| /* |
| * drivers/amlogic/mailbox/meson_mhu.c |
| * |
| * Copyright (C) 2017 Amlogic, Inc. All rights reserved. |
| * |
| * 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. |
| * |
| */ |
| |
| #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
| |
| #include <linux/completion.h> |
| #include <linux/delay.h> |
| #include <linux/err.h> |
| #include <linux/export.h> |
| #include <linux/io.h> |
| #include <linux/interrupt.h> |
| #include <linux/mailbox_controller.h> |
| #include <linux/module.h> |
| #include <linux/mutex.h> |
| #include <linux/notifier.h> |
| #include <linux/platform_device.h> |
| #include <linux/slab.h> |
| #include <linux/spinlock.h> |
| #include <linux/types.h> |
| |
| #include "meson_mhu.h" |
| |
| struct device *the_scpi_device; |
| |
| #define DRIVER_NAME "meson_mhu" |
| |
| /* |
| * +--------------------+-------+---------------+ |
| * | Hardware Register | Offset| Driver View | |
| * +--------------------+-------+---------------+ |
| * | SCP_INTR_L_STAT | 0x014 | RX_STATUS(L) | |
| * | SCP_INTR_L_SET | 0x010 | RX_SET(L) | |
| * | SCP_INTR_L_CLEAR | 0x018 | RX_CLEAR(L) | |
| * +--------------------+-------+---------------+ |
| * | SCP_INTR_H_STAT | 0x020 | RX_STATUS(H) | |
| * | SCP_INTR_H_SET | 0x01c | RX_SET(H) | |
| * | SCP_INTR_H_CLEAR | 0x024 | RX_CLEAR(H) | |
| * +--------------------+-------+---------------+ |
| * | CPU_INTR_L_STAT | 0x038 | TX_STATUS(L) | |
| * | CPU_INTR_L_SET | 0x034 | TX_SET(L) | |
| * | CPU_INTR_L_CLEAR | 0x03c | TX_CLEAR(L) | |
| * +--------------------+-------+---------------+ |
| * | CPU_INTR_H_STAT | 0x044 | TX_STATUS(H) | |
| * | CPU_INTR_H_SET | 0x040 | TX_SET(H) | |
| * | CPU_INTR_H_CLEAR | 0x048 | TX_CLEAR(H) | |
| * +--------------------+-------+---------------+ |
| */ |
| #define RX_OFFSET(chan) (0x10 + (idx) * 0xc) |
| #define RX_STATUS(chan) (RX_OFFSET(chan) + 0x4) |
| #define RX_SET(chan) RX_OFFSET(chan) |
| #define RX_CLEAR(chan) (RX_OFFSET(chan) + 0x8) |
| |
| #define TX_OFFSET(chan) (0x34 + (idx) * 0xc) |
| #define TX_STATUS(chan) (TX_OFFSET(chan) + 0x4) |
| #define TX_SET(chan) TX_OFFSET(chan) |
| #define TX_CLEAR(chan) (TX_OFFSET(chan) + 0x8) |
| |
| /* |
| * +---------------+-------+----------------+ |
| * | Payload | Offset| Driver View | |
| * +---------------+-------+----------------+ |
| * | SCP->AP Low | 0x000 | RX_PAYLOAD(L) | |
| * | SCP->AP High | 0x400 | RX_PAYLOAD(H) | |
| * +---------------+-------+----------------+ |
| * | AP->SCP Low | 0x200 | TX_PAYLOAD(H) | |
| * | AP->SCP High | 0x600 | TX_PAYLOAD(H) | |
| * +---------------+-------+----------------+ |
| */ |
| #define PAYLOAD_MAX_SIZE 0x200 |
| #define PAYLOAD_OFFSET 0x400 |
| #define RX_PAYLOAD(chan) ((chan) * PAYLOAD_OFFSET) |
| #define TX_PAYLOAD(chan) ((chan) * PAYLOAD_OFFSET + PAYLOAD_MAX_SIZE) |
| |
