On Wed, Nov 28, 2018 at 3:54 AM Thierry Reding <thierry.reding@xxxxxxxxx> wrote: > > From: Thierry Reding <treding@xxxxxxxxxx> > > Hi everyone, > > this is a reworked version of Mikko's earlier proposal[0]. I've reworked > the TCU driver itself so that it relies less on global variables as well > as added a Kconfig option to allow the console support to be selected. I > also fixed a couple of issues that manifested themselves as I was moving > towards the IRQ driven mode (TCU was passing a pointer to a local > variable which was getting stored in the mailbox's ring buffer and the > data pointed at was becoming stale by the time the mailbox got around to > dequeue it). > > The biggest bulk of the changes is in the mailbox driver. This series > addresses all of Jassi's comments from back at the time. One notable > additional change is that shared mailboxes are now interrupt driven, > which removes the need for polling mode. > > Unfortunately there is still an issue because the TCU uses the mailbox > in atomic context for both TTY and console modes, so we get a sleeping- > while-atomic BUG when using mbox_client->tx_block = true in order to > rate-limit mbox_send_message(). In order to work around this, I added a > new mbox_flush() API that will allow flushing the mailbox in atomic > context by using the mailbox controller's implementation of ->flush(). > For Tegra HSP shared mailboxes this is done by spinning on the shared > mailbox register until the receiver has marked the mailbox as empty. I > have been running this locally for a couple of days now and it works > perfectly. > > Furthermore this series incorporates Mikko's work in progress on > splitting up the mailbox controllers and allowing multiple controllers > to match on the same device tree node during mbox_request_channel(). > > The new mbox_flush() API introduces a build-time dependency between the > TCU driver and the mailbox framework, so patches 1-9 would need to go > through one tree. Patch 9 was already acked by Greg, so I would suggest > that Jassi pick up the first 9 patches and I pick up patches 10-12 into > the Tegra tree. > Picked the first 8. The patch-9 is tcu serial driver and should go via tty. -Jassi
