diff options
Diffstat (limited to 'drivers/mailbox/hi6220-mailbox.c')
| -rw-r--r-- | drivers/mailbox/hi6220-mailbox.c | 395 |
1 files changed, 395 insertions, 0 deletions
diff --git a/drivers/mailbox/hi6220-mailbox.c b/drivers/mailbox/hi6220-mailbox.c new file mode 100644 index 000000000..4fa9803cd --- /dev/null +++ b/drivers/mailbox/hi6220-mailbox.c @@ -0,0 +1,395 @@ +/* + * Hisilicon's Hi6220 mailbox driver + * + * Copyright (c) 2015 Hisilicon Limited. + * Copyright (c) 2015 Linaro Limited. + * + * Author: Leo Yan <leo.yan@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, version 2 of the License. + * + * 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. + * + */ + +#include <linux/device.h> +#include <linux/err.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/kfifo.h> +#include <linux/mailbox_controller.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/slab.h> + +#define MBOX_CHAN_MAX 32 + +#define MBOX_TX 0x1 + +/* Mailbox message length: 8 words */ +#define MBOX_MSG_LEN 8 + +/* Mailbox Registers */ +#define MBOX_OFF(m) (0x40 * (m)) +#define MBOX_MODE_REG(m) (MBOX_OFF(m) + 0x0) +#define MBOX_DATA_REG(m) (MBOX_OFF(m) + 0x4) + +#define MBOX_STATE_MASK (0xF << 4) +#define MBOX_STATE_IDLE (0x1 << 4) +#define MBOX_STATE_TX (0x2 << 4) +#define MBOX_STATE_RX (0x4 << 4) +#define MBOX_STATE_ACK (0x8 << 4) +#define MBOX_ACK_CONFIG_MASK (0x1 << 0) +#define MBOX_ACK_AUTOMATIC (0x1 << 0) +#define MBOX_ACK_IRQ (0x0 << 0) + +/* IPC registers */ +#define ACK_INT_RAW_REG(i) ((i) + 0x400) +#define ACK_INT_MSK_REG(i) ((i) + 0x404) +#define ACK_INT_STAT_REG(i) ((i) + 0x408) +#define ACK_INT_CLR_REG(i) ((i) + 0x40c) +#define ACK_INT_ENA_REG(i) ((i) + 0x500) +#define ACK_INT_DIS_REG(i) ((i) + 0x504) +#define DST_INT_RAW_REG(i) ((i) + 0x420) + + +struct hi6220_mbox_chan { + + /* + * Description for channel's hardware info: + * - direction: tx or rx + * - dst irq: peer core's irq number + * - ack irq: local irq number + * - slot number + */ + unsigned int dir, dst_irq, ack_irq; + unsigned int slot; + + struct hi6220_mbox *parent; +}; + +struct hi6220_mbox { + struct device *dev; + + int irq; + + /* flag of enabling tx's irq mode */ + bool tx_irq_mode; + + /* region for ipc event */ + void __iomem *ipc; + + /* region for mailbox */ + void __iomem *base; + + unsigned int chan_num; + struct hi6220_mbox_chan *mchan; + + void *irq_map_chan[MBOX_CHAN_MAX]; + struct mbox_chan *chan; + struct mbox_controller controller; +}; + +static void mbox_set_state(struct hi6220_mbox *mbox, + unsigned int slot, u32 val) +{ + u32 status; + + status = readl(mbox->base + MBOX_MODE_REG(slot)); + status = (status & ~MBOX_STATE_MASK) | val; + writel(status, mbox->base + MBOX_MODE_REG(slot)); +} + +static void mbox_set_mode(struct hi6220_mbox *mbox, + unsigned int slot, u32 val) +{ + u32 mode; + + mode = readl(mbox->base + MBOX_MODE_REG(slot)); + mode = (mode & ~MBOX_ACK_CONFIG_MASK) | val; + writel(mode, mbox->base + MBOX_MODE_REG(slot)); +} + +static bool hi6220_mbox_last_tx_done(struct mbox_chan *chan) +{ + struct hi6220_mbox_chan *mchan = chan->con_priv; + struct hi6220_mbox *mbox = mchan->parent; + u32 state; + + /* Only set idle state for polling mode */ + BUG_ON(mbox->tx_irq_mode); + + state = readl(mbox->base + MBOX_MODE_REG(mchan->slot)); + return ((state & MBOX_STATE_MASK) == MBOX_STATE_IDLE); +} + +static int hi6220_mbox_send_data(struct