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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-mpfs.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-mpfs.c')
| -rw-r--r-- | drivers/mailbox/mailbox-mpfs.c | 339 |
1 files changed, 339 insertions, 0 deletions
diff --git a/drivers/mailbox/mailbox-mpfs.c b/drivers/mailbox/mailbox-mpfs.c new file mode 100644 index 000000000..6c40d865b --- /dev/null +++ b/drivers/mailbox/mailbox-mpfs.c @@ -0,0 +1,339 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Microchip PolarFire SoC (MPFS) system controller/mailbox controller driver + * + * Copyright (c) 2020-2022 Microchip Corporation. All rights reserved. + * + * Author: Conor Dooley <conor.dooley@microchip.com> + * + */ + +#include <linux/io.h> +#include <linux/err.h> +#include <linux/init.h> +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/regmap.h> +#include <linux/interrupt.h> +#include <linux/mfd/syscon.h> +#include <linux/platform_device.h> +#include <linux/mailbox_controller.h> +#include <soc/microchip/mpfs.h> + +#define MESSAGE_INT_OFFSET 0x18cu +#define SERVICES_CR_OFFSET 0x50u +#define SERVICES_SR_OFFSET 0x54u +#define MAILBOX_REG_OFFSET 0x800u +#define MSS_SYS_MAILBOX_DATA_OFFSET 0u +#define SCB_MASK_WIDTH 16u + +/* SCBCTRL service control register */ + +#define SCB_CTRL_REQ (0) +#define SCB_CTRL_REQ_MASK BIT(SCB_CTRL_REQ) + +#define SCB_CTRL_BUSY (1) +#define SCB_CTRL_BUSY_MASK BIT(SCB_CTRL_BUSY) + +#define SCB_CTRL_ABORT (2) +#define SCB_CTRL_ABORT_MASK BIT(SCB_CTRL_ABORT) + +#define SCB_CTRL_NOTIFY (3) +#define SCB_CTRL_NOTIFY_MASK BIT(SCB_CTRL_NOTIFY) + +#define SCB_CTRL_POS (16) +#define SCB_CTRL_MASK GENMASK(SCB_CTRL_POS + SCB_MASK_WIDTH - 1, SCB_CTRL_POS) + +/* SCBCTRL service status register */ + +#define SCB_STATUS_REQ (0) +#define SCB_STATUS_REQ_MASK BIT(SCB_STATUS_REQ) + +#define SCB_STATUS_BUSY (1) +#define SCB_STATUS_BUSY_MASK BIT(SCB_STATUS_BUSY) + +#define SCB_STATUS_ABORT (2) +#define SCB_STATUS_ABORT_MASK BIT(SCB_STATUS_ABORT) + +#define SCB_STATUS_NOTIFY (3) +#define SCB_STATUS_NOTIFY_MASK BIT(SCB_STATUS_NOTIFY) + +#define SCB_STATUS_POS (16) +#define SCB_STATUS_MASK GENMASK(SCB_STATUS_POS + SCB_MASK_WIDTH - 1, SCB_STATUS_POS) + +struct mpfs_mbox { + struct mbox_controller controller; + struct device *dev; + int irq; + void __iomem *ctrl_base; + void __iomem *mbox_base; + void __iomem *int_reg; + struct mbox_chan chans[1]; + struct mpfs_mss_response *response; + struct regmap *sysreg_scb, *control_scb; + u16 resp_offset; +}; + +static bool mpfs_mbox_busy(struct mpfs_mbox *mbox) +{ + u32 status; + + if (mbox->control_scb) + regmap_read(mbox->control_scb, SERVICES_SR_OFFSET, &status); + else + status = readl_relaxed(mbox->ctrl_base + SERVICES_SR_OFFSET); + + return status & SCB_STATUS_BUSY_MASK; +} + +static bool mpfs_mbox_last_tx_done(struct mbox_chan *chan) +{ + struct mpfs_mbox *mbox = (struct mpfs_mbox *)chan->con_priv; + struct mpfs_mss_response *response = mbox->response; + u32 val; + + if (mpfs_mbox_busy(mbox)) + return false; + + /* + * The service status is stored in bits 31:16 of the SERVICES_SR + * register & is only valid when the system controller is not busy. + * Failed services are intended to generated interrupts, but in reality + * this