR_REV_IN_BYTE BIT(5) +#define CRC_CR_REV_OUT BIT(7) +#define CRC32C_INIT_DEFAULT 0xFFFFFFFF #define CRC_AUTOSUSPEND_DELAY 50 @@ -38,8 +40,6 @@ struct stm32_crc { struct device *dev; void __iomem *regs; struct clk *clk; - u8 pending_data[sizeof(u32)]; - size_t nb_pending_bytes; }; struct stm32_crc_list { @@ -59,14 +59,13 @@ struct stm32_crc_ctx { struct stm32_crc_desc_ctx { u32 partial; /* crc32c: partial in first 4 bytes of that struct */ - struct stm32_crc *crc; }; static int stm32_crc32_cra_init(struct crypto_tfm *tfm) { struct stm32_crc_ctx *mctx = crypto_tfm_ctx(tfm); - mctx->key = CRC_INIT_DEFAULT; + mctx->key = 0; mctx->poly = CRC32_POLY_LE; return 0; } @@ -75,7 +74,7 @@ static int stm32_crc32c_cra_init(struct crypto_tfm *tfm) { struct stm32_crc_ctx *mctx = crypto_tfm_ctx(tfm); - mctx->key = CRC_INIT_DEFAULT; + mctx->key = CRC32C_INIT_DEFAULT; mctx->poly = CRC32C_POLY_LE; return 0; } @@ -94,32 +93,42 @@ static int stm32_crc_setkey(struct crypto_shash *tfm, const u8 *key, return 0; } +static struct stm32_crc *stm32_crc_get_next_crc(void) +{ + struct stm32_crc *crc; + + spin_lock_bh(&crc_list.lock); + crc = list_first_entry(&crc_list.dev_list, struct stm32_crc, list); + if (crc) + list_move_tail(&crc->list, &crc_list.dev_list); + spin_unlock_bh(&crc_list.lock); + + return crc; +} + static int stm32_crc_init(struct shash_desc *desc) { struct stm32_crc_desc_ctx *ctx = shash_desc_ctx(desc); struct stm32_crc_ctx *mctx = crypto_shash_ctx(desc->tfm); struct stm32_crc *crc; - spin_lock_bh(&crc_list.lock); - list_for_each_entry(crc, &crc_list.dev_list, list) { - ctx->crc = crc; - break; - } - spin_unlock_bh(&crc_list.lock); + crc = stm32_crc_get_next_crc(); + if (!crc) + return -ENODEV; - pm_runtime_get_sync(ctx->crc->dev); + pm_runtime_get_sync(crc->dev); /* Reset, set key, poly and configure in bit reverse mode */ - writel_relaxed(bitrev32(mctx->key), ctx->crc->regs + CRC_INIT); - writel_relaxed(bitrev32(mctx->poly), ctx->crc->regs + CRC_POL); - writel_relaxed(CRC_CR_RESET | CRC_CR_REVERSE, ctx->crc->regs + CRC_CR); + writel_relaxed(bitrev32(mctx->key), crc->regs + CRC_INIT); + writel_relaxed(bitrev32(mctx->poly), crc->regs + CRC_POL); + writel_relaxed(CRC_CR_RESET | CRC_CR_REV_IN_WORD | CRC_CR_REV_OUT, + crc->regs + CRC_CR); /* Store partial result */ - ctx->partial = readl_relaxed(ctx->crc->regs + CRC_DR); - ctx->crc->nb_pending_bytes = 0; + ctx->partial = readl_relaxed(crc->regs + CRC_DR); - pm_runtime_mark_last_busy(ctx->crc->dev); - pm_runtime_put_autosuspend(ctx->crc->dev); + pm_runtime_mark_last_busy(crc->dev); + pm_runtime_put_autosuspend(crc->dev); return 0; } @@ -128,31 +137,49 @@ static int stm32_crc_update(struct shash_desc *desc, const u8 *d8, unsigned int length) { struct stm32_crc_desc_ctx *ctx = shash_desc_ctx(desc); - struct stm32_crc *crc = ctx->crc; - u32 *d32; - unsigned int i; + struct stm32_crc_ctx *mctx = crypto_shash_ctx(desc->tfm); + struct stm32_crc *crc; + + crc = stm32_crc_get_next_crc(); + if (!crc) + return -ENODEV; pm_runtime_get_sync(crc->dev); - if (unlikely(crc->nb_pending_bytes)) { - while (crc->nb_pending_bytes != sizeof(u32) && length) { - /* Fill in pending data */ - crc->pending_data[crc->nb_pending_bytes++] = *(d8++); + /* + * Restore previously calculated CRC for this context as init value + * Restore polynomial configuration + * Configure in register for word input data, + * Configure out register in reversed bit mode data. + */ + writel_relaxed(bitrev32(ctx->partial), crc->regs + CRC_INIT); + writel_relaxed(bitrev32(mctx->poly), crc->regs + CRC_POL); + writel_relaxed(CRC_CR_RESET | CRC_CR_REV_IN_WORD | CRC_CR_REV_OUT, + crc->regs + CRC_CR); + + if (d8 != PTR_ALIGN(d8, sizeof(u32))) { + /* Configure for byte data */ + writel_relaxed(CRC_CR_REV_IN_BYTE | CRC_CR_REV_OUT, + crc->regs + CRC_CR); + while (d8 != PTR_ALIGN(d8, sizeof(u32)) && length) { + writeb_relaxed(*d8++, crc->regs + CRC_DR); length--; } - - if (crc->nb_pending_bytes == sizeof(u32)) { - /* Process completed pending data */ - writel_relaxed(*(u32 *)crc->pending_data, - crc->regs + CRC_DR); - crc->nb_pending_bytes = 0; - } + /* Configure for word data */ + writel_relaxed(CRC_CR_REV_IN_WORD | CRC_CR_REV_OUT, + crc->regs + CRC_CR); } - d32 = (u32 *)d8; - for (i = 0; i < length >> 2; i++) - /* Process 32 bits data */ - writel_relaxed(*(d32++), crc->regs + CRC_DR); + for (; length >= sizeof(u32); d8 += sizeof(u32), length -= sizeof(u32)) + writel_relaxed(*((u32 *)d8), crc->regs + CRC_DR); + + if (length) { + /* Configure for byte data */ + writel_relaxed(CRC_CR_REV_IN_BYTE | CRC_CR_REV_OUT, + crc->regs + CRC_CR); + while (length--) + writeb_relaxed(*d8++, crc->regs + CRC_DR); + } /* Store partial result */ ctx->partial = readl_relaxed(crc->regs + CRC_DR); @@ -160,22 +187,6 @@ static int stm32_crc_update(struct shash_desc *desc, const u8 *d8, pm_runtime_mark_last_busy(crc->dev); pm_runtime_put_autosuspend(crc->dev); - /* Check for pending data (non 32 bits) */ - length &= 3; - if (likely(!length)) - return 0; - - if ((crc->nb_pending_bytes + length) >= sizeof(u32)) { - /* Shall not happen */ - dev_err(crc->dev, "Pending data overflow\n"); - return -EINVAL; - } - - d8 = (const u8 *)d32; - for (i = 0; i < length; i++) - /* Store pending data */ - crc->pending_data[crc->nb_pending_bytes++] = *(d8++); - return 0; } @@ -204,6 +215,8 @@ static int stm32_crc_digest(struct shash_desc *desc, const u8 *data, return stm32_crc_init(desc) ?: stm32_crc_finup(desc, data, length, out); } +static unsigned int refcnt; +static DEFINE_MUTEX(refcnt_lock); static struct shash_alg algs[] = { /* CRC-32 */ { @@ -296,12 +309,18 @@ static int stm32_crc_probe(struct platform_device *pdev) list_add(&crc->list, &crc_list.dev_list); spin_unlock(&crc_list.lock); - ret = crypto_register_shashes(algs, ARRAY_SIZE(algs)); - if (ret) { - dev_err(dev, "Failed to register\n"); - clk_disable_unprepare(crc->clk); - return ret; + mutex_lock(&refcnt_lock); + if (!refcnt) { + ret = crypto_register_shashes(algs, ARRAY_SIZE(algs)); + if (ret) { + mutex_unlock(&refcnt_lock); + dev_err(dev, "Failed to register\n"); + clk_disable_unprepare(crc->clk); + return ret; + } } + refcnt++; + mutex_unlock(&refcnt_lock); dev_info(dev, "Initialized\n"); @@ -322,7 +341,10 @@ static int stm32_crc_remove(struct platform_device *pdev) list_del(&crc->list); spin_unlock(&crc_list.lock); - crypto_unregister_shashes(algs, ARRAY_SIZE(algs)); + mutex_lock(&refcnt_lock); + if (!--refcnt) + crypto_unregister_shashes(algs, ARRAY_SIZE(algs)); + mutex_unlock(&refcnt_lock); pm_runtime_disable(crc->dev); pm_runtime_put_noidle(crc->dev); |