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-rw-r--r--drivers/mailbox/Kconfig12
-rw-r--r--drivers/mailbox/Makefile6
-rw-r--r--drivers/mailbox/mailbox.c468
-rw-r--r--drivers/mailbox/mailbox.h14
-rw-r--r--drivers/mailbox/omap-mailbox.c347
-rw-r--r--drivers/mailbox/pcc.c403
-rw-r--r--drivers/mailbox/pl320-ipc.c2
7 files changed, 1102 insertions, 150 deletions
diff --git a/drivers/mailbox/Kconfig b/drivers/mailbox/Kconfig
index 9fd9c6717e0c..c04fed9eb15d 100644
--- a/drivers/mailbox/Kconfig
+++ b/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
diff --git a/drivers/mailbox/Makefile b/drivers/mailbox/Makefile
index 6d184dbcaca8..dd412c22208b 100644
--- a/drivers/mailbox/Makefile
+++ b/drivers/mailbox/Makefile
@@ -1,3 +1,9 @@
+# Generic MAILBOX API
+
+obj-$(CONFIG_MAILBOX) += mailbox.o
+
obj-$(CONFIG_PL320_MBOX) += pl320-ipc.o
obj-$(CONFIG_OMAP2PLUS_MBOX) += omap-mailbox.o
+
+obj-$(CONFIG_PCC) += pcc.o
diff --git a/drivers/mailbox/mailbox.c b/drivers/mailbox/mailbox.c
new file mode 100644
index 000000000000..59aad4d5da53
--- /dev/null
+++ b/drivers/mailbox/mailbox.c
@@ -0,0 +1,468 @@
+/*
+ * Mailbox: Common code for Mailbox controllers and users
+ *
+ * Copyright (C) 2013-2014 Linaro Ltd.
+ * Author: Jassi Brar <jassisinghbrar@gmail.com>
+ *
+ * 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.
+ */
+
+#include <linux/interrupt.h>
+#include <linux/spinlock.h>
+#include <linux/mutex.h>
+#include <linux/delay.h>
+#include <linux/slab.h>
+#include <linux/err.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/bitops.h>
+#include <linux/mailbox_client.h>
+#include <linux/mailbox_controller.h>
+
+#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;
+ unsigned long flags;
+
+ spin_lock_irqsave(&chan->lock, flags);
+
+ /* See if there is any space left */
+ if (chan->msg_count == MBOX_TX_QUEUE_LEN) {
+ spin_unlock_irqrestore(&chan->lock, flags);
+ return -ENOBUFS;
+ }
+
+ idx = chan->msg_free;
+ chan->msg_data[idx] = mssg;
+ chan->msg_count++;
+
+ if (idx == MBOX_TX_QUEUE_LEN - 1)
+ chan->msg_free = 0;
+ else
+ chan->msg_free++;
+
+ spin_unlock_irqrestore(&chan->lock, flags);
+
+ return idx;
+}
+
+static void msg_submit(struct mbox_chan *chan)
+{
+ unsigned count, idx;
+ unsigned long flags;
+ void *data;
+ int err = -EBUSY;
+
+ spin_lock_irqsave(&chan->lock, flags);
+
+ if (!chan->msg_count || chan->active_req)
+ goto exit;
+
+ count = chan->msg_count;
+ idx = chan->msg_free;
+ if (idx >= count)
+ idx -= count;
+ else
+ idx += MBOX_TX_QUEUE_LEN - count;
+
+ 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) {
+ chan->active_req = data;
+ chan->msg_count--;
+ }
+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)
+{
+ unsigned long flags;
+ void *mssg;
+
+ spin_lock_irqsave(&chan->lock, flags);
+ mssg = chan->active_req;
+ chan->active_req = NULL;
+ spin_unlock_irqrestore(&chan->lock, flags);
+
+ /* Submit next message */
+ msg_submit(chan);
+
+ /* Notify the client */
+ if (mssg && chan->cl->tx_done)
+ chan->cl->tx_done(chan->cl, mssg, r);
+
+ if (chan->cl->tx_block)
+ complete(&chan->tx_complete);
+}
+
+static void poll_txdone(unsigned long data)
+{
+ struct mbox_controller *mbox = (struct mbox_controller *)data;
+ bool txdone, resched = false;
+ int i;
+
+ for (i = 0; i < mbox->num_chans; i++) {
+ struct mbox_chan *chan = &mbox->chans[i];
+
+ if (chan->active_req && chan->cl) {
+ txdone = chan->mbox->ops->last_tx_done(chan);
+ if (txdone)
+ tx_tick(chan, 0);
+ else
+ resched = true;
+ }
+ }
+
+ if (resched)
+ mod_timer(&mbox->poll, jiffies +
+ msecs_to_jiffies(mbox->txpoll_period));
+}
+
+/**
+ * mbox_chan_received_data - A way for controller driver to push data
+ * received from remote to the upper layer.
+ * @chan: Pointer to the mailbox channel on which RX happened.
+ * @mssg: Client specific message typecasted as void *
+ *
+ * After startup and before shutdown any data received on the chan
+ * is passed on to the API via atomic mbox_chan_received_data().
+ * The controller should ACK the RX only after this call returns.
+ */
+void mbox_chan_received_data(struct mbox_chan *chan, void *mssg)
+{
+ /* No buffering the received data */
+ if (chan->cl->rx_callback)
+ chan->cl->rx_callback(chan->cl, mssg);
+}
+EXPORT_SYMBOL_GPL(mbox_chan_received_data);
+
+/**
+ * mbox_chan_txdone - A way for controller driver to notify the
+ * framework that the last TX has completed.
+ * @chan: Pointer to the mailbox chan on which TX happened.
+ * @r: Status of last TX - OK or ERROR
+ *
+ * The controller that has IRQ for TX ACK calls this atomic API
+ * to tick the TX state machine. It works only if txdone_irq
+ * is set by the controller.
+ */
+void mbox_chan_txdone(struct mbox_chan *chan, int r)
+{
+ if (unlikely(!(chan->txdone_method & TXDONE_BY_IRQ))) {
+ dev_err(chan->mbox->dev,
+ "Controller can't run the TX ticker\n");
+ return;
+ }
+
+ tx_tick(chan, r);
+}
+EXPORT_SYMBOL_GPL(mbox_chan_txdone);
+
+/**
+ * mbox_client_txdone - The way for a client to run the TX state machine.
+ * @chan: Mailbox channel assigned to this client.
+ * @r: Success status of last transmission.
+ *
+ * The client/protocol had received some 'ACK' packet and it notifies
+ * the API that the last packet was sent successfully. This only works
+ * if the controller can't sense TX-Done.
