remoteproc/omap: add a remoteproc driver for OMAP4

Add a remoteproc driver for OMAP4, so we can boot the dual-M3 and
and DSP subsystems.

Use the omap_device_* API to control the hardware state, and utilize
the OMAP mailbox to interrupt the remote processor when a new message
is pending (the mailbox payload is used to tell it which virtqueue was
the message placed in).

Conversely, when an inbound mailbox message arrives, tell the remoteproc
core which virtqueue is triggered.

Later we will also use the mailbox payload to signal omap-specific
events like remote crashes (which will be used to trigger remoteproc
recovery) and power management transitions. At that point we will also
extend the remoteproc core to support this.

Based on (but now quite far from) work done by Fernando Guzman Lugo
<fernando.lugo@ti.com> and Hari Kanigeri <h-kanigeri2@ti.com>.

Designed with Brian Swetland <swetland@google.com>.

Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Cc: Brian Swetland <swetland@google.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Greg KH <greg@kroah.com>
Cc: Stephen Boyd <sboyd@codeaurora.org>

1 files changed, 69 insertions, 0 deletions

diff --git a/drivers/remoteproc/omap_remoteproc.h b/drivers/remoteproc/omap_remoteproc.h
new file mode 100644
index 000000000000..f6d2036d383d
--- /dev/null
+++ b/drivers/remoteproc/omap_remoteproc.h
@@ -0,0 +1,69 @@
+/*
+ * Remote processor messaging
+ *
+ * Copyright (C) 2011 Texas Instruments, Inc.
+ * Copyright (C) 2011 Google, Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * * Redistributions of source code must retain the above copyright
+ *   notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above copyright
+ *   notice, this list of conditions and the following disclaimer in
+ *   the documentation and/or other materials provided with the
+ *   distribution.
+ * * Neither the name Texas Instruments nor the names of its
+ *   contributors may be used to endorse or promote products derived
+ *   from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef _OMAP_RPMSG_H
+#define _OMAP_RPMSG_H
+
+/*
+ * enum - Predefined Mailbox Messages
+ *
+ * @RP_MBOX_READY: informs the M3's that we're up and running. this is
+ * part of the init sequence sent that the M3 expects to see immediately
+ * after it is booted.
+ *
+ * @RP_MBOX_PENDING_MSG: informs the receiver that there is an inbound
+ * message waiting in its own receive-side vring. please note that currently
+ * this message is optional: alternatively, one can explicitly send the index
+ * of the triggered virtqueue itself. the preferred approach will be decided
+ * as we progress and experiment with those two different approaches.
+ *
+ * @RP_MBOX_CRASH: this message is sent if BIOS crashes
+ *
+ * @RP_MBOX_ECHO_REQUEST: a mailbox-level "ping" message.
+ *
+ * @RP_MBOX_ECHO_REPLY: a mailbox-level reply to a "ping"
+ *
+ * @RP_MBOX_ABORT_REQUEST: a "please crash" request, used for testing the
+ * recovery mechanism (to some extent).
+ */
+enum omap_rp_mbox_messages {
+	RP_MBOX_READY		= 0xFFFFFF00,
+	RP_MBOX_PENDING_MSG	= 0xFFFFFF01,
+	RP_MBOX_CRASH		= 0xFFFFFF02,
+	RP_MBOX_ECHO_REQUEST	= 0xFFFFFF03,
+	RP_MBOX_ECHO_REPLY	= 0xFFFFFF04,
+	RP_MBOX_ABORT_REQUEST	= 0xFFFFFF05,
+};
+
+#endif /* _OMAP_RPMSG_H */