| Message ID | 20210518134332.17826-2-patrice.chotard@foss.st.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | MTD: spinand: Add spi_mem_poll_status() support | expand |
On Tue, 18 May 2021 15:43:30 +0200 <patrice.chotard@foss.st.com> wrote: > From: Patrice Chotard <patrice.chotard@foss.st.com> > > With STM32 QSPI, it is possible to poll the status register of the device. > This could be done to offload the CPU during an operation (erase or > program a SPI NAND for example). > > spi_mem_poll_status API has been added to handle this feature. > This new function take care of the offload/non-offload cases. > > For the non-offload case, use read_poll_timeout() to poll the status in > order to release CPU during this phase. > For example, previously, when erasing large area, in non-offload case, > CPU load can reach ~50%, now it decrease to ~35%. > > Signed-off-by: Patrice Chotard <patrice.chotard@foss.st.com> > Signed-off-by: Christophe Kerello <christophe.kerello@foss.st.com> > --- > Changes in v4: > - Remove init_completion() from spi_mem_probe() added in v2. > - Add missing static for spi_mem_read_status(). > - Check if operation in spi_mem_poll_status() is a READ. > > Changes in v3: > - Add spi_mem_read_status() which allows to read 8 or 16 bits status. > - Add initial_delay_us and polling_delay_us parameters to spi_mem_poll_status() > and also to poll_status() callback. > - Move spi_mem_supports_op() in SW-based polling case. > - Add delay before invoking read_poll_timeout(). > - Remove the reinit/wait_for_completion() added in v2. > > Changes in v2: > - Indicates the spi_mem_poll_status() timeout unit > - Use 2-byte wide status register > - Add spi_mem_supports_op() call in spi_mem_poll_status() > - Add completion management in spi_mem_poll_status() > - Add offload/non-offload case management in spi_mem_poll_status() > - Optimize the non-offload case by using read_poll_timeout() > > drivers/spi/spi-mem.c | 85 +++++++++++++++++++++++++++++++++++++ > include/linux/spi/spi-mem.h | 14 ++++++ > 2 files changed, 99 insertions(+) > > diff --git a/drivers/spi/spi-mem.c b/drivers/spi/spi-mem.c > index 1513553e4080..97c7a83686c7 100644 > --- a/drivers/spi/spi-mem.c > +++ b/drivers/spi/spi-mem.c > @@ -6,6 +6,7 @@ > * Author: Boris Brezillon <boris.brezillon@bootlin.com> > */ > #include <linux/dmaengine.h> > +#include <linux/iopoll.h> > #include <linux/pm_runtime.h> > #include <linux/spi/spi.h> > #include <linux/spi/spi-mem.h> > @@ -743,6 +744,90 @@ static inline struct spi_mem_driver *to_spi_mem_drv(struct device_driver *drv) > return container_of(drv, struct spi_mem_driver, spidrv.driver); > } > > +static int spi_mem_read_status(struct spi_mem *mem, > + const struct spi_mem_op *op, > + u16 *status) > +{ > + const u8 *bytes = (u8 *)op->data.buf.in; > + int ret; > + > + ret = spi_mem_exec_op(mem, op); > + if (ret) > + return ret; > + > + if (op->data.nbytes > 1) > + *status = ((u16)bytes[0] << 8) | bytes[1]; > + else > + *status = bytes[0]; > + > + return 0; > +} > + > +/** > + * spi_mem_poll_status() - Poll memory device status > + * @mem: SPI memory device > + * @op: the memory operation to execute > + * @mask: status bitmask to ckeck > + * @match: (status & mask) expected value > + * @initial_delay_us: delay in us before starting to poll > + * @polling_delay_us: time to sleep between reads in us > + * @timeout_ms: timeout in milliseconds > + * > + * This function send a polling status request to