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Revision 2f8619846755176a6720c71d580ffd09394a74bc authored by Mian Yousaf Kaukab on 29 June 2021, 15:06:43 UTC, committed by Alexandre Belloni on 10 July 2021, 00:58:31 UTC 
rtc: pcf2127: handle timestamp interrupts
 
commit 03623b4b041c ("rtc: pcf2127: add tamper detection support")
added support for timestamp interrupts. However they are not being
handled in the irq handler. If a timestamp interrupt occurs it
results in kernel disabling the interrupt and displaying the call
trace:

[  121.145580] irq 78: nobody cared (try booting with the "irqpoll" option)
...
[  121.238087] [<00000000c4d69393>] irq_default_primary_handler threaded [<000000000a90d25b>] pcf2127_rtc_irq [rtc_pcf2127]
[  121.248971] Disabling IRQ #78

Handle timestamp interrupts in pcf2127_rtc_irq(). Save time stamp
before clearing TSF1 and TSF2 flags so that it can't be overwritten.
Set a flag to mark if the timestamp is valid and only report to sysfs
if the flag is set. To mimic the hardware behavior, don’t save
another timestamp until the first one has been read by the userspace.

However, if the alarm irq is not configured, keep the old way of
handling timestamp interrupt in the timestamp0 sysfs calls.

Signed-off-by: Mian Yousaf Kaukab <ykaukab@suse.de>
Reviewed-by: Bruno Thomsen <bruno.thomsen@gmail.com>
Tested-by: Bruno Thomsen <bruno.thomsen@gmail.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20210629150643.31551-1-ykaukab@suse.de
1 parent 37aadf9
Raw File
test_ida.c 
// SPDX-License-Identifier: GPL-2.0+
/*
 * test_ida.c: Test the IDA API
 * Copyright (c) 2016-2018 Microsoft Corporation
 * Copyright (c) 2018 Oracle Corporation
 * Author: Matthew Wilcox <willy@infradead.org>
 */

#include <linux/idr.h>
#include <linux/module.h>

static unsigned int tests_run;
static unsigned int tests_passed;

#ifdef __KERNEL__
void ida_dump(struct ida *ida) { }
#endif
#define IDA_BUG_ON(ida, x) do {						\
	tests_run++;							\
	if (x) {							\
		ida_dump(ida);						\
		dump_stack();						\
	} else {							\
		tests_passed++;						\
	}								\
} while (0)

/*
 * Straightforward checks that allocating and freeing IDs work.
 */
static void ida_check_alloc(struct ida *ida)
{
	int i, id;

	for (i = 0; i < 10000; i++)
		IDA_BUG_ON(ida, ida_alloc(ida, GFP_KERNEL) != i);

	ida_free(ida, 20);
	ida_free(ida, 21);
	for (i = 0; i < 3; i++) {
		id = ida_alloc(ida, GFP_KERNEL);
		IDA_BUG_ON(ida, id < 0);
		if (i == 2)
			IDA_BUG_ON(ida, id != 10000);
	}

	for (i = 0; i < 5000; i++)
		ida_free(ida, i);

	IDA_BUG_ON(ida, ida_alloc_min(ida, 5000, GFP_KERNEL) != 10001);
	ida_destroy(ida);

	IDA_BUG_ON(ida, !ida_is_empty(ida));
}

/* Destroy an IDA with a single entry at @base */
static void ida_check_destroy_1(struct ida *ida, unsigned int base)
{
	IDA_BUG_ON(ida, ida_alloc_min(ida, base, GFP_KERNEL) != base);
	IDA_BUG_ON(ida, ida_is_empty(ida));
	ida_destroy(ida);
	IDA_BUG_ON(ida, !ida_is_empty(ida));
}

/* Check that ida_destroy and ida_is_empty work */
static void ida_check_destroy(struct ida *ida)
{
	/* Destroy an already-empty IDA */
	IDA_BUG_ON(ida, !ida_is_empty(ida));
	ida_destroy(ida);
	IDA_BUG_ON(ida, !ida_is_empty(ida));

	ida_check_destroy_1(ida, 0);
	ida_check_destroy_1(ida, 1);
	ida_check_destroy_1(ida, 1023);
	ida_check_destroy_1(ida, 1024);
	ida_check_destroy_1(ida, 12345678);
}