+ */
+void mbox_client_txdone(struct mbox_chan *chan, int r)
+{
+ if (unlikely(!(chan->txdone_method & TXDONE_BY_ACK))) {
+ dev_err(chan->mbox->dev, "Client can't run the TX ticker\n");
+ return;
+ }
+
+ tx_tick(chan, r);
+}
+EXPORT_SYMBOL_GPL(mbox_client_txdone);
+
+/**
+ * mbox_client_peek_data - A way for client driver to pull data
+ * received from remote by the controller.
+ * @chan: Mailbox channel assigned to this client.
+ *
+ * A poke to controller driver for any received data.
+ * The data is actually passed onto client via the
+ * mbox_chan_received_data()
+ * The call can be made from atomic context, so the controller's
+ * implementation of peek_data() must not sleep.
+ *
+ * Return: True, if controller has, and is going to push after this,
+ * some data.
+ * False, if controller doesn't have any data to be read.
+ */
+bool mbox_client_peek_data(struct mbox_chan *chan)
+{
+ if (chan->mbox->ops->peek_data)
+ return chan->mbox->ops->peek_data(chan);
+
+ return false;
+}
+EXPORT_SYMBOL_GPL(mbox_client_peek_data);
+
+/**
+ * mbox_send_message - For client to submit a message to be
+ * sent to the remote.
+ * @chan: Mailbox channel assigned to this client.
+ * @mssg: Client specific message typecasted.
+ *
+ * For client to submit data to the controller destined for a remote
+ * processor. If the client had set 'tx_block', the call will return
+ * either when the remote receives the data or when 'tx_tout' millisecs
+ * run out.
+ * In non-blocking mode, the requests are buffered by the API and a
+ * non-negative token is returned for each queued request. If the request
+ * is not queued, a negative token is returned. Upon failure or successful
+ * TX, the API calls 'tx_done' from atomic context, from which the client
+ * could submit yet another request.
+ * The pointer to message should be preserved until it is sent
+ * over the chan, i.e, tx_done() is made.
+ * This function could be called from atomic context as it simply
+ * queues the data and returns a token against the request.
+ *
+ * Return: Non-negative integer for successful submission (non-blocking mode)
+ * or transmission over chan (blocking mode).
+ * Negative value denotes failure.
+ */
+int mbox_send_message(struct mbox_chan *chan, void *mssg)
+{
+ int t;
+
+ if (!chan || !chan->cl)
+ return -EINVAL;
+
+ t = add_to_rbuf(chan, mssg);
+ if (t < 0) {
+ dev_err(chan->mbox->dev, "Try increasing MBOX_TX_QUEUE_LEN\n");
+ return t;
+ }
+
+ msg_submit(chan);
+
+ if (chan->cl->tx_block && chan->active_req) {
+ unsigned long wait;
+ int ret;
+
+ if (!chan->cl->tx_tout) /* wait forever */
+ wait = msecs_to_jiffies(3600000);
+ else
+ wait = msecs_to_jiffies(chan->cl->tx_tout);
+
+ ret = wait_for_completion_timeout(&chan->tx_complete, wait);
+ if (ret == 0) {
+ t = -EIO;
+ tx_tick(chan, -EIO);
+ }
+ }
+
+ return t;
+}
+EXPORT_SYMBOL_GPL(mbox_send_message);
+
+/**
+ * mbox_request_channel - Request a mailbox channel.
+ * @cl: Identity of the client requesting the channel.
+ * @index: Index of mailbox specifier in 'mboxes' property.
+ *
+ * The Client specifies its requirements and capabilities while asking for
+ * a mailbox channel. It can't be called from atomic context.
+ * The channel is exclusively allocated and can't be used by another
+ * client before the owner calls mbox_free_channel.
+ * After assignment, any packet received on this channel will be
+ * handed over to the client via the 'rx_callback'.
+ * The framework holds reference to the client, so the mbox_client
+ * structure shouldn't be modified until the mbox_free_channel returns.
+ *
+ * Return: Pointer to the channel assigned to the client if successful.
+ * ERR_PTR for request failure.
+ */
+struct mbox_chan *mbox_request_channel(struct mbox_client *cl, int index)
+{
+ struct device *dev = cl->dev;
+ struct mbox_controller *mbox;
+ struct of_phandle_args spec;
+ struct mbox_chan *chan;
+ unsigned long flags;
+ int ret;
+
+ if (!dev || !dev->of_node) {
+ pr_debug("%s: No owner device node\n", __func__);
+ return ERR_PTR(-ENODEV);
+ }
+
+ mutex_lock(&con_mutex);
+
+ if (of_parse_phandle_with_args(dev->of_node, "mboxes",
+ "#mbox-cells", index, &spec)) {
+ dev_dbg(dev, "%s: can't parse \"mboxes\" property\n", __func__);
+ mutex_unlock(&con_mutex);
+ return ERR_PTR(-ENODEV);
+ }
+
+ chan = NULL;
+ list_for_each_entry(mbox, &mbox_cons, node)
+ if (mbox->dev->of_node == spec.np) {
+ chan = mbox->of_xlate(mbox, &spec);
+ break;
+ }
+
+ of_node_put(spec.np);
+
+ if (!chan || chan->cl || !try_module_get(mbox->dev->driver->owner)) {
+ dev_dbg(dev, "%s: mailbox not free\n", __func__);
+ mutex_unlock(&con_mutex);
+ return ERR_PTR(-EBUSY);
+ }
+
+ spin_lock_irqsave(&chan->lock, flags);
+ chan->msg_free = 0;
+ chan->msg_count = 0;
+ chan->active_req = NULL;
+ chan->cl = cl;
+ init_completion(&chan->tx_complete);
+
+ if (chan->txdone_method == TXDONE_BY_POLL && cl->knows_txdone)
+ chan->txdone_method |= TXDONE_BY_ACK;
+
+ spin_unlock_irqrestore(&chan->lock, flags);
+
+ ret = chan->mbox->ops->startup(chan);
+ if (ret) {
+ dev_err(dev, "Unable to startup the chan (%d)\n", ret);
+ mbox_free_channel(chan);
+ chan = ERR_PTR(ret);
+ }
+
+ mutex_unlock(&con_mutex);
+ return chan;
+}
+EXPORT_SYMBOL_GPL(mbox_request_channel);
+
+/**
+ * mbox_free_channel - The client relinquishes control of a mailbox
+ * channel by this call.
+ * @chan: The mailbox channel to be freed.
