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authorJoel Fernandes <joelagnelf@nvidia.com>2026-07-18 13:15:36 -0400
committerPaul E. McKenney <paulmck@kernel.org>2026-07-23 10:39:57 -0700
commit34ff636f322c6d5e4f0a52338fa63a7dff09a495 (patch)
tree7629759c1ec7148b95bc8ab3080df20a5ecd2273 /drivers/rtc/rtc-m48t35.c
downloadlinux-stable-34ff636f322c6d5e4f0a52338fa63a7dff09a495.tar.gz
linux-stable-34ff636f322c6d5e4f0a52338fa63a7dff09a495.zip
scftorture: Count single_rpc offline failures in statistics outputgrafted
scf_torture_stats_print() aggregates each invoker thread's counters into a local scf_statistics structure before printing, but the n_single_rpc_ofl field is missing from the aggregation loop. As a result, the "single_rpc_ofl" value printed in the statistics line is always zero, even when smp_call_function_single() invocations for the RPC test have failed due to offline CPUs and been counted by the invoker threads. Add the missing accumulation so that the printed value reflects the actual counts. Signed-off-by: Joel Fernandes <joelagnelf@nvidia.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Diffstat (limited to 'drivers/rtc/rtc-m48t35.c')
-rw-r--r--drivers/rtc/rtc-m48t35.c193
1 files changed, 193 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-m48t35.c b/drivers/rtc/rtc-m48t35.c
new file mode 100644
index 000000000..92f19bf99
--- /dev/null
+++ b/drivers/rtc/rtc-m48t35.c
@@ -0,0 +1,193 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Driver for the SGS-Thomson M48T35 Timekeeper RAM chip
+ *
+ * Copyright (C) 2000 Silicon Graphics, Inc.
+ * Written by Ulf Carlsson (ulfc@engr.sgi.com)
+ *
+ * Copyright (C) 2008 Thomas Bogendoerfer
+ *
+ * Based on code written by Paul Gortmaker.
+ */
+
+#include <linux/module.h>
+#include <linux/rtc.h>
+#include <linux/slab.h>
+#include <linux/platform_device.h>
+#include <linux/bcd.h>
+#include <linux/io.h>
+#include <linux/err.h>
+
+struct m48t35_rtc {
+ u8 pad[0x7ff8]; /* starts at 0x7ff8 */
+#ifdef CONFIG_SGI_IP27
+ u8 hour;
+ u8 min;
+ u8 sec;
+ u8 control;
+ u8 year;
+ u8 month;
+ u8 date;
+ u8 day;
+#else
+ u8 control;
+ u8 sec;
+ u8 min;
+ u8 hour;
+ u8 day;
+ u8 date;
+ u8 month;
+ u8 year;
+#endif
+};
+
+#define M48T35_RTC_SET 0x80
+#define M48T35_RTC_READ 0x40
+
+struct m48t35_priv {
+ struct rtc_device *rtc;
+ struct m48t35_rtc __iomem *reg;
+ size_t size;
+ unsigned long baseaddr;
+ spinlock_t lock;
+};
+
+static int m48t35_read_time(struct device *dev, struct rtc_time *tm)
+{
+ struct m48t35_priv *priv = dev_get_drvdata(dev);
+ u8 control;
+
+ /*
+ * Only the values that we read from the RTC are set. We leave
+ * tm_wday, tm_yday and tm_isdst untouched. Even though the
+ * RTC has RTC_DAY_OF_WEEK, we ignore it, as it is only updated
+ * by the RTC when initially set to a non-zero value.
