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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
commit4352b8aee98005853aa63f57d6377282de17a33f (patch)
tree27614d7a9ef05c32d089004e104364ce42324837 /drivers/rtc/rtc-ti-k3.c
downloadlinux-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/rtc/rtc-ti-k3.c')
-rw-r--r--drivers/rtc/rtc-ti-k3.c670
1 files changed, 670 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-ti-k3.c b/drivers/rtc/rtc-ti-k3.c
new file mode 100644
index 000000000..8df00319c
--- /dev/null
+++ b/drivers/rtc/rtc-ti-k3.c
@@ -0,0 +1,670 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Texas Instruments K3 RTC driver
+ *
+ * Copyright (C) 2021-2022 Texas Instruments Incorporated - https://www.ti.com/
+ */
+
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/sys_soc.h>
+#include <linux/property.h>
+#include <linux/regmap.h>
+#include <linux/rtc.h>
+
+/* Registers */
+#define REG_K3RTC_S_CNT_LSW 0x08
+#define REG_K3RTC_S_CNT_MSW 0x0c
+#define REG_K3RTC_COMP 0x10
+#define REG_K3RTC_ON_OFF_S_CNT_LSW 0x20
+#define REG_K3RTC_ON_OFF_S_CNT_MSW 0x24
+#define REG_K3RTC_SCRATCH0 0x30
+#define REG_K3RTC_SCRATCH7 0x4c
+#define REG_K3RTC_GENERAL_CTL 0x50
+#define REG_K3RTC_IRQSTATUS_RAW_SYS 0x54
+#define REG_K3RTC_IRQSTATUS_SYS 0x58
+#define REG_K3RTC_IRQENABLE_SET_SYS 0x5c
+#define REG_K3RTC_IRQENABLE_CLR_SYS 0x60
+#define REG_K3RTC_SYNCPEND 0x68
+#define REG_K3RTC_KICK0 0x70
+#define REG_K3RTC_KICK1 0x74
+
+/* Freeze when lsw is read and unfreeze when msw is read */
+#define K3RTC_CNT_FMODE_S_CNT_VALUE (0x2 << 24)
+
+/* Magic values for lock/unlock */
+#define K3RTC_KICK0_UNLOCK_VALUE 0x83e70b13
+#define K3RTC_KICK1_UNLOCK_VALUE 0x95a4f1e0
+
+/* Multiplier for ppb conversions */
+#define K3RTC_PPB_MULT (1000000000LL)
+/* Min and max values supported with 'offset' interface (swapped sign) */
+#define K3RTC_MIN_OFFSET (-277761)
+#define K3RTC_MAX_OFFSET (277778)
+
+static const struct regmap_config ti_k3_rtc_regmap_config = {
+ .name = "peripheral-registers",
+ .reg_bits = 32,
+ .val_bits = 32,
+ .reg_stride = 4,
+ .max_register = REG_K3RTC_KICK1,
+};
+
+enum ti_k3_rtc_fields {
+ K3RTC_KICK0,
+ K3RTC_KICK1,
+ K3RTC_S_CNT_LSW,
+ K3RTC_S_CNT_MSW,
+ K3RTC_O32K_OSC_DEP_EN,
+ K3RTC_UNLOCK,
+ K3RTC_CNT_FMODE,
+ K3RTC_PEND,
+ K3RTC_RELOAD_FROM_BBD,
+ K3RTC_COMP,
+
+ K3RTC_ALM_S_CNT_LSW,
+ K3RTC_ALM_S_CNT_MSW,
+ K3RTC_IRQ_STATUS_RAW,
+ K3RTC_IRQ_STATUS,
+ K3RTC_IRQ_ENABLE_SET,
+ K3RTC_IRQ_ENABLE_CLR,
+
