mailbox: Add Altera mailbox driver
The Altera mailbox allows for interprocessor communication. It supports only one channel and work as either sender or receiver. Signed-off-by: Ley Foon Tan <lftan@altera.com>
This commit is contained in:
Родитель
01340df8d3
Коммит
f62092f6d7
|
@ -0,0 +1,49 @@
|
|||
Altera Mailbox Driver
|
||||
=====================
|
||||
|
||||
Required properties:
|
||||
- compatible : "altr,mailbox-1.0".
|
||||
- reg : physical base address of the mailbox and length of
|
||||
memory mapped region.
|
||||
- #mbox-cells: Common mailbox binding property to identify the number
|
||||
of cells required for the mailbox specifier. Should be 1.
|
||||
|
||||
Optional properties:
|
||||
- interrupt-parent : interrupt source phandle.
|
||||
- interrupts : interrupt number. The interrupt specifier format
|
||||
depends on the interrupt controller parent.
|
||||
|
||||
Example:
|
||||
mbox_tx: mailbox@0x100 {
|
||||
compatible = "altr,mailbox-1.0";
|
||||
reg = <0x100 0x8>;
|
||||
interrupt-parent = < &gic_0 >;
|
||||
interrupts = <5>;
|
||||
#mbox-cells = <1>;
|
||||
};
|
||||
|
||||
mbox_rx: mailbox@0x200 {
|
||||
compatible = "altr,mailbox-1.0";
|
||||
reg = <0x200 0x8>;
|
||||
interrupt-parent = < &gic_0 >;
|
||||
interrupts = <6>;
|
||||
#mbox-cells = <1>;
|
||||
};
|
||||
|
||||
Mailbox client
|
||||
===============
|
||||
"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 second argument is the channel index. It must be 0 (hardware
|
||||
support only one channel).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:
|
||||
mclient0: mclient0@0x400 {
|
||||
compatible = "client-1.0";
|
||||
reg = <0x400 0x10>;
|
||||
mbox-names = "mbox-tx", "mbox-rx";
|
||||
mboxes = <&mbox_tx 0>,
|
||||
<&mbox_rx 0>;
|
||||
};
|
|
@ -563,6 +563,12 @@ S: Odd Fixes
|
|||
L: linux-alpha@vger.kernel.org
|
||||
F: arch/alpha/
|
||||
|
||||
ALTERA MAILBOX DRIVER
|
||||
M: Ley Foon Tan <lftan@altera.com>
|
||||
L: nios2-dev@lists.rocketboards.org (moderated for non-subscribers)
|
||||
S: Maintained
|
||||
F: drivers/mailbox/mailbox-altera.c
|
||||
|
||||
ALTERA TRIPLE SPEED ETHERNET DRIVER
|
||||
M: Vince Bridgers <vbridger@opensource.altera.com>
|
||||
L: netdev@vger.kernel.org
|
||||
|
|
|
@ -45,4 +45,10 @@ config PCC
|
|||
states). Select this driver if your platform implements the
|
||||
PCC clients mentioned above.
|
||||
|
||||
config ALTERA_MBOX
|
||||
tristate "Altera Mailbox"
|
||||
help
|
||||
An implementation of the Altera Mailbox soft core. It is used
|
||||
to send message between processors. Say Y here if you want to use the
|
||||
Altera mailbox support.
|
||||
endif
|
||||
|
|
|
@ -7,3 +7,5 @@ obj-$(CONFIG_PL320_MBOX) += pl320-ipc.o
|
|||
obj-$(CONFIG_OMAP2PLUS_MBOX) += omap-mailbox.o
|
||||
|
||||
obj-$(CONFIG_PCC) += pcc.o
|
||||
|
||||
obj-$(CONFIG_ALTERA_MBOX) += mailbox-altera.o
|
||||
|
|
|
@ -0,0 +1,388 @@
|
|||
/*
|
||||
* Copyright Altera Corporation (C) 2013-2014. All rights reserved
|
||||
*
|
||||
* This program is free software; you can redistribute it and/or modify it
|
||||
* under the terms and conditions of the GNU General Public License,
|
||||
* version 2, as published by the Free Software Foundation.
