Hi Boris,
On 8/24/2018 8:48 PM, Boris Brezillon wrote:
On Wed, 22 Aug 2018 22:08:42 +0800
Liang Yang <liang.yang@xxxxxxxxxxx> wrote:
You have to wait tWB, that's for sure.
we have a maximum 32 commands fifo. when command is written into
NFC_REG_CMD, it doesn't mean that command is executing right now, maybe
it is buffering on the queue.Assume one ERASE operation, when 2nd
command(0xd0) is written into NFC_REG_CMD and then come into
NAND_OP_WAITRDY_INSTR, if I read the RB status by register, it may be
wrong because 0xd0 may not being executed. it is unusual unless
buffering two many command.
You should flush the queue and wait for it to empty at the end of
->exec_op().
so it seems that i still need to use nand_soft_waitrdy or wait cmd is
executed somewhere.
Don't you have a WAIT_FOR_RB instruction? What is NFC_CMD_RB for? Also,
NFC_CMD_IDLE seems to allow you to add an arbitrary delay, and that's
probably what you should use for tWB.
em, I can wait for RB by reading the status from register now. but when
calling nand_soft_waitrdy, i really met a problem. One *jiffies* is
about 4ms. When programming, it pass 1ms to
instr->ctx.waitrdy.timeout_ms and nand_soft_waitrdy will be only one
*jiffies* to reach timeout. And then calling nand_soft_waitrdy maybe at
the tail of 4ms interval, it may only wait 100us and next jiffies
arrive. Is it correct?
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