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authorLinus Torvalds <torvalds@linux-foundation.org>2026-09-13 12:27:00 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-09-13 12:27:00 -0700
commit22098763a10d9c1340827fcf6edab66f153b27f0 (patch)
tree3962f95a34df034652ff93686cdd156c7197f2d9 /drivers/rtc/rtc-mxc.c
downloadlinux-stable-22098763a10d9c1340827fcf6edab66f153b27f0.tar.gz
linux-stable-22098763a10d9c1340827fcf6edab66f153b27f0.zip
Merge tag 'trace-v7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted
Pull tracing fixes from Steven Rostedt: - Don't destroy user event fields when removal fails User event fields are destroyed before the event is removed from visibility. But that can fail leaving the still visible event with no fields. Move the destroying of the fields to after the event is successfully removed from visibility. - Initialize function graph state is fork before calling copy_exec_state() For non-CLONE_VM forks, copy_exec_state() allocates a new task_exec_state. If that allocation fails, ftrace_graph_exit_task() will free the tasks ret_stack pointer. Since that pointer is still using the parent's ret_stack, it mistakenly frees the parent's pointer too. Call ftrace_graph_init() on the task first which will NULL out the new tasks's ret_stack and if the copy fails, it will not free anything. - Remove FGRAPH_MAX_INDEX The macro FGRAPH_MAX_INDEX was added but never used. Remove it. - Save ent_size in function graph printing of nested functions The function graph tracer needs to look at the next event to see if the next event is the return of the current function entry. If it is, it prints a single line: ktime_get(); Otherwise it prints it like a nested function: tick_nohz_irq_exit() { ktime_get(); kcpustat_irq_exit(); } In order to look at the next event, it must save the current event so that it has the information to print from it. It saves the event in the iterator descriptor called "ent". What it doesn't save is the ent_size of the event which is now used to know if the function graph arguments are to be printed. The peek doesn't save the size so the size used happens to be that of the size of the last event that was seen. Save the entry event size in the iterator descriptor so that the correct size is used. - Fix several errors with freeing data in the histogram code The histogram code had a lot of leaked or or incorrect accounting when failures happen. Correct them. - Fix histogram regression of .percent and .graph modifiers Up until 6.3 histogram values could have "percent" or "graph" modifiers that changed how they were printed. But a change that added restricting histograms values from being strings, stack traces and other modifiers inadvertently prevented them from using the percent and graph modifiers, which were legal use cases for values. Put back the percent and graph modifiers. - Fix various typos in the comments - Set the trace_clock before initializing a histogram with clock argument The histogram API allows the user to specific which trace clock to use via a "clock=" string. The histogram is set up first before the clock is checked. If the passed in clock is not valid, it exits without fully fixing up the histogram leaving it on the list and a use-after-free can trigger. Update the clock argument first and if it fails then exit gracefully before the histogram trigger is placed on any lists. - Restore :mod: trailer after parsing in ftrace_set_clr_event The function ftrace_set_clr_event() modifies the parse string and needs to put it back to what was passed in. It searches for ":mod:" via a strsep() but fails to put back the first ':' in the string. Add back the ':' in the passed in string. - Take trace_array reference when opening a tracer options file The options files are dynamically created and some tracers add their own options. When a tracer adds their own list of options, the trace_array holding them has an array to hold the list of options for each tracer. This array increases in size via a krealloc(), and the new entry gets a newly allocated array to hold the options of the new tracer being added. The element in each entry of the tracer's option array holds a pointer back to the trace_array, a pointer to the tracer it is associated to, a pointer to the flags of the option. The issue