| // SPDX-License-Identifier: GPL-2.0-only |
| /* |
| * Hisilicon's Hi6220 mailbox driver |
| * |
| * Copyright (c) 2015 Hisilicon Limited. |
| * Copyright (c) 2015 Linaro Limited. |
| * |
| * Author: Leo Yan <leo.yan@linaro.org> |
| */ |
| |
| #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 = devm_mbox_controller_register(dev, &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 struct platform_driver hi6220_mbox_driver = { |
| .driver = { |
| .name = "hi6220-mbox", |
| .owner = THIS_MODULE, |
| .of_match_table = hi6220_mbox_of_match, |
| }, |
| .probe = hi6220_mbox_probe, |
| }; |
| |
| 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"); |