|
||||
*
|
||||
* This program is distributed in the hope 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.
|
||||
*
|
||||
* You should have received a copy of the GNU General Public License along with
|
||||
* this program. If not, see <http://www.gnu.org/licenses/>.
|
||||
*/
|
||||
|
||||
#include <linux/device.h>
|
||||
#include <linux/interrupt.h>
|
||||
#include <linux/io.h>
|
||||
#include <linux/kernel.h>
|
||||
#include <linux/mailbox_controller.h>
|
||||
#include <linux/module.h>
|
||||
#include <linux/of.h>
|
||||
#include <linux/platform_device.h>
|
||||
|
||||
#define DRIVER_NAME "altera-mailbox"
|
||||
|
||||
#define MAILBOX_CMD_REG 0x00
|
||||
#define MAILBOX_PTR_REG 0x04
|
||||
#define MAILBOX_STS_REG 0x08
|
||||
#define MAILBOX_INTMASK_REG 0x0C
|
||||
|
||||
#define INT_PENDING_MSK 0x1
|
||||
#define INT_SPACE_MSK 0x2
|
||||
|
||||
#define STS_PENDING_MSK 0x1
|
||||
#define STS_FULL_MSK 0x2
|
||||
#define STS_FULL_OFT 0x1
|
||||
|
||||
#define MBOX_PENDING(status) (((status) & STS_PENDING_MSK))
|
||||
#define MBOX_FULL(status) (((status) & STS_FULL_MSK) >> STS_FULL_OFT)
|
||||
|
||||
enum altera_mbox_msg {
|
||||
MBOX_CMD = 0,
|
||||
MBOX_PTR,
|
||||
};
|
||||
|
||||
#define MBOX_POLLING_MS 5 /* polling interval 5ms */
|
||||
|
||||
struct altera_mbox {
|
||||
bool is_sender; /* 1-sender, 0-receiver */
|
||||
bool intr_mode;
|
||||
int irq;
|
||||
void __iomem *mbox_base;
|
||||
struct device *dev;
|
||||
struct mbox_controller controller;
|
||||
|
||||
/* If the controller supports only RX polling mode */
|
||||
struct timer_list rxpoll_timer;
|
||||
};
|
||||
|
||||
static struct altera_mbox *mbox_chan_to_altera_mbox(struct mbox_chan *chan)
|
||||
{
|
||||
if (!chan || !chan->con_priv)
|
||||
return NULL;
|
||||
|
||||
return (struct altera_mbox *)chan->con_priv;
|
||||
}
|
||||
|
||||
static inline int altera_mbox_full(struct altera_mbox *mbox)
|
||||
{
|
||||
u32 status;
|
||||
|
||||
status = readl_relaxed(mbox->mbox_base + MAILBOX_STS_REG);
|
||||
return MBOX_FULL(status);
|
||||
}
|
||||
|
||||
static inline int altera_mbox_pending(struct altera_mbox *mbox)
|
||||
{
|
||||
u32 status;
|
||||
|
||||
status = readl_relaxed(mbox->mbox_base + MAILBOX_STS_REG);
|
||||
return MBOX_PENDING(status);
|
||||
}
|
||||
|
||||
static void altera_mbox_rx_intmask(struct altera_mbox *mbox, bool enable)
|
||||
{
|
||||
u32 mask;
|
||||
|
||||
mask = readl_relaxed(mbox->mbox_base + MAILBOX_INTMASK_REG);
|
||||
if (enable)
|
||||
mask |= INT_PENDING_MSK;
|
||||
else
|
||||
mask &= ~INT_PENDING_MSK;
|
||||
writel_relaxed(mask, mbox->mbox_base + MAILBOX_INTMASK_REG);
|
||||
}
|
||||
|
||||
static void altera_mbox_tx_intmask(struct altera_mbox *mbox, bool enable)
|
||||
{
|
||||
u32 mask;
|
||||
|
||||
mask = readl_relaxed(mbox->mbox_base + MAILBOX_INTMASK_REG);
|
||||
if (enable)
|
||||
mask |= INT_SPACE_MSK;
|
||||
else
|
||||
mask &= ~INT_SPACE_MSK;
|
||||
writel_relaxed(mask, mbox->mbox_base + MAILBOX_INTMASK_REG);
|
||||
}
|
||||
|
||||
static bool altera_mbox_is_sender(struct altera_mbox *mbox)
|
||||
{
|
||||
u32 reg;
|
||||
/* Write a magic number to PTR register and read back this register.