is that these arrays are freed when the trace_array is freed when its instance it represents is removed from the instances directory. There's a race that an open of one of these options files can happen when the instance is being removed. Add a new helper function to be called by the open function of the options file to iterate all existing trace_arrays under a lock and find the one that has the given option element in one of it's tracer arrays. If found, then update the associated trace_array's reference counter to keep it from being freed. If not found, have the open call return -ENODEV. - Disable interrupts when acquiring the lock in rb_wake_up_waiters() The function rb_wake_up_waiters() assumes it will be called in interrupt context and does not disable irqs when taking cpu_buffer->reader_lock, which can be called in hard interrupt context. The issue is in PREEMPT_RT, this function is called in thread context leaving this lock open to a deadlock. Take the lock with interrupts disabled. - Use rcu_assign_pointer() for tmp_ops filter hash The tmp_ops used in update_ftrace_direct_mod() assigns its filter_hash field directly, but that field is annotated as __rcu and sparse complains. Assign it with rcu_assign_pointer() - Fix use-after-free in enable_trigger_private_data_free() The trace_event_call is accessed through the event_trigger_data's trace_event_file pointer to put the trace_event_call on freeing. The issue is that the trace_event_file data may have been freed already causing a use-after-free. Add a field to the event_trigger_data that points directly to the trace_event_call so that it can decrement its reference directly without needing to go through the trace_event_file. - Fix accounting of buffer data remote headers trace_buffer_desc_size() and trace_remote_alloc_buffer() undercount the number of pages is needed for the asked for size as it doesn't take into account the meta data on each page. Add a helper function to do the calculation properly and use that in these functions. - Catch nr_page_va overflow in ring_buffer_desc sizing The number of pages per remote ring buffer is capped by ring_buffer_desc::nr_page_va (32 bits). A buffer_size large enough to overflow that field would silently allocate a descriptor smaller than what was asked for. - Do not resize the subbuf order if any per_cpu buffer is disabled The mmapping of ring buffers disables resizing the subbuffers, but it is done per-cpu whereas the subbuf size change is done for all the per_cpu buffers under the buffer->mutex. It could change the size of some while the mapping is happening on others. Have the resize of the subbuf order check all the per_cpu buffers under the lock to see if any of them is disabled before starting and causing an inconsistency between buffers that are being mapped. * tag 'trace-v7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (25 commits) ring-buffer: Check resize_disabled before publishing the new subbuf order tracing/remotes: Catch nr_page_va overflow in ring_buffer_desc sizing tracing/remotes: Account for ring buffer page header in size calculation tracing: Don't dereference trace_event_file in deferred trigger free ftrace: Use rcu_assign_pointer() for tmp_ops filter hash ring-buffer: Acquire the lock with irqsave in rb_wake_up_waiters() tracing: Take trace_array reference when opening a tracer options file tracing: Fix ring_buffer_read_page_size() kernel-doc tracing: Restore :mod: trailer after parsing in ftrace_set_clr_event() tracing: Fix memory corruption from a "STACKTRACE" histogram key tracing: Fix memory corruption from the histogram stacktrace modifier tracing: Undo the registration when enabling the histogram trigger fails tracing: Take the reference before publishing the named histogram trigger tracing: Set the trace clock before registering the histogram trigger tracing: Fix typo "preceeded" in comment tracing: Fix typo "availabe" in comment tracing: Let histogram values keep the percent and graph modifiers tracing: Keep the entry count when the histogram stats allocation fails tracing: Free histogram the field rejected for a bad modifier tracing: Free histogram the var ref when its initialization fails ...
Diffstat (limited to 'drivers/rtc/rtc-mxc.c')
-rw-r--r--drivers/rtc/rtc-mxc.c404