+ */
+ spin_lock_irq(&priv->lock);
+ control = readb(&priv->reg->control);
+ writeb(control | M48T35_RTC_READ, &priv->reg->control);
+ tm->tm_sec = readb(&priv->reg->sec);
+ tm->tm_min = readb(&priv->reg->min);
+ tm->tm_hour = readb(&priv->reg->hour);
+ tm->tm_mday = readb(&priv->reg->date);
+ tm->tm_mon = readb(&priv->reg->month);
+ tm->tm_year = readb(&priv->reg->year);
+ writeb(control, &priv->reg->control);
+ spin_unlock_irq(&priv->lock);
+
+ tm->tm_sec = bcd2bin(tm->tm_sec);
+ tm->tm_min = bcd2bin(tm->tm_min);
+ tm->tm_hour = bcd2bin(tm->tm_hour);
+ tm->tm_mday = bcd2bin(tm->tm_mday);
+ tm->tm_mon = bcd2bin(tm->tm_mon);
+ tm->tm_year = bcd2bin(tm->tm_year);
+
+ /*
+ * Account for differences between how the RTC uses the values
+ * and how they are defined in a struct rtc_time;
+ */
+ tm->tm_year += 70;
+ if (tm->tm_year <= 69)
+ tm->tm_year += 100;
+
+ tm->tm_mon--;
+ return 0;
+}
+
+static int m48t35_set_time(struct device *dev, struct rtc_time *tm)
+{
+ struct m48t35_priv *priv = dev_get_drvdata(dev);
+ unsigned char mon, day, hrs, min, sec;
+ unsigned int yrs;
+ u8 control;
+
+ yrs = tm->tm_year + 1900;
+ mon = tm->tm_mon + 1; /* tm_mon starts at zero */
+ day = tm->tm_mday;
+ hrs = tm->tm_hour;
+ min = tm->tm_min;
+ sec = tm->tm_sec;
+
+ if (yrs < 1970)
+ return -EINVAL;
+
+ yrs -= 1970;
+ if (yrs > 255) /* They are unsigned */
+ return -EINVAL;
+
+ if (yrs > 169)
+ return -EINVAL;
+
+ if (yrs >= 100)
+ yrs -= 100;
+
+ sec = bin2bcd(sec);
+ min = bin2bcd(min);
+ hrs = bin2bcd(hrs);
+ day = bin2bcd(day);
+ mon = bin2bcd(mon);
+ yrs = bin2bcd(yrs);
+
+ spin_lock_irq(&priv->lock);
+ control = readb(&priv->reg->control);
+ writeb(control | M48T35_RTC_SET, &priv->reg->control);
+ writeb(yrs, &priv->reg->year);
+ writeb(mon, &priv->reg->month);
+ writeb(day, &priv->reg->date);
+ writeb(hrs, &priv->reg->hour);
+ writeb(min, &priv->reg->min);
+ writeb(sec, &priv->reg->sec);
+ writeb(control, &priv->reg->control);
+ spin_unlock_irq(&priv->lock);
+ return 0;
+}
+
+static const struct rtc_class_ops m48t35_ops = {
+ .read_time = m48t35_read_time,
+ .set_time = m48t35_set_time,
+};
+
+static int m48t35_probe(struct platform_device *pdev)
+{
+ struct resource *res;
+ struct m48t35_priv *priv;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res)
+ return -ENODEV;
+ priv = devm_kzalloc(&pdev->dev, sizeof(struct m48t35_priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ priv->size = resource_size(res);
+ if (!devm_request_mem_region(&pdev->dev, res->start, priv->size,
+ pdev->name))
+ return -EBUSY;
+
+ priv->baseaddr = res->start;
+ priv->reg = devm_ioremap(&pdev->dev, priv->baseaddr, priv->size);
+ if (!priv->reg)
+ return -ENOMEM;
+
+ spin_lock_init(&priv->lock);
+
+ platform_set_drvdata(pdev, priv);
+
+ priv->rtc = devm_rtc_device_register(&pdev->dev, "m48t35",
+ &m48t35_ops, THIS_MODULE);
+ return PTR_ERR_OR_ZERO(priv->rtc);
+}
+
+static struct platform_driver m48t35_platform_driver = {
+ .driver = {
+ .name = "rtc-m48t35",
+ },
+ .probe = m48t35_probe,
+};
+
+module_platform_driver(m48t35_platform_driver);
+
+MODULE_AUTHOR("Thomas Bogendoerfer <tsbogend@alpha.franken.de>");
+MODULE_DESCRIPTION("M48T35 RTC driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:rtc-m48t35");