|
||||
* This register is read-write if it is a sender.
|
||||
*/
|
||||
#define MBOX_MAGIC 0xA5A5AA55
|
||||
writel_relaxed(MBOX_MAGIC, mbox->mbox_base + MAILBOX_PTR_REG);
|
||||
reg = readl_relaxed(mbox->mbox_base + MAILBOX_PTR_REG);
|
||||
if (reg == MBOX_MAGIC) {
|
||||
/* Clear to 0 */
|
||||
writel_relaxed(0, mbox->mbox_base + MAILBOX_PTR_REG);
|
||||
return true;
|
||||
}
|
||||
return false;
|
||||
}
|
||||
|
||||
static void altera_mbox_rx_data(struct mbox_chan *chan)
|
||||
{
|
||||
struct altera_mbox *mbox = mbox_chan_to_altera_mbox(chan);
|
||||
u32 data[2];
|
||||
|
||||
if (altera_mbox_pending(mbox)) {
|
||||
data[MBOX_PTR] =
|
||||
readl_relaxed(mbox->mbox_base + MAILBOX_PTR_REG);
|
||||
data[MBOX_CMD] =
|
||||
readl_relaxed(mbox->mbox_base + MAILBOX_CMD_REG);
|
||||
mbox_chan_received_data(chan, (void *)data);
|
||||
}
|
||||
}
|
||||
|
||||
static void altera_mbox_poll_rx(unsigned long data)
|
||||
{
|
||||
struct mbox_chan *chan = (struct mbox_chan *)data;
|
||||
struct altera_mbox *mbox = mbox_chan_to_altera_mbox(chan);
|
||||
|
||||
altera_mbox_rx_data(chan);
|
||||
|
||||
mod_timer(&mbox->rxpoll_timer,
|
||||
jiffies + msecs_to_jiffies(MBOX_POLLING_MS));
|
||||
}
|
||||
|
||||
static irqreturn_t altera_mbox_tx_interrupt(int irq, void *p)
|
||||
{
|
||||
struct mbox_chan *chan = (struct mbox_chan *)p;
|
||||
struct altera_mbox *mbox = mbox_chan_to_altera_mbox(chan);
|
||||
|
||||
altera_mbox_tx_intmask(mbox, false);
|
||||
mbox_chan_txdone(chan, 0);
|
||||
|
||||
return IRQ_HANDLED;
|
||||
}
|
||||
|
||||
static irqreturn_t altera_mbox_rx_interrupt(int irq, void *p)
|
||||
{
|
||||
struct mbox_chan *chan = (struct mbox_chan *)p;
|
||||
|
||||
altera_mbox_rx_data(chan);
|
||||
return IRQ_HANDLED;
|
||||
}
|
||||
|
||||
static int altera_mbox_startup_sender(struct mbox_chan *chan)
|
||||
{
|
||||
int ret;
|
||||
struct altera_mbox *mbox = mbox_chan_to_altera_mbox(chan);
|
||||
|
||||
if (mbox->intr_mode) {
|
||||
ret = request_irq(mbox->irq, altera_mbox_tx_interrupt, 0,
|
||||
DRIVER_NAME, chan);
|
||||
if (unlikely(ret)) {
|
||||
dev_err(mbox->dev,
|
||||
"failed to register mailbox interrupt:%d\n",
|
||||
ret);
|
||||
return ret;
|
||||
}
|
||||
}
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int altera_mbox_startup_receiver(struct mbox_chan *chan)
|
||||
{
|
||||
int ret;
|
||||
struct altera_mbox *mbox = mbox_chan_to_altera_mbox(chan);
|
||||
|
||||
if (mbox->intr_mode) {
|
||||
ret = request_irq(mbox->irq, altera_mbox_rx_interrupt, 0,
|
||||
DRIVER_NAME, chan);
|
||||
if (unlikely(ret)) {
|
||||
mbox->intr_mode = false;
|
||||
goto polling; /* use polling if failed */
|
||||
}
|
||||
|
||||
altera_mbox_rx_intmask(mbox, true);
|
||||
return 0;
|
||||
