--- /dev/null
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2024 Sophgo Technology Inc.
+ * Copyright (C) 2024 Yuntao Dai <d1581209858@live.com>
+ * Copyright (C) 2025 Junhui Liu <junhui.liu@pigmoral.tech>
+ */
+
+#include <linux/bits.h>
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/kfifo.h>
+#include <linux/mailbox_client.h>
+#include <linux/mailbox_controller.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+
+#define RECV_CPU 1
+
+#define MAILBOX_MAX_CHAN 8
+#define MAILBOX_MSG_LEN 8
+
+#define MBOX_EN_REG(cpu) (cpu << 2)
+#define MBOX_DONE_REG(cpu) ((cpu << 2) + 2)
+#define MBOX_SET_CLR_REG(cpu) (0x10 + (cpu << 4))
+#define MBOX_SET_INT_REG(cpu) (0x18 + (cpu << 4))
+#define MBOX_SET_REG 0x60
+
+#define MAILBOX_CONTEXT_OFFSET 0x0400
+#define MAILBOX_CONTEXT_SIZE 0x0040
+
+#define MBOX_CONTEXT_BASE_INDEX(base, index) \
+ ((u64 __iomem *)(base + MAILBOX_CONTEXT_OFFSET) + index)
+
+/**
+ * struct cv1800_mbox_chan_priv - cv1800 mailbox channel private data
+ * @idx: index of channel
+ * @cpu: send to which processor
+ */
+struct cv1800_mbox_chan_priv {
+ int idx;
+ int cpu;
+};
+
+struct cv1800_mbox {
+ struct mbox_controller mbox;
+ struct cv1800_mbox_chan_priv priv[MAILBOX_MAX_CHAN];
+ struct mbox_chan chans[MAILBOX_MAX_CHAN];
+ u64 __iomem *content[MAILBOX_MAX_CHAN];
+ void __iomem *mbox_base;
+ int recvid;
+};
+
+static irqreturn_t cv1800_mbox_isr(int irq, void *dev_id)
+{
+ struct cv1800_mbox *mbox = (struct cv1800_mbox *)dev_id;
+ size_t i;
+ u64 msg;
+ int ret = IRQ_NONE;
+
+ for (i = 0; i < MAILBOX_MAX_CHAN; i++) {
+ if (mbox->content[i] && mbox->chans[i].cl) {
+ memcpy_fromio(&msg, mbox->content[i], MAILBOX_MSG_LEN);
+ mbox->content[i] = NULL;
+ mbox_chan_received_data(&mbox->chans[i], (void *)&msg);
+ ret = IRQ_HANDLED;
+ }
+ }
+
+ return ret;
+}
+
+static irqreturn_t cv1800_mbox_irq(int irq, void *dev_id)
+{
+ struct cv1800_mbox *mbox = (struct cv1800_mbox *)dev_id;
+ u8 set, valid;
+ size_t i;
+ int ret = IRQ_NONE;
+
+ set = readb(mbox->mbox_base + MBOX_SET_INT_REG(RECV_CPU));
+
+ if (!set)
+ return ret;
+
+ for (i = 0; i < MAILBOX_MAX_CHAN; i++) {
+ valid = set & BIT(i);
+ if (valid) {
+ mbox->content[i] =
+ MBOX_CONTEXT_BASE_INDEX(mbox->mbox_base, i);
+ writeb(valid, mbox->mbox_base +
+ MBOX_SET_CLR_REG(RECV_CPU));
+ writeb(~valid, mbox->mbox_base + MBOX_EN_REG(RECV_CPU));
+ ret = IRQ_WAKE_THREAD;
+ }
+ }
+
+ return ret;
+}
+
+static int cv1800_mbox_send_data(struct mbox_chan *chan, void *data)
+{
+ struct cv1800_mbox_chan_priv *priv =
+ (struct cv1800_mbox_chan_priv *)chan->con_priv;
+ struct cv1800_mbox *mbox = dev_get_drvdata(chan->mbox->dev);
+ int idx = priv->idx;
+ int cpu = priv->cpu;
+ u8 en, valid;
+
+ memcpy_toio(MBOX_CONTEXT_BASE_INDEX(mbox->mbox_base, idx),
+ data, MAILBOX_MSG_LEN);
