summaryrefslogtreecommitdiff
path: root/drivers/mailbox
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/mailbox')
-rw-r--r--drivers/mailbox/Kconfig12
-rw-r--r--drivers/mailbox/Makefile2
-rw-r--r--drivers/mailbox/mailbox.c19
-rw-r--r--drivers/mailbox/mailbox.h14
-rw-r--r--drivers/mailbox/omap-mailbox.c346
-rw-r--r--drivers/mailbox/pcc.c403
6 files changed, 640 insertions, 156 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 94ed7cefb14d..dd412c22208b 100644
--- a/drivers/mailbox/Makefile
+++ b/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
diff --git a/drivers/mailbox/mailbox.c b/drivers/mailbox/mailbox.c
index afcb430508ec..59aad4d5da53 100644
--- a/drivers/mailbox/mailbox.c
+++ b/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;
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 42978c4b63fc..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;
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);