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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-23 13:28:57 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-23 13:28:57 -0700 |
| commit | 4352b8aee98005853aa63f57d6377282de17a33f (patch) | |
| tree | 27614d7a9ef05c32d089004e104364ce42324837 /drivers/mailbox/mailbox-altera.c | |
| download | linux-stable-4352b8aee98005853aa63f57d6377282de17a33f.tar.gz linux-stable-4352b8aee98005853aa63f57d6377282de17a33f.zip | |
Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linuxgrafted
Pull I3C updates from Alexandre Belloni:
"A new driver this cycle, for the AMD AXI I3C controller.
There are also new features such as IBI wakeup support, SETAASA device
discovery and ACPI support for the the DAA methods, meaning we can now
communicate with the SPD devices on DDR5 modules.
New driver:
- AMD AXI I3C master controller
Subsystem:
- I3C Common Command Code (CCC) handling improvements, especially
around GET CCCs
- SETAASA device discovery support
- ACPI support for all existing DAA methods like SETDASA, SETNEWDA as
well as I2C devices on I3C bus
- IBI-based wakeup support
Drivers:
- dw: SETAASA support
- mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C
controller support, PIO queue management support for HCI v1.2
- renesas: improve suspend to RAM support, add runtime PM support"
* tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits)
i3c: dw: reduce do_daa time if there's no client
i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller
i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2
i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode
i3c: dw: rename "pclk" to "apb" to match dt-binding
i3c: dw: make struct dw_i3c_cmd smaller
i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding
i3c: renesas: Don't register devices when ENTDAA times out
i3c: master: dw-i3c-master: fix OD timing for first broadcast
i3c: mipi-i3c-hci: Advertise IBI wakeup capability
i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev()
i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI
i3c: master: Reject IBI requests from non-IBI-capable devices
i3c: master: Add helper to query bus wakeup requirements
i3c: master: Report wakeup events for IBIs
i3c: master: Support IBI-based wakeup capability
i3c: master: Fix potential UAF in i3c_device_match()
i3c: master: Fix potential UAF in i3c_device_uevent()
i3c: Make dev->desc locking assumptions explicit
i3c: master: Fix use-after-free of master->this
...
Diffstat (limited to 'drivers/mailbox/mailbox-altera.c')
| -rw-r--r-- | drivers/mailbox/mailbox-altera.c | 361 |
1 files changed, 361 insertions, 0 deletions
diff --git a/drivers/mailbox/mailbox-altera.c b/drivers/mailbox/mailbox-altera.c new file mode 100644 index 000000000..17278c257 --- /dev/null +++ b/drivers/mailbox/mailbox-altera.c @@ -0,0 +1,361 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright Altera Corporation (C) 2013-2014. All rights reserved + */ + +#include <linux/device.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/mailbox_controller.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> + +#define DRIVER_NAME "altera-mailbox" + +#define MAILBOX_CMD_REG 0x00 +#define MAILBOX_PTR_REG 0x04 +#define MAILBOX_STS_REG 0x08 +#define MAILBOX_INTMASK_REG 0x0C + +#define INT_PENDING_MSK 0x1 +#define INT_SPACE_MSK 0x2 + +#define STS_PENDING_MSK 0x1 +#define STS_FULL_MSK 0x2 +#define STS_FULL_OFT 0x1 + +#define MBOX_PENDING(status) (((status) & STS_PENDING_MSK)) +#define MBOX_FULL(status) (((status) & STS_FULL_MSK) >> STS_FULL_OFT) + +enum altera_mbox_msg { + MBOX_CMD = 0, + MBOX_PTR, +}; + +#define MBOX_POLLING_MS 5 /* polling interval 5ms */ + +struct altera_mbox { + bool is_sender; /* 1-sender, 0-receiver */ + bool intr_mode; + int irq; + void __iomem *mbox_base; + struct device *dev; + struct mbox_controller controller; + + /* If