diff --git a/drivers/mailbox/Kconfig b/drivers/mailbox/Kconfig
index 9fd9c67..c04fed9 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 94ed7ce..dd412c2 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 afcb430..17e9e4a 100644
--- a/drivers/mailbox/mailbox.c
+++ b/drivers/mailbox/mailbox.c
@@ -21,9 +21,7 @@
 #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);
diff --git a/drivers/mailbox/mailbox.h b/drivers/mailbox/mailbox.h
new file mode 100644
index 0000000..5a15a25
--- /dev/null
+++ b/drivers/mailbox/mailbox.h
@@ -0,0 +1,16 @@
+/*
+ * 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/pcc.c b/drivers/mailbox/pcc.c
new file mode 100644
index 0000000..0006fc3
--- /dev/null
+++ b/drivers/mailbox/pcc.c
@@ -0,0 +1,369 @@
+/*
+ *	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/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_chan[MAX_PCC_SUBSPACES];
+static struct mbox_controller pcc_mbox_ctrl = {};
+
+/**
+ * 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.
+ * @index: 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 index)
+{
+	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 = &pcc_mbox_chan[index];
+
+	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_subspace *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->min_turnaround_time;
+	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;
+}
+
+/**
+ * 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)
+{
+	int id = chan - pcc_mbox_chan;
+
+	if (id < 0 || id > pcc_mbox_ctrl.num_chans)
+		return -ENOENT;
+
+	return id;
+}
+
+/**
+ * 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_subspace *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;
+	int ret = 0;
+
+	ss_idx = get_subspace_id(chan);
+
+	if (ss_idx < 0) {
+		pr_err("Invalid Subspace ID from PCC client\n");
+		ret = -EINVAL;
+		goto out_err;
+	}
+
+	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);
+
+out_err:
+	return ret;
+}
+
+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 extract 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_subspace *pcct_ss;
+
+	if (pcc_mbox_ctrl.num_chans <= MAX_PCC_SUBSPACES) {
+		pcct_ss = (struct acpi_pcct_subspace *) header;
+
+		if (pcct_ss->header.type != ACPI_PCCT_TYPE_GENERIC_SUBSPACE) {
+			pr_err("Incorrect PCC Subspace type detected\n");
+			return -EINVAL;
+		}
+
+		/* New mbox channel entry for each PCC subspace detected. */
+		pcc_mbox_chan[pcc_mbox_ctrl.num_chans].con_priv = pcct_ss;
+		pcc_mbox_ctrl.num_chans++;
+
+	} else {
+		pr_err("No more space for PCC subspaces.\n");
+		return -ENOSPC;
+	}
+
+	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_status status = AE_OK;
+	acpi_size pcct_tbl_header_size;
+	int count;
+	struct acpi_table_pcct *pcct_tbl;
+
+	/* Search for PCCT */
+	status = acpi_get_table_with_size(ACPI_SIG_PCCT, 0,
+			(struct acpi_table_header **)&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_GENERIC_SUBSPACE,
+			parse_pcc_subspace, MAX_PCC_SUBSPACES);
+
+	if (count <= 0) {
+		pr_err("Error parsing PCC subspaces from PCCT\n");
+		return -EINVAL;
+	}
+
+	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_chan;
+	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);
