Merge branch 'mailbox-devel' of git://git.linaro.org/landing-teams/working/fujitsu/integration

Pull mailbox framework updates from Jassi Brar.

* 'mailbox-devel' of git://git.linaro.org/landing-teams/working/fujitsu/integration:
  Mailbox: Add support for Platform Communication Channel
  mailbox/omap: adapt to the new mailbox framework
  mailbox: add tx_prepare client callback
  mailbox: Don't unnecessarily re-arm the polling timer

Documentation/devicetree/bindings/mailbox/omap-mailbox.txt

@@ -43,6 +43,9 @@ Required properties:
 			device. The format is dependent on which interrupt
 			controller the OMAP device uses
 - ti,hwmods:		Name of the hwmod associated with the mailbox
+- #mbox-cells:		Common mailbox binding property to identify the number
+			of cells required for the mailbox specifier. Should be
+			1
 - ti,mbox-num-users:	Number of targets (processor devices) that the mailbox
 			device can interrupt
 - ti,mbox-num-fifos:	Number of h/w fifo queues within the mailbox IP block
@@ -72,6 +75,18 @@ data that represent the following:
     Cell #3 (usr_id)  - mailbox user id for identifying the interrupt line
                         associated with generating a tx/rx fifo interrupt.
 
+Mailbox Users:
+==============
+A device needing to communicate with a target processor device should specify
+them using the common mailbox binding properties, "mboxes" and the optional
+"mbox-names" (please see Documentation/devicetree/bindings/mailbox/mailbox.txt
+for details). Each value of the mboxes property should contain a phandle to the
+mailbox controller device node and an args specifier that will be the phandle to
+the intended sub-mailbox child node to be used for communication. The equivalent
+"mbox-names" property value can be used to give a name to the communication channel
+to be used by the client user.
+
+
 Example:
 --------
 
@@ -81,6 +96,7 @@ mailbox: mailbox@4a0f4000 {
 	reg = <0x4a0f4000 0x200>;
 	interrupts = <GIC_SPI 26 IRQ_TYPE_LEVEL_HIGH>;
 	ti,hwmods = "mailbox";
+	#mbox-cells = <1>;
 	ti,mbox-num-users = <3>;
 	ti,mbox-num-fifos = <8>;
 	mbox_ipu: mbox_ipu {
@@ -93,12 +109,19 @@ mailbox: mailbox@4a0f4000 {
 	};
 };
 
+dsp {
+	...
+	mboxes = <&mailbox &mbox_dsp>;
+	...
+};
+
 /* AM33xx */
 mailbox: mailbox@480C8000 {
 	compatible = "ti,omap4-mailbox";
 	reg = <0x480C8000 0x200>;
 	interrupts = <77>;
 	ti,hwmods = "mailbox";
+	#mbox-cells = <1>;
 	ti,mbox-num-users = <4>;
 	ti,mbox-num-fifos = <8>;
 	mbox_wkupm3: wkup_m3 {

drivers/mailbox/Kconfig

@@ -33,4 +33,16 @@ config OMAP_MBOX_KFIFO_SIZE
 	  Specify the default size of mailbox's kfifo buffers (bytes).
 	  This can also be changed at runtime (via the mbox_kfifo_size
 	  module parameter).
+
+config PCC
+	bool "Platform Communication Channel Driver"
+	depends on ACPI
+	help
+	  ACPI 5.0+ spec defines a generic mode of communication
+	  between the OS and a platform such as the BMC. This medium
+	  (PCC) is typically used by CPPC (ACPI CPU Performance management),
+	  RAS (ACPI reliability protocol) and MPST (ACPI Memory power
+	  states). Select this driver if your platform implements the
+	  PCC clients mentioned above.
+
 endif

drivers/mailbox/Makefile

@@ -5,3 +5,5 @@ obj-$(CONFIG_MAILBOX)		+= mailbox.o
 obj-$(CONFIG_PL320_MBOX)	+= pl320-ipc.o
 
 obj-$(CONFIG_OMAP2PLUS_MBOX)	+= omap-mailbox.o
+
+obj-$(CONFIG_PCC)		+= pcc.o

drivers/mailbox/mailbox.c

@@ -21,13 +21,13 @@
 #include <linux/mailbox_client.h>
 #include <linux/mailbox_controller.h>
 
-#define TXDONE_BY_IRQ	BIT(0) /* controller has remote RTR irq */
-#define TXDONE_BY_POLL	BIT(1) /* controller can read status of last TX */
-#define TXDONE_BY_ACK	BIT(2) /* S/W ACK recevied by Client ticks the TX */
+#include "mailbox.h"
 
 static LIST_HEAD(mbox_cons);
 static DEFINE_MUTEX(con_mutex);
 
+static void poll_txdone(unsigned long data);
+
 static int add_to_rbuf(struct mbox_chan *chan, void *mssg)
 {
 	int idx;
@@ -60,7 +60,7 @@ static void msg_submit(struct mbox_chan *chan)
 	unsigned count, idx;
 	unsigned long flags;
 	void *data;
-	int err;
+	int err = -EBUSY;
 
 	spin_lock_irqsave(&chan->lock, flags);
 
