mtd: st_spi_fsm: Supply framework for device requests

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 <angus.clark@st.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
This commit is contained in:
Lee Jones 2014-03-20 09:20:36 +00:00 committed by Brian Norris
parent 86f309fd8f
commit 3c8b85b340

View file

@ -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;