+ */
+void mbox_free_channel(struct mbox_chan *chan)
+{
+ unsigned long flags;
+
+ if (!chan || !chan->cl)
+ return;
+
+ chan->mbox->ops->shutdown(chan);
+
+ /* The queued TX requests are simply aborted, no callbacks are made */
+ spin_lock_irqsave(&chan->lock, flags);
+ chan->cl = NULL;
+ chan->active_req = NULL;
+ if (chan->txdone_method == (TXDONE_BY_POLL | TXDONE_BY_ACK))
+ chan->txdone_method = TXDONE_BY_POLL;
+
+ module_put(chan->mbox->dev->driver->owner);
+ spin_unlock_irqrestore(&chan->lock, flags);
+}
+EXPORT_SYMBOL_GPL(mbox_free_channel);
+
+static struct mbox_chan *
+of_mbox_index_xlate(struct mbox_controller *mbox,
+ const struct of_phandle_args *sp)
+{
+ int ind = sp->args[0];
+
+ if (ind >= mbox->num_chans)
+ return NULL;
+
+ return &mbox->chans[ind];
+}
+
+/**
+ * mbox_controller_register - Register the mailbox controller
+ * @mbox: Pointer to the mailbox controller.
+ *
+ * The controller driver registers its communication channels
+ */
+int mbox_controller_register(struct mbox_controller *mbox)
+{
+ int i, txdone;
+
+ /* Sanity check */
+ if (!mbox || !mbox->dev || !mbox->ops || !mbox->num_chans)
+ return -EINVAL;
+
+ if (mbox->txdone_irq)
+ txdone = TXDONE_BY_IRQ;
+ else if (mbox->txdone_poll)
+ txdone = TXDONE_BY_POLL;
+ else /* It has to be ACK then */
+ txdone = TXDONE_BY_ACK;
+
+ if (txdone == TXDONE_BY_POLL) {
+ mbox->poll.function = &poll_txdone;
+ mbox->poll.data = (unsigned long)mbox;
+ init_timer(&mbox->poll);
+ }
+
+ for (i = 0; i < mbox->num_chans; i++) {
+ struct mbox_chan *chan = &mbox->chans[i];
+
+ chan->cl = NULL;
+ chan->mbox = mbox;
+ chan->txdone_method = txdone;
+ spin_lock_init(&chan->lock);
+ }
+
+ if (!mbox->of_xlate)
+ mbox->of_xlate = of_mbox_index_xlate;
+
+ mutex_lock(&con_mutex);
+ list_add_tail(&mbox->node, &mbox_cons);
+ mutex_unlock(&con_mutex);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(mbox_controller_register);
+
+/**
+ * mbox_controller_unregister - Unregister the mailbox controller
+ * @mbox: Pointer to the mailbox controller.
+ */
+void mbox_controller_unregister(struct mbox_controller *mbox)
+{
+ int i;
+
+ if (!mbox)
+ return;
+
+ mutex_lock(&con_mutex);
+
+ list_del(&mbox->node);
+
+ for (i = 0; i < mbox->num_chans; i++)
+ mbox_free_channel(&mbox->chans[i]);
+
+ if (mbox->txdone_poll)
+ del_timer_sync(&mbox->poll);
+
+ mutex_unlock(&con_mutex);
+}
+EXPORT_SYMBOL_GPL(mbox_controller_unregister);
diff --git a/drivers/mailbox/mailbox.h b/drivers/mailbox/mailbox.h
new file mode 100644
index 000000000000..456ba68513bb
--- /dev/null
+++ b/drivers/mailbox/mailbox.h
@@ -0,0 +1,14 @@
+/*
+ * 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 */
diff --git a/drivers/mailbox/omap-mailbox.c b/drivers/mailbox/omap-mailbox.c
index bcc7ee129276..0f332c178b07 100644
--- a/drivers/mailbox/omap-mailbox.c
+++ b/drivers/mailbox/omap-mailbox.c
@@ -29,13 +29,14 @@
#include <linux/slab.h>
#include <linux/kfifo.h>
#include <linux/err.h>
-#include <linux/notifier.h>
#include <linux/module.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
#include <linux/platform_data/mailbox-omap.h>
#include <linux/omap-mailbox.h>
+#include <linux/mailbox_controller.h>
+#include <linux/mailbox_client.h>
#define MAILBOX_REVISION 0x000
#define MAILBOX_MESSAGE(m) (0x040 + 4 * (m))
@@ -80,7 +81,6 @@ struct omap_mbox_queue {
spinlock_t lock;
struct kfifo fifo;
struct work_struct work;
- struct tasklet_struct tasklet;
struct omap_mbox *mbox;
bool full;
};
@@ -92,6 +92,7 @@ struct omap_mbox_device {
u32 num_users;
u32 num_fifos;
struct omap_mbox **mboxes;
+ struct mbox_controller controller;
struct list_head elem;
};
@@ -110,15 +111,14 @@ struct omap_mbox_fifo_info {
struct omap_mbox {
const char *name;
int irq;
- struct omap_mbox_queue *txq, *rxq;
+ struct omap_mbox_queue *rxq;
struct device *dev;
struct omap_mbox_device *parent;
struct omap_mbox_fifo tx_fifo;
struct omap_mbox_fifo rx_fifo;
u32 ctx[OMAP4_MBOX_NR_REGS];
u32 intr_type;
- int use_count;
- struct blocking_notifier_head notifier;
+ struct mbox_chan *chan;
};
/* global variables for the mailbox devices */
@@ -129,6 +129,14 @@ static unsigned int mbox_kfifo_size = CONFIG_OMAP_MBOX_KFIFO_SIZE;
module_param(mbox_kfifo_size, uint, S_IRUGO);
MODULE_PARM_DESC(mbox_kfifo_size, "Size of omap's mailbox kfifo (bytes)");
+static struct omap_mbox *mbox_chan_to_omap_mbox(struct mbox_chan *chan)
+{
+ if (!chan || !chan->con_priv)
+ return NULL;
+
+ return (struct omap_mbox *)chan->con_priv;
+}
+
static inline
unsigned int mbox_read_reg(struct omap_mbox_device *mdev, size_t ofs)
{
@@ -194,41 +202,14 @@ static int is_mbox_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
return (int)(enable & status & bit);
}
-/*
- * message sender
- */
-int omap_mbox_msg_send(struct omap_mbox *mbox, mbox_msg_t msg)
-{
- struct omap_mbox_queue *mq = mbox->txq;
- int ret = 0, len;
-
- spin_lock_bh(&mq->lock);
-
- if (kfifo_avail(&mq->fifo) < sizeof(msg)) {
- ret = -ENOMEM;
- goto out;
- }
-
- if (kfifo_is_empty(&mq->fifo) && !mbox_fifo_full(mbox)) {
- mbox_fifo_write(mbox, msg);
- goto out;
- }
-
- len = kfifo_in(&mq->fifo, (unsigned char *)&msg, sizeof(msg));
- WARN_ON(len != sizeof(msg));
-
- tasklet_schedule(&mbox->txq->tasklet);
-
-out:
- spin_unlock_bh(&mq->lock);
- return ret;
-}
-EXPORT_SYMBOL(omap_mbox_msg_send);
-
-void omap_mbox_save_ctx(struct omap_mbox *mbox)
+void omap_mbox_save_ctx(struct mbox_chan *chan)
{
int i;
int nr_regs;
+ struct omap_mbox *mbox = mbox_chan_to_omap_mbox(chan);
+
+ if (WARN_ON(!mbox))
+ return;
if (mbox->intr_type)
nr_regs = OMAP4_MBOX_NR_REGS;
@@ -243,10 +224,14 @@ void omap_mbox_save_ctx(struct omap_mbox *mbox)
}
EXPORT_SYMBOL(omap_mbox_save_ctx);
-void omap_mbox_restore_ctx(struct omap_mbox *mbox)
+void omap_mbox_restore_ctx(struct mbox_chan *chan)
{
int i;
int nr_regs;
+ struct omap_mbox *mbox = mbox_chan_to_omap_mbox(chan);
+
+ if (WARN_ON(!mbox))
+ return;
if (mbox->intr_type)
nr_regs = OMAP4_MBOX_NR_REGS;
@@ -254,14 +239,13 @@ void omap_mbox_restore_ctx(struct omap_mbox *mbox)
nr_regs = MBOX_NR_REGS;
for (i = 0; i < nr_regs; i++) {
mbox_write_reg(mbox->parent, mbox->ctx[i], i * sizeof(u32));
-
dev_dbg(mbox->dev, "%s: [%02x] %08x\n", __func__,
i, mbox->ctx[i]);
}
}
EXPORT_SYMBOL(omap_mbox_restore_ctx);
-void omap_mbox_enable_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
+static void _omap_mbox_enable_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
{
u32 l;
struct omap_mbox_fifo *fifo = (irq == IRQ_TX) ?
