linux/drivers/mailbox/imx-mailbox.c

671 lines
16 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (c) 2018 Pengutronix, Oleksij Rempel <o.rempel@pengutronix.de>
*/
#include <linux/clk.h>
#include <linux/firmware/imx/ipc.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/iopoll.h>
#include <linux/kernel.h>
#include <linux/mailbox_controller.h>
#include <linux/module.h>
#include <linux/of_device.h>
#include <linux/pm_runtime.h>
#include <linux/slab.h>
#define IMX_MU_xSR_GIPn(x) BIT(28 + (3 - (x)))
#define IMX_MU_xSR_RFn(x) BIT(24 + (3 - (x)))
#define IMX_MU_xSR_TEn(x) BIT(20 + (3 - (x)))
#define IMX_MU_xSR_BRDIP BIT(9)
/* General Purpose Interrupt Enable */
#define IMX_MU_xCR_GIEn(x) BIT(28 + (3 - (x)))
/* Receive Interrupt Enable */
#define IMX_MU_xCR_RIEn(x) BIT(24 + (3 - (x)))
/* Transmit Interrupt Enable */
#define IMX_MU_xCR_TIEn(x) BIT(20 + (3 - (x)))
/* General Purpose Interrupt Request */
#define IMX_MU_xCR_GIRn(x) BIT(16 + (3 - (x)))
#define IMX_MU_CHANS 16
/* TX0/RX0/RXDB[0-3] */
#define IMX_MU_SCU_CHANS 6
#define IMX_MU_CHAN_NAME_SIZE 20
enum imx_mu_chan_type {
IMX_MU_TYPE_TX, /* Tx */
IMX_MU_TYPE_RX, /* Rx */
IMX_MU_TYPE_TXDB, /* Tx doorbell */
IMX_MU_TYPE_RXDB, /* Rx doorbell */
};
struct imx_sc_rpc_msg_max {
struct imx_sc_rpc_msg hdr;
u32 data[7];
};
struct imx_mu_con_priv {
unsigned int idx;
char irq_desc[IMX_MU_CHAN_NAME_SIZE];
enum imx_mu_chan_type type;
struct mbox_chan *chan;
struct tasklet_struct txdb_tasklet;
};
struct imx_mu_priv {
struct device *dev;
void __iomem *base;
spinlock_t xcr_lock; /* control register lock */
struct mbox_controller mbox;
struct mbox_chan mbox_chans[IMX_MU_CHANS];
struct imx_mu_con_priv con_priv[IMX_MU_CHANS];
const struct imx_mu_dcfg *dcfg;
struct clk *clk;
int irq;
u32 xcr;
bool side_b;
};
struct imx_mu_dcfg {
int (*tx)(struct imx_mu_priv *priv, struct imx_mu_con_priv *cp, void *data);
int (*rx)(struct imx_mu_priv *priv, struct imx_mu_con_priv *cp);
void (*init)(struct imx_mu_priv *priv);
u32 xTR[4]; /* Transmit Registers */
u32 xRR[4]; /* Receive Registers */
u32 xSR; /* Status Register */
u32 xCR; /* Control Register */
};
static struct imx_mu_priv *to_imx_mu_priv(struct mbox_controller *mbox)
{
return container_of(mbox, struct imx_mu_priv, mbox);
}
static void imx_mu_write(struct imx_mu_priv *priv, u32 val, u32 offs)
{
iowrite32(val, priv->base + offs);
}
static u32 imx_mu_read(struct imx_mu_priv *priv, u32 offs)
{
return ioread32(priv->base + offs);
}
static u32 imx_mu_xcr_rmw(struct imx_mu_priv *priv, u32 set, u32 clr)
{
unsigned long flags;
u32 val;
spin_lock_irqsave(&priv->xcr_lock, flags);
val = imx_mu_read(priv, priv->dcfg->xCR);
val &= ~clr;
val |= set;
imx_mu_write(priv, val, priv->dcfg->xCR);
spin_unlock_irqrestore(&priv->xcr_lock, flags);
return val;
}
static int imx_mu_generic_tx(struct imx_mu_priv *priv,
struct imx_mu_con_priv *cp,
void *data)
{
u32 *arg = data;
switch (cp->type) {
case IMX_MU_TYPE_TX:
imx_mu_write(priv, *arg, priv->dcfg->xTR[cp->idx]);
imx_mu_xcr_rmw(priv, IMX_MU_xCR_TIEn(cp->idx), 0);
break;
case IMX_MU_TYPE_TXDB:
imx_mu_xcr_rmw(priv, IMX_MU_xCR_GIRn(cp->idx), 0);
tasklet_schedule(&cp->txdb_tasklet);
break;
default:
dev_warn_ratelimited(priv->dev, "Send data on wrong channel type: %d\n", cp->type);
return -EINVAL;
}
return 0;
}
static int imx_mu_generic_rx(struct imx_mu_priv *priv,
struct imx_mu_con_priv *cp)
{
u32 dat;
dat = imx_mu_read(priv, priv->dcfg->xRR[cp->idx]);
mbox_chan_received_data(cp->chan, (void *)&dat);
return 0;
}
static int imx_mu_scu_tx(struct imx_mu_priv *priv,
struct imx_mu_con_priv *cp,
void *data)
{
struct imx_sc_rpc_msg_max *msg = data;
u32 *arg = data;
int i, ret;
u32 xsr;
switch (cp->type) {
case IMX_MU_TYPE_TX:
/*
* msg->hdr.size specifies the number of u32 words while
* sizeof yields bytes.