1 files changed, 404 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-mxc.c b/drivers/rtc/rtc-mxc.c
new file mode 100644
index 000000000..608db97d4
--- /dev/null
+++ b/drivers/rtc/rtc-mxc.c
@@ -0,0 +1,404 @@
+// SPDX-License-Identifier: GPL-2.0+
+//
+// Copyright 2004-2008 Freescale Semiconductor, Inc. All Rights Reserved.
+
+#include <linux/io.h>
+#include <linux/rtc.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/pm_wakeirq.h>
+#include <linux/clk.h>
+#include <linux/of.h>
+
+#define RTC_INPUT_CLK_32768HZ (0x00 << 5)
+#define RTC_INPUT_CLK_32000HZ (0x01 << 5)
+#define RTC_INPUT_CLK_38400HZ (0x02 << 5)
+
+#define RTC_SW_BIT (1 << 0)
+#define RTC_ALM_BIT (1 << 2)
+#define RTC_1HZ_BIT (1 << 4)
+#define RTC_2HZ_BIT (1 << 7)
+#define RTC_SAM0_BIT (1 << 8)
+#define RTC_SAM1_BIT (1 << 9)
+#define RTC_SAM2_BIT (1 << 10)
+#define RTC_SAM3_BIT (1 << 11)
+#define RTC_SAM4_BIT (1 << 12)
+#define RTC_SAM5_BIT (1 << 13)
+#define RTC_SAM6_BIT (1 << 14)
+#define RTC_SAM7_BIT (1 << 15)
+#define PIT_ALL_ON (RTC_2HZ_BIT | RTC_SAM0_BIT | RTC_SAM1_BIT | \
+ RTC_SAM2_BIT | RTC_SAM3_BIT | RTC_SAM4_BIT | \
+ RTC_SAM5_BIT | RTC_SAM6_BIT | RTC_SAM7_BIT)
+
+#define RTC_ENABLE_BIT (1 << 7)
+
+#define MAX_PIE_NUM 9
+#define MAX_PIE_FREQ 512
+
+#define MXC_RTC_TIME 0
+#define MXC_RTC_ALARM 1
+
+#define RTC_HOURMIN 0x00 /* 32bit rtc hour/min counter reg */
+#define RTC_SECOND 0x04 /* 32bit rtc seconds counter reg */
+#define RTC_ALRM_HM 0x08 /* 32bit rtc alarm hour/min reg */
+#define RTC_ALRM_SEC 0x0C /* 32bit rtc alarm seconds reg */
+#define RTC_RTCCTL 0x10 /* 32bit rtc control reg */
+#define RTC_RTCISR 0x14 /* 32bit rtc interrupt status reg */
+#define RTC_RTCIENR 0x18 /* 32bit rtc interrupt enable reg */
+#define RTC_STPWCH 0x1C /* 32bit rtc stopwatch min reg */
+#define RTC_DAYR 0x20 /* 32bit rtc days counter reg */
+#define RTC_DAYALARM 0x24 /* 32bit rtc day alarm reg */
+#define RTC_TEST1 0x28 /* 32bit rtc test reg 1 */
+#define RTC_TEST2 0x2C /* 32bit rtc test reg 2 */
+#define RTC_TEST3 0x30 /* 32bit rtc test reg 3 */
+
+enum imx_rtc_type {
+ IMX1_RTC,
+ IMX21_RTC,
+};
+
+struct rtc_plat_data {
+ struct rtc_device *rtc;
+ void __iomem *ioaddr;
+ int irq;
+ struct clk *clk_ref;
+ struct clk *clk_ipg;
+ struct rtc_time g_rtc_alarm;
+ enum imx_rtc_type devtype;
+};
+
+static const struct of_device_id imx_rtc_dt_ids[] = {
+ { .compatible = "fsl,imx1-rtc", .data = (const void *)IMX1_RTC },
+ { .compatible = "fsl,imx21-rtc", .data = (const void *)IMX21_RTC },
+ {}
+};
+MODULE_DEVICE_TABLE(of, imx_rtc_dt_ids);
+
+static inline int is_imx1_rtc(struct rtc_plat_data *data)
+{
+ return data->devtype == IMX1_RTC;
+}
+
+/*
+ * This function is used to obtain the RTC time or the alarm value in
+ * second.
+ */
+static time64_t get_alarm_or_time(struct device *dev, int time_alarm)
+{
+ struct rtc_plat_data *pdata = dev_get_drvdata(dev);
+ void __iomem *ioaddr = pdata->ioaddr;
+ u32 day = 0, hr = 0, min = 0, sec = 0, hr_min = 0;
+
+ switch (time_alarm) {
+ case MXC_RTC_TIME:
+ day = readw(ioaddr + RTC_DAYR);
+ hr_min = readw(ioaddr + RTC_HOURMIN);
+ sec = readw(ioaddr + RTC_SECOND);
+ break;
+ case MXC_RTC_ALARM:
+ day = readw(ioaddr + RTC_DAYALARM);
+ hr_min = readw(ioaddr + RTC_ALRM_HM) & 0xffff;
+ sec = readw(ioaddr + RTC_ALRM_SEC);
+ break;
+ }
+
+ hr = hr_min >> 8;
+ min = hr_min & 0xff;
+
+ return ((((time64_t)day * 24 + hr) * 60) + min) * 60 + sec;
+}
+
+/*
+ * This function sets the RTC alarm value or the time value.
+ */
+static void set_alarm_or_time(struct device *dev, int time_alarm, time64_t time)
+{
+ u32 tod, day, hr, min, sec, temp;
+ struct rtc_plat_data *pdata = dev_get_drvdata(dev);
+ void __iomem *ioaddr = pdata->ioaddr;
+
+ day = div_s64_rem(time, 86400, &tod);
+
+ /* time is within a day now */
+ hr = tod / 3600;
+ tod -= hr * 3600;
+
+ /* time is within an hour now */
+ min = tod / 60;
+ sec = tod - min * 60;
+
+ temp = (hr << 8) + min;
+
+ switch (time_alarm) {
+ case MXC_RTC_TIME:
+ writew(day, ioaddr + RTC_DAYR);
+ writew(sec, ioaddr + RTC_SECOND);
+ writew(temp, ioaddr + RTC_HOURMIN);
+ break;
+ case MXC_RTC_ALARM:
+ writew(day, ioaddr + RTC_DAYALARM);
+ writew(sec, ioaddr + RTC_ALRM_SEC);
+ writew(temp, ioaddr + RTC_ALRM_HM);
+ break;
+ }
+}
+
+/*
+ * This function updates the RTC alarm registers and then clears all the
+ * interrupt status bits.