@@ -76,6 +76,8 @@ static void msg_submit(struct mbox_chan *chan)
 
 	data = chan->msg_data[idx];
 
+	if (chan->cl->tx_prepare)
+		chan->cl->tx_prepare(chan->cl, data);
 	/* Try to submit a message to the MBOX controller */
 	err = chan->mbox->ops->send_data(chan, data);
 	if (!err) {
@@ -84,6 +86,9 @@ static void msg_submit(struct mbox_chan *chan)
 	}
 exit:
 	spin_unlock_irqrestore(&chan->lock, flags);
+
+	if (!err && chan->txdone_method == TXDONE_BY_POLL)
+		poll_txdone((unsigned long)chan->mbox);
 }
 
 static void tx_tick(struct mbox_chan *chan, int r)
@@ -117,10 +122,11 @@ static void poll_txdone(unsigned long data)
 		struct mbox_chan *chan = &mbox->chans[i];
 
 		if (chan->active_req && chan->cl) {
-			resched = true;
 			txdone = chan->mbox->ops->last_tx_done(chan);
 			if (txdone)
 				tx_tick(chan, 0);
+			else
+				resched = true;
 		}
 	}
 
@@ -252,9 +258,6 @@ int mbox_send_message(struct mbox_chan *chan, void *mssg)
 
 	msg_submit(chan);
 
-	if (chan->txdone_method	== TXDONE_BY_POLL)
-		poll_txdone((unsigned long)chan->mbox);
-
 	if (chan->cl->tx_block && chan->active_req) {
 		unsigned long wait;
 		int ret;

drivers/mailbox/mailbox.h

+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef __MAILBOX_H
+#define __MAILBOX_H
+
+#define TXDONE_BY_IRQ	BIT(0) /* controller has remote RTR irq */
+#define TXDONE_BY_POLL	BIT(1) /* controller can read status of last TX */
+#define TXDONE_BY_ACK	BIT(2) /* S/W ACK recevied by Client ticks the TX */
+
+#endif /* __MAILBOX_H */

drivers/remoteproc/omap_remoteproc.c

@@ -27,6 +27,7 @@
 #include <linux/platform_device.h>
 #include <linux/dma-mapping.h>
 #include <linux/remoteproc.h>
+#include <linux/mailbox_client.h>
 #include <linux/omap-mailbox.h>
 
 #include <linux/platform_data/remoteproc-omap.h>
@@ -36,20 +37,19 @@
 
 /**
  * struct omap_rproc - omap remote processor state
- * @mbox: omap mailbox handle
- * @nb: notifier block that will be invoked on inbound mailbox messages
+ * @mbox: mailbox channel handle
+ * @client: mailbox client to request the mailbox channel
  * @rproc: rproc handle
  */
 struct omap_rproc {
-	struct omap_mbox *mbox;
-	struct notifier_block nb;
+	struct mbox_chan *mbox;
+	struct mbox_client client;
 	struct rproc *rproc;
 };
 
 /**
  * omap_rproc_mbox_callback() - inbound mailbox message handler
- * @this: notifier block
- * @index: unused
+ * @client: mailbox client pointer used for requesting the mailbox channel
  * @data: mailbox payload
  *
  * This handler is invoked by omap's mailbox driver whenever a mailbox
@@ -61,13 +61,13 @@ struct omap_rproc {
  * that indicates different events. Those values are deliberately very
  * big so they don't coincide with virtqueue indices.
  */
-static int omap_rproc_mbox_callback(struct notifier_block *this,
-					unsigned long index, void *data)
+static void omap_rproc_mbox_callback(struct mbox_client *client, void *data)
 {
-	mbox_msg_t msg = (mbox_msg_t) data;
-	struct omap_rproc *oproc = container_of(this, struct omap_rproc, nb);
+	struct omap_rproc *oproc = container_of(client, struct omap_rproc,
+						client);
 	struct device *dev = oproc->rproc->dev.parent;
 	const char *name = oproc->rproc->name;
+	u32 msg = (u32)data;
 
 	dev_dbg(dev, "mbox msg: 0x%x\n", msg);
 
@@ -84,8 +84,6 @@ static int omap_rproc_mbox_callback(struct notifier_block *this,
 		if (rproc_vq_interrupt(oproc->rproc, msg) == IRQ_NONE)
 			dev_dbg(dev, "no message was found in vqid %d\n", msg);
 	}
-
-	return NOTIFY_DONE;
 }
 
 /* kick a virtqueue */
@@ -96,8 +94,8 @@ static void omap_rproc_kick(struct rproc *rproc, int vqid)
 	int ret;
 
 	/* send the index of the triggered virtqueue in the mailbox payload */
-	ret = omap_mbox_msg_send(oproc->mbox, vqid);
-	if (ret)
+	ret = mbox_send_message(oproc->mbox, (void *)vqid);
+	if (ret < 0)
 		dev_err(dev, "omap_mbox_msg_send failed: %d\n", ret);
 }
 