*/
if (msg->hdr.size > sizeof(*msg) / 4) {
/*
* The real message size can be different to
* struct imx_sc_rpc_msg_max size
*/
dev_err(priv->dev, "Maximal message size (%zu bytes) exceeded on TX; got: %i bytes\n", sizeof(*msg), msg->hdr.size << 2);
return -EINVAL;
}
for (i = 0; i < 4 && i < msg->hdr.size; i++)
imx_mu_write(priv, *arg++, priv->dcfg->xTR[i % 4]);
for (; i < msg->hdr.size; i++) {
ret = readl_poll_timeout(priv->base + priv->dcfg->xSR,
xsr,
xsr & IMX_MU_xSR_TEn(i % 4),
0, 100);
if (ret) {
dev_err(priv->dev, "Send data index: %d timeout\n", i);
return ret;
}
imx_mu_write(priv, *arg++, priv->dcfg->xTR[i % 4]);
}
imx_mu_xcr_rmw(priv, IMX_MU_xCR_TIEn(cp->idx), 0);
break;
default:
dev_warn_ratelimited(priv->dev, "Send data on wrong channel type: %d\n", cp->type);
return -EINVAL;
}
return 0;
}
static int imx_mu_scu_rx(struct imx_mu_priv *priv,
struct imx_mu_con_priv *cp)
{
struct imx_sc_rpc_msg_max msg;
u32 *data = (u32 *)&msg;
int i, ret;
u32 xsr;
imx_mu_xcr_rmw(priv, 0, IMX_MU_xCR_RIEn(0));
*data++ = imx_mu_read(priv, priv->dcfg->xRR[0]);
if (msg.hdr.size > sizeof(msg) / 4) {
dev_err(priv->dev, "Maximal message size (%zu bytes) exceeded on RX; got: %i bytes\n", sizeof(msg), msg.hdr.size << 2);
return -EINVAL;
}
for (i = 1; i < msg.hdr.size; i++) {
ret = readl_poll_timeout(priv->base + priv->dcfg->xSR, xsr,
xsr & IMX_MU_xSR_RFn(i % 4), 0, 100);
if (ret) {
dev_err(priv->dev, "timeout read idx %d\n", i);
return ret;
}
*data++ = imx_mu_read(priv, priv->dcfg->xRR[i % 4]);
}
imx_mu_xcr_rmw(priv, IMX_MU_xCR_RIEn(0), 0);
mbox_chan_received_data(cp->chan, (void *)&msg);
return 0;
}
static void imx_mu_txdb_tasklet(unsigned long data)
{
struct imx_mu_con_priv *cp = (struct imx_mu_con_priv *)data;
mbox_chan_txdone(cp->chan, 0);
}
static irqreturn_t imx_mu_isr(int irq, void *p)
{
struct mbox_chan *chan = p;
struct imx_mu_priv *priv = to_imx_mu_priv(chan->mbox);
struct imx_mu_con_priv *cp = chan->con_priv;
u32 val, ctrl;
ctrl = imx_mu_read(priv, priv->dcfg->xCR);
val = imx_mu_read(priv, priv->dcfg->xSR);
switch (cp->type) {
case IMX_MU_TYPE_TX:
val &= IMX_MU_xSR_TEn(cp->idx) &
(ctrl & IMX_MU_xCR_TIEn(cp->idx));
break;
case IMX_MU_TYPE_RX:
val &= IMX_MU_xSR_RFn(cp->idx) &
(ctrl & IMX_MU_xCR_RIEn(cp->idx));
break;
case IMX_MU_TYPE_RXDB:
val &= IMX_MU_xSR_GIPn(cp->idx) &
(ctrl & IMX_MU_xCR_GIEn(cp->idx));
break;
default:
break;
}
if (!val)
return IRQ_NONE;
if (val == IMX_MU_xSR_TEn(cp->idx)) {
imx_mu_xcr_rmw(priv, 0, IMX_MU_xCR_TIEn(cp->idx));
mbox_chan_txdone(chan, 0);
} else if (val == IMX_MU_xSR_RFn(cp->idx)) {
priv->dcfg->rx(priv, cp);
} else if (val == IMX_MU_xSR_GIPn(cp->idx)) {
imx_mu_write(priv, IMX_MU_xSR_GIPn(cp->idx), priv->dcfg->xSR);
mbox_chan_received_data(chan, NULL);
} else {
dev_warn_ratelimited(priv->dev, "Not handled interrupt\n");
return IRQ_NONE;
}
return IRQ_HANDLED;
}