does not happen, so the status must be checked here. + */ + if (mbox->control_scb) + regmap_read(mbox->control_scb, SERVICES_SR_OFFSET, &val); + else + val = readl_relaxed(mbox->ctrl_base + SERVICES_SR_OFFSET); + + response->resp_status = (val & SCB_STATUS_MASK) >> SCB_STATUS_POS; + + return true; +} + +static int mpfs_mbox_send_data(struct mbox_chan *chan, void *data) +{ + struct mpfs_mbox *mbox = (struct mpfs_mbox *)chan->con_priv; + struct mpfs_mss_msg *msg = data; + u32 tx_trigger; + u16 opt_sel; + u32 val = 0u; + + mbox->response = msg->response; + mbox->resp_offset = msg->resp_offset; + + if (mpfs_mbox_busy(mbox)) + return -EBUSY; + + if (msg->cmd_data_size) { + u32 index; + u8 extra_bits = msg->cmd_data_size & 3; + u32 *word_buf = (u32 *)msg->cmd_data; + + for (index = 0; index < (msg->cmd_data_size / 4); index++) + writel_relaxed(word_buf[index], + mbox->mbox_base + msg->mbox_offset + index * 0x4); + if (extra_bits) { + u8 i; + u8 byte_off = ALIGN_DOWN(msg->cmd_data_size, 4); + u8 *byte_buf = msg->cmd_data + byte_off; + + val = readl_relaxed(mbox->mbox_base + msg->mbox_offset + index * 0x4); + + for (i = 0u; i < extra_bits; i++) { + val &= ~(0xffu << (i * 8u)); + val |= (byte_buf[i] << (i * 8u)); + } + + writel_relaxed(val, mbox->mbox_base + msg->mbox_offset + index * 0x4); + } + } + + opt_sel = ((msg->mbox_offset << 7u) | (msg->cmd_opcode & 0x7fu)); + + tx_trigger = (opt_sel << SCB_CTRL_POS) & SCB_CTRL_MASK; + tx_trigger |= SCB_CTRL_REQ_MASK | SCB_STATUS_NOTIFY_MASK; + + if (mbox->control_scb) + regmap_write(mbox->control_scb, SERVICES_CR_OFFSET, tx_trigger); + else + writel_relaxed(tx_trigger, mbox->ctrl_base + SERVICES_CR_OFFSET); + + + return 0; +} + +static void mpfs_mbox_rx_data(struct mbox_chan *chan) +{ + struct mpfs_mbox *mbox = (struct mpfs_mbox *)chan->con_priv; + struct mpfs_mss_response *response = mbox->response; + u16 num_words = ALIGN((response->resp_size), (4)) / 4U; + u32 i; + + if (!response->resp_msg) { + dev_err(mbox->dev, "failed to assign memory for response %d\n", -ENOMEM); + return; + } + + /* + * We should *never* get an interrupt while the controller is + * still in the busy state. If we do, something has gone badly + * wrong & the content of the mailbox would not be valid. + */ + if (mpfs_mbox_busy(mbox)) { + dev_err(mbox->dev, "got an interrupt but system controller is busy\n"); + response->resp_status = 0xDEAD; + return; + } + + for (i = 0; i < num_words; i++) { + response->resp_msg[i] = + readl_relaxed(mbox->mbox_base + + mbox->resp_offset + i * 0x4); + } + + mbox_chan_received_data(chan, response); +} + +static irqreturn_t mpfs_mbox_inbox_isr(int irq, void *data) +{ + struct mbox_chan *chan = data; + struct mpfs_mbox *mbox = (struct mpfs_mbox *)chan->con_priv; + + if (mbox->sysreg_scb) + regmap_write(mbox->sysreg_scb, MESSAGE_INT_OFFSET, 0); + else + writel_relaxed(0, mbox->int_reg); + + mpfs_mbox_rx_data(chan); + + return IRQ_HANDLED; +} + +static int mpfs_mbox_startup(struct mbox_chan *chan) +{ + struct mpfs_mbox *mbox = (struct mpfs_mbox *)chan->con_priv; + int ret = 0; + + if (!mbox) + return -EINVAL; + + ret = devm_request_irq(mbox->dev, mbox->irq, mpfs_mbox_inbox_isr, 0, "mpfs-mailbox", chan); + if (ret) + dev_err(mbox->dev, "failed to