+ K3RTC_IRQ_STATUS_ALT,
+ K3RTC_IRQ_ENABLE_CLR_ALT,
+
+ K3_RTC_MAX_FIELDS
+};
+
+static const struct reg_field ti_rtc_reg_fields[] = {
+ [K3RTC_KICK0] = REG_FIELD(REG_K3RTC_KICK0, 0, 31),
+ [K3RTC_KICK1] = REG_FIELD(REG_K3RTC_KICK1, 0, 31),
+ [K3RTC_S_CNT_LSW] = REG_FIELD(REG_K3RTC_S_CNT_LSW, 0, 31),
+ [K3RTC_S_CNT_MSW] = REG_FIELD(REG_K3RTC_S_CNT_MSW, 0, 15),
+ [K3RTC_O32K_OSC_DEP_EN] = REG_FIELD(REG_K3RTC_GENERAL_CTL, 21, 21),
+ [K3RTC_UNLOCK] = REG_FIELD(REG_K3RTC_GENERAL_CTL, 23, 23),
+ [K3RTC_CNT_FMODE] = REG_FIELD(REG_K3RTC_GENERAL_CTL, 24, 25),
+ [K3RTC_PEND] = REG_FIELD(REG_K3RTC_SYNCPEND, 0, 1),
+ [K3RTC_RELOAD_FROM_BBD] = REG_FIELD(REG_K3RTC_SYNCPEND, 31, 31),
+ [K3RTC_COMP] = REG_FIELD(REG_K3RTC_COMP, 0, 31),
+
+ /* We use on to off as alarm trigger */
+ [K3RTC_ALM_S_CNT_LSW] = REG_FIELD(REG_K3RTC_ON_OFF_S_CNT_LSW, 0, 31),
+ [K3RTC_ALM_S_CNT_MSW] = REG_FIELD(REG_K3RTC_ON_OFF_S_CNT_MSW, 0, 15),
+ [K3RTC_IRQ_STATUS_RAW] = REG_FIELD(REG_K3RTC_IRQSTATUS_RAW_SYS, 0, 0),
+ [K3RTC_IRQ_STATUS] = REG_FIELD(REG_K3RTC_IRQSTATUS_SYS, 0, 0),
+ [K3RTC_IRQ_ENABLE_SET] = REG_FIELD(REG_K3RTC_IRQENABLE_SET_SYS, 0, 0),
+ [K3RTC_IRQ_ENABLE_CLR] = REG_FIELD(REG_K3RTC_IRQENABLE_CLR_SYS, 0, 0),
+ /* Off to on is alternate */
+ [K3RTC_IRQ_STATUS_ALT] = REG_FIELD(REG_K3RTC_IRQSTATUS_SYS, 1, 1),
+ [K3RTC_IRQ_ENABLE_CLR_ALT] = REG_FIELD(REG_K3RTC_IRQENABLE_CLR_SYS, 1, 1),
+};
+
+/**
+ * struct ti_k3_rtc - Private data for ti-k3-rtc
+ * @irq: IRQ
+ * @sync_timeout_us: data sync timeout period in uSec
+ * @rate_32k: 32k clock rate in Hz
+ * @rtc_dev: rtc device
+ * @regmap: rtc mmio regmap
+ * @r_fields: rtc register fields
+ */
+struct ti_k3_rtc {
+ unsigned int irq;
+ u32 sync_timeout_us;
+ unsigned long rate_32k;
+ struct rtc_device *rtc_dev;
+ struct regmap *regmap;
+ struct regmap_field *r_fields[K3_RTC_MAX_FIELDS];
+};
+
+static int k3rtc_field_read(struct ti_k3_rtc *priv, enum ti_k3_rtc_fields f)
+{
+ int ret;
+ int val;
+
+ ret = regmap_field_read(priv->r_fields[f], &val);
+ /*
+ * We shouldn't be seeing regmap fail on us for mmio reads
+ * This is possible if clock context fails, but that isn't the case for us
+ */
+ if (WARN_ON_ONCE(ret))
+ return ret;
+ return val;
+}
+
+static void k3rtc_field_write(struct ti_k3_rtc *priv, enum ti_k3_rtc_fields f, u32 val)
+{
+ regmap_field_write(priv->r_fields[f], val);
+}
+
+/**
+ * k3rtc_fence - Ensure a register sync took place between the two domains
+ * @priv: pointer to priv data