@@ -273,9 +257,8 @@ void omap_mbox_enable_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
l |= bit;
mbox_write_reg(mbox->parent, l, irqenable);
}
-EXPORT_SYMBOL(omap_mbox_enable_irq);
-void omap_mbox_disable_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
+static void _omap_mbox_disable_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
{
struct omap_mbox_fifo *fifo = (irq == IRQ_TX) ?
&mbox->tx_fifo : &mbox->rx_fifo;
@@ -291,28 +274,28 @@ void omap_mbox_disable_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
mbox_write_reg(mbox->parent, bit, irqdisable);
}
-EXPORT_SYMBOL(omap_mbox_disable_irq);
-static void mbox_tx_tasklet(unsigned long tx_data)
+void omap_mbox_enable_irq(struct mbox_chan *chan, omap_mbox_irq_t irq)
{
- struct omap_mbox *mbox = (struct omap_mbox *)tx_data;
- struct omap_mbox_queue *mq = mbox->txq;
- mbox_msg_t msg;
- int ret;
+ struct omap_mbox *mbox = mbox_chan_to_omap_mbox(chan);
- while (kfifo_len(&mq->fifo)) {
- if (mbox_fifo_full(mbox)) {
- omap_mbox_enable_irq(mbox, IRQ_TX);
- break;
- }
+ if (WARN_ON(!mbox))
+ return;
- ret = kfifo_out(&mq->fifo, (unsigned char *)&msg,
- sizeof(msg));
- WARN_ON(ret != sizeof(msg));
+ _omap_mbox_enable_irq(mbox, irq);
+}
+EXPORT_SYMBOL(omap_mbox_enable_irq);
- mbox_fifo_write(mbox, msg);
- }
+void omap_mbox_disable_irq(struct mbox_chan *chan, omap_mbox_irq_t irq)
+{
+ struct omap_mbox *mbox = mbox_chan_to_omap_mbox(chan);
+
+ if (WARN_ON(!mbox))
+ return;
+
+ _omap_mbox_disable_irq(mbox, irq);
}
+EXPORT_SYMBOL(omap_mbox_disable_irq);
/*
* Message receiver(workqueue)
@@ -328,12 +311,11 @@ static void mbox_rx_work(struct work_struct *work)
len = kfifo_out(&mq->fifo, (unsigned char *)&msg, sizeof(msg));
WARN_ON(len != sizeof(msg));
- blocking_notifier_call_chain(&mq->mbox->notifier, len,
- (void *)msg);
+ mbox_chan_received_data(mq->mbox->chan, (void *)msg);
spin_lock_irq(&mq->lock);
if (mq->full) {
mq->full = false;
- omap_mbox_enable_irq(mq->mbox, IRQ_RX);
+ _omap_mbox_enable_irq(mq->mbox, IRQ_RX);
}
spin_unlock_irq(&mq->lock);
}
@@ -344,9 +326,9 @@ static void mbox_rx_work(struct work_struct *work)
*/
static void __mbox_tx_interrupt(struct omap_mbox *mbox)
{
- omap_mbox_disable_irq(mbox, IRQ_TX);
+ _omap_mbox_disable_irq(mbox, IRQ_TX);
ack_mbox_irq(mbox, IRQ_TX);
- tasklet_schedule(&mbox->txq->tasklet);
+ mbox_chan_txdone(mbox->chan, 0);
}
static void __mbox_rx_interrupt(struct omap_mbox *mbox)
@@ -357,7 +339,7 @@ static void __mbox_rx_interrupt(struct omap_mbox *mbox)
while (!mbox_fifo_empty(mbox)) {
if (unlikely(kfifo_avail(&mq->fifo) < sizeof(msg))) {
- omap_mbox_disable_irq(mbox, IRQ_RX);
+ _omap_mbox_disable_irq(mbox, IRQ_RX);
mq->full = true;
goto nomem;
}
@@ -388,11 +370,13 @@ static irqreturn_t mbox_interrupt(int irq, void *p)
}
static struct omap_mbox_queue *mbox_queue_alloc(struct omap_mbox *mbox,
- void (*work) (struct work_struct *),
- void (*tasklet)(unsigned long))
+ void (*work)(struct work_struct *))
{
struct omap_mbox_queue *mq;
+ if (!work)
+ return NULL;
+
mq = kzalloc(sizeof(struct omap_mbox_queue), GFP_KERNEL);
if (!mq)
return NULL;
@@ -402,12 +386,9 @@ static struct omap_mbox_queue *mbox_queue_alloc(struct omap_mbox *mbox,
if (kfifo_alloc(&mq->fifo, mbox_kfifo_size, GFP_KERNEL))
goto error;
- if (work)
- INIT_WORK(&mq->work, work);
-
- if (tasklet)
- tasklet_init(&mq->tasklet, tasklet, (unsigned long)mbox);
+ INIT_WORK(&mq->work, work);
return mq;
+
error:
kfree(mq);
return NULL;
@@ -423,71 +404,35 @@ static int omap_mbox_startup(struct omap_mbox *mbox)
{
int ret = 0;
struct omap_mbox_queue *mq;
- struct omap_mbox_device *mdev = mbox->parent;
- mutex_lock(&mdev->cfg_lock);
- ret = pm_runtime_get_sync(mdev->dev);
- if (unlikely(ret < 0))
- goto fail_startup;
-
- if (!mbox->use_count++) {
- mq = mbox_queue_alloc(mbox, NULL, mbox_tx_tasklet);
- if (!mq) {
- ret = -ENOMEM;
- goto fail_alloc_txq;
- }
- mbox->txq = mq;
+ mq = mbox_queue_alloc(mbox, mbox_rx_work);
+ if (!mq)
+ return -ENOMEM;
+ mbox->rxq = mq;
+ mq->mbox = mbox;
+
+ ret = request_irq(mbox->irq, mbox_interrupt, IRQF_SHARED,
+ mbox->name, mbox);
+ if (unlikely(ret)) {
+ pr_err("failed to register mailbox interrupt:%d\n", ret);
+ goto fail_request_irq;
+ }
- mq = mbox_queue_alloc(mbox, mbox_rx_work, NULL);
- if (!mq) {
- ret = -ENOMEM;
- goto fail_alloc_rxq;
- }
- mbox->rxq = mq;
- mq->mbox = mbox;
- ret = request_irq(mbox->irq, mbox_interrupt, IRQF_SHARED,
- mbox->name, mbox);
- if (unlikely(ret)) {