the controller supports only RX polling mode */ + struct timer_list rxpoll_timer; + struct mbox_chan *chan; +}; + +static struct altera_mbox *mbox_chan_to_altera_mbox(struct mbox_chan *chan) +{ + if (!chan || !chan->con_priv) + return NULL; + + return (struct altera_mbox *)chan->con_priv; +} + +static inline int altera_mbox_full(struct altera_mbox *mbox) +{ + u32 status; + + status = readl_relaxed(mbox->mbox_base + MAILBOX_STS_REG); + return MBOX_FULL(status); +} + +static inline int altera_mbox_pending(struct altera_mbox *mbox) +{ + u32 status; + + status = readl_relaxed(mbox->mbox_base + MAILBOX_STS_REG); + return MBOX_PENDING(status); +} + +static void altera_mbox_rx_intmask(struct altera_mbox *mbox, bool enable) +{ + u32 mask; + + mask = readl_relaxed(mbox->mbox_base + MAILBOX_INTMASK_REG); + if (enable) + mask |= INT_PENDING_MSK; + else + mask &= ~INT_PENDING_MSK; + writel_relaxed(mask, mbox->mbox_base + MAILBOX_INTMASK_REG); +} + +static void altera_mbox_tx_intmask(struct altera_mbox *mbox, bool enable) +{ + u32 mask; + + mask = readl_relaxed(mbox->mbox_base + MAILBOX_INTMASK_REG); + if (enable) + mask |= INT_SPACE_MSK; + else + mask &= ~INT_SPACE_MSK; + writel_relaxed(mask, mbox->mbox_base + MAILBOX_INTMASK_REG); +} + +static bool altera_mbox_is_sender(struct altera_mbox *mbox) +{ + u32 reg; + /* Write a magic number to PTR register and read back this register. + * This register is read-write if it is a sender. + */ + #define MBOX_MAGIC 0xA5A5AA55 + writel_relaxed(MBOX_MAGIC, mbox->mbox_base + MAILBOX_PTR_REG); + reg = readl_relaxed(mbox->mbox_base + MAILBOX_PTR_REG); + if (reg == MBOX_MAGIC) { + /* Clear to 0 */ + writel_relaxed(0, mbox->mbox_base + MAILBOX_PTR_REG); + return true; + } + return false; +} + +static void altera_mbox_rx_data(struct mbox_chan *chan) +{ + struct altera_mbox *mbox = mbox_chan_to_altera_mbox(chan); + u32 data[2]; + + if (altera_mbox_pending(mbox)) { + data[MBOX_PTR] = + readl_relaxed(mbox->mbox_base + MAILBOX_PTR_REG); + data[MBOX_CMD] = + readl_relaxed(mbox->mbox_base + MAILBOX_CMD_REG); + mbox_chan_received_data(chan, (void *)data); + } +} + +static void altera_mbox_poll_rx(struct timer_list *t) +{ + struct altera_mbox *mbox = timer_container_of(mbox, t, rxpoll_timer); + + altera_mbox_rx_data(mbox->chan); + + mod_timer(&mbox->rxpoll_timer, + jiffies + msecs_to_jiffies(MBOX_POLLING_MS)); +} + +static irqreturn_t altera_mbox_tx_interrupt(int irq, void *p) +{ + struct mbox_chan *chan = (struct mbox_chan *)p; + struct altera_mbox *mbox = mbox_chan_to_altera_mbox(chan); + + altera_mbox_tx_intmask(mbox, false); + mbox_chan_txdone(chan, 0); + + return IRQ_HANDLED; +} + +static irqreturn_t altera_mbox_rx_interrupt(int irq, void *p) +{ + struct mbox_chan *chan = (struct mbox_chan *)p; + + altera_mbox_rx_data(chan); + return IRQ_HANDLED; +} + +static int altera_mbox_startup_sender(struct mbox_chan *chan) +{ + int ret; + struct altera_mbox *mbox = mbox_chan_to_altera_mbox(chan); + + if (mbox->intr_mode) { + ret = request_irq(mbox->irq, altera_mbox_tx_interrupt, 0, + DRIVER_NAME, chan); + if (unlikely(ret)) { + dev_err(mbox->dev, + "failed to register mailbox interrupt:%d\n", + ret); + return ret; + } + } + + return 0; +} + +static int altera_mbox_startup_receiver(struct mbox_chan *chan) +{ + int ret; + struct altera_mbox *mbox = mbox_chan_to_altera_mbox(chan); + + if (mbox->intr_mode) { + ret = request_irq(mbox->irq, altera_mbox_rx_interrupt, 0, + DRIVER_NAME, chan); + if (unlikely(ret)) { + mbox->intr_mode = false; + goto polling; /* use polling if failed */ + } + + altera_mbox_rx_intmask(mbox, true); + return 0; + } + +polling: + /* Setup polling timer */ + mbox->chan = chan; + timer_setup(&mbox->rxpoll_timer, altera_mbox_poll_rx, 0); + mod_timer(&mbox->rxpoll_timer, + jiffies + msecs_to_jiffies(MBOX_POLLING_MS)); + + return 0; +} + +static int altera_mbox_send_data(struct mbox_chan *chan, void *data) +{ + struct altera_mbox *mbox = mbox_chan_to_altera_mbox(chan); + u32 *udata = (u32 *)data; + + if (!mbox || !data) + return -EINVAL; + if (!mbox->is_sender) { + dev_warn(mbox->dev, + "failed to send. This is receiver mailbox.