mbox_chan *chan, void *msg) +{ + struct hi6220_mbox_chan *mchan = chan->con_priv; + struct hi6220_mbox *mbox = mchan->parent; + unsigned int slot = mchan->slot; + u32 *buf = msg; + int i; + + /* indicate as a TX channel */ + mchan->dir = MBOX_TX; + + mbox_set_state(mbox, slot, MBOX_STATE_TX); + + if (mbox->tx_irq_mode) + mbox_set_mode(mbox, slot, MBOX_ACK_IRQ); + else + mbox_set_mode(mbox, slot, MBOX_ACK_AUTOMATIC); + + for (i = 0; i < MBOX_MSG_LEN; i++) + writel(buf[i], mbox->base + MBOX_DATA_REG(slot) + i * 4); + + /* trigger remote request */ + writel(BIT(mchan->dst_irq), DST_INT_RAW_REG(mbox->ipc)); + return 0; +} + +static irqreturn_t hi6220_mbox_interrupt(int irq, void *p) +{ + struct hi6220_mbox *mbox = p; + struct hi6220_mbox_chan *mchan; + struct mbox_chan *chan; + unsigned int state, intr_bit, i; + u32 msg[MBOX_MSG_LEN]; + + state = readl(ACK_INT_STAT_REG(mbox->ipc)); + if (!state) { + dev_warn(mbox->dev, "%s: spurious interrupt\n", + __func__); + return IRQ_HANDLED; + } + + while (state) { + intr_bit = __ffs(state); + state &= (state - 1); + + chan = mbox->irq_map_chan[intr_bit]; + if (!chan) { + dev_warn(mbox->dev, "%s: unexpected irq vector %d\n", + __func__, intr_bit); + continue; + } + + mchan = chan->con_priv; + if (mchan->dir == MBOX_TX) + mbox_chan_txdone(chan, 0); + else { + for (i = 0; i < MBOX_MSG_LEN; i++) + msg[i] = readl(mbox->base + + MBOX_DATA_REG(mchan->slot) + i * 4); + + mbox_chan_received_data(chan, (void *)msg); + } + + /* clear IRQ source */ + writel(BIT(mchan->ack_irq), ACK_INT_CLR_REG(mbox->ipc)); + mbox_set_state(mbox, mchan->slot, MBOX_STATE_IDLE); + } + + return IRQ_HANDLED; +} + +static int hi6220_mbox_startup(struct mbox_chan *chan) +{ + struct hi6220_mbox_chan *mchan = chan->con_priv; + struct hi6220_mbox *mbox = mchan->parent; + + mchan->dir = 0; + + /* enable interrupt */ + writel(BIT(mchan->ack_irq), ACK_INT_ENA_REG(mbox->ipc)); + return 0; +} + +static void hi6220_mbox_shutdown(struct mbox_chan *chan) +{ + struct hi6220_mbox_chan *mchan = chan->con_priv; + struct hi6220_mbox *mbox = mchan->parent; + + /* disable interrupt */ + writel(BIT(mchan->ack_irq), ACK_INT_DIS_REG(mbox->ipc)); + mbox->irq_map_chan[mchan->ack_irq] = NULL; +} + +static const struct mbox_chan_ops hi6220_mbox_ops = { + .send_data = hi6220_mbox_send_data, + .startup = hi6220_mbox_startup, + .shutdown = hi6220_mbox_shutdown, + .last_tx_done = hi6220_mbox_last_tx_done, +}; + +static struct mbox_chan *hi6220_mbox_xlate(struct mbox_controller *controller, + const struct of_phandle_args *spec) +{ + struct hi6220_mbox *mbox = dev_get_drvdata(controller->dev); + struct hi6220_mbox_chan *mchan; + struct mbox_chan *chan; + unsigned int i = spec->args[0]; + unsigned int dst_irq = spec->args[1]; + unsigned int ack_irq = spec->args[2]; + + /* Bounds checking */ + if (i >= mbox->chan_num || dst_irq >= mbox->chan_num || + ack_irq >= mbox->chan_num) { + dev_err(mbox->dev, + "Invalid channel idx %d dst_irq %d ack_irq %d\n", + i, dst_irq, ack_irq); + return ERR_PTR(-EINVAL); + } + + /* Is requested channel free? */ + chan = &mbox->chan[i]; + if (mbox->irq_map_chan[ack_irq] == (void *)chan) { + dev_err(mbox->dev, "Channel in use\n"); + return ERR_PTR(-EBUSY); + } + + mchan = chan->con_priv; + mchan->dst_irq = dst_irq; + mchan->ack_irq = ack_irq; + + mbox->irq_map_chan[ack_irq] = (void *)chan; + return