drivers/mailbox/cv1800-mailbox.c

Source file repositories/reference/linux-study-clean/drivers/mailbox/cv1800-mailbox.c

File Facts

System
Linux kernel
Corpus path
drivers/mailbox/cv1800-mailbox.c
Extension
.c
Size
5439 bytes
Lines
220
Domain
Driver Families
Bucket
drivers/mailbox
Inferred role
Driver Families: implementation source
Status
source implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

Dependency Surface

Detected Declarations

Annotated Snippet

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));

Annotation

Implementation Notes