The FSM hardware works by setting a predetermined sequence of register writes. Rather than open coding them inside each functional block we're going to define them in a series of formatted 'sequence structures'. This patch provides the framework which shall be used for every action.
Acked-by Angus Clark <[email protected]> Signed-off-by: Lee Jones <[email protected]> --- drivers/mtd/devices/st_spi_fsm.c | 56 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 56 insertions(+) diff --git a/drivers/mtd/devices/st_spi_fsm.c b/drivers/mtd/devices/st_spi_fsm.c index 40952f9..ac6b782 100644 --- a/drivers/mtd/devices/st_spi_fsm.c +++ b/drivers/mtd/devices/st_spi_fsm.c @@ -194,6 +194,8 @@ #define STFSM_FLASH_SAFE_FREQ 10000000UL /* 10 MHz */ +#define STFSM_MAX_WAIT_SEQ_MS 1000 /* FSM execution time */ + struct stfsm { struct device *dev; void __iomem *base; @@ -204,6 +206,24 @@ struct stfsm { uint32_t fifo_dir_delay; }; +struct stfsm_seq { + uint32_t data_size; + uint32_t addr1; + uint32_t addr2; + uint32_t addr_cfg; + uint32_t seq_opc[5]; + uint32_t mode; + uint32_t dummy; + uint32_t status; + uint8_t seq[16]; + uint32_t seq_cfg; +} __packed __aligned(4); + +static inline int stfsm_is_idle(struct stfsm *fsm) +{ + return readl(fsm->base + SPI_FAST_SEQ_STA) & 0x10; +} + static inline uint32_t stfsm_fifo_available(struct stfsm *fsm) { return (readl(fsm->base + SPI_FAST_SEQ_STA) >> 5) & 0x7f; @@ -225,6 +245,42 @@ static void stfsm_clear_fifo(struct stfsm *fsm) } } +static inline void stfsm_load_seq(struct stfsm *fsm, + const struct stfsm_seq *seq) +{ + void __iomem *dst = fsm->base + SPI_FAST_SEQ_TRANSFER_SIZE; + const uint32_t *src = (const uint32_t *)seq; + int words = sizeof(*seq) / sizeof(*src); + + BUG_ON(!stfsm_is_idle(fsm)); + + while (words--) { + writel(*src, dst); + src++; + dst += 4; + } +} + +static void stfsm_wait_seq(struct stfsm *fsm) +{ + unsigned long deadline; + int timeout = 0; + + deadline = jiffies + msecs_to_jiffies(STFSM_MAX_WAIT_SEQ_MS); + + while (!timeout) { + if (time_after_eq(jiffies, deadline)) + timeout = 1; + + if (stfsm_is_idle(fsm)) + return; + + cond_resched(); + } + + dev_err(fsm->dev, "timeout on sequence completion\n"); +} + static int stfsm_set_mode(struct stfsm *fsm, uint32_t mode) { int ret, timeout = 10; -- 1.8.3.2 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
