From 4352b8aee98005853aa63f57d6377282de17a33f Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sun, 23 Aug 2026 13:28:57 -0700 Subject: Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux 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 ... --- drivers/rtc/rtc-mxc_v2.c | 390 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 390 insertions(+) create mode 100644 drivers/rtc/rtc-mxc_v2.c (limited to 'drivers/rtc/rtc-mxc_v2.c') diff --git a/drivers/rtc/rtc-mxc_v2.c b/drivers/rtc/rtc-mxc_v2.c new file mode 100644 index 000000000..a07acbbcf --- /dev/null +++ b/drivers/rtc/rtc-mxc_v2.c @@ -0,0 +1,390 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Real Time Clock (RTC) Driver for i.MX53 + * Copyright (c) 2004-2011 Freescale Semiconductor, Inc. + * Copyright (c) 2017 Beckhoff Automation GmbH & Co. KG + */ + +#include +#include +#include +#include +#include +#include + +#define SRTC_LPPDR_INIT 0x41736166 /* init for glitch detect */ + +#define SRTC_LPCR_EN_LP BIT(3) /* lp enable */ +#define SRTC_LPCR_WAE BIT(4) /* lp wakeup alarm enable */ +#define SRTC_LPCR_ALP BIT(7) /* lp alarm flag */ +#define SRTC_LPCR_NSA BIT(11) /* lp non secure access */ +#define SRTC_LPCR_NVE BIT(14) /* lp non valid state exit bit */ +#define SRTC_LPCR_IE BIT(15) /* lp init state exit bit */ + +#define SRTC_LPSR_ALP BIT(3) /* lp alarm flag */ +#define SRTC_LPSR_NVES BIT(14) /* lp non-valid state exit status */ +#define SRTC_LPSR_IES BIT(15) /* lp init state exit status */ + +#define SRTC_LPSCMR 0x00 /* LP Secure Counter MSB Reg */ +#define SRTC_LPSCLR 0x04 /* LP Secure Counter LSB Reg */ +#define SRTC_LPSAR 0x08 /* LP Secure Alarm Reg */ +#define SRTC_LPCR 0x10 /* LP Control Reg */ +#define SRTC_LPSR 0x14 /* LP Status Reg */ +#define SRTC_LPPDR 0x18 /* LP Power Supply Glitch Detector Reg */ + +/* max. number of retries to read registers, 120 was max during test */ +#define REG_READ_TIMEOUT 2000 + +struct mxc_rtc_data { + struct rtc_device *rtc; + void __iomem *ioaddr; + struct clk *clk; + spinlock_t lock; /* protects register access */ + int irq; +}; + +/* + * This function does write synchronization for writes to the lp srtc block. + * To take care of the asynchronous CKIL clock, all writes from the IP domain + * will be synchronized to the CKIL domain. + * The caller should hold the pdata->lock + */ +static void mxc_rtc_sync_lp_locked(struct device *dev, void __iomem *ioaddr) +{ + unsigned int i; + + /* Wait for 3 CKIL cycles */ + for (i = 0; i < 3; i++) { + const u32 count = readl(ioaddr + SRTC_LPSCLR); + unsigned int timeout = REG_READ_TIMEOUT; + + while ((readl(ioaddr + SRTC_LPSCLR)) == count) { + if (!--timeout) { + dev_err_once(dev, "SRTC_LPSCLR stuck! Check your hw.\n"); + return; + } + } + } +} + +/* This function is the RTC interrupt service routine. */ +static irqreturn_t mxc_rtc_interrupt(int irq, void *dev_id) +{ + struct device *dev = dev_id; + struct mxc_rtc_data *pdata = dev_get_drvdata(dev); + void __iomem *ioaddr = pdata->ioaddr; + u32 lp_status; + u32 lp_cr; + + spin_lock(&pdata->lock); + if (clk_enable(pdata->clk)) { + spin_unlock(&pdata->lock); + return IRQ_NONE; + } + + lp_status = readl(ioaddr + SRTC_LPSR); + lp_cr = readl(ioaddr + SRTC_LPCR); + + /* update irq data & counter */ + if (lp_status & SRTC_LPSR_ALP) { + if (lp_cr & SRTC_LPCR_ALP) + rtc_update_irq(pdata->rtc, 1, RTC_AF | RTC_IRQF); + + /* disable further lp alarm interrupts */ + lp_cr &= ~(SRTC_LPCR_ALP | SRTC_LPCR_WAE); + } + + /* Update interrupt enables */ + writel(lp_cr, ioaddr + SRTC_LPCR); + + /* clear interrupt status */ + writel(lp_status, ioaddr + SRTC_LPSR); + + mxc_rtc_sync_lp_locked(dev, ioaddr); + clk_disable(pdata->clk); + spin_unlock(&pdata->lock); + return IRQ_HANDLED; +} + +/* + * Enable clk and aquire spinlock + * @return 0 if successful; non-zero otherwise. + */ +static int mxc_rtc_lock(struct mxc_rtc_data *const pdata) +{ + int ret; + + spin_lock_irq(&pdata->lock); + ret = clk_enable(pdata->clk); + if (ret) { + spin_unlock_irq(&pdata->lock); + return ret; + } + return 0; +} + +static int mxc_rtc_unlock(struct mxc_rtc_data *const pdata) +{ + clk_disable(pdata->clk); + spin_unlock_irq(&pdata->lock); + return 0; +} + +/* + * This function reads the current RTC time into tm in Gregorian date. + * + * @param tm contains the RTC time value upon return + * + * @return 0 if successful; non-zero otherwise. + */ +static int mxc_rtc_read_time(struct device *dev, struct rtc_time *tm) +{ + struct mxc_rtc_data *pdata = dev_get_drvdata(dev); + const int clk_failed = clk_enable(pdata->clk); + + if (!clk_failed) { + const time64_t now = readl(pdata->ioaddr + SRTC_LPSCMR); + + rtc_time64_to_tm(now, tm); + clk_disable(pdata->clk); + return 0; + } + return clk_failed; +} + +/* + * This function sets the internal RTC time based on tm in Gregorian date. + * + * @param tm the time value to be set in the RTC + * + * @return 0 if successful; non-zero otherwise. + */ +static int mxc_rtc_set_time(struct device *dev, struct rtc_time *tm) +{ + struct mxc_rtc_data *pdata = dev_get_drvdata(dev); + time64_t time = rtc_tm_to_time64(tm); + int ret; + + ret = mxc_rtc_lock(pdata); + if (ret) + return ret; + + writel(time, pdata->ioaddr + SRTC_LPSCMR); + mxc_rtc_sync_lp_locked(dev, pdata->ioaddr); + return mxc_rtc_unlock(pdata); +} + +/* + * This function reads the current alarm value into the passed in \b alrm + * argument. It updates the \b alrm's pending field value based on the whether + * an alarm interrupt occurs or not. + * + * @param alrm contains the RTC alarm value upon return + * + * @return 0 if successful; non-zero otherwise. + */ +static int mxc_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm) +{ + struct mxc_rtc_data *pdata = dev_get_drvdata(dev); + void __iomem *ioaddr = pdata->ioaddr; + int ret; + + ret = mxc_rtc_lock(pdata); + if (ret) + return ret; + + rtc_time64_to_tm(readl(ioaddr + SRTC_LPSAR), &alrm->time); + alrm->pending = !!(readl(ioaddr + SRTC_LPSR) & SRTC_LPSR_ALP); + return mxc_rtc_unlock(pdata); +} + +/* + * Enable/Disable alarm interrupt + * The caller should hold the pdata->lock + */ +static void mxc_rtc_alarm_irq_enable_locked(struct mxc_rtc_data *pdata, + unsigned int enable) +{ + u32 lp_cr = readl(pdata->ioaddr + SRTC_LPCR); + + if (enable) + lp_cr |= (SRTC_LPCR_ALP | SRTC_LPCR_WAE); + else + lp_cr &= ~(SRTC_LPCR_ALP | SRTC_LPCR_WAE); + + writel(lp_cr, pdata->ioaddr + SRTC_LPCR); +} + +static int mxc_rtc_alarm_irq_enable(struct device *dev, unsigned int enable) +{ + struct mxc_rtc_data *pdata = dev_get_drvdata(dev); + int ret = mxc_rtc_lock(pdata); + + if (ret) + return ret; + + mxc_rtc_alarm_irq_enable_locked(pdata, enable); + return mxc_rtc_unlock(pdata); +} + +/* + * This function sets the RTC alarm based on passed in alrm. + * + * @param alrm the alarm value to be set in the RTC + * + * @return 0 if successful; non-zero otherwise. + */ +static int mxc_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm) +{ + const time64_t time = rtc_tm_to_time64(&alrm->time); + struct mxc_rtc_data *pdata = dev_get_drvdata(dev); + int ret = mxc_rtc_lock(pdata); + + if (ret) + return ret; + + writel((u32)time, pdata->ioaddr + SRTC_LPSAR); + + /* clear alarm interrupt status bit */ + writel(SRTC_LPSR_ALP, pdata->ioaddr + SRTC_LPSR); + mxc_rtc_sync_lp_locked(dev, pdata->ioaddr); + + mxc_rtc_alarm_irq_enable_locked(pdata, alrm->enabled); + mxc_rtc_sync_lp_locked(dev, pdata->ioaddr); + mxc_rtc_unlock(pdata); + return ret; +} + +static const struct rtc_class_ops mxc_rtc_ops = { + .read_time = mxc_rtc_read_time, + .set_time = mxc_rtc_set_time, + .read_alarm = mxc_rtc_read_alarm, + .set_alarm = mxc_rtc_set_alarm, + .alarm_irq_enable = mxc_rtc_alarm_irq_enable, +}; + +static int mxc_rtc_wait_for_flag(void __iomem *ioaddr, int flag) +{ + unsigned int timeout = REG_READ_TIMEOUT; + + while (!(readl(ioaddr) & flag)) { + if (!--timeout) + return -EBUSY; + } + return 0; +} + +static int mxc_rtc_probe(struct platform_device *pdev) +{ + struct mxc_rtc_data *pdata; + void __iomem *ioaddr; + int ret = 0; + + pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL); + if (!pdata) + return -ENOMEM; + + pdata->ioaddr = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(pdata->ioaddr)) + return PTR_ERR(pdata->ioaddr); + + ioaddr = pdata->ioaddr; + + pdata->clk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(pdata->clk)) { + dev_err(&pdev->dev, "unable to get rtc clock!\n"); + return PTR_ERR(pdata->clk); + } + + spin_lock_init(&pdata->lock); + pdata->irq = platform_get_irq(pdev, 0); + if (pdata->irq < 0) + return pdata->irq; + + device_init_wakeup(&pdev->dev, true); + ret = dev_pm_set_wake_irq(&pdev->dev, pdata->irq); + if (ret) + dev_err(&pdev->dev, "failed to enable irq wake\n"); + + ret = clk_prepare_enable(pdata->clk); + if (ret) + return ret; + /* initialize glitch detect */ + writel(SRTC_LPPDR_INIT, ioaddr + SRTC_LPPDR); + + /* clear lp interrupt status */ + writel(0xFFFFFFFF, ioaddr + SRTC_LPSR); + + /* move out of init state */ + writel((SRTC_LPCR_IE | SRTC_LPCR_NSA), ioaddr + SRTC_LPCR); + ret = mxc_rtc_wait_for_flag(ioaddr + SRTC_LPSR, SRTC_LPSR_IES); + if (ret) { + dev_err(&pdev->dev, "Timeout waiting for SRTC_LPSR_IES\n"); + clk_disable_unprepare(pdata->clk); + return ret; + } + + /* move out of non-valid state */ + writel((SRTC_LPCR_IE | SRTC_LPCR_NVE | SRTC_LPCR_NSA | + SRTC_LPCR_EN_LP), ioaddr + SRTC_LPCR); + ret = mxc_rtc_wait_for_flag(ioaddr + SRTC_LPSR, SRTC_LPSR_NVES); + if (ret) { + dev_err(&pdev->dev, "Timeout waiting for SRTC_LPSR_NVES\n"); + clk_disable_unprepare(pdata->clk); + return ret; + } + + pdata->rtc = devm_rtc_allocate_device(&pdev->dev); + if (IS_ERR(pdata->rtc)) { + clk_disable_unprepare(pdata->clk); + return PTR_ERR(pdata->rtc); + } + + pdata->rtc->ops = &mxc_rtc_ops; + pdata->rtc->range_max = U32_MAX; + + clk_disable(pdata->clk); + platform_set_drvdata(pdev, pdata); + ret = + devm_request_irq(&pdev->dev, pdata->irq, mxc_rtc_interrupt, 0, + pdev->name, &pdev->dev); + if (ret < 0) { + dev_err(&pdev->dev, "interrupt not available.\n"); + clk_unprepare(pdata->clk); + return ret; + } + + ret = devm_rtc_register_device(pdata->rtc); + if (ret < 0) + clk_unprepare(pdata->clk); + + return ret; +} + +static void mxc_rtc_remove(struct platform_device *pdev) +{ + struct mxc_rtc_data *pdata = platform_get_drvdata(pdev); + + clk_disable_unprepare(pdata->clk); +} + +static const struct of_device_id mxc_ids[] = { + { .compatible = "fsl,imx53-rtc", }, + {} +}; +MODULE_DEVICE_TABLE(of, mxc_ids); + +static struct platform_driver mxc_rtc_driver = { + .driver = { + .name = "mxc_rtc_v2", + .of_match_table = mxc_ids, + }, + .probe = mxc_rtc_probe, + .remove = mxc_rtc_remove, +}; + +module_platform_driver(mxc_rtc_driver); + +MODULE_AUTHOR("Freescale Semiconductor, Inc."); +MODULE_DESCRIPTION("Real Time Clock (RTC) Driver for i.MX53"); +MODULE_LICENSE("GPL"); -- cgit v1.3.1