+
+ valid = BIT(idx);
+ writeb(valid, mbox->mbox_base + MBOX_SET_CLR_REG(cpu));
+ en = readb(mbox->mbox_base + MBOX_EN_REG(cpu));
+ writeb(en | valid, mbox->mbox_base + MBOX_EN_REG(cpu));
+ writeb(valid, mbox->mbox_base + MBOX_SET_REG);
+
+ return 0;
+}
+
+static bool cv1800_last_tx_done(struct mbox_chan *chan)
+{
+ struct cv1800_mbox_chan_priv *priv =
+ (struct cv1800_mbox_chan_priv *)chan->con_priv;
+ struct cv1800_mbox *mbox = dev_get_drvdata(chan->mbox->dev);
+ u8 en;
+
+ en = readb(mbox->mbox_base + MBOX_EN_REG(priv->cpu));
+
+ return !(en & BIT(priv->idx));
+}
+
+static const struct mbox_chan_ops cv1800_mbox_chan_ops = {
+ .send_data = cv1800_mbox_send_data,
+ .last_tx_done = cv1800_last_tx_done,
+};
+
+static struct mbox_chan *cv1800_mbox_xlate(struct mbox_controller *mbox,
+ const struct of_phandle_args *spec)
+{
+ struct cv1800_mbox_chan_priv *priv;
+
+ int idx = spec->args[0];
+ int cpu = spec->args[1];
+
+ if (idx >= mbox->num_chans)
+ return ERR_PTR(-EINVAL);
+
+ priv = mbox->chans[idx].con_priv;
+ priv->cpu = cpu;
+
+ return &mbox->chans[idx];
+}
+
+static const struct of_device_id cv1800_mbox_of_match[] = {
+ { .compatible = "sophgo,cv1800b-mailbox", },
+ {},
+};
+MODULE_DEVICE_TABLE(of, cv1800_mbox_of_match);
+
+static int cv1800_mbox_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct cv1800_mbox *mb;
+ int irq, idx, err;
+
+ mb = devm_kzalloc(dev, sizeof(*mb), GFP_KERNEL);
+ if (!mb)
+ return -ENOMEM;
+
+ mb->mbox_base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(mb->mbox_base))
+ return dev_err_probe(dev, PTR_ERR(mb->mbox_base),
+ "Failed to map resource\n");
+
+ mb->mbox.dev = dev;
+ mb->mbox.chans = mb->chans;
+ mb->mbox.txdone_poll = true;
+ mb->mbox.ops = &cv1800_mbox_chan_ops;
+ mb->mbox.num_chans = MAILBOX_MAX_CHAN;
+ mb->mbox.of_xlate = cv1800_mbox_xlate;
+
+ irq = platform_get_irq(pdev, 0);
+ if (irq < 0)
+ return irq;
+
+ err = devm_request_threaded_irq(dev, irq, cv1800_mbox_irq,
+ cv1800_mbox_isr, IRQF_ONESHOT,
+ dev_name(&pdev->dev), mb);
+ if (err < 0)
+ return dev_err_probe(dev, err, "Failed to register irq\n");
+
+ for (idx = 0; idx < MAILBOX_MAX_CHAN; idx++) {
+ mb->priv[idx].idx = idx;
+ mb->mbox.chans[idx].con_priv = &mb->priv[idx];
+ }
+
+ platform_set_drvdata(pdev, mb);
+
+ err = devm_mbox_controller_register(dev, &mb->mbox);
+ if (err)
+ return dev_err_probe(dev, err, "Failed to register mailbox\n");
+
+ return 0;
+}
+
+static struct platform_driver cv1800_mbox_driver = {
+ .driver = {
+ .name = "cv1800-mbox",
+ .of_match_table = cv1800_mbox_of_match,
+ },
+ .probe = cv1800_mbox_probe,
+};
+
+module_platform_driver(cv1800_mbox_driver);
+
+MODULE_DESCRIPTION("cv1800 mailbox driver");
+MODULE_LICENSE("GPL");
projects / thirdparty / linux.git / commitdiff