static int imx_mu_send_data(struct mbox_chan *chan, void *data)
{
struct imx_mu_priv *priv = to_imx_mu_priv(chan->mbox);
struct imx_mu_con_priv *cp = chan->con_priv;
return priv->dcfg->tx(priv, cp, data);
}
static int imx_mu_startup(struct mbox_chan *chan)
{
struct imx_mu_priv *priv = to_imx_mu_priv(chan->mbox);
struct imx_mu_con_priv *cp = chan->con_priv;
unsigned long irq_flag = IRQF_SHARED;
int ret;
pm_runtime_get_sync(priv->dev);
if (cp->type == IMX_MU_TYPE_TXDB) {
/* Tx doorbell don't have ACK support */
tasklet_init(&cp->txdb_tasklet, imx_mu_txdb_tasklet,
(unsigned long)cp);
return 0;
}
/* IPC MU should be with IRQF_NO_SUSPEND set */
if (!priv->dev->pm_domain)
irq_flag |= IRQF_NO_SUSPEND;
ret = request_irq(priv->irq, imx_mu_isr, irq_flag,
cp->irq_desc, chan);
if (ret) {
dev_err(priv->dev,
"Unable to acquire IRQ %d\n", priv->irq);
return ret;
}
switch (cp->type) {
case IMX_MU_TYPE_RX:
imx_mu_xcr_rmw(priv, IMX_MU_xCR_RIEn(cp->idx), 0);
break;
case IMX_MU_TYPE_RXDB:
imx_mu_xcr_rmw(priv, IMX_MU_xCR_GIEn(cp->idx), 0);
break;
default:
break;
}
return 0;
}
static void imx_mu_shutdown(struct mbox_chan *chan)
{
struct imx_mu_priv *priv = to_imx_mu_priv(chan->mbox);
struct imx_mu_con_priv *cp = chan->con_priv;
if (cp->type == IMX_MU_TYPE_TXDB) {
tasklet_kill(&cp->txdb_tasklet);
pm_runtime_put_sync(priv->dev);
return;
}
switch (cp->type) {
case IMX_MU_TYPE_TX:
imx_mu_xcr_rmw(priv, 0, IMX_MU_xCR_TIEn(cp->idx));
break;
case IMX_MU_TYPE_RX:
imx_mu_xcr_rmw(priv, 0, IMX_MU_xCR_RIEn(cp->idx));
break;
case IMX_MU_TYPE_RXDB:
imx_mu_xcr_rmw(priv, 0, IMX_MU_xCR_GIEn(cp->idx));
break;
default:
break;
}
free_irq(priv->irq, chan);
pm_runtime_put_sync(priv->dev);
}
static const struct mbox_chan_ops imx_mu_ops = {
.send_data = imx_mu_send_data,
.startup = imx_mu_startup,
.shutdown = imx_mu_shutdown,
};
static struct mbox_chan *imx_mu_scu_xlate(struct mbox_controller *mbox,
const struct of_phandle_args *sp)
{
u32 type, idx, chan;
if (sp->args_count != 2) {
dev_err(mbox->dev, "Invalid argument count %d\n", sp->args_count);
return ERR_PTR(-EINVAL);
}
type = sp->args[0]; /* channel type */
idx = sp->args[1]; /* index */
switch (type) {
case IMX_MU_TYPE_TX:
case IMX_MU_TYPE_RX:
if (idx != 0)
dev_err(mbox->dev, "Invalid chan idx: %d\n", idx);
chan = type;
break;
case IMX_MU_TYPE_RXDB:
chan = 2 + idx;
break;
default:
dev_err(mbox->dev, "Invalid chan type: %d\n", type);
return ERR_PTR(-EINVAL);
}
if (chan >= mbox->num_chans) {
dev_err(mbox->dev, "Not supported channel number: %d. (type: %d, idx: %d)\n", chan, type, idx);
return ERR_PTR(-EINVAL);
}
return &mbox->chans[chan];
}
static struct mbox_chan * imx_mu_xlate(struct mbox_controller *mbox,
const struct of_phandle_args *sp)
{
u32 type, idx, chan;
if (sp->args_count != 2) {
dev_err(mbox->dev, "Invalid argument count %d\n", sp->args_count);
return ERR_PTR(-EINVAL);
}
