[PATCH] mtd: rawnand: qcom: update last code word register
miquel.raynal at bootlin.com
Wed Feb 24 01:48:50 EST 2021
mdalam at codeaurora.org wrote on Wed, 24 Feb 2021 10:09:48 +0530:
> On 2021-02-24 01:13, mdalam at codeaurora.org wrote:
> > On 2021-02-23 22:04, Miquel Raynal wrote:
> >> Hello,
> >> >> Md Sadre Alam <mdalam at codeaurora.org> wrote on Tue, 23 Feb 2021
> >> 01:34:27 +0530:
> >> >>> From QPIC version 2.0 onwards new register got added to read last
> >> >> a new
> >> >>> codeword. This change will add the READ_LOCATION_LAST_CW_n register.
> >> >> Add support for this READ_LOCATION_LAST_CW_n register.
> >> >>> >>> For first three code word READ_LOCATION_n register will be
> >>> use.For last code word READ_LOCATION_LAST_CW_n register will be
> >>> use.
> >> >> "
> >> In the case of QPIC v2, codewords 0, 1 and 2 will be accessed through
> >> READ_LOCATION_n, while codeword 3 will be accessed through
> >> READ_LOCATION_LAST_CW_n.
> >> "
> >> >> When I read my own sentence, I feel that there is something wrong.
> >> If there are only 4 codewords, I guess a QPIC v2 is able to use
> >> READ_LOCATION_3 or READ_LOCATION_LAST_CW_0 interchangeably. Isn't it?
> >> >> I guess the point of having these "last_cw_n" registers is to support
> >> up to 8 codewords, am I wrong? If this the case, the current patch
> >> completely fails doing that I don't get the point of such change.
> > This register is only use to read last code word.
> > I have address all the comments from all the previous sub sequent
> > patches and pushed
> > all patches in only one series.
> > Please check.
> The registers READ_LOCATION & READ_LOCATION_LAST are not associated with number of code words.
> These two registers are used to access the location inside a code word.
Ok. Can you please explain what is a location then? Or point me to a
datasheet that explains it.
Bottom line question: why having READ_LOCATION_0, _1,... an
READ_LOCATION_LAST_0, _1, etc?
> So whether we are having 4 code words
> or 8 code words it doesn't matter. If we wanted access the location within normal code word we have to
> use READ_LOCATION register and if we wanted to access location in last code word then we have to use
> >> >>> Signed-off-by: Md Sadre Alam <mdalam at codeaurora.org>
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