chan; +} + +static const struct of_device_id hi6220_mbox_of_match[] = { + { .compatible = "hisilicon,hi6220-mbox", }, + {}, +}; +MODULE_DEVICE_TABLE(of, hi6220_mbox_of_match); + +static int hi6220_mbox_probe(struct platform_device *pdev) +{ + struct device_node *node = pdev->dev.of_node; + struct device *dev = &pdev->dev; + struct hi6220_mbox *mbox; + struct resource *res; + int i, err; + + mbox = devm_kzalloc(dev, sizeof(*mbox), GFP_KERNEL); + if (!mbox) + return -ENOMEM; + + mbox->dev = dev; + mbox->chan_num = MBOX_CHAN_MAX; + mbox->mchan = devm_kcalloc(dev, + mbox->chan_num, sizeof(*mbox->mchan), GFP_KERNEL); + if (!mbox->mchan) + return -ENOMEM; + + mbox->chan = devm_kcalloc(dev, + mbox->chan_num, sizeof(*mbox->chan), GFP_KERNEL); + if (!mbox->chan) + return -ENOMEM; + + mbox->irq = platform_get_irq(pdev, 0); + if (mbox->irq < 0) + return mbox->irq; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + mbox->ipc = devm_ioremap_resource(dev, res); + if (IS_ERR(mbox->ipc)) { + dev_err(dev, "ioremap ipc failed\n"); + return PTR_ERR(mbox->ipc); + } + + res = platform_get_resource(pdev, IORESOURCE_MEM, 1); + mbox->base = devm_ioremap_resource(dev, res); + if (IS_ERR(mbox->base)) { + dev_err(dev, "ioremap buffer failed\n"); + return PTR_ERR(mbox->base); + } + + err = devm_request_irq(dev, mbox->irq, hi6220_mbox_interrupt, 0, + dev_name(dev), mbox); + if (err) { + dev_err(dev, "Failed to register a mailbox IRQ handler: %d\n", + err); + return -ENODEV; + } + + mbox->controller.dev = dev; + mbox->controller.chans = &mbox->chan[0]; + mbox->controller.num_chans = mbox->chan_num; + mbox->controller.ops = &hi6220_mbox_ops; + mbox->controller.of_xlate = hi6220_mbox_xlate; + + for (i = 0; i < mbox->chan_num; i++) { + mbox->chan[i].con_priv = &mbox->mchan[i]; + mbox->irq_map_chan[i] = NULL; + + mbox->mchan[i].parent = mbox; + mbox->mchan[i].slot = i; + } + + /* mask and clear all interrupt vectors */ + writel(0x0, ACK_INT_MSK_REG(mbox->ipc)); + writel(~0x0, ACK_INT_CLR_REG(mbox->ipc)); + + /* use interrupt for tx's ack */ + if (of_find_property(node, "hi6220,mbox-tx-noirq", NULL)) + mbox->tx_irq_mode = false; + else + mbox->tx_irq_mode = true; + + if (mbox->tx_irq_mode) + mbox->controller.txdone_irq = true; + else { + mbox->controller.txdone_poll = true; + mbox->controller.txpoll_period = 5; + } + + err = mbox_controller_register(&mbox->controller); + if (err) { + dev_err(dev, "Failed to register mailbox %d\n", err); + return err; + } + + platform_set_drvdata(pdev, mbox); + dev_info(dev, "Mailbox enabled\n"); + return 0; +} + +static int hi6220_mbox_remove(struct platform_device *pdev) +{ + struct hi6220_mbox *mbox = platform_get_drvdata(pdev); + + mbox_controller_unregister(&mbox->controller); + return 0; +} + +static struct platform_driver hi6220_mbox_driver = { + .driver = { + .name = "hi6220-mbox", + .owner = THIS_MODULE, + .of_match_table = hi6220_mbox_of_match, + }, + .probe = hi6220_mbox_probe, + .remove = hi6220_mbox_remove, +}; + +static int __init hi6220_mbox_init(void) +{ + return platform_driver_register(&hi6220_mbox_driver); +} +core_initcall(hi6220_mbox_init); + +static void __exit hi6220_mbox_exit(void) +{ + platform_driver_unregister(&hi6220_mbox_driver); +} +module_exit(hi6220_mbox_exit); + +MODULE_AUTHOR("Leo Yan <leo.yan@linaro.org>"); +MODULE_DESCRIPTION("Hi6220 mailbox driver"); +MODULE_LICENSE("GPL v2"); |