| struct mhu_chan { |
| int index; |
| int rx_irq; |
| struct mhu_ctlr *ctlr; |
| struct mhu_data_buf *data; |
| }; |
| |
| struct mhu_ctlr { |
| struct device *dev; |
| void __iomem *mbox_base; |
| void __iomem *payload_base; |
| struct mbox_controller mbox_con; |
| struct mhu_chan channels[CHANNEL_MAX]; |
| }; |
| |
| static irqreturn_t mbox_handler(int irq, void *p) |
| { |
| struct mbox_chan *link = (struct mbox_chan *)p; |
| struct mhu_chan *chan = link->con_priv; |
| struct mhu_ctlr *ctlr = chan->ctlr; |
| void __iomem *mbox_base = ctlr->mbox_base; |
| void __iomem *payload = ctlr->payload_base; |
| int idx = chan->index; |
| struct mhu_data_buf *data; |
| u32 status = readl(mbox_base + RX_STATUS(idx)); |
| |
| if (status && irq == chan->rx_irq) { |
| data = chan->data; |
| if (!data) |
| return IRQ_NONE; /* spurious */ |
| if (data->rx_buf) |
| memcpy(data->rx_buf, payload + RX_PAYLOAD(idx), |
| data->rx_size); |
| chan->data = NULL; |
| mbox_chan_received_data(link, data); |
| writel(~0, mbox_base + RX_CLEAR(idx)); |
| } |
| |
| return IRQ_HANDLED; |
| } |
| |
| static int mhu_send_data(struct mbox_chan *link, void *msg) |
| { |
| struct mhu_chan *chan = link->con_priv; |
| struct mhu_ctlr *ctlr = chan->ctlr; |
| void __iomem *mbox_base = ctlr->mbox_base; |
| void __iomem *payload = ctlr->payload_base; |
| struct mhu_data_buf *data = (struct mhu_data_buf *)msg; |
| int idx = chan->index; |
| |
| if (!data) |
| return -EINVAL; |
| |
| chan->data = data; |
| if (data->tx_buf) |
| memcpy(payload + TX_PAYLOAD(idx), data->tx_buf, data->tx_size); |
| writel(data->cmd, mbox_base + TX_SET(idx)); |
| |
| return 0; |
| } |
| |
| static int mhu_startup(struct mbox_chan *link) |
| { |
| struct mhu_chan *chan = link->con_priv; |
| int err, mbox_irq = chan->rx_irq; |
| |
| err = request_threaded_irq(mbox_irq, mbox_handler, NULL, IRQF_ONESHOT, |
| DRIVER_NAME, link); |
| return err; |
| } |
| |
| static void mhu_shutdown(struct mbox_chan *link) |
| { |
| struct mhu_chan *chan = link->con_priv; |
| |
| chan->data = NULL; |
| free_irq(chan->rx_irq, link); |
| } |
| |
| static bool mhu_last_tx_done(struct mbox_chan *link) |
| { |
| struct mhu_chan *chan = link->con_priv; |
| struct mhu_ctlr *ctlr = chan->ctlr; |
| void __iomem *mbox_base = ctlr->mbox_base; |
| int idx = chan->index; |
| |
| return !readl(mbox_base + TX_STATUS(idx)); |
| } |
| |
| static struct mbox_chan_ops mhu_ops = { |
| .send_data = mhu_send_data, |
| .startup = mhu_startup, |
| .shutdown = mhu_shutdown, |
| .last_tx_done = mhu_last_tx_done, |
| }; |
| |
| static int mhu_probe(struct platform_device *pdev) |
| { |
| struct mhu_ctlr *ctlr; |
| struct mhu_chan *chan; |
| struct device *dev = &pdev->dev; |
| struct mbox_chan *l; |
| struct resource *res; |
| int idx; |
| static const char * const channel_names[] = { |