/*
 * Check what happens when we fill a leaf and then delete it.  This may
 * discover mishandling of IDR_FREE.
 */
static void ida_check_leaf(struct ida *ida, unsigned int base)
{
	unsigned long i;

	for (i = 0; i < IDA_BITMAP_BITS; i++) {
		IDA_BUG_ON(ida, ida_alloc_min(ida, base, GFP_KERNEL) !=
				base + i);
	}

	ida_destroy(ida);
	IDA_BUG_ON(ida, !ida_is_empty(ida));

	IDA_BUG_ON(ida, ida_alloc(ida, GFP_KERNEL) != 0);
	IDA_BUG_ON(ida, ida_is_empty(ida));
	ida_free(ida, 0);
	IDA_BUG_ON(ida, !ida_is_empty(ida));
}

/*
 * Check allocations up to and slightly above the maximum allowed (2^31-1) ID.
 * Allocating up to 2^31-1 should succeed, and then allocating the next one
 * should fail.
 */
static void ida_check_max(struct ida *ida)
{
	unsigned long i, j;

	for (j = 1; j < 65537; j *= 2) {
		unsigned long base = (1UL << 31) - j;
		for (i = 0; i < j; i++) {
			IDA_BUG_ON(ida, ida_alloc_min(ida, base, GFP_KERNEL) !=
					base + i);
		}
		IDA_BUG_ON(ida, ida_alloc_min(ida, base, GFP_KERNEL) !=
				-ENOSPC);
		ida_destroy(ida);
		IDA_BUG_ON(ida, !ida_is_empty(ida));
	}
}

/*
 * Check handling of conversions between exceptional entries and full bitmaps.
 */
static void ida_check_conv(struct ida *ida)
{
	unsigned long i;

	for (i = 0; i < IDA_BITMAP_BITS * 2; i += IDA_BITMAP_BITS) {
		IDA_BUG_ON(ida, ida_alloc_min(ida, i + 1, GFP_KERNEL) != i + 1);
		IDA_BUG_ON(ida, ida_alloc_min(ida, i + BITS_PER_LONG,
					GFP_KERNEL) != i + BITS_PER_LONG);
		ida_free(ida, i + 1);
		ida_free(ida, i + BITS_PER_LONG);
		IDA_BUG_ON(ida, !ida_is_empty(ida));
	}

	for (i = 0; i < IDA_BITMAP_BITS * 2; i++)
		IDA_BUG_ON(ida, ida_alloc(ida, GFP_KERNEL) != i);
	for (i = IDA_BITMAP_BITS * 2; i > 0; i--)
		ida_free(ida, i - 1);
	IDA_BUG_ON(ida, !ida_is_empty(ida));

	for (i = 0; i < IDA_BITMAP_BITS + BITS_PER_LONG - 4; i++)
		IDA_BUG_ON(ida, ida_alloc(ida, GFP_KERNEL) != i);
	for (i = IDA_BITMAP_BITS + BITS_PER_LONG - 4; i > 0; i--)
		ida_free(ida, i - 1);
	IDA_BUG_ON(ida, !ida_is_empty(ida));
}

static DEFINE_IDA(ida);

static int ida_checks(void)
{
	IDA_BUG_ON(&ida, !ida_is_empty(&ida));
	ida_check_alloc(&ida);
	ida_check_destroy(&ida);
	ida_check_leaf(&ida, 0);
	ida_check_leaf(&ida, 1024);
	ida_check_leaf(&ida, 1024 * 64);
	ida_check_max(&ida);
	ida_check_conv(&ida);

	printk("IDA: %u of %u tests passed\n", tests_passed, tests_run);
	return (tests_run != tests_passed) ? 0 : -EINVAL;
}

static void ida_exit(void)
{
}

module_init(ida_checks);
module_exit(ida_exit);
MODULE_AUTHOR("Matthew Wilcox <willy@infradead.org>");
MODULE_LICENSE("GPL");
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