the controller driver " This function polls a status register and returns when (status & mask) == match or when the timeout has expired. " > + * > + * Return: 0 in case of success, -ETIMEDOUT in case of error, > + * -EOPNOTSUPP if not supported. > + */ > +int spi_mem_poll_status(struct spi_mem *mem, > + const struct spi_mem_op *op, > + u16 mask, u16 match, > + unsigned long initial_delay_us, > + unsigned long polling_delay_us, > + u16 timeout_ms) > +{ > + struct spi_controller *ctlr = mem->spi->controller; > + int ret = -EOPNOTSUPP; > + int read_status_ret; > + u16 status; > + > + if (op->data.nbytes < 1 || op->data.nbytes > 2 || > + op->data.dir != SPI_MEM_DATA_IN) > + return (-EINVAL); s/return (-EINVAL);/return -EINVAL;/ [...] > /** > @@ -369,6 +376,13 @@ devm_spi_mem_dirmap_create(struct device *dev, struct spi_mem *mem, > void devm_spi_mem_dirmap_destroy(struct device *dev, > struct spi_mem_dirmap_desc *desc); > > +int spi_mem_poll_status(struct spi_mem *mem, > + const struct spi_mem_op *op, > + u16 mask, u16 match, > + unsigned long initial_delay_us, > + unsigned long polling_delay_us, > + u16 timeout); s/timeout/timeout_ms/. With those minor things fixed Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com> > + > int spi_mem_driver_register_with_owner(struct spi_mem_driver *drv, > struct module *owner); >
On 5/18/21 4:12 PM, Boris Brezillon wrote: > On Tue, 18 May 2021 15:43:30 +0200 > <patrice.chotard@foss.st.com> wrote: > >> From: Patrice Chotard <patrice.chotard@foss.st.com> >> >> With STM32 QSPI, it is possible to poll the status register of the device. >> This could be done to offload the CPU during an operation (erase or >> program a SPI NAND for example). >> >> spi_mem_poll_status API has been added to handle this feature. >> This new function take care of the offload/non-offload cases. >> >> For the non-offload case, use read_poll_timeout() to poll the status in >> order to release CPU during this phase. >> For example, previously, when erasing large area, in non-offload case, >> CPU load can reach ~50%, now it decrease to ~35%. >> >> Signed-off-by: Patrice Chotard <patrice.chotard@foss.st.com> >> Signed-off-by: Christophe Kerello <christophe.kerello@foss.st.com> >> --- >> Changes in v4: >> - Remove init_completion() from spi_mem_probe() added in v2. >> - Add missing static for spi_mem_read_status(). >> - Check if operation in spi_mem_poll_status() is a READ. >> >> Changes in v3: >> - Add spi_mem_read_status() which allows to read 8 or 16 bits status. >> - Add initial_delay_us and polling_delay_us parameters to spi_mem_poll_status() >> and also to poll_status() callback. >> - Move spi_mem_supports_op() in SW-based polling case. >> - Add delay before invoking read_poll_timeout(). >> - Remove the reinit/wait_for_completion() added in v2. >> >> Changes in v2: >> - Indicates the spi_mem_poll_status() timeout unit >> - Use 2-byte wide status register >> - Add spi_mem_supports_op() call in spi_mem_poll_status() >> - Add completion management in spi_mem_poll_status() >> - Add offload/non-offload case management in spi_mem_poll_status() >> - Optimize the non-offload case by using read_poll_timeout() >> >> drivers/spi/spi-mem.c | 85 +++++++++++++++++++++++++++++++++++++ >> include/linux/spi/spi-mem.h | 14 ++++++ >> 2 files changed, 99 insertions(+) >> >> diff --git a/drivers/spi/spi-mem.c b/drivers/spi/spi-mem.c >> index 1513553e4080..97c7a83686c7 100644 >> --- a/drivers/spi/spi-mem.c >> +++ b/drivers/spi/spi-mem.c >> @@ -6,6 +6,7 @@ >> * Author: Boris Brezillon <boris.brezillon@bootlin.com> >> */ >> #include <linux/dmaengine.h> >> +#include <linux/iopoll.h> >> #include <linux/pm_runtime.h> >> #include <linux/spi/spi.h> >> #include <linux/spi/spi-mem.h> >> @@ -743,6 +744,90 @@ static inline struct spi_mem_driver *to_spi_mem_drv(struct device_driver *drv) >> return container_of(drv, struct spi_mem_driver, spidrv.driver); >> } >> >> +static int spi_mem_read_status(struct spi_mem *mem, >> + const struct spi_mem_op *op, >> + u16 *status) >> +{ >> + const u8 *bytes = (u8 *)op->data.buf.in; >> + int ret; >> + >> + ret = spi_mem_exec_op(mem, op); >> + if (ret) >> + return ret; >> + >> + if (op->data.nbytes > 1) >> + *status = ((u16)bytes[0] << 8) | bytes[1]; >> + else >> + *status = bytes[0]; >> + >> + return 0; >> +} >> + >> +/** >> + * spi_mem_poll_status() - Poll memory device status >> + * @mem: SPI memory device >> + * @op: the memory operation to execute >> + * @mask: status bitmask to ckeck >> + * @match: (status & mask) expected value >> + * @initial_delay_us: delay in us before starting to poll >> + * @polling_delay_us: time to sleep between reads in us >> + * @timeout_ms: timeout in milliseconds >> + * >> + * This function send a polling status request to the controller driver > > " > This function polls a status register and returns when > (status & mask) == match or when the timeout has expired. > " Ok i will update spi_mem_poll_status description > >> + * >> + * Return: 0 in case of success, -ETIMEDOUT in case of error, >> + * -EOPNOTSUPP if not supported. >> + */ >> +int spi_mem_poll_status(struct spi_mem *mem, >> + const struct spi_mem_op *op, >> + u16 mask, u16 match, >> + unsigned long initial_delay_us, >> + unsigned long polling_delay_us, >> + u16 timeout_ms) >> +{ >> + struct spi_controller *ctlr = mem->spi->controller; >> + int ret = -EOPNOTSUPP; >> + int read_status_ret; >> + u16 status; >> + >> + if (op->data.nbytes < 1 || op->data.nbytes > 2 || >> + op->data.dir != SPI_MEM_DATA_IN) >> + return (-EINVAL); > > s/return (-EINVAL);/return -EINVAL;/ Ok > > > [...] > >> /** >> @@ -369,6 +376,13 @@ devm_spi_mem_dirmap_create(struct device *dev, struct spi_mem *mem, >> void devm_spi_mem_dirmap_destroy(struct device *dev, >> struct spi_mem_dirmap_desc *desc); >> >> +int spi_mem_poll_status(struct spi_mem *mem, >> + const struct spi_mem_op *op, >> + u16 mask, u16 match, >> + unsigned long initial_delay_us, >> + unsigned long polling_delay_us, >> + u16 timeout); > > s/timeout/timeout_ms/. Ok > > With those minor things fixed > > Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com> Thanks Patrice > >> + >> int spi_mem_driver_register_with_owner(struct spi_mem_driver *drv, >> struct module *owner); >> >
diff --git a/drivers/spi/spi-mem.c b/drivers/spi/spi-mem.c index 1513553e4080..97c7a83686c7 100644 --- a/drivers/spi/spi-mem.c +++ b/drivers/spi/spi-mem.c @@ -6,6 +6,7 @@ * Author: Boris Brezillon <boris.brezillon@bootlin.com> */ #include <linux/dmaengine.h> +#include <linux/iopoll.h> #include <linux/pm_runtime.h> #include <linux/spi/spi.h> #include <linux/spi/spi-mem.h> @@ -743,6 +744,90 @@ static inline struct spi_mem_driver *to_spi_mem_drv(struct device_driver *drv) return container_of(drv, struct spi_mem_driver, spidrv.driver); } +static int spi_mem_read_status(struct spi_mem *mem, + const struct spi_mem_op *op, + u16 *status) +{ + const u8 *bytes = (u8 *)op->data.buf.in; + int