@@ -115,17 +113,22 @@ static int omap_rproc_start(struct rproc *rproc)
 	struct platform_device *pdev = to_platform_device(dev);
 	struct omap_rproc_pdata *pdata = pdev->dev.platform_data;
 	int ret;
+	struct mbox_client *client = &oproc->client;
 
 	if (pdata->set_bootaddr)
 		pdata->set_bootaddr(rproc->bootaddr);
 
-	oproc->nb.notifier_call = omap_rproc_mbox_callback;
+	client->dev = dev;
+	client->tx_done = NULL;
+	client->rx_callback = omap_rproc_mbox_callback;
+	client->tx_block = false;
+	client->knows_txdone = false;
 
-	/* every omap rproc is assigned a mailbox instance for messaging */
-	oproc->mbox = omap_mbox_get(pdata->mbox_name, &oproc->nb);
+	oproc->mbox = omap_mbox_request_channel(client, pdata->mbox_name);
 	if (IS_ERR(oproc->mbox)) {
-		ret = PTR_ERR(oproc->mbox);
-		dev_err(dev, "omap_mbox_get failed: %d\n", ret);
+		ret = -EBUSY;
+		dev_err(dev, "mbox_request_channel failed: %ld\n",
+			PTR_ERR(oproc->mbox));
 		return ret;
 	}
 
@@ -136,9 +139,9 @@ static int omap_rproc_start(struct rproc *rproc)
 	 * Note that the reply will _not_ arrive immediately: this message
 	 * will wait in the mailbox fifo until the remote processor is booted.
 	 */
-	ret = omap_mbox_msg_send(oproc->mbox, RP_MBOX_ECHO_REQUEST);
-	if (ret) {
-		dev_err(dev, "omap_mbox_get failed: %d\n", ret);
+	ret = mbox_send_message(oproc->mbox, (void *)RP_MBOX_ECHO_REQUEST);
+	if (ret < 0) {
+		dev_err(dev, "mbox_send_message failed: %d\n", ret);
 		goto put_mbox;
 	}
 
@@ -151,7 +154,7 @@ static int omap_rproc_start(struct rproc *rproc)
 	return 0;
 
 put_mbox:
-	omap_mbox_put(oproc->mbox, &oproc->nb);
+	mbox_free_channel(oproc->mbox);
 	return ret;
 }
 
@@ -168,7 +171,7 @@ static int omap_rproc_stop(struct rproc *rproc)
 	if (ret)
 		return ret;
 
-	omap_mbox_put(oproc->mbox, &oproc->nb);
+	mbox_free_channel(oproc->mbox);
 
 	return 0;
 }

include/linux/mailbox_client.h

@@ -25,6 +25,8 @@ struct mbox_chan;
  *			if the client receives some ACK packet for transmission.
  *			Unused if the controller already has TX_Done/RTR IRQ.
  * @rx_callback:	Atomic callback to provide client the data received
+ * @tx_prepare: 	Atomic callback to ask client to prepare the payload
+ *			before initiating the transmission if required.
  * @tx_done:		Atomic callback to tell client of data transmission
  */
 struct mbox_client {
@@ -34,6 +36,7 @@ struct mbox_client {
 	bool knows_txdone;
 
 	void (*rx_callback)(struct mbox_client *cl, void *mssg);
+	void (*tx_prepare)(struct mbox_client *cl, void *mssg);
 	void (*tx_done)(struct mbox_client *cl, void *mssg, int r);
 };
 

include/linux/omap-mailbox.h

@@ -10,20 +10,20 @@
 #define OMAP_MAILBOX_H
 
 typedef u32 mbox_msg_t;
-struct omap_mbox;
 
 typedef int __bitwise omap_mbox_irq_t;
 #define IRQ_TX ((__force omap_mbox_irq_t) 1)
 #define IRQ_RX ((__force omap_mbox_irq_t) 2)
 
-int omap_mbox_msg_send(struct omap_mbox *, mbox_msg_t msg);
+struct mbox_chan;
+struct mbox_client;
 
-struct omap_mbox *omap_mbox_get(const char *, struct notifier_block *nb);
-void omap_mbox_put(struct omap_mbox *mbox, struct notifier_block *nb);
+struct mbox_chan *omap_mbox_request_channel(struct mbox_client *cl,
+					    const char *chan_name);
 
-void omap_mbox_save_ctx(struct omap_mbox *mbox);
-void omap_mbox_restore_ctx(struct omap_mbox *mbox);
-void omap_mbox_enable_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq);
-void omap_mbox_disable_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq);
+void omap_mbox_save_ctx(struct mbox_chan *chan);
+void omap_mbox_restore_ctx(struct mbox_chan *chan);
+void omap_mbox_enable_irq(struct mbox_chan *chan, omap_mbox_irq_t irq);
+void omap_mbox_disable_irq(struct mbox_chan *chan, omap_mbox_irq_t irq);
 
 #endif /* OMAP_MAILBOX_H */