Revision 0432a0a066b05361b6d4d26522233c3c76c9e5da authored by Linus Torvalds on 03 August 2019, 17:51:29 UTC, committed by Linus Torvalds on 03 August 2019, 17:51:29 UTC
Pull vdso timer fixes from Thomas Gleixner:
 "A series of commits to deal with the regression caused by the generic
  VDSO implementation.

  The usage of clock_gettime64() for 32bit compat fallback syscalls
  caused seccomp filters to kill innocent processes because they only
  allow clock_gettime().

  Handle the compat syscalls with clock_gettime() as before, which is
  not a functional problem for the VDSO as the legacy compat application
  interface is not y2038 safe anyway. It's just extra fallback code
  which needs to be implemented on every architecture.

  It's opt in for now so that it does not break the compile of already
  converted architectures in linux-next. Once these are fixed, the
  #ifdeffery goes away.

  So much for trying to be smart and reuse code..."

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  arm64: compat: vdso: Use legacy syscalls as fallback
  x86/vdso/32: Use 32bit syscall fallback
  lib/vdso/32: Provide legacy syscall fallbacks
  lib/vdso: Move fallback invocation to the callers
  lib/vdso/32: Remove inconsistent NULL pointer checks
2 parent s af42e74 + 33a5898
Raw File
stmp_device.c
// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Copyright (C) 1999 ARM Limited
 * Copyright (C) 2000 Deep Blue Solutions Ltd
 * Copyright 2006-2007,2010 Freescale Semiconductor, Inc. All Rights Reserved.
 * Copyright 2008 Juergen Beisert, kernel@pengutronix.de
 * Copyright 2009 Ilya Yanok, Emcraft Systems Ltd, yanok@emcraft.com
 * Copyright (C) 2011 Wolfram Sang, Pengutronix e.K.
 */

#include <linux/io.h>
#include <linux/errno.h>
#include <linux/delay.h>
#include <linux/compiler.h>
#include <linux/export.h>
#include <linux/stmp_device.h>

#define STMP_MODULE_CLKGATE	(1 << 30)
#define STMP_MODULE_SFTRST	(1 << 31)

/*
 * Clear the bit and poll it cleared.  This is usually called with
 * a reset address and mask being either SFTRST(bit 31) or CLKGATE
 * (bit 30).
 */
static int stmp_clear_poll_bit(void __iomem *addr, u32 mask)
{
	int timeout = 0x400;

	writel(mask, addr + STMP_OFFSET_REG_CLR);
	udelay(1);
	while ((readl(addr) & mask) && --timeout)
		/* nothing */;

	return !timeout;
}

int stmp_reset_block(void __iomem *reset_addr)
{
	int ret;
	int timeout = 0x400;

	/* clear and poll SFTRST */
	ret = stmp_clear_poll_bit(reset_addr, STMP_MODULE_SFTRST);
	if (unlikely(ret))
		goto error;

	/* clear CLKGATE */
	writel(STMP_MODULE_CLKGATE, reset_addr + STMP_OFFSET_REG_CLR);

	/* set SFTRST to reset the block */
	writel(STMP_MODULE_SFTRST, reset_addr + STMP_OFFSET_REG_SET);
	udelay(1);

	/* poll CLKGATE becoming set */
	while ((!(readl(reset_addr) & STMP_MODULE_CLKGATE)) && --timeout)
		/* nothing */;
	if (unlikely(!timeout))
		goto error;

	/* clear and poll SFTRST */
	ret = stmp_clear_poll_bit(reset_addr, STMP_MODULE_SFTRST);
	if (unlikely(ret))
		goto error;

	/* clear and poll CLKGATE */
	ret = stmp_clear_poll_bit(reset_addr, STMP_MODULE_CLKGATE);
	if (unlikely(ret))
		goto error;

	return 0;

error:
	pr_err("%s(%p): module reset timeout\n", __func__, reset_addr);
	return -ETIMEDOUT;
}
EXPORT_SYMBOL(stmp_reset_block);
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