Hi Kalle, Stephen, On Fri, Aug 27, 2021 at 07:24:49PM +0300, Kalle Valo wrote: > Greg KH <greg@xxxxxxxxx> writes: > [...] > I'll explain that in detail below. But do note that I'm not familiar > with the MHI subsystem and the MHI folks really should look at this in > detail to make sure no new bugs are introduced! I did the conflict > resolution myself and at least ath11k works after this resolution. > I wanted to fix this thing before breaking for vacation but ended up responding to it in the middle. > In my test merge I first used Linus' tree as of today as the baseline. > I first merged net-next and it went without conflicts. After that I > merged char-misc-next and got conflicts in two files: > [...] > diff --git a/drivers/bus/mhi/core/main.c b/drivers/bus/mhi/core/main.c > index 88dba230f406..b15c5bc37dd4 100644 > --- a/drivers/bus/mhi/core/main.c > +++ b/drivers/bus/mhi/core/main.c > @@ -1455,9 +1455,6 @@ int mhi_prepare_channel(struct mhi_controller *mhi_cntrl, > if (ret) > goto error_pm_state; > > - if (mhi_chan->dir == DMA_FROM_DEVICE) > - mhi_chan->pre_alloc = !!(flags & MHI_CH_INBOUND_ALLOC_BUFS); > - > /* Pre-allocate buffer for xfer ring */ > if (mhi_chan->pre_alloc) { > int nr_el = get_nr_avail_ring_elements(mhi_cntrl, > > Greg, does this help? Stephen, do you have any advice how to handle > this? > Sorry, this fix won't work. I've done the conflict resolution in mhi-conflict-fix [1] branch for reference. The MHI diffs are below: diff --git a/drivers/bus/mhi/core/main.c b/drivers/bus/mhi/core/main.c index fc9196f11cb7d..c01ec2fef02ce 100644 --- a/drivers/bus/mhi/core/main.c +++ b/drivers/bus/mhi/core/main.c @@ -193,7 +193,7 @@ int mhi_map_single_no_bb(struct mhi_controller *mhi_cntrl, int mhi_map_single_use_bb(struct mhi_controller *mhi_cntrl, struct mhi_buf_info *buf_info) { - void *buf = mhi_alloc_coherent(mhi_cntrl, buf_info->len, + void *buf = dma_alloc_coherent(mhi_cntrl->cntrl_dev, buf_info->len, &buf_info->p_addr, GFP_ATOMIC); if (!buf) @@ -220,8 +220,8 @@ void mhi_unmap_single_use_bb(struct mhi_controller *mhi_cntrl, if (buf_info->dir == DMA_FROM_DEVICE) memcpy(buf_info->v_addr, buf_info->bb_addr, buf_info->len); - mhi_free_coherent(mhi_cntrl, buf_info->len, buf_info->bb_addr, - buf_info->p_addr); + dma_free_coherent(mhi_cntrl->cntrl_dev, buf_info->len, + buf_info->bb_addr, buf_info->p_addr); } static int get_nr_avail_ring_elements(struct mhi_controller *mhi_cntrl, @@ -1430,7 +1430,7 @@ exit_unprepare_channel: } int mhi_prepare_channel(struct mhi_controller *mhi_cntrl, - struct mhi_chan *mhi_chan) + struct mhi_chan *mhi_chan, unsigned int flags) { int ret = 0; struct device *dev = &mhi_chan->mhi_dev->dev; @@ -1455,6 +1455,9 @@ int mhi_prepare_channel(struct mhi_controller *mhi_cntrl, if (ret) goto error_pm_state; + if (mhi_chan->dir == DMA_FROM_DEVICE) + mhi_chan->pre_alloc = !!(flags & MHI_CH_INBOUND_ALLOC_BUFS); + /* Pre-allocate buffer for xfer ring */ if (mhi_chan->pre_alloc) { int nr_el = get_nr_avail_ring_elements(mhi_cntrl, @@ -1610,7 +1613,7 @@ void mhi_reset_chan(struct mhi_controller *mhi_cntrl, struct mhi_chan *mhi_chan) } /* Move channel to start state */ -int mhi_prepare_for_transfer(struct mhi_device *mhi_dev) +int mhi_prepare_for_transfer(struct mhi_device *mhi_dev, unsigned int flags) { int ret, dir; struct mhi_controller *mhi_cntrl = mhi_dev->mhi_cntrl; @@ -1621,7 +1624,7 @@ int mhi_prepare_for_transfer(struct mhi_device *mhi_dev) if (!mhi_chan) continue; - ret = mhi_prepare_channel(mhi_cntrl, mhi_chan); + ret = mhi_prepare_channel(mhi_cntrl, mhi_chan, flags); if (ret) goto error_open_chan; } diff --git a/net/qrtr/mhi.c b/net/qrtr/mhi.c index fa611678af052..29b4fa3b72abf 100644 --- a/net/qrtr/mhi.c +++ b/net/qrtr/mhi.c @@ -79,7 +79,7 @@ static int qcom_mhi_qrtr_probe(struct mhi_device *mhi_dev, int rc; /* start channels */ - rc = mhi_prepare_for_transfer(mhi_dev); + rc = mhi_prepare_for_transfer(mhi_dev, MHI_CH_INBOUND_ALLOC_BUFS); if (rc) return rc; But this can be avoided if the below commit is reverted in char-misc-next: 0092a1e3f763 ("bus: mhi: Add inbound buffers allocation flag") I won't have any objection to that (the original patch can land in v5.16) and if Greg prefers that, I can send a quick revert patch. Please let me know! NOTE: I haven't tested these two solutions as I'm still on vacation. Kalle, could you please test them to make sure I haven't missed anything? Thanks, Mani [1] https://git.kernel.org/pub/scm/linux/kernel/git/mani/mhi.git/log/?h=mhi-conflict-fix > -- > https://patchwork.kernel.org/project/linux-wireless/list/ > > https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches