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| author | Nicolas Toromanoff <nicolas.toromanoff@st.com> | 2020-09-16 09:33:44 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-10-29 12:07:23 +0300 |
| commit | 9748e867ac817de34c62e37a0d47de86ffac5656 (patch) | |
| tree | e6b54fe96c495e712ca5897f7253a2233eba53cb /drivers/crypto | |
| parent | aee35828de8859987cc24d0fbc189ffbfe1e3568 (diff) | |
| download | linux-9748e867ac817de34c62e37a0d47de86ffac5656.tar.xz | |
crypto: stm32/crc32 - Avoid lock if hardware is already used
[ Upstream commit bbf2cb1ea1e1428589d7f4d652bed15b265ce92d ]
If STM32 CRC device is already in use, calculate CRC by software.
This will release CPU constraint for a concurrent access to the
hardware, and avoid masking irqs during the whole block processing.
Fixes: 7795c0baf5ac ("crypto: stm32/crc32 - protect from concurrent accesses")
Signed-off-by: Nicolas Toromanoff <nicolas.toromanoff@st.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'drivers/crypto')
| -rw-r--r-- | drivers/crypto/stm32/Kconfig | 1 | ||||
| -rw-r--r-- | drivers/crypto/stm32/stm32-crc32.c | 15 |
2 files changed, 13 insertions, 3 deletions
diff --git a/drivers/crypto/stm32/Kconfig b/drivers/crypto/stm32/Kconfig index 4ef3eb11361c..4a4c3284ae1f 100644 --- a/drivers/crypto/stm32/Kconfig +++ b/drivers/crypto/stm32/Kconfig @@ -3,6 +3,7 @@ config CRYPTO_DEV_STM32_CRC tristate "Support for STM32 crc accelerators" depends on ARCH_STM32 select CRYPTO_HASH + select CRC32 help This enables support for the CRC32 hw accelerator which can be found on STMicroelectronics STM32 SOC. diff --git a/drivers/crypto/stm32/stm32-crc32.c b/drivers/crypto/stm32/stm32-crc32.c index 3ba41148c2a4..2c13f5214d2c 100644 --- a/drivers/crypto/stm32/stm32-crc32.c +++ b/drivers/crypto/stm32/stm32-crc32.c @@ -6,6 +6,7 @@ #include <linux/bitrev.h> #include <linux/clk.h> +#include <linux/crc32.h> #include <linux/crc32poly.h> #include <linux/module.h> #include <linux/mod_devicetable.h> @@ -147,7 +148,6 @@ static int burst_update(struct shash_desc *desc, const u8 *d8, struct stm32_crc_desc_ctx *ctx = shash_desc_ctx(desc); struct stm32_crc_ctx *mctx = crypto_shash_ctx(desc->tfm); struct stm32_crc *crc; - unsigned long flags; crc = stm32_crc_get_next_crc(); if (!crc) @@ -155,7 +155,15 @@ static int burst_update(struct shash_desc *desc, const u8 *d8, pm_runtime_get_sync(crc->dev); - spin_lock_irqsave(&crc->lock, flags); + if (!spin_trylock(&crc->lock)) { + /* Hardware is busy, calculate crc32 by software */ + if (mctx->poly == CRC32_POLY_LE) + ctx->partial = crc32_le(ctx->partial, d8, length); + else + ctx->partial = __crc32c_le(ctx->partial, d8, length); + + goto pm_out; + } /* * Restore previously calculated CRC for this context as init value @@ -195,8 +203,9 @@ static int burst_update(struct shash_desc *desc, const u8 *d8, /* Store partial result */ ctx->partial = readl_relaxed(crc->regs + CRC_DR); - spin_unlock_irqrestore(&crc->lock, flags); + spin_unlock(&crc->lock); +pm_out: pm_runtime_mark_last_busy(crc->dev); pm_runtime_put_autosuspend(crc->dev); |