}
|
||||
|
||||
polling:
|
||||
/* Setup polling timer */
|
||||
setup_timer(&mbox->rxpoll_timer, altera_mbox_poll_rx,
|
||||
(unsigned long)chan);
|
||||
mod_timer(&mbox->rxpoll_timer,
|
||||
jiffies + msecs_to_jiffies(MBOX_POLLING_MS));
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int altera_mbox_send_data(struct mbox_chan *chan, void *data)
|
||||
{
|
||||
struct altera_mbox *mbox = mbox_chan_to_altera_mbox(chan);
|
||||
u32 *udata = (u32 *)data;
|
||||
|
||||
if (!mbox || !data)
|
||||
return -EINVAL;
|
||||
if (!mbox->is_sender) {
|
||||
dev_warn(mbox->dev,
|
||||
"failed to send. This is receiver mailbox.\n");
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
if (altera_mbox_full(mbox))
|
||||
return -EBUSY;
|
||||
|
||||
/* Enable interrupt before send */
|
||||
if (mbox->intr_mode)
|
||||
altera_mbox_tx_intmask(mbox, true);
|
||||
|
||||
/* Pointer register must write before command register */
|
||||
writel_relaxed(udata[MBOX_PTR], mbox->mbox_base + MAILBOX_PTR_REG);
|
||||
writel_relaxed(udata[MBOX_CMD], mbox->mbox_base + MAILBOX_CMD_REG);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static bool altera_mbox_last_tx_done(struct mbox_chan *chan)
|
||||
{
|
||||
struct altera_mbox *mbox = mbox_chan_to_altera_mbox(chan);
|
||||
|
||||
/* Return false if mailbox is full */
|
||||
return altera_mbox_full(mbox) ? false : true;
|
||||
}
|
||||
|
||||
static bool altera_mbox_peek_data(struct mbox_chan *chan)
|
||||
{
|
||||
struct altera_mbox *mbox = mbox_chan_to_altera_mbox(chan);
|
||||
|
||||
return altera_mbox_pending(mbox) ? true : false;
|
||||
}
|
||||
|
||||
static int altera_mbox_startup(struct mbox_chan *chan)
|
||||
{
|
||||
struct altera_mbox *mbox = mbox_chan_to_altera_mbox(chan);
|
||||
int ret = 0;
|
||||
|
||||
if (!mbox)
|
||||
return -EINVAL;
|
||||
|
||||
if (mbox->is_sender)
|
||||
ret = altera_mbox_startup_sender(chan);
|
||||
else
|
||||
ret = altera_mbox_startup_receiver(chan);
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
static void altera_mbox_shutdown(struct mbox_chan *chan)
|
||||
{
|
||||
struct altera_mbox *mbox = mbox_chan_to_altera_mbox(chan);
|
||||
|
||||
if (mbox->intr_mode) {
|
||||
/* Unmask all interrupt masks */
|
||||
writel_relaxed(~0, mbox->mbox_base + MAILBOX_INTMASK_REG);
|
||||
free_irq(mbox->irq, chan);
|
||||
} else if (!mbox->is_sender) {
|
||||
del_timer_sync(&mbox->rxpoll_timer);
|
||||
}
|
||||
}
|
||||
|
||||
static struct mbox_chan_ops altera_mbox_ops = {
|
||||
.send_data = altera_mbox_send_data,
|
||||
.startup = altera_mbox_startup,
|
||||
.shutdown = altera_mbox_shutdown,
|
||||
.last_tx_done = altera_mbox_last_tx_done,
|
||||
.peek_data = altera_mbox_peek_data,
|
||||
};
|
||||
|
||||
