diff options
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/mailbox/Kconfig | 8 | ||||
| -rw-r--r-- | drivers/mailbox/Makefile | 2 | ||||
| -rw-r--r-- | drivers/mailbox/sprd-mailbox.c | 361 |
3 files changed, 371 insertions, 0 deletions
diff --git a/drivers/mailbox/Kconfig b/drivers/mailbox/Kconfig index 5a577a6734cf..e03f3fb5caed 100644 --- a/drivers/mailbox/Kconfig +++ b/drivers/mailbox/Kconfig @@ -236,4 +236,12 @@ config SUN6I_MSGBOX various Allwinner SoCs. This mailbox is used for communication between the application CPUs and the power management coprocessor. +config SPRD_MBOX + tristate "Spreadtrum Mailbox" + depends on ARCH_SPRD || COMPILE_TEST + help + Mailbox driver implementation for the Spreadtrum platform. It is used + to send message between application processors and MCU. Say Y here if + you want to build the Spreatrum mailbox controller driver. + endif diff --git a/drivers/mailbox/Makefile b/drivers/mailbox/Makefile index 2e4364ef5c47..9caf4ede6ce0 100644 --- a/drivers/mailbox/Makefile +++ b/drivers/mailbox/Makefile @@ -50,3 +50,5 @@ obj-$(CONFIG_MTK_CMDQ_MBOX) += mtk-cmdq-mailbox.o obj-$(CONFIG_ZYNQMP_IPI_MBOX) += zynqmp-ipi-mailbox.o obj-$(CONFIG_SUN6I_MSGBOX) += sun6i-msgbox.o + +obj-$(CONFIG_SPRD_MBOX) += sprd-mailbox.o diff --git a/drivers/mailbox/sprd-mailbox.c b/drivers/mailbox/sprd-mailbox.c new file mode 100644 index 000000000000..f6fab24ae8a9 --- /dev/null +++ b/drivers/mailbox/sprd-mailbox.c @@ -0,0 +1,361 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Spreadtrum mailbox driver + * + * Copyright (c) 2020 Spreadtrum Communications Inc. + */ + +#include <linux/delay.h> +#include <linux/err.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/mailbox_controller.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/clk.h> + +#define SPRD_MBOX_ID 0x0 +#define SPRD_MBOX_MSG_LOW 0x4 +#define SPRD_MBOX_MSG_HIGH 0x8 +#define SPRD_MBOX_TRIGGER 0xc +#define SPRD_MBOX_FIFO_RST 0x10 +#define SPRD_MBOX_FIFO_STS 0x14 +#define SPRD_MBOX_IRQ_STS 0x18 +#define SPRD_MBOX_IRQ_MSK 0x1c +#define SPRD_MBOX_LOCK 0x20 +#define SPRD_MBOX_FIFO_DEPTH 0x24 + +/* Bit and mask definiation for inbox's SPRD_MBOX_FIFO_STS register */ +#define SPRD_INBOX_FIFO_DELIVER_MASK GENMASK(23, 16) +#define SPRD_INBOX_FIFO_OVERLOW_MASK GENMASK(15, 8) +#define SPRD_INBOX_FIFO_DELIVER_SHIFT 16 +#define SPRD_INBOX_FIFO_BUSY_MASK GENMASK(7, 0) + +/* Bit and mask definiation for SPRD_MBOX_IRQ_STS register */ +#define SPRD_MBOX_IRQ_CLR BIT(0) + +/* Bit and mask definiation for outbox's SPRD_MBOX_FIFO_STS register */ +#define SPRD_OUTBOX_FIFO_FULL BIT(0) +#define SPRD_OUTBOX_FIFO_WR_SHIFT 16 +#define SPRD_OUTBOX_FIFO_RD_SHIFT 24 +#define SPRD_OUTBOX_FIFO_POS_MASK GENMASK(7, 0) + +/* Bit and mask definiation for inbox's SPRD_MBOX_IRQ_MSK register */ +#define SPRD_INBOX_FIFO_BLOCK_IRQ BIT(0) +#define SPRD_INBOX_FIFO_OVERFLOW_IRQ BIT(1) +#define SPRD_INBOX_FIFO_DELIVER_IRQ BIT(2) +#define SPRD_INBOX_FIFO_IRQ_MASK GENMASK(2, 0) + +/* Bit and mask definiation for outbox's SPRD_MBOX_IRQ_MSK register */ +#define SPRD_OUTBOX_FIFO_NOT_EMPTY_IRQ BIT(0) +#define SPRD_OUTBOX_FIFO_IRQ_MASK GENMASK(4, 0) + +#define SPRD_MBOX_CHAN_MAX 8 + +struct sprd_mbox_priv { + struct mbox_controller mbox; + struct device *dev; + void __iomem *inbox_base; + void __iomem *outbox_base; + struct clk *clk; + u32 outbox_fifo_depth; + + struct mbox_chan chan[SPRD_MBOX_CHAN_MAX]; +}; + +static struct sprd_mbox_priv *to_sprd_mbox_priv(struct mbox_controller *mbox) +{ + return container_of(mbox, struct sprd_mbox_priv, mbox); +} + +static u32 sprd_mbox_get_fifo_len(struct sprd_mbox_priv *priv, u32 fifo_sts) +{ + u32 wr_pos = (fifo_sts >> SPRD_OUTBOX_FIFO_WR_SHIFT) & + SPRD_OUTBOX_FIFO_POS_MASK; + u32 rd_pos = (fifo_sts >> SPRD_OUTBOX_FIFO_RD_SHIFT) & + SPRD_OUTBOX_FIFO_POS_MASK; + u32 fifo_len; + + /* + * If the read pointer is equal with write pointer, which means the fifo + * is full or empty. + */ + if (wr_pos == rd_pos) { + if (fifo_sts & SPRD_OUTBOX_FIFO_FULL) + fifo_len = priv->outbox_fifo_depth; + else + fifo_len = 0; + } else if (wr_pos > rd_pos) { + fifo_len = wr_pos - rd_pos; + } else { + fifo_len = priv->outbox_fifo_depth - rd_pos + wr_pos; + } + + return fifo_len; +} + +static irqreturn_t sprd_mbox_outbox_isr(int irq, void *data) +{ + struct sprd_mbox_priv *priv = data; + struct mbox_chan *chan; + u32 fifo_sts, fifo_len, msg[2]; + int i, id; + + fifo_sts = readl(priv->outbox_base + SPRD_MBOX_FIFO_STS); + + fifo_len = sprd_mbox_get_fifo_len(priv, fifo_sts); + if (!fifo_len) { + dev_warn_ratelimited(priv->dev, "spurious outbox interrupt\n"); + return IRQ_NONE; + } + + for (i = 0; i < fifo_len; i++) { + msg[0] = readl(priv->outbox_base + SPRD_MBOX_MSG_LOW); + msg[1] = readl(priv->outbox_base + SPRD_MBOX_MSG_HIGH); + id = readl(priv->outbox_base + SPRD_MBOX_ID); + + chan = &priv->chan[id]; + mbox_chan_received_data(chan, (void *)msg); + + /* Trigger to update outbox FIFO pointer */ + writel(0x1, priv->outbox_base + SPRD_MBOX_TRIGGER); + } + + /* Clear irq status after reading all message. */ + writel(SPRD_MBOX_IRQ_CLR, priv->outbox_base + SPRD_MBOX_IRQ_STS); + + return IRQ_HANDLED; +} + +static irqreturn_t sprd_mbox_inbox_isr(int irq, void *data) +{ + struct sprd_mbox_priv *priv = data; + struct mbox_chan *chan; + u32 fifo_sts, send_sts, busy, id; + + fifo_sts = readl(priv->inbox_base + SPRD_MBOX_FIFO_STS); + + /* Get the inbox data delivery status */ + send_sts = (fifo_sts & SPRD_INBOX_FIFO_DELIVER_MASK) >> + SPRD_INBOX_FIFO_DELIVER_SHIFT; + if (!send_sts) { + dev_warn_ratelimited(priv->dev, "spurious inbox interrupt\n"); + return IRQ_NONE; + } + + while (send_sts) { + id = __ffs(send_sts); + send_sts &= (send_sts - 1); + + chan = &priv->chan[id]; + + /* + * Check if the message was fetched by remote traget, if yes, + * that means the transmission has been completed. + */ + busy = fifo_sts & SPRD_INBOX_FIFO_BUSY_MASK; + if (!