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2015-10-23mailbox/omap: Add ti,mbox-send-noirq quirk to fix AM33xx CPU IdleDave Gerlach1-0/+8
The mailbox framework controls the transmission queue and requires either its controller implementations or clients to run the state machine for the Tx queue. The OMAP mailbox controller uses a Tx-ready interrupt as the equivalent of a Tx-done interrupt to run this Tx queue state-machine. The WkupM3 processor on AM33xx and AM43xx SoCs is used to offload certain PM tasks, like doing the necessary operations for Device PM suspend/resume or for entering lower c-states during cpuidle. The CPUIdle on AM33xx requires the messages to be sent without having to trigger the Tx-ready interrupts, as the interrupt would immediately terminate the CPUIdle operation. Support for this has been added by introducing a DT quirk, "ti,mbox-send-noirq" and using it to modify the normal OMAP mailbox controller behavior on the sub-mailboxes used to communicate with the WkupM3 remote processor. This also requires the wkup_m3_ipc driver to adjust its mailbox usage logic to run the Tx state machine. NOTE: - AM43xx does not communicate with WkupM3 for CPU Idle, so is not affected by this behavior. But, it uses the same IPC driver for PM suspend/resume functionality, so requires the quirk as well, because of changes to the common wkup_m3_ipc driver. Signed-off-by: Dave Gerlach <d-gerlach@ti.com> [s-anna@ti.com: revise logic and update comments/patch description] Signed-off-by: Suman Anna <s-anna@ti.com> Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>
2014-11-27mailbox/omap: adapt to the new mailbox frameworkSuman Anna1-0/+23
The OMAP mailbox driver and its existing clients (remoteproc for OMAP4+) are adapted to use the generic mailbox framework. The main changes for the adaptation are: - The tasklet used for Tx is replaced with the state machine from the generic mailbox framework. The workqueue used for processing the received messages stays intact for minimizing the effects on the OMAP mailbox clients. - The existing exported client API, omap_mbox_get, omap_mbox_put and omap_mbox_send_msg are deleted, as the framework provides equivalent functionality. A OMAP-specific omap_mbox_request_channel is added though to support non-DT way of requesting mailboxes. - The OMAP mailbox driver is integrated with the mailbox framework through the proper implementations of mbox_chan_ops, except for .last_tx_done and .peek_data. The OMAP mailbox driver does not need these ops, as it is completely interrupt driven. - The OMAP mailbox driver uses a custom of_xlate controller ops that allows phandles for the pargs specifier instead of indexing to avoid any channel registration order dependencies. - The new framework does not support multiple clients operating on a single channel, so the reference counting logic is simplified. - The remoteproc driver (current client) is adapted to use the new API. The notifier callbacks used within this client is replaced with the regular callbacks from the newer framework. - The exported OMAP mailbox API are limited to omap_mbox_save_ctx, omap_mbox_restore_ctx, omap_mbox_enable_irq & omap_mbox_disable_irq, with the signature modified to take in the new mbox_chan handle instead of the OMAP specific omap_mbox handle. The first 2 will be removed when the OMAP mailbox driver is adapted to runtime_pm. The other exported API omap_mbox_request_channel will be removed once existing legacy users are converted to DT. Signed-off-by: Suman Anna <s-anna@ti.com> Cc: Ohad Ben-Cohen <ohad@wizery.com> Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>
2014-09-11Documentation: dt: add omap mailbox bindingsSuman Anna1-0/+108
Add the device tree bindings document for OMAP2+ mailbox. Cc: Rob Herring <robh+dt@kernel.org> Cc: Pawel Moll <pawel.moll@arm.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Ian Campbell <ijc+devicetree@hellion.org.uk> Cc: Kumar Gala <galak@codeaurora.org> Signed-off-by: Suman Anna <s-anna@ti.com> Signed-off-by: Tony Lindgren <tony@atomide.com>