static int altera_mbox_probe(struct platform_device *pdev)
|
||||
{
|
||||
struct altera_mbox *mbox;
|
||||
struct resource *regs;
|
||||
struct mbox_chan *chans;
|
||||
int ret;
|
||||
|
||||
mbox = devm_kzalloc(&pdev->dev, sizeof(*mbox),
|
||||
GFP_KERNEL);
|
||||
if (!mbox)
|
||||
return -ENOMEM;
|
||||
|
||||
/* Allocated one channel */
|
||||
chans = devm_kzalloc(&pdev->dev, sizeof(*chans), GFP_KERNEL);
|
||||
if (!chans)
|
||||
return -ENOMEM;
|
||||
|
||||
regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
|
||||
|
||||
mbox->mbox_base = devm_ioremap_resource(&pdev->dev, regs);
|
||||
if (IS_ERR(mbox->mbox_base))
|
||||
return PTR_ERR(mbox->mbox_base);
|
||||
|
||||
/* Check is it a sender or receiver? */
|
||||
mbox->is_sender = altera_mbox_is_sender(mbox);
|
||||
|
||||
mbox->irq = platform_get_irq(pdev, 0);
|
||||
if (mbox->irq >= 0)
|
||||
mbox->intr_mode = true;
|
||||
|
||||
mbox->dev = &pdev->dev;
|
||||
|
||||
/* Hardware supports only one channel. */
|
||||
chans[0].con_priv = mbox;
|
||||
mbox->controller.dev = mbox->dev;
|
||||
mbox->controller.num_chans = 1;
|
||||
mbox->controller.chans = chans;
|
||||
mbox->controller.ops = &altera_mbox_ops;
|
||||
|
||||
if (mbox->is_sender) {
|
||||
if (mbox->intr_mode) {
|
||||
mbox->controller.txdone_irq = true;
|
||||
} else {
|
||||
mbox->controller.txdone_poll = true;
|
||||
mbox->controller.txpoll_period = MBOX_POLLING_MS;
|
||||
}
|
||||
}
|
||||
|
||||
ret = mbox_controller_register(&mbox->controller);
|
||||
if (ret) {
|
||||
dev_err(&pdev->dev, "Register mailbox failed\n");
|
||||
goto err;
|
||||
}
|
||||
|
||||
platform_set_drvdata(pdev, mbox);
|
||||
err:
|
||||
return ret;
|
||||
}
|
||||
|
||||
static int altera_mbox_remove(struct platform_device *pdev)
|
||||
{
|
||||
struct altera_mbox *mbox = platform_get_drvdata(pdev);
|
||||
|
||||
if (!mbox)
|
||||
return -EINVAL;
|
||||
|
||||
mbox_controller_unregister(&mbox->controller);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static const struct of_device_id altera_mbox_match[] = {
|
||||
{ .compatible = "altr,mailbox-1.0" },
|
||||
{ /* Sentinel */ }
|
||||
};
|
||||
|
||||
MODULE_DEVICE_TABLE(of, altera_mbox_match);
|
||||
|
||||
static struct platform_driver altera_mbox_driver = {
|
||||
.probe = altera_mbox_probe,
|
||||
.remove = altera_mbox_remove,
|
||||
.driver = {
|
||||
.name = DRIVER_NAME,
|
||||
.of_match_table = altera_mbox_match,
|
||||
},
|
||||
};
|
||||
|
||||
module_platform_driver(altera_mbox_driver);
|
||||
|
||||
MODULE_LICENSE("GPL v2");
|
||||
MODULE_DESCRIPTION("Altera mailbox specific functions");
|
||||
MODULE_AUTHOR("Ley Foon Tan <lftan@altera.com>");
|
||||
MODULE_ALIAS("platform:altera-mailbox");
|
Загрузка…
Ссылка в новой задаче