- pr_err("failed to register mailbox interrupt:%d\n",
- ret);
- goto fail_request_irq;
- }
+ _omap_mbox_enable_irq(mbox, IRQ_RX);
- omap_mbox_enable_irq(mbox, IRQ_RX);
- }
- mutex_unlock(&mdev->cfg_lock);
return 0;
fail_request_irq:
mbox_queue_free(mbox->rxq);
-fail_alloc_rxq:
- mbox_queue_free(mbox->txq);
-fail_alloc_txq:
- pm_runtime_put_sync(mdev->dev);
- mbox->use_count--;
-fail_startup:
- mutex_unlock(&mdev->cfg_lock);
return ret;
}
static void omap_mbox_fini(struct omap_mbox *mbox)
{
- struct omap_mbox_device *mdev = mbox->parent;
-
- mutex_lock(&mdev->cfg_lock);
-
- if (!--mbox->use_count) {
- omap_mbox_disable_irq(mbox, IRQ_RX);
- free_irq(mbox->irq, mbox);
- tasklet_kill(&mbox->txq->tasklet);
- flush_work(&mbox->rxq->work);
- mbox_queue_free(mbox->txq);
- mbox_queue_free(mbox->rxq);
- }
-
- pm_runtime_put_sync(mdev->dev);
-
- mutex_unlock(&mdev->cfg_lock);
+ _omap_mbox_disable_irq(mbox, IRQ_RX);
+ free_irq(mbox->irq, mbox);
+ flush_work(&mbox->rxq->work);
+ mbox_queue_free(mbox->rxq);
}
static struct omap_mbox *omap_mbox_device_find(struct omap_mbox_device *mdev,
@@ -509,42 +454,55 @@ static struct omap_mbox *omap_mbox_device_find(struct omap_mbox_device *mdev,
return mbox;
}
-struct omap_mbox *omap_mbox_get(const char *name, struct notifier_block *nb)
+struct mbox_chan *omap_mbox_request_channel(struct mbox_client *cl,
+ const char *chan_name)
{
+ struct device *dev = cl->dev;
struct omap_mbox *mbox = NULL;
struct omap_mbox_device *mdev;
+ struct mbox_chan *chan;
+ unsigned long flags;
int ret;
+ if (!dev)
+ return ERR_PTR(-ENODEV);
+
+ if (dev->of_node) {
+ pr_err("%s: please use mbox_request_channel(), this API is supported only for OMAP non-DT usage\n",
+ __func__);
+ return ERR_PTR(-ENODEV);
+ }
+
mutex_lock(&omap_mbox_devices_lock);
list_for_each_entry(mdev, &omap_mbox_devices, elem) {
- mbox = omap_mbox_device_find(mdev, name);
+ mbox = omap_mbox_device_find(mdev, chan_name);
if (mbox)
break;
}
mutex_unlock(&omap_mbox_devices_lock);
- if (!mbox)
+ if (!mbox || !mbox->chan)
return ERR_PTR(-ENOENT);
- if (nb)
- blocking_notifier_chain_register(&mbox->notifier, nb);
+ chan = mbox->chan;
+ spin_lock_irqsave(&chan->lock, flags);
+ chan->msg_free = 0;
+ chan->msg_count = 0;
+ chan->active_req = NULL;
+ chan->cl = cl;
+ init_completion(&chan->tx_complete);
+ spin_unlock_irqrestore(&chan->lock, flags);
- ret = omap_mbox_startup(mbox);
+ ret = chan->mbox->ops->startup(chan);
if (ret) {
- blocking_notifier_chain_unregister(&mbox->notifier, nb);
- return ERR_PTR(-ENODEV);
+ pr_err("Unable to startup the chan (%d)\n", ret);
+ mbox_free_channel(chan);
+ chan = ERR_PTR(ret);
}
- return mbox;
-}
-EXPORT_SYMBOL(omap_mbox_get);
-
-void omap_mbox_put(struct omap_mbox *mbox, struct notifier_block *nb)
-{
- blocking_notifier_chain_unregister(&mbox->notifier, nb);
- omap_mbox_fini(mbox);
+ return chan;
}
-EXPORT_SYMBOL(omap_mbox_put);
+EXPORT_SYMBOL(omap_mbox_request_channel);
static struct class omap_mbox_class = { .name = "mbox", };
@@ -560,25 +518,25 @@ static int omap_mbox_register(struct omap_mbox_device *mdev)
mboxes = mdev->mboxes;
for (i = 0; mboxes[i]; i++) {
struct omap_mbox *mbox = mboxes[i];
- mbox->dev = device_create(&omap_mbox_class,
- mdev->dev, 0, mbox, "%s", mbox->name);
+ mbox->dev = device_create(&omap_mbox_class, mdev->dev,
+ 0, mbox, "%s", mbox->name);
if (IS_ERR(mbox->dev)) {
ret = PTR_ERR(mbox->dev);
goto err_out;
}
-
- BLOCKING_INIT_NOTIFIER_HEAD(&mbox->notifier);
}
mutex_lock(&omap_mbox_devices_lock);
list_add(&mdev->elem, &omap_mbox_devices);
mutex_unlock(&omap_mbox_devices_lock);
- return 0;
+ ret = mbox_controller_register(&mdev->controller);
err_out:
- while (i--)
- device_unregister(mboxes[i]->dev);
+ if (ret) {
+ while (i--)
+ device_unregister(mboxes[i]->dev);
+ }
return ret;
}
@@ -594,12 +552,64 @@ static int omap_mbox_unregister(struct omap_mbox_device *mdev)
list_del(&mdev->elem);
mutex_unlock(&omap_mbox_devices_lock);
+ mbox_controller_unregister(&mdev->controller);
+
mboxes = mdev->mboxes;
for (i = 0; mboxes[i]; i++)
device_unregister(mboxes[i]->dev);
return 0;
}
+static int omap_mbox_chan_startup(struct mbox_chan *chan)
+{
+ struct omap_mbox *mbox = mbox_chan_to_omap_mbox(chan);
+ struct omap_mbox_device *mdev = mbox->parent;
+ int ret = 0;
+
+ mutex_lock(&mdev->cfg_lock);
+ pm_runtime_get_sync(mdev->dev);
+ ret = omap_mbox_startup(mbox);
+ if (ret)
+ pm_runtime_put_sync(mdev->dev);
+ mutex_unlock(&mdev->cfg_lock);
+ return ret;
+}
+
+static void omap_mbox_chan_shutdown(struct mbox_chan *chan)