+ *
+ * Return: 0 if the sync took place, else returns -ETIMEDOUT
+ */
+static int k3rtc_fence(struct ti_k3_rtc *priv)
+{
+ int ret;
+
+ ret = regmap_field_read_poll_timeout(priv->r_fields[K3RTC_PEND], ret,
+ !ret, 2, priv->sync_timeout_us);
+
+ return ret;
+}
+
+static inline int k3rtc_check_unlocked(struct ti_k3_rtc *priv)
+{
+ int ret;
+
+ ret = k3rtc_field_read(priv, K3RTC_UNLOCK);
+ if (ret < 0)
+ return ret;
+
+ return (ret) ? 0 : 1;
+}
+
+static int k3rtc_unlock_rtc(struct ti_k3_rtc *priv)
+{
+ int ret;
+
+ ret = k3rtc_check_unlocked(priv);
+ if (!ret)
+ return ret;
+
+ k3rtc_field_write(priv, K3RTC_KICK0, K3RTC_KICK0_UNLOCK_VALUE);
+ k3rtc_field_write(priv, K3RTC_KICK1, K3RTC_KICK1_UNLOCK_VALUE);
+
+ /* Skip fence since we are going to check the unlock bit as fence */
+ ret = regmap_field_read_poll_timeout(priv->r_fields[K3RTC_UNLOCK], ret,
+ ret, 2, priv->sync_timeout_us);
+
+ return ret;
+}
+
+/*
+ * This is the list of SoCs affected by TI's i2327 errata causing the RTC
+ * state-machine to break if not unlocked fast enough during boot. These
+ * SoCs must have the bootloader unlock this device very early in the
+ * boot-flow before we (Linux) can use this device.
+ */
+static const struct soc_device_attribute has_erratum_i2327[] = {
+ { .family = "AM62X", .revision = "SR1.0" },
+ { /* sentinel */ }
+};
+
+static int k3rtc_configure(struct device *dev)
+{
+ int ret;
+ struct ti_k3_rtc *priv = dev_get_drvdata(dev);
+
+ /*
+ * HWBUG: The compare state machine is broken if the RTC module
+ * is NOT unlocked in under one second of boot - which is pretty long
+ * time from the perspective of Linux driver (module load, u-boot
+ * shell all can take much longer than this.
+ *
+ * In such occurrence, it is assumed that the RTC module is unusable
+ */
+ if (soc_device_match(has_erratum_i2327)) {
+ ret = k3rtc_check_unlocked(priv);
+ /* If there is an error OR if we are locked, return error */
+ if (ret) {
+ dev_err(dev,
+ HW_ERR "Erratum i2327 unlock QUIRK! Cannot operate!!\n");
+ return -EFAULT;
+ }
+ } else {
+ /* May need to explicitly unlock first time */
+ ret = k3rtc_unlock_rtc(priv);
+ if (ret) {
+ dev_err(dev, "Failed to unlock(%d)!\n", ret);
+ return ret;
+ }
+ }
+
+ /* Enable Shadow register sync on 32k clock boundary */
+ k3rtc_field_write(priv, K3RTC_O32K_OSC_DEP_EN, 0x1);
+
+ /*
+ * Wait at least clock sync time before proceeding further programming.
+ * This ensures that the 32k based sync is active.