+ */
+static void rtc_update_alarm(struct device *dev, struct rtc_time *alrm)
+{
+ time64_t time;
+ struct rtc_plat_data *pdata = dev_get_drvdata(dev);
+ void __iomem *ioaddr = pdata->ioaddr;
+
+ time = rtc_tm_to_time64(alrm);
+
+ /* clear all the interrupt status bits */
+ writew(readw(ioaddr + RTC_RTCISR), ioaddr + RTC_RTCISR);
+ set_alarm_or_time(dev, MXC_RTC_ALARM, time);
+}
+
+static void mxc_rtc_irq_enable(struct device *dev, unsigned int bit,
+ unsigned int enabled)
+{
+ struct rtc_plat_data *pdata = dev_get_drvdata(dev);
+ void __iomem *ioaddr = pdata->ioaddr;
+ u32 reg;
+ unsigned long flags;
+
+ spin_lock_irqsave(&pdata->rtc->irq_lock, flags);
+ reg = readw(ioaddr + RTC_RTCIENR);
+
+ if (enabled)
+ reg |= bit;
+ else
+ reg &= ~bit;
+
+ writew(reg, ioaddr + RTC_RTCIENR);
+ spin_unlock_irqrestore(&pdata->rtc->irq_lock, flags);
+}
+
+/* This function is the RTC interrupt service routine. */
+static irqreturn_t mxc_rtc_interrupt(int irq, void *dev_id)
+{
+ struct platform_device *pdev = dev_id;
+ struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
+ void __iomem *ioaddr = pdata->ioaddr;
+ u32 status;
+ u32 events = 0;
+
+ spin_lock(&pdata->rtc->irq_lock);
+ status = readw(ioaddr + RTC_RTCISR) & readw(ioaddr + RTC_RTCIENR);
+ /* clear interrupt sources */
+ writew(status, ioaddr + RTC_RTCISR);
+
+ /* update irq data & counter */
+ if (status & RTC_ALM_BIT) {
+ events |= (RTC_AF | RTC_IRQF);
+ /* RTC alarm should be one-shot */
+ mxc_rtc_irq_enable(&pdev->dev, RTC_ALM_BIT, 0);
+ }
+
+ if (status & PIT_ALL_ON)
+ events |= (RTC_PF | RTC_IRQF);
+
+ rtc_update_irq(pdata->rtc, 1, events);
+ spin_unlock(&pdata->rtc->irq_lock);
+
+ return IRQ_HANDLED;
+}
+
+static int mxc_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
+{
+ mxc_rtc_irq_enable(dev, RTC_ALM_BIT, enabled);
+ return 0;
+}
+
+/*
+ * This function reads the current RTC time into tm in Gregorian date.
+ */
+static int mxc_rtc_read_time(struct device *dev, struct rtc_time *tm)
+{
+ time64_t val;
+
+ /* Avoid roll-over from reading the different registers */
+ do {
+ val = get_alarm_or_time(dev, MXC_RTC_TIME);
+ } while (val != get_alarm_or_time(dev, MXC_RTC_TIME));
+
+ rtc_time64_to_tm(val, tm);
+
+ return 0;
+}
+
+/*
+ * This function sets the internal RTC time based on tm in Gregorian date.
+ */
+static int mxc_rtc_set_time(struct device *dev, struct rtc_time *tm)
+{
+ time64_t time = rtc_tm_to_time64(tm);
+
+ /* Avoid roll-over from reading the different registers */
+ do {
+ set_alarm_or_time(dev, MXC_RTC_TIME, time);
+ } while (time != get_alarm_or_time(dev, MXC_RTC_TIME));
+
+ return 0;
+}
+
+/*
+ * This function reads the current alarm value into the passed in 'alrm'
+ * argument. It updates the alrm's pending field value based on the whether
+ * an alarm interrupt occurs or not.
+ */
+static int mxc_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+ struct rtc_plat_data *pdata = dev_get_drvdata(dev);
+ void __iomem *ioaddr = pdata->ioaddr;
+
+ rtc_time64_to_tm(get_alarm_or_time(dev, MXC_RTC_ALARM), &alrm->time);
+ alrm->pending = ((readw(ioaddr + RTC_RTCISR) & RTC_ALM_BIT)) ? 1 : 0;
+
+ return 0;
+}
+
+/*
+ * This function sets the RTC alarm based on passed in alrm.