+{
+ struct omap_mbox *mbox = mbox_chan_to_omap_mbox(chan);
+ struct omap_mbox_device *mdev = mbox->parent;
+
+ mutex_lock(&mdev->cfg_lock);
+ omap_mbox_fini(mbox);
+ pm_runtime_put_sync(mdev->dev);
+ mutex_unlock(&mdev->cfg_lock);
+}
+
+static int omap_mbox_chan_send_data(struct mbox_chan *chan, void *data)
+{
+ struct omap_mbox *mbox = mbox_chan_to_omap_mbox(chan);
+ int ret = -EBUSY;
+
+ if (!mbox)
+ return -EINVAL;
+
+ if (!mbox_fifo_full(mbox)) {
+ mbox_fifo_write(mbox, (mbox_msg_t)data);
+ ret = 0;
+ }
+
+ /* always enable the interrupt */
+ _omap_mbox_enable_irq(mbox, IRQ_TX);
+ return ret;
+}
+
+static struct mbox_chan_ops omap_mbox_chan_ops = {
+ .startup = omap_mbox_chan_startup,
+ .send_data = omap_mbox_chan_send_data,
+ .shutdown = omap_mbox_chan_shutdown,
+};
+
static const struct of_device_id omap_mailbox_of_match[] = {
{
.compatible = "ti,omap2-mailbox",
@@ -619,10 +629,35 @@ static const struct of_device_id omap_mailbox_of_match[] = {
};
MODULE_DEVICE_TABLE(of, omap_mailbox_of_match);
+static struct mbox_chan *omap_mbox_of_xlate(struct mbox_controller *controller,
+ const struct of_phandle_args *sp)
+{
+ phandle phandle = sp->args[0];
+ struct device_node *node;
+ struct omap_mbox_device *mdev;
+ struct omap_mbox *mbox;
+
+ mdev = container_of(controller, struct omap_mbox_device, controller);
+ if (WARN_ON(!mdev))
+ return NULL;
+
+ node = of_find_node_by_phandle(phandle);
+ if (!node) {
+ pr_err("%s: could not find node phandle 0x%x\n",
+ __func__, phandle);
+ return NULL;
+ }
+
+ mbox = omap_mbox_device_find(mdev, node->name);
+ of_node_put(node);
+ return mbox ? mbox->chan : NULL;
+}
+
static int omap_mbox_probe(struct platform_device *pdev)
{
struct resource *mem;
int ret;
+ struct mbox_chan *chnls;
struct omap_mbox **list, *mbox, *mboxblk;
struct omap_mbox_pdata *pdata = pdev->dev.platform_data;
struct omap_mbox_dev_info *info = NULL;
@@ -727,6 +762,11 @@ static int omap_mbox_probe(struct platform_device *pdev)
if (!list)
return -ENOMEM;
+ chnls = devm_kzalloc(&pdev->dev, (info_count + 1) * sizeof(*chnls),
+ GFP_KERNEL);
+ if (!chnls)
+ return -ENOMEM;
+
mboxblk = devm_kzalloc(&pdev->dev, info_count * sizeof(*mbox),
GFP_KERNEL);
if (!mboxblk)
@@ -758,6 +798,8 @@ static int omap_mbox_probe(struct platform_device *pdev)
mbox->irq = platform_get_irq(pdev, finfo->tx_irq);
if (mbox->irq < 0)
return mbox->irq;
+ mbox->chan = &chnls[i];
+ chnls[i].con_priv = mbox;
list[i] = mbox++;
}
@@ -766,6 +808,14 @@ static int omap_mbox_probe(struct platform_device *pdev)
mdev->num_users = num_users;
mdev->num_fifos = num_fifos;
mdev->mboxes = list;
+
+ /* OMAP does not have a Tx-Done IRQ, but rather a Tx-Ready IRQ */
+ mdev->controller.txdone_irq = true;
+ mdev->controller.dev = mdev->dev;
+ mdev->controller.ops = &omap_mbox_chan_ops;
+ mdev->controller.chans = chnls;
+ mdev->controller.num_chans = info_count;
+ mdev->controller.of_xlate = omap_mbox_of_xlate;
ret = omap_mbox_register(mdev);
if (ret)
return ret;
@@ -814,7 +864,6 @@ static struct platform_driver omap_mbox_driver = {
.remove = omap_mbox_remove,
.driver = {
.name = "omap-mailbox",
- .owner = THIS_MODULE,
.of_match_table = of_match_ptr(omap_mailbox_of_match),
},
};
diff --git a/drivers/mailbox/pcc.c b/drivers/mailbox/pcc.c
new file mode 100644
index 000000000000..6dbf6fcbdfaf
--- /dev/null
+++ b/drivers/mailbox/pcc.c
@@ -0,0 +1,403 @@
+/*
+ * Copyright (C) 2014 Linaro Ltd.
+ * Author: Ashwin Chaugule <ashwin.chaugule@linaro.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * PCC (Platform Communication Channel) is defined in the ACPI 5.0+
+ * specification. It is a mailbox like mechanism to allow clients
+ * such as CPPC (Collaborative Processor Performance Control), RAS
+ * (Reliability, Availability and Serviceability) and MPST (Memory
+ * Node Power State Table) to talk to the platform (e.g. BMC) through
+ * shared memory regions as defined in the PCC table entries. The PCC
+ * specification supports a Doorbell mechanism for the PCC clients
+ * to notify the platform about new data. This Doorbell information
+ * is also specified in each PCC table entry. See pcc_send_data()
+ * and pcc_tx_done() for basic mode of operation.
+ *
+ * For more details about PCC, please see the ACPI specification from
+ * http://www.uefi.org/ACPIv5.1 Section 14.
+ *
+ * This file implements PCC as a Mailbox controller and allows for PCC
+ * clients to be implemented as its Mailbox Client Channels.