+ */
+ usleep_range(priv->sync_timeout_us, priv->sync_timeout_us + 5);
+
+ /* We need to ensure fence here to make sure sync here */
+ ret = k3rtc_fence(priv);
+ if (ret) {
+ dev_err(dev,
+ "Failed fence osc_dep enable(%d) - is 32k clk working?!\n", ret);
+ return ret;
+ }
+
+ /*
+ * FMODE setting: Reading lower seconds will freeze value on higher
+ * seconds. This also implies that we must *ALWAYS* read lower seconds
+ * prior to reading higher seconds
+ */
+ k3rtc_field_write(priv, K3RTC_CNT_FMODE, K3RTC_CNT_FMODE_S_CNT_VALUE);
+
+ /* Clear any spurious IRQ sources if any */
+ k3rtc_field_write(priv, K3RTC_IRQ_STATUS_ALT, 0x1);
+ k3rtc_field_write(priv, K3RTC_IRQ_STATUS, 0x1);
+ /* Disable all IRQs */
+ k3rtc_field_write(priv, K3RTC_IRQ_ENABLE_CLR_ALT, 0x1);
+ k3rtc_field_write(priv, K3RTC_IRQ_ENABLE_CLR, 0x1);
+
+ /* And.. Let us Sync the writes in */
+ return k3rtc_fence(priv);
+}
+
+static int ti_k3_rtc_read_time(struct device *dev, struct rtc_time *tm)
+{
+ struct ti_k3_rtc *priv = dev_get_drvdata(dev);
+ u32 seconds_lo, seconds_hi;
+
+ seconds_lo = k3rtc_field_read(priv, K3RTC_S_CNT_LSW);
+ seconds_hi = k3rtc_field_read(priv, K3RTC_S_CNT_MSW);
+
+ rtc_time64_to_tm((((time64_t)seconds_hi) << 32) | (time64_t)seconds_lo, tm);
+
+ return 0;
+}
+
+static int ti_k3_rtc_set_time(struct device *dev, struct rtc_time *tm)
+{
+ struct ti_k3_rtc *priv = dev_get_drvdata(dev);
+ time64_t seconds;
+
+ seconds = rtc_tm_to_time64(tm);
+
+ /*
+ * Read operation on LSW will freeze the RTC, so to update
+ * the time, we cannot use field operations. Just write since the
+ * reserved bits are ignored.
+ */
+ regmap_write(priv->regmap, REG_K3RTC_S_CNT_LSW, seconds);
+ regmap_write(priv->regmap, REG_K3RTC_S_CNT_MSW, seconds >> 32);
+
+ return k3rtc_fence(priv);
+}
+
+static int ti_k3_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
+{
+ struct ti_k3_rtc *priv = dev_get_drvdata(dev);
+ u32 reg;
+ u32 offset = enabled ? K3RTC_IRQ_ENABLE_SET : K3RTC_IRQ_ENABLE_CLR;
+
+ reg = k3rtc_field_read(priv, K3RTC_IRQ_ENABLE_SET);
+ if ((enabled && reg) || (!enabled && !reg))
+ return 0;
+
+ k3rtc_field_write(priv, offset, 0x1);
+
+ /*
+ * Ensure the write sync is through - NOTE: it should be OK to have
+ * ISR to fire as we are checking sync (which should be done in a 32k
+ * cycle or so).
+ */
+ return k3rtc_fence(priv);
+}
+
+static int ti_k3_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
+{
+ struct ti_k3_rtc *priv = dev_get_drvdata(dev);
+ u32 seconds_lo, seconds_hi;
+
+ seconds_lo = k3rtc_field_read(priv, K3RTC_ALM_S_CNT_LSW);
+ seconds_hi = k3rtc_field_read(priv, K3RTC_ALM_S_CNT_MSW);
+
+ rtc_time64_to_tm((((time64_t)seconds_hi) << 32) | (time64_t)seconds_lo, &alarm->time);
+
+ alarm->enabled = k3rtc_field_read(priv, K3RTC_IRQ_ENABLE_SET);
+
+ return 0;
+}
+
+static int ti_k3_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
+{
+ struct ti_k3_rtc *priv = dev_get_drvdata(dev);
+ time64_t seconds;
+ int ret;
+
+ seconds = rtc_tm_to_time64(&alarm->time);
+
+ k3rtc_field_write(priv, K3RTC_ALM_S_CNT_LSW, seconds);
