Messages in this thread | | | Subject | Re: [PATCH] nvme: Add support for Apple 2018+ models | From | Benjamin Herrenschmidt <> | Date | Mon, 15 Jul 2019 18:43:25 +1000 |
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On Mon, 2019-07-15 at 10:10 +0200, Christoph Hellwig wrote: > > + /* > > + * Apple 2018 and latter variant has a few issues > > + */ > > + NVME_QUIRK_APPLE_2018 = (1 << 10), > > We try to have quirks for the actual issue, so this should be one quirk > for the irq vectors issues, and another for the sq entry size. Note that > NVMe actually has the concept of an I/O queue entry size (IOSQES in the > Cc register based on values reported in the SQES field in Identify > Controller. Do these controllers report anything interesting there?
Ah good to know, I'll dig.
> At the very least I'd make all the terminology based on that and then > just treat the Apple controllers as a buggy implementation of that model.
Yup, sounds good. I'll poke around tomorrow.
> Btw, are there open source darwin NVMe driver that could explain this > mess a little better?
You wish...
> > @@ -504,8 +505,11 @@ static inline void nvme_write_sq_db(struct nvme_queue *nvmeq, bool write_sq) > > static void nvme_submit_cmd(struct nvme_queue *nvmeq, struct nvme_command *cmd, > > bool write_sq) > > { > > + u16 sq_actual_pos; > > + > > spin_lock(&nvmeq->sq_lock); > > - memcpy(&nvmeq->sq_cmds[nvmeq->sq_tail], cmd, sizeof(*cmd)); > > + sq_actual_pos = nvmeq->sq_tail << nvmeq->sq_extra_shift; > > + memcpy(&nvmeq->sq_cmds[sq_actual_pos], cmd, sizeof(*cmd)); > > This is a little too magic. I think we'd better off making sq_cmds > a void array and use manual indexing, at least that makes it very > obvious what is going on.
Ok. That's plan B as I described in the message. There's an advantage to do that, it merges the indexing shift and the quirk shift into one.
I'll look into it & respin
> > - nvmeq->sq_cmds, SQ_SIZE(nvmeq->q_depth)); > > + nvmeq->sq_cmds, SQ_SIZE(nvmeq)); > > Btw, chaning SQ_SIZE to take the queue seems like something that should > be split into a prep patch, making the main change a lot smaller.
Sure. Will do.
> > - if (!polled) > > + if (!polled) { > > + > > + /* > > + * On Apple 2018 or later implementations, only vector 0 is accepted > > Please fix the > 80 char line.
Ok.
Thanks for the review.
Cheers, Ben.
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