On 09/04/2018 12:00 PM, Ulf Hansson wrote:
On 1 August 2018 at 11:36, Ludovic Barre <ludovic.Barre@xxxxxx> wrote:
From: Ludovic Barre <ludovic.barre@xxxxxx>
This patch series prepares and adds callbacks for dma transfert at
mmci_host_ops. This series is composed of 3 parts:
-Internalize specific needs of legacy dmaengine.
-Create and setup dma_priv pointer
-Create generic callbacks which share some features
(like cookie...) and call specific needs
I have now reviewed part of this series and provided you with some
comments, but will stop at this point.
thanks for your review
Overall, the comments are about renaming and picking better function
names. Those comments should be easy to address in a new version.
yes, there is no problem for the naming, I will change following your
recommendations.
However, the other more important point is the number of variant
callbacks you are adding. It's of course a balance to pick the right
level, to get both flexibility but also to avoid open coding. In the
end we don't want to get too many callbacks, but then it's better to
share common mmci code for variants, through mmci.h.
Finally, I would like to see a patch on top adding the support for the
new ST variant, so I can see how the callbacks and changes really are
being used. Can you please add that?
yes, I prepare a patch with sdmmc variant to show how callbacks are used.
About comment on patch 07/14:
> So, having callbacks for dealing with dma_map|unmap() kind of
> operations, becomes rather fine-grained and not very flexible.
> Instead, what do you think of allowing the variant init function to
> dynamically assign the ->pre_req() and the ->post_req() callbacks in
> the struct mmc_host_ops. Common mmci functions to manage these
> operations can instead be shared via mmci.h and called by the
> variants.
I think we have the same goal or idea, regroup the common needs to avoid
too much specific drift.
I will try to describe the functions which are commons and the link to
specific mmci_host_ops callbacks.
(I use function names of this series, but it's just for this example)
commons function used by mmci core:
-mmci_pre_request:
check data and cookie, call common mmci_validate_data
and mmci_prepare_data.
-mmci_post_request:
check data and cookie then call common mmci_unprepare_data
-mmci_validate_data:
check the common constraint of variants, call specific
validate_data if defined.
-mmci_prepare_data:
setup common next cookie, call specific prepare data if defined
-mmci_unprepare_data:
clear the common cookie, call specific unprepare data if defined
-mmci_get_next_data:
check cookie, call specific get_next_data if defined
-mmci_dma_setup:
initialize common next_cookie, call specific dma_setup if defined
-mmci_dma_release
just call dma_release if defined
-mmci_dma_start
call common prepare data if not yet done (by next)
call specific dma_start
write common registers to start transfer and setup mmci mask
-mmci_dma_finalize:
just call dma_finalize if defined
-mmci_dma_error
just call dma_error if defined
mmci_host_ops specific:
struct mmci_host_ops
validate_data: could be use to check specific constraint of variant.
sdmmc has constraints on base & size for each element
excepted the last element which has no constraint on
size.
prepare_data: specific needs to prepare current or next data request.
mmci: dma_map_sg on channel, use dmaengine api
"dmaengine_prep_slave_sg" to queue a transfer
sdmmc: dma_map_sg on sdmmc device and prepare the link
list of internal dma
unprepare_data: specific needs to unprepare the data of request
mmci: dma_unmap_sg on channel, use dmaengine api to
terminate transfert.
sdmmc: just unmap on sdmmc device.
get_next_data: manage specific needs to move on next data
mmci: get next dmaengine descriptor and channel
sdmmc: today, nothing
dma_setup: setup specific need if you use a Direct Memory Access
mmci: use dmaengine api to request slave channel.
sdmmc: alloc memory for link list, and define specific
mmc->max_segs and mmc->max_seg_size.
dma_release: release specific resource if you use a Direct Memory
access.
mmci: use dmaengine api to release channel
sdmmc: nothing
dma_start: set specific needs to start dma request
mmci: use dmaengine api to submit and pending a dma
transfert.
sdmmc: set specific sdmmc registers to start an internal
dma transfert
dma_finalize: set specific needs to finalize a request
mmci: specific check on fifo status and
channel/descriptor management.
sdmmc: just clear a specific register of sdmmc
dma_error: specific error management.
mmci: dmaengine api to terminate a transfer
sdmmc: nothing
BR
Ludo
This patch series must be applied on top of
"mmc: mmci: Add and implement a ->dma_setup() callback for qcom dml"
Ludovic Barre (14):
mmc: mmci: fix qcom dma issue during mmci init with new dma_setup
callback
mmc: mmci: internalize dma map/unmap into mmci dma functions
mmc: mmci: internalize dma_inprogress into mmci dma functions
mmc: mmci: introduce dma_priv pointer to mmci_host
mmc: mmci: move mmci next cookie to mci host
mmc: mmci: merge prepare data functions
mmc: mmci: add prepare/unprepare_data callbacks
mmc: mmci: add get_next_data callback
mmc: mmci: modify dma_setup callback
mmc: mmci: add dma_release callback
mmc: mmci: add dma_start callback
mmc: mmci: add dma_finalize callback
mmc: mmci: add dma_error callback
mmc: mmci: add validate_data callback
drivers/mmc/host/mmci.c | 458 ++++++++++++++++++++++++---------------
drivers/mmc/host/mmci.h | 45 ++--
drivers/mmc/host/mmci_qcom_dml.c | 15 +-
3 files changed, 322 insertions(+), 196 deletions(-)
--
2.7.4
Kind regards
Uffe
