| Message ID | 20200904112527.15677-1-nicolas.toromanoff@st.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | crypto: stm32/crc32 - Avoid lock if hardware is already used | expand |
On Fri, Sep 04, 2020 at 01:25:27PM +0200, Nicolas Toromanoff wrote: > 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> > --- > drivers/crypto/stm32/Kconfig | 2 ++ > drivers/crypto/stm32/stm32-crc32.c | 15 ++++++++++++--- > 2 files changed, 14 insertions(+), 3 deletions(-) > > diff --git a/drivers/crypto/stm32/Kconfig b/drivers/crypto/stm32/Kconfig > index 4ef3eb11361c..8d605b07571f 100644 > --- a/drivers/crypto/stm32/Kconfig > +++ b/drivers/crypto/stm32/Kconfig > @@ -3,6 +3,8 @@ config CRYPTO_DEV_STM32_CRC > tristate "Support for STM32 crc accelerators" > depends on ARCH_STM32 > select CRYPTO_HASH > + select CRYPTO_CRC32 > + select CRYPTO_CRC32C Shouldn't this be "select CRC32"? Thanks,
Hello Herbert, On 9/11/20 6:28 AM, Herbert Xu wrote: > On Fri, Sep 04, 2020 at 01:25:27PM +0200, Nicolas Toromanoff wrote: >> 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> >> --- >> drivers/crypto/stm32/Kconfig | 2 ++ >> drivers/crypto/stm32/stm32-crc32.c | 15 ++++++++++++--- >> 2 files changed, 14 insertions(+), 3 deletions(-) >> >> diff --git a/drivers/crypto/stm32/Kconfig b/drivers/crypto/stm32/Kconfig >> index 4ef3eb11361c..8d605b07571f 100644 >> --- a/drivers/crypto/stm32/Kconfig >> +++ b/drivers/crypto/stm32/Kconfig >> @@ -3,6 +3,8 @@ config CRYPTO_DEV_STM32_CRC >> tristate "Support for STM32 crc accelerators" >> depends on ARCH_STM32 >> select CRYPTO_HASH >> + select CRYPTO_CRC32 >> + select CRYPTO_CRC32C > > Shouldn't this be "select CRC32"? Correct "select CRC32" is enough. I'll send a version 2 with only "select CRC32". Nicolas.
diff --git a/drivers/crypto/stm32/Kconfig b/drivers/crypto/stm32/Kconfig index 4ef3eb11361c..8d605b07571f 100644 --- a/drivers/crypto/stm32/Kconfig +++ b/drivers/crypto/stm32/Kconfig @@ -3,6 +3,8 @@ config CRYPTO_DEV_STM32_CRC tristate "Support for STM32 crc accelerators" depends on ARCH_STM32 select CRYPTO_HASH + select CRYPTO_CRC32 + select CRYPTO_CRC32C 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 783a64f3f635..75867c0b0017 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/io.h> #include <linux/kernel.h> @@ -149,7 +150,6 @@ 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) @@ -157,7 +157,15 @@ 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 @@ -197,8 +205,9 @@ 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);
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> --- drivers/crypto/stm32/Kconfig | 2 ++ drivers/crypto/stm32/stm32-crc32.c | 15 ++++++++++++--- 2 files changed, 14 insertions(+), 3 deletions(-)