+ */
+static int mxc_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+ struct rtc_plat_data *pdata = dev_get_drvdata(dev);
+
+ rtc_update_alarm(dev, &alrm->time);
+
+ memcpy(&pdata->g_rtc_alarm, &alrm->time, sizeof(struct rtc_time));
+ mxc_rtc_irq_enable(dev, RTC_ALM_BIT, alrm->enabled);
+
+ return 0;
+}
+
+/* RTC layer */
+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_probe(struct platform_device *pdev)
+{
+ struct rtc_device *rtc;
+ struct rtc_plat_data *pdata = NULL;
+ u32 reg;
+ unsigned long rate;
+ int ret;
+
+ pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
+ if (!pdata)
+ return -ENOMEM;
+
+ pdata->devtype = (uintptr_t)of_device_get_match_data(&pdev->dev);
+
+ pdata->ioaddr = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(pdata->ioaddr))
+ return PTR_ERR(pdata->ioaddr);
+
+ rtc = devm_rtc_allocate_device(&pdev->dev);
+ if (IS_ERR(rtc))
+ return PTR_ERR(rtc);
+
+ pdata->rtc = rtc;
+ rtc->ops = &mxc_rtc_ops;
+ if (is_imx1_rtc(pdata)) {
+ struct rtc_time tm;
+
+ /* 9bit days + hours minutes seconds */
+ rtc->range_max = (1 << 9) * 86400 - 1;
+
+ /*
+ * Set the start date as beginning of the current year. This can
+ * be overridden using device tree.
+ */
+ rtc_time64_to_tm(ktime_get_real_seconds(), &tm);
+ rtc->start_secs = mktime64(tm.tm_year, 1, 1, 0, 0, 0);
+ rtc->set_start_time = true;
+ } else {
+ /* 16bit days + hours minutes seconds */
+ rtc->range_max = (1 << 16) * 86400ULL - 1;
+ }
+
+ pdata->clk_ipg = devm_clk_get_enabled(&pdev->dev, "ipg");
+ if (IS_ERR(pdata->clk_ipg)) {
+ dev_err(&pdev->dev, "unable to get ipg clock!\n");
+ return PTR_ERR(pdata->clk_ipg);
+ }
+
+ pdata->clk_ref = devm_clk_get_enabled(&pdev->dev, "ref");
+ if (IS_ERR(pdata->clk_ref)) {
+ dev_err(&pdev->dev, "unable to get ref clock!\n");
+ return PTR_ERR(pdata->clk_ref);
+ }
+
+ rate = clk_get_rate(pdata->clk_ref);
+
+ if (rate == 32768)
+ reg = RTC_INPUT_CLK_32768HZ;
+ else if (rate == 32000)
+ reg = RTC_INPUT_CLK_32000HZ;
+ else if (rate == 38400)
+ reg = RTC_INPUT_CLK_38400HZ;
+ else {
+ dev_err(&pdev->dev, "rtc clock is not valid (%lu)\n", rate);
+ return -EINVAL;
+ }
+
+ reg |= RTC_ENABLE_BIT;
+ writew(reg, (pdata->ioaddr + RTC_RTCCTL));
+ if (((readw(pdata->ioaddr + RTC_RTCCTL)) & RTC_ENABLE_BIT) == 0) {
+ dev_err(&pdev->dev, "hardware module can't be enabled!\n");
+ return -EIO;
+ }
+
+ platform_set_drvdata(pdev, pdata);
+
+ /* Configure and enable the RTC */
+ pdata->irq = platform_get_irq(pdev, 0);
+
+ if (pdata->irq >= 0 &&
+ devm_request_irq(&pdev->dev, pdata->irq, mxc_rtc_interrupt,
+ IRQF_SHARED, pdev->name, pdev) < 0) {
+ dev_warn(&pdev->dev, "interrupt not available.\n");
+ pdata->irq = -1;
+ }
+
+ if (pdata->irq >= 0) {
+ 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 = devm_rtc_register_device(rtc);
+
+ return ret;
+}
+
+static struct platform_driver mxc_rtc_driver = {
+ .driver = {
+ .name = "mxc_rtc",
+ .of_match_table = imx_rtc_dt_ids,
+ },
+ .probe = mxc_rtc_probe,
+};
+
+module_platform_driver(mxc_rtc_driver)
+
+MODULE_AUTHOR("Daniel Mack <daniel@caiaq.de>");
+MODULE_DESCRIPTION("RTC driver for Freescale MXC");
+MODULE_LICENSE("GPL");
+