+ k3rtc_field_write(priv, K3RTC_ALM_S_CNT_MSW, (seconds >> 32));
+
+ /* Make sure the alarm time is synced in */
+ ret = k3rtc_fence(priv);
+ if (ret) {
+ dev_err(dev, "Failed to fence(%d)! Potential config issue?\n", ret);
+ return ret;
+ }
+
+ /* Alarm IRQ enable will do a sync */
+ return ti_k3_rtc_alarm_irq_enable(dev, alarm->enabled);
+}
+
+static int ti_k3_rtc_read_offset(struct device *dev, long *offset)
+{
+ struct ti_k3_rtc *priv = dev_get_drvdata(dev);
+ u32 ticks_per_hr = priv->rate_32k * 3600;
+ int comp;
+ s64 tmp;
+
+ comp = k3rtc_field_read(priv, K3RTC_COMP);
+
+ /* Convert from RTC calibration register format to ppb format */
+ tmp = comp * (s64)K3RTC_PPB_MULT;
+ if (tmp < 0)
+ tmp -= ticks_per_hr / 2LL;
+ else
+ tmp += ticks_per_hr / 2LL;
+ tmp = div_s64(tmp, ticks_per_hr);
+
+ /* Offset value operates in negative way, so swap sign */
+ *offset = (long)-tmp;
+
+ return 0;
+}
+
+static int ti_k3_rtc_set_offset(struct device *dev, long offset)
+{
+ struct ti_k3_rtc *priv = dev_get_drvdata(dev);
+ u32 ticks_per_hr = priv->rate_32k * 3600;
+ int comp;
+ s64 tmp;
+
+ /* Make sure offset value is within supported range */
+ if (offset < K3RTC_MIN_OFFSET || offset > K3RTC_MAX_OFFSET)
+ return -ERANGE;
+
+ /* Convert from ppb format to RTC calibration register format */
+ tmp = offset * (s64)ticks_per_hr;
+ if (tmp < 0)
+ tmp -= K3RTC_PPB_MULT / 2LL;
+ else
+ tmp += K3RTC_PPB_MULT / 2LL;
+ tmp = div_s64(tmp, K3RTC_PPB_MULT);
+
+ /* Offset value operates in negative way, so swap sign */
+ comp = (int)-tmp;
+
+ k3rtc_field_write(priv, K3RTC_COMP, comp);
+
+ return k3rtc_fence(priv);
+}
+
+static irqreturn_t ti_k3_rtc_interrupt(s32 irq, void *dev_id)
+{
+ struct device *dev = dev_id;
+ struct ti_k3_rtc *priv = dev_get_drvdata(dev);
+ u32 reg;
+ int ret;
+
+ /*
+ * IRQ assertion can be very fast, however, the IRQ Status clear
+ * de-assert depends on 32k clock edge in the 32k domain
+ * If we clear the status prior to the first 32k clock edge,
+ * the status bit is cleared, but the IRQ stays re-asserted.
+ *
+ * To prevent this condition, we need to wait for clock sync time.
+ * We can either do that by polling the 32k observability signal for
+ * a toggle OR we could just sleep and let the processor do other
+ * stuff.
+ */
+ usleep_range(priv->sync_timeout_us, priv->sync_timeout_us + 2);
+
+ /* Lets make sure that this is a valid interrupt */
+ reg = k3rtc_field_read(priv, K3RTC_IRQ_STATUS);
+
+ if (!reg) {
+ u32 raw = k3rtc_field_read(priv, K3RTC_IRQ_STATUS_RAW);
+
+ dev_err(dev,
+ HW_ERR
+ "Erratum i2327/IRQ trig: status: 0x%08x / 0x%08x\n", reg, raw);
+ return IRQ_NONE;
+ }
+
+ /*
+ * Write 1 to clear status reg
+ * We cannot use a field operation here due to a potential race between
+ * 32k domain and vbus domain.
+ */
+ regmap_write(priv->regmap, REG_K3RTC_IRQSTATUS_SYS, 0x1);
+
+ /* Sync the write in */
+ ret = k3rtc_fence(priv);
+ if (ret) {
+ dev_err(dev, "Failed to fence irq status clr(%d)!\n", ret);
+ return IRQ_NONE;
+ }
+
+ /*
+ * Force the 32k status to be reloaded back in to ensure status is
+ * reflected back correctly.