+ */
+
+#include <linux/acpi.h>
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/init.h>
+#include <linux/list.h>
+#include <linux/platform_device.h>
+#include <linux/mailbox_controller.h>
+#include <linux/mailbox_client.h>
+
+#include "mailbox.h"
+
+#define MAX_PCC_SUBSPACES 256
+#define PCCS_SS_SIG_MAGIC 0x50434300
+#define PCC_CMD_COMPLETE 0x1
+
+static struct mbox_chan *pcc_mbox_channels;
+
+static struct mbox_controller pcc_mbox_ctrl = {};
+/**
+ * get_pcc_channel - Given a PCC subspace idx, get
+ * the respective mbox_channel.
+ * @id: PCC subspace index.
+ *
+ * Return: ERR_PTR(errno) if error, else pointer
+ * to mbox channel.
+ */
+static struct mbox_chan *get_pcc_channel(int id)
+{
+ struct mbox_chan *pcc_chan;
+
+ if (id < 0 || id > pcc_mbox_ctrl.num_chans)
+ return ERR_PTR(-ENOENT);
+
+ pcc_chan = (struct mbox_chan *)
+ (unsigned long) pcc_mbox_channels +
+ (id * sizeof(*pcc_chan));
+
+ return pcc_chan;
+}
+
+/**
+ * get_subspace_id - Given a Mailbox channel, find out the
+ * PCC subspace id.
+ * @chan: Pointer to Mailbox Channel from which we want
+ * the index.
+ * Return: Errno if not found, else positive index number.
+ */
+static int get_subspace_id(struct mbox_chan *chan)
+{
+ unsigned int id = chan - pcc_mbox_channels;
+
+ if (id < 0 || id > pcc_mbox_ctrl.num_chans)
+ return -ENOENT;
+
+ return id;
+}
+
+/**
+ * pcc_mbox_request_channel - PCC clients call this function to
+ * request a pointer to their PCC subspace, from which they
+ * can get the details of communicating with the remote.
+ * @cl: Pointer to Mailbox client, so we know where to bind the
+ * Channel.
+ * @subspace_id: The PCC Subspace index as parsed in the PCC client
+ * ACPI package. This is used to lookup the array of PCC
+ * subspaces as parsed by the PCC Mailbox controller.
+ *
+ * Return: Pointer to the Mailbox Channel if successful or
+ * ERR_PTR.
+ */
+struct mbox_chan *pcc_mbox_request_channel(struct mbox_client *cl,
+ int subspace_id)
+{
+ struct device *dev = pcc_mbox_ctrl.dev;
+ struct mbox_chan *chan;
+ unsigned long flags;
+
+ /*
+ * Each PCC Subspace is a Mailbox Channel.
+ * The PCC Clients get their PCC Subspace ID
+ * from their own tables and pass it here.
+ * This returns a pointer to the PCC subspace
+ * for the Client to operate on.
+ */
+ chan = get_pcc_channel(subspace_id);
+
+ if (!chan || chan->cl) {
+ dev_err(dev, "%s: PCC mailbox not free\n", __func__);
+ return ERR_PTR(-EBUSY);
+ }
+
+ spin_lock_irqsave(&chan->lock, flags);
+ chan->msg_free = 0;
+ chan->msg_count = 0;
+ chan->active_req = NULL;
+ chan->cl = cl;
+ init_completion(&chan->tx_complete);
+
+ if (chan->txdone_method == TXDONE_BY_POLL && cl->knows_txdone)
+ chan->txdone_method |= TXDONE_BY_ACK;
+
+ spin_unlock_irqrestore(&chan->lock, flags);
+
+ return chan;
+}
+EXPORT_SYMBOL_GPL(pcc_mbox_request_channel);
+
+/**
+ * pcc_mbox_free_channel - Clients call this to free their Channel.
+ *
+ * @chan: Pointer to the mailbox channel as returned by
+ * pcc_mbox_request_channel()
+ */
+void pcc_mbox_free_channel(struct mbox_chan *chan)
+{
+ unsigned long flags;
+
+ if (!chan || !chan->cl)
+ return;
+
+ spin_lock_irqsave(&chan->lock, flags);
+ chan->cl = NULL;
+ chan->active_req = NULL;
+ if (chan->txdone_method == (TXDONE_BY_POLL | TXDONE_BY_ACK))
+ chan->txdone_method = TXDONE_BY_POLL;
+
+ spin_unlock_irqrestore(&chan->lock, flags);
+}
+EXPORT_SYMBOL_GPL(pcc_mbox_free_channel);
+
+/**
+ * pcc_tx_done - Callback from Mailbox controller code to
+ * check if PCC message transmission completed.
+ * @chan: Pointer to Mailbox channel on which previous
+ * transmission occurred.
+ *
+ * Return: TRUE if succeeded.
+ */
+static bool pcc_tx_done(struct mbox_chan *chan)
+{
+ struct acpi_pcct_hw_reduced *pcct_ss = chan->con_priv;
+ struct acpi_pcct_shared_memory *generic_comm_base =
+ (struct acpi_pcct_shared_memory *) pcct_ss->base_address;
+ u16 cmd_delay = pcct_ss->latency;
+ unsigned int retries = 0;
+
+ /* Try a few times while waiting for platform to consume */
+ while (!(readw_relaxed(&generic_comm_base->status)
+ & PCC_CMD_COMPLETE)) {
+
+ if (retries++ < 5)
+ udelay(cmd_delay);
+ else {
+ /*
+ * If the remote is dead, this will cause the Mbox
+ * controller to timeout after mbox client.tx_tout
+ * msecs.
+ */
+ pr_err("PCC platform did not respond.\n");
+ return false;
+ }
+ }
+ return true;
+}
+
+/**
+ * pcc_send_data - Called from Mailbox Controller code to finally
+ * transmit data over channel.
+ * @chan: Pointer to Mailbox channel over which to send data.
+ * @data: Actual data to be written over channel.
+ *
+ * Return: Err if something failed else 0 for success.