type = sp->args[0]; /* channel type */
idx = sp->args[1]; /* index */
chan = type * 4 + idx;
if (chan >= mbox->num_chans) {
dev_err(mbox->dev, "Not supported channel number: %d. (type: %d, idx: %d)\n", chan, type, idx);
return ERR_PTR(-EINVAL);
}
return &mbox->chans[chan];
}
static void imx_mu_init_generic(struct imx_mu_priv *priv)
{
unsigned int i;
for (i = 0; i < IMX_MU_CHANS; i++) {
struct imx_mu_con_priv *cp = &priv->con_priv[i];
cp->idx = i % 4;
cp->type = i >> 2;
cp->chan = &priv->mbox_chans[i];
priv->mbox_chans[i].con_priv = cp;
snprintf(cp->irq_desc, sizeof(cp->irq_desc),
"imx_mu_chan[%i-%i]", cp->type, cp->idx);
}
priv->mbox.num_chans = IMX_MU_CHANS;
priv->mbox.of_xlate = imx_mu_xlate;
if (priv->side_b)
return;
/* Set default MU configuration */
imx_mu_write(priv, 0, priv->dcfg->xCR);
}
static void imx_mu_init_scu(struct imx_mu_priv *priv)
{
unsigned int i;
for (i = 0; i < IMX_MU_SCU_CHANS; i++) {
struct imx_mu_con_priv *cp = &priv->con_priv[i];
cp->idx = i < 2 ? 0 : i - 2;
cp->type = i < 2 ? i : IMX_MU_TYPE_RXDB;
cp->chan = &priv->mbox_chans[i];
priv->mbox_chans[i].con_priv = cp;
snprintf(cp->irq_desc, sizeof(cp->irq_desc),
"imx_mu_chan[%i-%i]", cp->type, cp->idx);
}
priv->mbox.num_chans = IMX_MU_SCU_CHANS;
priv->mbox.of_xlate = imx_mu_scu_xlate;
/* Set default MU configuration */
imx_mu_write(priv, 0, priv->dcfg->xCR);
}
static int imx_mu_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct device_node *np = dev->of_node;
struct imx_mu_priv *priv;
const struct imx_mu_dcfg *dcfg;
int ret;
priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
if (!priv)
return -ENOMEM;
priv->dev = dev;
priv->base = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(priv->base))
return PTR_ERR(priv->base);
priv->irq = platform_get_irq(pdev, 0);
if (priv->irq < 0)
return priv->irq;
dcfg = of_device_get_match_data(dev);
if (!dcfg)
return -EINVAL;
priv->dcfg = dcfg;
priv->clk = devm_clk_get(dev, NULL);
if (IS_ERR(priv->clk)) {
if (PTR_ERR(priv->clk) != -ENOENT)
return PTR_ERR(priv->clk);
priv->clk = NULL;
}
ret = clk_prepare_enable(priv->clk);
if (ret) {
dev_err(dev, "Failed to enable clock\n");
return ret;
}
priv->side_b = of_property_read_bool(np, "fsl,mu-side-b");
priv->dcfg->init(priv);
spin_lock_init(&priv->xcr_lock);
priv->mbox.dev = dev;
priv->mbox.ops = &imx_mu_ops;
priv->mbox.chans = priv->mbox_chans;
priv->mbox.txdone_irq = true;
platform_set_drvdata(pdev, priv);
ret = devm_mbox_controller_register(dev, &priv->mbox);
if (ret) {
clk_disable_unprepare(priv->clk);
return ret;
}
pm_runtime_enable(dev);
ret = pm_runtime_get_sync(dev);
if (ret < 0) {
pm_runtime_put_noidle(dev);
goto disable_runtime_pm;
}
ret = pm_runtime_put_sync(dev);
if (ret < 0)
goto disable_runtime_pm;
clk_disable_unprepare(priv->clk);
return 0;
disable_runtime_pm:
pm_runtime_disable(dev);
clk_disable_unprepare(priv->clk);