+ */
+ k3rtc_field_write(priv, K3RTC_RELOAD_FROM_BBD, 0x1);
+
+ /* Ensure the write sync is through */
+ ret = k3rtc_fence(priv);
+ if (ret) {
+ dev_err(dev, "Failed to fence reload from bbd(%d)!\n", ret);
+ return IRQ_NONE;
+ }
+
+ /* Now we ensure that the status bit is cleared */
+ ret = regmap_field_read_poll_timeout(priv->r_fields[K3RTC_IRQ_STATUS],
+ ret, !ret, 2, priv->sync_timeout_us);
+ if (ret) {
+ dev_err(dev, "Time out waiting for status clear\n");
+ return IRQ_NONE;
+ }
+
+ /* Notify RTC core on event */
+ rtc_update_irq(priv->rtc_dev, 1, RTC_IRQF | RTC_AF);
+
+ return IRQ_HANDLED;
+}
+
+static const struct rtc_class_ops ti_k3_rtc_ops = {
+ .read_time = ti_k3_rtc_read_time,
+ .set_time = ti_k3_rtc_set_time,
+ .read_alarm = ti_k3_rtc_read_alarm,
+ .set_alarm = ti_k3_rtc_set_alarm,
+ .read_offset = ti_k3_rtc_read_offset,
+ .set_offset = ti_k3_rtc_set_offset,
+ .alarm_irq_enable = ti_k3_rtc_alarm_irq_enable,
+};
+
+static int ti_k3_rtc_scratch_read(void *priv_data, unsigned int offset,
+ void *val, size_t bytes)
+{
+ struct ti_k3_rtc *priv = (struct ti_k3_rtc *)priv_data;
+
+ return regmap_bulk_read(priv->regmap, REG_K3RTC_SCRATCH0 + offset, val, bytes / 4);
+}
+
+static int ti_k3_rtc_scratch_write(void *priv_data, unsigned int offset,
+ void *val, size_t bytes)
+{
+ struct ti_k3_rtc *priv = (struct ti_k3_rtc *)priv_data;
+ int ret;
+
+ ret = regmap_bulk_write(priv->regmap, REG_K3RTC_SCRATCH0 + offset, val, bytes / 4);
+ if (ret)
+ return ret;
+
+ return k3rtc_fence(priv);
+}
+
+static struct nvmem_config ti_k3_rtc_nvmem_config = {
+ .name = "ti_k3_rtc_scratch",
+ .word_size = 4,
+ .stride = 4,
+ .size = REG_K3RTC_SCRATCH7 - REG_K3RTC_SCRATCH0 + 4,
+ .reg_read = ti_k3_rtc_scratch_read,
+ .reg_write = ti_k3_rtc_scratch_write,
+};
+
+static int k3rtc_get_32kclk(struct device *dev, struct ti_k3_rtc *priv)
+{
+ struct clk *clk;
+
+ clk = devm_clk_get_enabled(dev, "osc32k");
+ if (IS_ERR(clk))
+ return PTR_ERR(clk);
+
+ priv->rate_32k = clk_get_rate(clk);
+
+ /* Make sure we are exact 32k clock. Else, try to compensate delay */
+ if (priv->rate_32k != 32768)
+ dev_warn(dev, "Clock rate %ld is not 32768! Could misbehave!\n",
+ priv->rate_32k);
+
+ /*
+ * Sync timeout should be two 32k clk sync cycles = ~61uS. We double
+ * it to comprehend intermediate bus segment and cpu frequency
+ * deltas
+ */
+ priv->sync_timeout_us = (u32)(DIV_ROUND_UP_ULL(1000000, priv->rate_32k) * 4);
+
+ return 0;
+}
+
+static int k3rtc_get_vbusclk(struct device *dev, struct ti_k3_rtc *priv)
+{
+ struct clk *clk;
+
+ /* Note: VBUS isn't a context clock, it is needed for hardware operation */
+ clk = devm_clk_get_enabled(dev, "vbus");
+ if (IS_ERR(clk))
+ return PTR_ERR(clk);
+
+ return 0;
+}
+
+static int ti_k3_rtc_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct ti_k3_rtc *priv;