(busy & BIT(id))) + mbox_chan_txdone(chan, 0); + } + + /* Clear FIFO delivery and overflow status */ + writel(fifo_sts & + (SPRD_INBOX_FIFO_DELIVER_MASK | SPRD_INBOX_FIFO_OVERLOW_MASK), + priv->inbox_base + SPRD_MBOX_FIFO_RST); + + /* Clear irq status */ + writel(SPRD_MBOX_IRQ_CLR, priv->inbox_base + SPRD_MBOX_IRQ_STS); + + return IRQ_HANDLED; +} + +static int sprd_mbox_send_data(struct mbox_chan *chan, void *msg) +{ + struct sprd_mbox_priv *priv = to_sprd_mbox_priv(chan->mbox); + unsigned long id = (unsigned long)chan->con_priv; + u32 *data = msg; + + /* Write data into inbox FIFO, and only support 8 bytes every time */ + writel(data[0], priv->inbox_base + SPRD_MBOX_MSG_LOW); + writel(data[1], priv->inbox_base + SPRD_MBOX_MSG_HIGH); + + /* Set target core id */ + writel(id, priv->inbox_base + SPRD_MBOX_ID); + + /* Trigger remote request */ + writel(0x1, priv->inbox_base + SPRD_MBOX_TRIGGER); + + return 0; +} + +static int sprd_mbox_flush(struct mbox_chan *chan, unsigned long timeout) +{ + struct sprd_mbox_priv *priv = to_sprd_mbox_priv(chan->mbox); + unsigned long id = (unsigned long)chan->con_priv; + u32 busy; + + timeout = jiffies + msecs_to_jiffies(timeout); + + while (time_before(jiffies, timeout)) { + busy = readl(priv->inbox_base + SPRD_MBOX_FIFO_STS) & + SPRD_INBOX_FIFO_BUSY_MASK; + if (!(busy & BIT(id))) { + mbox_chan_txdone(chan, 0); + return 0; + } + + udelay(1); + } + + return -ETIME; +} + +static int sprd_mbox_startup(struct mbox_chan *chan) +{ + struct sprd_mbox_priv *priv = to_sprd_mbox_priv(chan->mbox); + u32 val; + + /* Select outbox FIFO mode and reset the outbox FIFO status */ + writel(0x0, priv->outbox_base + SPRD_MBOX_FIFO_RST); + + /* Enable inbox FIFO overflow and delivery interrupt */ + val = readl(priv->inbox_base + SPRD_MBOX_IRQ_MSK); + val &= ~(SPRD_INBOX_FIFO_OVERFLOW_IRQ | SPRD_INBOX_FIFO_DELIVER_IRQ); + writel(val, priv->inbox_base + SPRD_MBOX_IRQ_MSK); + + /* Enable outbox FIFO not empty interrupt */ + val = readl(priv->outbox_base + SPRD_MBOX_IRQ_MSK); + val &= ~SPRD_OUTBOX_FIFO_NOT_EMPTY_IRQ; + writel(val, priv->outbox_base + SPRD_MBOX_IRQ_MSK); + + return 0; +} + +static void sprd_mbox_shutdown(struct mbox_chan *chan) +{ + struct sprd_mbox_priv *priv = to_sprd_mbox_priv(chan->mbox); + + /* Disable inbox & outbox interrupt */ + writel(SPRD_INBOX_FIFO_IRQ_MASK, priv->inbox_base + SPRD_MBOX_IRQ_MSK); + writel(SPRD_OUTBOX_FIFO_IRQ_MASK, priv->outbox_base + SPRD_MBOX_IRQ_MSK); +} + +static const struct mbox_chan_ops sprd_mbox_ops = { + .send_data = sprd_mbox_send_data, + .flush = sprd_mbox_flush, + .startup = sprd_mbox_startup, + .shutdown = sprd_mbox_shutdown, +}; + +static void sprd_mbox_disable(void *data) +{ + struct sprd_mbox_priv *priv = data; + + clk_disable_unprepare(priv->clk); +} + +static int sprd_mbox_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct sprd_mbox_priv *priv; + int ret, inbox_irq, outbox_irq; + unsigned long id; + + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + priv->dev = dev; + + /* + * The Spreadtrum mailbox uses an inbox to send messages to the target + * core, and uses an outbox to receive messages from other cores. + * + * Thus the mailbox controller supplies 2 different register addresses + * and IRQ numbers for inbox and outbox. + */ + priv->inbox_base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(priv->inbox_base)) + return PTR_ERR(priv->inbox_base); + + priv->outbox_base = devm_platform_ioremap_resource(pdev, 1); + if (IS_ERR(priv->outbox_base)) + return PTR_ERR(priv->outbox_base); + + priv->clk = devm_clk_get(dev, "enable"); + if (IS_ERR(priv->clk)) { + dev_err(dev, "failed to get mailbox clock\n"); + return PTR_ERR(priv->clk); + } + + ret = clk_prepare_enable(priv->clk); + if (ret) + return ret; + + ret = devm_add_action_or_reset(dev, sprd_mbox_disable, priv); + if (ret) { + dev_err(dev, "failed to add mailbox disable action\n"); + return ret; + } + + inbox_irq = platform_get_irq(pdev, 0); + if (inbox_irq < 0) + return inbox_irq; + + ret = devm_request_irq(dev, inbox_irq, sprd_mbox_inbox_isr, + IRQF_NO_SUSPEND, dev_name(dev), priv); + if (ret) { + dev_err(dev, "failed to request inbox IRQ: %d\n", ret); + return ret; + } + + outbox_irq = platform_get_irq(pdev, 1); + if (outbox_irq < 0) + return outbox_irq; + + ret = devm_request_irq(dev, outbox_irq, sprd_mbox_outbox_isr, + IRQF_NO_SUSPEND, dev_name(dev), priv); + if (ret) { + dev_err(dev, "failed to request outbox IRQ: %d\n", ret); + return ret; + } + + /* Get the default outbox FIFO depth */ + priv->outbox_fifo_depth = + readl(priv->outbox_base + SPRD_MBOX_FIFO_DEPTH) + 1; + priv->mbox.dev = dev; + priv->mbox.chans = &priv->chan[0]; + priv->mbox.num_chans = SPRD_MBOX_CHAN_MAX; + priv->mbox.ops = &sprd_mbox_ops; + priv->mbox.txdone_irq = true; + + for (id = 0; id < SPRD_MBOX_CHAN_MAX; id++) + priv->chan[id].con_priv = (void *)id; + + ret = devm_mbox_controller_register(dev, &priv->mbox); + if (ret) { + dev_err(dev, "failed to register mailbox: %d\n", ret); + return ret; + } + + return 0; +} + +static const struct of_device_id sprd_mbox_of_match[] = { + { .compatible = "sprd,sc9860-mailbox", }, + { }, +}; +MODULE_DEVICE_TABLE(of, sprd_mbox_of_match); + +static struct platform_driver sprd_mbox_driver = { + .driver = { + .name = "sprd-mailbox", + .of_match_table = sprd_mbox_of_match, + }, + .probe = sprd_mbox_probe, +}; +module_platform_driver(sprd_mbox_driver); + +MODULE_AUTHOR("Baolin Wang <baolin.wang@unisoc.com>"); +MODULE_DESCRIPTION("Spreadtrum mailbox driver"); +MODULE_LICENSE("GPL v2"); |