\n"); + return -EINVAL; + } + + if (altera_mbox_full(mbox)) + return -EBUSY; + + /* Enable interrupt before send */ + if (mbox->intr_mode) + altera_mbox_tx_intmask(mbox, true); + + /* Pointer register must write before command register */ + writel_relaxed(udata[MBOX_PTR], mbox->mbox_base + MAILBOX_PTR_REG); + writel_relaxed(udata[MBOX_CMD], mbox->mbox_base + MAILBOX_CMD_REG); + + return 0; +} + +static bool altera_mbox_last_tx_done(struct mbox_chan *chan) +{ + struct altera_mbox *mbox = mbox_chan_to_altera_mbox(chan); + + /* Return false if mailbox is full */ + return altera_mbox_full(mbox) ? false : true; +} + +static bool altera_mbox_peek_data(struct mbox_chan *chan) +{ + struct altera_mbox *mbox = mbox_chan_to_altera_mbox(chan); + + return altera_mbox_pending(mbox) ? true : false; +} + +static int altera_mbox_startup(struct mbox_chan *chan) +{ + struct altera_mbox *mbox = mbox_chan_to_altera_mbox(chan); + int ret = 0; + + if (!mbox) + return -EINVAL; + + if (mbox->is_sender) + ret = altera_mbox_startup_sender(chan); + else + ret = altera_mbox_startup_receiver(chan); + + return ret; +} + +static void altera_mbox_shutdown(struct mbox_chan *chan) +{ + struct altera_mbox *mbox = mbox_chan_to_altera_mbox(chan); + + if (mbox->intr_mode) { + /* Unmask all interrupt masks */ + writel_relaxed(~0, mbox->mbox_base + MAILBOX_INTMASK_REG); + free_irq(mbox->irq, chan); + } else if (!mbox->is_sender) { + timer_delete_sync(&mbox->rxpoll_timer); + } +} + +static const struct mbox_chan_ops altera_mbox_ops = { + .send_data = altera_mbox_send_data, + .startup = altera_mbox_startup, + .shutdown = altera_mbox_shutdown, + .last_tx_done = altera_mbox_last_tx_done, + .peek_data = altera_mbox_peek_data, +}; + +static int altera_mbox_probe(struct platform_device *pdev) +{ + struct altera_mbox *mbox; + struct mbox_chan *chans; + int ret; + + mbox = devm_kzalloc(&pdev->dev, sizeof(*mbox), + GFP_KERNEL); + if (!mbox) + return -ENOMEM; + + /* Allocated one channel */ + chans = devm_kzalloc(&pdev->dev, sizeof(*chans), GFP_KERNEL); + if (!chans) + return -ENOMEM; + + mbox->mbox_base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(mbox->mbox_base)) + return PTR_ERR(mbox->mbox_base); + + /* Check is it a sender or receiver? */ + mbox->is_sender = altera_mbox_is_sender(mbox); + + mbox->irq = platform_get_irq(pdev, 0); + if (mbox->irq >= 0) + mbox->intr_mode = true; + + mbox->dev = &pdev->dev; + + /* Hardware supports only one channel. */ + chans[0].con_priv = mbox; + mbox->controller.dev = mbox->dev; + mbox->controller.num_chans = 1; + mbox->controller.chans = chans; + mbox->controller.ops = &altera_mbox_ops; + + if (mbox->is_sender) { + if (mbox->intr_mode) { + mbox->controller.txdone_irq = true; + } else { + mbox->controller.txdone_poll = true; + mbox->controller.txpoll_period = MBOX_POLLING_MS; + } + } + + ret = devm_mbox_controller_register(&pdev->dev, &mbox->controller); + if (ret) { + dev_err(&pdev->dev, "Register mailbox failed\n"); + goto err; + } + + platform_set_drvdata(pdev, mbox); +err: + return ret; +} + +static const struct of_device_id altera_mbox_match[] = { + { .compatible = "altr,mailbox-1.0" }, + { /* Sentinel */ } +}; + +MODULE_DEVICE_TABLE(of, altera_mbox_match); + +static struct platform_driver altera_mbox_driver = { + .probe = altera_mbox_probe, + .driver = { + .name = DRIVER_NAME, + .of_match_table = altera_mbox_match, + }, +}; + +module_platform_driver(altera_mbox_driver); + +MODULE_LICENSE("GPL v2"); +MODULE_DESCRIPTION("Altera mailbox specific functions"); +MODULE_AUTHOR("Ley Foon Tan <lftan@altera.com>"); +MODULE_ALIAS("platform:altera-mailbox"); |