+ void __iomem *rtc_base;
+ int ret;
+
+ priv = devm_kzalloc(dev, sizeof(struct ti_k3_rtc), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ rtc_base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(rtc_base))
+ return PTR_ERR(rtc_base);
+
+ priv->regmap = devm_regmap_init_mmio(dev, rtc_base, &ti_k3_rtc_regmap_config);
+ if (IS_ERR(priv->regmap))
+ return PTR_ERR(priv->regmap);
+
+ ret = devm_regmap_field_bulk_alloc(dev, priv->regmap, priv->r_fields,
+ ti_rtc_reg_fields, K3_RTC_MAX_FIELDS);
+ if (ret)
+ return ret;
+
+ ret = k3rtc_get_32kclk(dev, priv);
+ if (ret)
+ return ret;
+ ret = k3rtc_get_vbusclk(dev, priv);
+ if (ret)
+ return ret;
+
+ ret = platform_get_irq(pdev, 0);
+ if (ret < 0)
+ return ret;
+ priv->irq = (unsigned int)ret;
+
+ priv->rtc_dev = devm_rtc_allocate_device(dev);
+ if (IS_ERR(priv->rtc_dev))
+ return PTR_ERR(priv->rtc_dev);
+
+ priv->rtc_dev->ops = &ti_k3_rtc_ops;
+ priv->rtc_dev->range_max = (1ULL << 48) - 1; /* 48Bit seconds */
+ ti_k3_rtc_nvmem_config.priv = priv;
+
+ ret = devm_request_threaded_irq(dev, priv->irq, NULL,
+ ti_k3_rtc_interrupt,
+ IRQF_TRIGGER_HIGH | IRQF_ONESHOT,
+ dev_name(dev), dev);
+ if (ret) {
+ dev_err(dev, "Could not request IRQ: %d\n", ret);
+ return ret;
+ }
+
+ platform_set_drvdata(pdev, priv);
+
+ ret = k3rtc_configure(dev);
+ if (ret)
+ return ret;
+
+ if (device_property_present(dev, "wakeup-source"))
+ device_init_wakeup(dev, true);
+ else
+ device_set_wakeup_capable(dev, true);
+
+ ret = devm_rtc_register_device(priv->rtc_dev);
+ if (ret)
+ return ret;
+
+ return devm_rtc_nvmem_register(priv->rtc_dev, &ti_k3_rtc_nvmem_config);
+}
+
+static const struct of_device_id ti_k3_rtc_of_match_table[] = {
+ {.compatible = "ti,am62-rtc" },
+ {}
+};
+MODULE_DEVICE_TABLE(of, ti_k3_rtc_of_match_table);
+
+static int __maybe_unused ti_k3_rtc_suspend(struct device *dev)
+{
+ struct ti_k3_rtc *priv = dev_get_drvdata(dev);
+
+ if (device_may_wakeup(dev))
+ return enable_irq_wake(priv->irq);
+
+ return 0;
+}
+
+static int __maybe_unused ti_k3_rtc_resume(struct device *dev)
+{
+ struct ti_k3_rtc *priv = dev_get_drvdata(dev);
+ int ret = 0;
+
+ if (k3rtc_check_unlocked(priv)) {
+ /* RTC locked implies low power mode exit where RTC loses context */
+ ret = k3rtc_configure(dev);
+ if (ret)
+ return ret;
+ }
+
+ if (device_may_wakeup(dev))
+ disable_irq_wake(priv->irq);
+ return ret;
+}
+
+static SIMPLE_DEV_PM_OPS(ti_k3_rtc_pm_ops, ti_k3_rtc_suspend, ti_k3_rtc_resume);
+
+static struct platform_driver ti_k3_rtc_driver = {
+ .probe = ti_k3_rtc_probe,
+ .driver = {
+ .name = "rtc-ti-k3",
+ .of_match_table = ti_k3_rtc_of_match_table,
+ .pm = &ti_k3_rtc_pm_ops,
+ },
+};
+module_platform_driver(ti_k3_rtc_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("TI K3 RTC driver");
+MODULE_AUTHOR("Nishanth Menon");