+ */
+static int pcc_send_data(struct mbox_chan *chan, void *data)
+{
+ struct acpi_pcct_hw_reduced *pcct_ss = chan->con_priv;
+ struct acpi_pcct_shared_memory *generic_comm_base =
+ (struct acpi_pcct_shared_memory *) pcct_ss->base_address;
+ struct acpi_generic_address doorbell;
+ u64 doorbell_preserve;
+ u64 doorbell_val;
+ u64 doorbell_write;
+ u16 cmd = *(u16 *) data;
+ u16 ss_idx = -1;
+
+ ss_idx = get_subspace_id(chan);
+
+ if (ss_idx < 0) {
+ pr_err("Invalid Subspace ID from PCC client\n");
+ return -EINVAL;
+ }
+
+ doorbell = pcct_ss->doorbell_register;
+ doorbell_preserve = pcct_ss->preserve_mask;
+ doorbell_write = pcct_ss->write_mask;
+
+ /* Write to the shared comm region. */
+ writew(cmd, &generic_comm_base->command);
+
+ /* Write Subspace MAGIC value so platform can identify destination. */
+ writel((PCCS_SS_SIG_MAGIC | ss_idx), &generic_comm_base->signature);
+
+ /* Flip CMD COMPLETE bit */
+ writew(0, &generic_comm_base->status);
+
+ /* Sync notification from OSPM to Platform. */
+ acpi_read(&doorbell_val, &doorbell);
+ acpi_write((doorbell_val & doorbell_preserve) | doorbell_write,
+ &doorbell);
+
+ return 0;
+}
+
+static struct mbox_chan_ops pcc_chan_ops = {
+ .send_data = pcc_send_data,
+ .last_tx_done = pcc_tx_done,
+};
+
+/**
+ * parse_pcc_subspace - Parse the PCC table and verify PCC subspace
+ * entries. There should be one entry per PCC client.
+ * @header: Pointer to the ACPI subtable header under the PCCT.
+ * @end: End of subtable entry.
+ *
+ * Return: 0 for Success, else errno.
+ *
+ * This gets called for each entry in the PCC table.
+ */
+static int parse_pcc_subspace(struct acpi_subtable_header *header,
+ const unsigned long end)
+{
+ struct acpi_pcct_hw_reduced *pcct_ss;
+
+ if (pcc_mbox_ctrl.num_chans <= MAX_PCC_SUBSPACES) {
+ pcct_ss = (struct acpi_pcct_hw_reduced *) header;
+
+ if (pcct_ss->header.type !=
+ ACPI_PCCT_TYPE_HW_REDUCED_SUBSPACE) {
+ pr_err("Incorrect PCC Subspace type detected\n");
+ return -EINVAL;
+ }
+ }
+
+ return 0;
+}
+
+/**
+ * acpi_pcc_probe - Parse the ACPI tree for the PCCT.
+ *
+ * Return: 0 for Success, else errno.
+ */
+static int __init acpi_pcc_probe(void)
+{
+ acpi_size pcct_tbl_header_size;
+ struct acpi_table_header *pcct_tbl;
+ struct acpi_subtable_header *pcct_entry;
+ int count, i;
+ acpi_status status = AE_OK;
+
+ /* Search for PCCT */
+ status = acpi_get_table_with_size(ACPI_SIG_PCCT, 0,
+ &pcct_tbl,
+ &pcct_tbl_header_size);
+
+ if (ACPI_FAILURE(status) || !pcct_tbl) {
+ pr_warn("PCCT header not found.\n");
+ return -ENODEV;
+ }
+
+ count = acpi_table_parse_entries(ACPI_SIG_PCCT,
+ sizeof(struct acpi_table_pcct),
+ ACPI_PCCT_TYPE_HW_REDUCED_SUBSPACE,
+ parse_pcc_subspace, MAX_PCC_SUBSPACES);
+
+ if (count <= 0) {
+ pr_err("Error parsing PCC subspaces from PCCT\n");
+ return -EINVAL;
+ }
+
+ pcc_mbox_channels = kzalloc(sizeof(struct mbox_chan) *
+ count, GFP_KERNEL);
+
+ if (!pcc_mbox_channels) {
+ pr_err("Could not allocate space for PCC mbox channels\n");
+ return -ENOMEM;
+ }
+
+ /* Point to the first PCC subspace entry */
+ pcct_entry = (struct acpi_subtable_header *) (
+ (unsigned long) pcct_tbl + sizeof(struct acpi_table_pcct));
+
+ for (i = 0; i < count; i++) {
+ pcc_mbox_channels[i].con_priv = pcct_entry;
+ pcct_entry = (struct acpi_subtable_header *)
+ ((unsigned long) pcct_entry + pcct_entry->length);
+ }
+
+ pcc_mbox_ctrl.num_chans = count;
+
+ pr_info("Detected %d PCC Subspaces\n", pcc_mbox_ctrl.num_chans);
+
+ return 0;
+}
+
+/**
+ * pcc_mbox_probe - Called when we find a match for the
+ * PCCT platform device. This is purely used to represent
+ * the PCCT as a virtual device for registering with the
+ * generic Mailbox framework.
+ *
+ * @pdev: Pointer to platform device returned when a match
+ * is found.
+ *
+ * Return: 0 for Success, else errno.
+ */
+static int pcc_mbox_probe(struct platform_device *pdev)
+{
+ int ret = 0;
+
+ pcc_mbox_ctrl.chans = pcc_mbox_channels;
+ pcc_mbox_ctrl.ops = &pcc_chan_ops;
+ pcc_mbox_ctrl.txdone_poll = true;
+ pcc_mbox_ctrl.txpoll_period = 10;
+ pcc_mbox_ctrl.dev = &pdev->dev;
+
+ pr_info("Registering PCC driver as Mailbox controller\n");
+ ret = mbox_controller_register(&pcc_mbox_ctrl);
+
+ if (ret) {
+ pr_err("Err registering PCC as Mailbox controller: %d\n", ret);
+ ret = -ENODEV;
+ }
+
+ return ret;
+}
+
+struct platform_driver pcc_mbox_driver = {
+ .probe = pcc_mbox_probe,
+ .driver = {
+ .name = "PCCT",
+ .owner = THIS_MODULE,
+ },
+};
+
+static int __init pcc_init(void)
+{
+ int ret;
+ struct platform_device *pcc_pdev;
+
+ if (acpi_disabled)
+ return -ENODEV;
+
+ /* Check if PCC support is available. */
+ ret = acpi_pcc_probe();
+
+ if (ret) {
+ pr_err("ACPI PCC probe failed.\n");
+ return -ENODEV;
+ }
+
+ pcc_pdev = platform_create_bundle(&pcc_mbox_driver,
+ pcc_mbox_probe, NULL, 0, NULL, 0);
+
+ if (!pcc_pdev) {
+ pr_err("Err creating PCC platform bundle\n");
+ return -ENODEV;
+ }
+
+ return 0;
+}
+device_initcall(pcc_init);
diff --git a/drivers/mailbox/pl320-ipc.c b/drivers/mailbox/pl320-ipc.c
index d873cbae2fbb..f3755e0aa935 100644
--- a/drivers/mailbox/pl320-ipc.c
+++ b/drivers/mailbox/pl320-ipc.c
@@ -26,7 +26,7 @@
#include <linux/device.h>
#include <linux/amba/bus.h>
-#include <linux/mailbox.h>
+#include <linux/pl320-ipc.h>
#define IPCMxSOURCE(m) ((m) * 0x40)
#define IPCMxDSET(m) (((m) * 0x40) + 0x004)
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