return ret;
}
static int imx_mu_remove(struct platform_device *pdev)
{
struct imx_mu_priv *priv = platform_get_drvdata(pdev);
pm_runtime_disable(priv->dev);
return 0;
}
static const struct imx_mu_dcfg imx_mu_cfg_imx6sx = {
.tx = imx_mu_generic_tx,
.rx = imx_mu_generic_rx,
.init = imx_mu_init_generic,
.xTR = {0x0, 0x4, 0x8, 0xc},
.xRR = {0x10, 0x14, 0x18, 0x1c},
.xSR = 0x20,
.xCR = 0x24,
};
static const struct imx_mu_dcfg imx_mu_cfg_imx7ulp = {
.tx = imx_mu_generic_tx,
.rx = imx_mu_generic_rx,
.init = imx_mu_init_generic,
.xTR = {0x20, 0x24, 0x28, 0x2c},
.xRR = {0x40, 0x44, 0x48, 0x4c},
.xSR = 0x60,
.xCR = 0x64,
};
static const struct imx_mu_dcfg imx_mu_cfg_imx8_scu = {
.tx = imx_mu_scu_tx,
.rx = imx_mu_scu_rx,
.init = imx_mu_init_scu,
.xTR = {0x0, 0x4, 0x8, 0xc},
.xRR = {0x10, 0x14, 0x18, 0x1c},
.xSR = 0x20,
.xCR = 0x24,
};
static const struct of_device_id imx_mu_dt_ids[] = {
{ .compatible = "fsl,imx7ulp-mu", .data = &imx_mu_cfg_imx7ulp },
{ .compatible = "fsl,imx6sx-mu", .data = &imx_mu_cfg_imx6sx },
{ .compatible = "fsl,imx8-mu-scu", .data = &imx_mu_cfg_imx8_scu },
{ },
};
MODULE_DEVICE_TABLE(of, imx_mu_dt_ids);
static int __maybe_unused imx_mu_suspend_noirq(struct device *dev)
{
struct imx_mu_priv *priv = dev_get_drvdata(dev);
if (!priv->clk)
priv->xcr = imx_mu_read(priv, priv->dcfg->xCR);
return 0;
}
static int __maybe_unused imx_mu_resume_noirq(struct device *dev)
{
struct imx_mu_priv *priv = dev_get_drvdata(dev);
/*
* ONLY restore MU when context lost, the TIE could
* be set during noirq resume as there is MU data
* communication going on, and restore the saved
* value will overwrite the TIE and cause MU data
* send failed, may lead to system freeze. This issue
* is observed by testing freeze mode suspend.
*/
if (!imx_mu_read(priv, priv->dcfg->xCR) && !priv->clk)
imx_mu_write(priv, priv->xcr, priv->dcfg->xCR);
return 0;
}
static int __maybe_unused imx_mu_runtime_suspend(struct device *dev)
{
struct imx_mu_priv *priv = dev_get_drvdata(dev);
clk_disable_unprepare(priv->clk);
return 0;
}
static int __maybe_unused imx_mu_runtime_resume(struct device *dev)
{
struct imx_mu_priv *priv = dev_get_drvdata(dev);
int ret;
ret = clk_prepare_enable(priv->clk);
if (ret)
dev_err(dev, "failed to enable clock\n");
return ret;
}
static const struct dev_pm_ops imx_mu_pm_ops = {
SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(imx_mu_suspend_noirq,
imx_mu_resume_noirq)
SET_RUNTIME_PM_OPS(imx_mu_runtime_suspend,
imx_mu_runtime_resume, NULL)
};
static struct platform_driver imx_mu_driver = {
.probe = imx_mu_probe,
.remove = imx_mu_remove,
.driver = {
.name = "imx_mu",
.of_match_table = imx_mu_dt_ids,
.pm = &imx_mu_pm_ops,
},
};
module_platform_driver(imx_mu_driver);
MODULE_AUTHOR("Oleksij Rempel <o.rempel@pengutronix.de>");
MODULE_DESCRIPTION("Message Unit driver for i.MX");
MODULE_LICENSE("GPL v2");