register mailbox interrupt:%d\n", ret); + + return ret; +} + +static void mpfs_mbox_shutdown(struct mbox_chan *chan) +{ + struct mpfs_mbox *mbox = (struct mpfs_mbox *)chan->con_priv; + + devm_free_irq(mbox->dev, mbox->irq, chan); +} + +static const struct mbox_chan_ops mpfs_mbox_ops = { + .send_data = mpfs_mbox_send_data, + .startup = mpfs_mbox_startup, + .shutdown = mpfs_mbox_shutdown, + .last_tx_done = mpfs_mbox_last_tx_done, +}; + +static inline int mpfs_mbox_syscon_probe(struct mpfs_mbox *mbox, struct platform_device *pdev) +{ + mbox->control_scb = syscon_regmap_lookup_by_compatible("microchip,mpfs-control-scb"); + if (IS_ERR(mbox->control_scb)) + return PTR_ERR(mbox->control_scb); + + mbox->sysreg_scb = syscon_regmap_lookup_by_compatible("microchip,mpfs-sysreg-scb"); + if (IS_ERR(mbox->sysreg_scb)) + return PTR_ERR(mbox->sysreg_scb); + + mbox->mbox_base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(mbox->mbox_base)) + return PTR_ERR(mbox->mbox_base); + + return 0; +} + +static inline int mpfs_mbox_old_format_probe(struct mpfs_mbox *mbox, struct platform_device *pdev) +{ + dev_warn(&pdev->dev, "falling back to old devicetree format"); + + mbox->ctrl_base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(mbox->ctrl_base)) + return PTR_ERR(mbox->ctrl_base); + + mbox->int_reg = devm_platform_ioremap_resource(pdev, 1); + if (IS_ERR(mbox->int_reg)) + return PTR_ERR(mbox->int_reg); + + mbox->mbox_base = devm_platform_ioremap_resource(pdev, 2); + if (IS_ERR(mbox->mbox_base)) // account for the old dt-binding w/ 2 regs + mbox->mbox_base = mbox->ctrl_base + MAILBOX_REG_OFFSET; + + return 0; +} + +static int mpfs_mbox_probe(struct platform_device *pdev) +{ + struct mpfs_mbox *mbox; + int ret; + + mbox = devm_kzalloc(&pdev->dev, sizeof(*mbox), GFP_KERNEL); + if (!mbox) + return -ENOMEM; + + ret = mpfs_mbox_syscon_probe(mbox, pdev); + if (ret) { + /* + * set this to null, so it can be used as the decision for to + * regmap or not to regmap + */ + mbox->control_scb = NULL; + ret = mpfs_mbox_old_format_probe(mbox, pdev); + if (ret) + return ret; + } + mbox->irq = platform_get_irq(pdev, 0); + if (mbox->irq < 0) + return mbox->irq; + + mbox->dev = &pdev->dev; + + mbox->chans[0].con_priv = mbox; + mbox->controller.dev = mbox->dev; + mbox->controller.num_chans = 1; + mbox->controller.chans = mbox->chans; + mbox->controller.ops = &mpfs_mbox_ops; + mbox->controller.txdone_poll = true; + mbox->controller.txpoll_period = 10u; + + ret = devm_mbox_controller_register(&pdev->dev, &mbox->controller); + if (ret) { + dev_err(&pdev->dev, "Registering MPFS mailbox controller failed\n"); + return ret; + } + dev_info(&pdev->dev, "Registered MPFS mailbox controller driver\n"); + + return 0; +} + +static const struct of_device_id mpfs_mbox_of_match[] = { + {.compatible = "microchip,mpfs-mailbox", }, + {}, +}; +MODULE_DEVICE_TABLE(of, mpfs_mbox_of_match); + +static struct platform_driver mpfs_mbox_driver = { + .driver = { + .name = "mpfs-mailbox", + .of_match_table = mpfs_mbox_of_match, + }, + .probe = mpfs_mbox_probe, +}; +module_platform_driver(mpfs_mbox_driver); + +MODULE_LICENSE("GPL v2"); +MODULE_AUTHOR("Conor Dooley <conor.dooley@microchip.com>"); +MODULE_DESCRIPTION("MPFS mailbox controller driver"); |