ret; + + ret = spi_mem_exec_op(mem, op); + if (ret) + return ret; + + if (op->data.nbytes > 1) + *status = ((u16)bytes[0] << 8) | bytes[1]; + else + *status = bytes[0]; + + return 0; +} + +/** + * spi_mem_poll_status() - Poll memory device status + * @mem: SPI memory device + * @op: the memory operation to execute + * @mask: status bitmask to ckeck + * @match: (status & mask) expected value + * @initial_delay_us: delay in us before starting to poll + * @polling_delay_us: time to sleep between reads in us + * @timeout_ms: timeout in milliseconds + * + * This function send a polling status request to the controller driver + * + * Return: 0 in case of success, -ETIMEDOUT in case of error, + * -EOPNOTSUPP if not supported. + */ +int spi_mem_poll_status(struct spi_mem *mem, + const struct spi_mem_op *op, + u16 mask, u16 match, + unsigned long initial_delay_us, + unsigned long polling_delay_us, + u16 timeout_ms) +{ + struct spi_controller *ctlr = mem->spi->controller; + int ret = -EOPNOTSUPP; + int read_status_ret; + u16 status; + + if (op->data.nbytes < 1 || op->data.nbytes > 2 || + op->data.dir != SPI_MEM_DATA_IN) + return (-EINVAL); + + if (ctlr->mem_ops && ctlr->mem_ops->poll_status) { + ret = spi_mem_access_start(mem); + if (ret) + return ret; + + ret = ctlr->mem_ops->poll_status(mem, op, mask, match, + initial_delay_us, polling_delay_us, + timeout_ms); + + spi_mem_access_end(mem); + } + + if (ret == -EOPNOTSUPP) { + if (!spi_mem_supports_op(mem, op)) + return ret; + + if (initial_delay_us < 10) + udelay(initial_delay_us); + else + usleep_range((initial_delay_us >> 2) + 1, + initial_delay_us); + + ret = read_poll_timeout(spi_mem_read_status, read_status_ret, + (read_status_ret || ((status) & mask) == match), + polling_delay_us, timeout_ms * 1000, false, mem, + op, &status); + if (read_status_ret) + return read_status_ret; + } + + return ret; +} +EXPORT_SYMBOL_GPL(spi_mem_poll_status); + static int spi_mem_probe(struct spi_device *spi) { struct spi_mem_driver *memdrv = to_spi_mem_drv(spi->dev.driver); diff --git a/include/linux/spi/spi-mem.h b/include/linux/spi/spi-mem.h index 2b65c9edc34e..10375d9ad747 100644 --- a/include/linux/spi/spi-mem.h +++ b/include/linux/spi/spi-mem.h @@ -250,6 +250,7 @@ static inline void *spi_mem_get_drvdata(struct spi_mem *mem) * the currently mapped area), and the caller of * spi_mem_dirmap_write() is responsible for calling it again in * this case. + * @poll_status: poll memory device status * * This interface should be implemented by SPI controllers providing an * high-level interface to execute SPI memory operation, which is usually the @@ -274,6 +275,12 @@ struct spi_controller_mem_ops { u64 offs, size_t len, void *buf); ssize_t (*dirmap_write)(struct spi_mem_dirmap_desc *desc, u64 offs, size_t len, const void *buf); + int (*poll_status)(struct spi_mem *mem, + const struct spi_mem_op *op, + u16 mask, u16 match, + unsigned long initial_delay_us, + unsigned long polling_rate_us, + unsigned long timeout_ms); }; /** @@ -369,6 +376,13 @@ devm_spi_mem_dirmap_create(struct device *dev, struct spi_mem *mem, void devm_spi_mem_dirmap_destroy(struct device *dev, struct spi_mem_dirmap_desc *desc); +int spi_mem_poll_status(struct spi_mem *mem, + const struct spi_mem_op *op, + u16 mask, u16 match, + unsigned long initial_delay_us, + unsigned long polling_delay_us, + u16 timeout); + int spi_mem_driver_register_with_owner(struct spi_mem_driver *drv, struct module *owner);