| CHANNEL_LOW_PRIORITY, |
| CHANNEL_HIGH_PRIORITY |
| }; |
| |
| ctlr = devm_kzalloc(dev, sizeof(*ctlr), GFP_KERNEL); |
| if (!ctlr) |
| return -ENOMEM; |
| |
| res = platform_get_resource(pdev, IORESOURCE_MEM, 0); |
| if (!res) { |
| dev_err(dev, "failed to get mailbox memory resource\n"); |
| return -ENXIO; |
| } |
| |
| ctlr->mbox_base = devm_ioremap_resource(dev, res); |
| if (IS_ERR(ctlr->mbox_base)) |
| return PTR_ERR(ctlr->mbox_base); |
| |
| res = platform_get_resource(pdev, IORESOURCE_MEM, 1); |
| if (!res) { |
| dev_err(dev, "failed to get payload memory resource\n"); |
| return -ENXIO; |
| } |
| |
| ctlr->payload_base = devm_ioremap_resource(dev, res); |
| if (IS_ERR(ctlr->payload_base)) |
| return PTR_ERR(ctlr->payload_base); |
| |
| ctlr->dev = dev; |
| platform_set_drvdata(pdev, ctlr); |
| |
| l = devm_kzalloc(dev, sizeof(*l) * CHANNEL_MAX, GFP_KERNEL); |
| if (!l) |
| return -ENOMEM; |
| |
| ctlr->mbox_con.chans = l; |
| ctlr->mbox_con.num_chans = CHANNEL_MAX; |
| ctlr->mbox_con.txdone_irq = true; |
| ctlr->mbox_con.ops = &mhu_ops; |
| ctlr->mbox_con.dev = dev; |
| |
| for (idx = 0; idx < CHANNEL_MAX; idx++) { |
| chan = &ctlr->channels[idx]; |
| chan->index = idx; |
| chan->ctlr = ctlr; |
| chan->rx_irq = platform_get_irq(pdev, idx); |
| |
| if (chan->rx_irq < 0) { |
| dev_err(dev, "failed to get interrupt for %s\n", |
| channel_names[idx]); |
| return -ENXIO; |
| } |
| l[idx].con_priv = chan; |
| } |
| |
| if (mbox_controller_register(&ctlr->mbox_con)) { |
| dev_err(dev, "failed to register mailbox controller\n"); |
| return -ENOMEM; |
| } |
| |
| the_scpi_device = dev; |
| return 0; |
| } |
| |
| static int mhu_remove(struct platform_device *pdev) |
| { |
| struct mhu_ctlr *ctlr = platform_get_drvdata(pdev); |
| struct device *dev = &pdev->dev; |
| |
| mbox_controller_unregister(&ctlr->mbox_con); |
| devm_kfree(dev, ctlr->mbox_con.chans); |
| |
| devm_iounmap(dev, ctlr->payload_base); |
| devm_iounmap(dev, ctlr->mbox_base); |
| |
| platform_set_drvdata(pdev, NULL); |
| devm_kfree(dev, ctlr); |
| return 0; |
| } |
| |
| static const struct of_device_id mhu_of_match[] = { |
| { .compatible = "amlogic, meson_mhu" }, |
| {}, |
| }; |
| |
| static struct platform_driver mhu_driver = { |
| .probe = mhu_probe, |
| .remove = mhu_remove, |
| .driver = { |
| .owner = THIS_MODULE, |
| .name = DRIVER_NAME, |
| .of_match_table = mhu_of_match, |
| }, |
| }; |
| |
| static int __init mhu_init(void) |
| { |
| return platform_driver_register(&mhu_driver); |
| } |
| core_initcall(mhu_init); |
| |
| static void __exit mhu_exit(void) |
| { |
| platform_driver_unregister(&mhu_driver); |
| } |
| module_exit(mhu_exit); |
| |
| MODULE_AUTHOR("yan wang <yan.wang@amlogic.com>"); |
| MODULE_DESCRIPTION("MESON MHU mailbox driver"); |
| MODULE_LICENSE("GPL"); |