freebsd-dev/sys/arm/freescale/imx/imx_machdep.c
Pawel Biernacki 7029da5c36 Mark more nodes as CTLFLAG_MPSAFE or CTLFLAG_NEEDGIANT (17 of many)
r357614 added CTLFLAG_NEEDGIANT to make it easier to find nodes that are
still not MPSAFE (or already are but aren’t properly marked).
Use it in preparation for a general review of all nodes.

This is non-functional change that adds annotations to SYSCTL_NODE and
SYSCTL_PROC nodes using one of the soon-to-be-required flags.

Mark all obvious cases as MPSAFE.  All entries that haven't been marked
as MPSAFE before are by default marked as NEEDGIANT

Approved by:	kib (mentor, blanket)
Commented by:	kib, gallatin, melifaro
Differential Revision:	https://reviews.freebsd.org/D23718
2020-02-26 14:26:36 +00:00

134 lines
4.5 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright (c) 2013 Ian Lepore <ian@freebsd.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include "opt_platform.h"
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/reboot.h>
#include <sys/devmap.h>
#include <vm/vm.h>
#include <vm/pmap.h>
#include <machine/armreg.h>
#include <machine/bus.h>
#include <machine/cpu.h>
#include <machine/machdep.h>
#include <arm/freescale/imx/imx_machdep.h>
#include <arm/freescale/imx/imx_wdogreg.h>
SYSCTL_NODE(_hw, OID_AUTO, imx, CTLFLAG_RW | CTLFLAG_MPSAFE, NULL,
"i.MX container");
static int last_reset_status;
SYSCTL_UINT(_hw_imx, OID_AUTO, last_reset_status, CTLFLAG_RD,
&last_reset_status, 0, "Last reset status register");
SYSCTL_STRING(_hw_imx, OID_AUTO, last_reset_reason, CTLFLAG_RD,
"unknown", 0, "Last reset reason");
/*
* This code which manipulates the watchdog hardware is here to implement
* cpu_reset() because the watchdog is the only way for software to reset the
* chip. Why here and not in imx_wdog.c? Because there's no requirement that
* the watchdog driver be compiled in, but it's nice to be able to reboot even
* if it's not.
*/
void
imx_wdog_cpu_reset(vm_offset_t wdcr_physaddr)
{
volatile uint16_t cr, *pcr;
if ((pcr = devmap_ptov(wdcr_physaddr, sizeof(*pcr))) == NULL) {
printf("imx_wdog_cpu_reset(): "
"cannot find control register... locking up now.");
for (;;)
cpu_spinwait();
}
cr = *pcr;
/*
* If the watchdog hardware has been set up to trigger an external reset
* signal on watchdog timeout, then we do software-requested rebooting
* the same way, by asserting the external reset signal.
*
* Asserting external reset is supposed to result in some external
* component asserting the POR pin on the SoC, possibly after adjusting
* and stabilizing system voltages, or taking other system-wide reset
* actions. Just in case there is some kind of misconfiguration, we
* hang out and do nothing for a full second, then continue on into
* the code to assert a software reset as well.
*/
if (cr & WDOG_CR_WDT) {
cr &= ~WDOG_CR_WDA; /* Assert active-low ext reset bit. */
*pcr = cr;
DELAY(1000000);
printf("imx_wdog_cpu_reset(): "
"External reset failed, trying internal cpu-reset\n");
DELAY(10000); /* Time for printf to appear */
}
/*
* Imx6 erratum ERR004346 says the SRS bit has to be cleared twice
* within the same cycle of the 32khz clock to reliably trigger the
* reset. Writing it 3 times in a row ensures at least 2 of the writes
* happen in the same 32k clock cycle.
*/
cr &= ~WDOG_CR_SRS; /* Assert active-low software reset bit. */
*pcr = cr;
*pcr = cr;
*pcr = cr;
/* Reset happens on the next tick of the 32khz clock, wait for it. */
for (;;)
cpu_spinwait();
}
void
imx_wdog_init_last_reset(vm_offset_t wdsr_phys)
{
volatile uint16_t * psr;
if ((psr = devmap_ptov(wdsr_phys, sizeof(*psr))) == NULL)
return;
last_reset_status = *psr;
if (last_reset_status & WDOG_RSR_SFTW) {
sysctl___hw_imx_last_reset_reason.oid_arg1 = "SoftwareReset";
} else if (last_reset_status & WDOG_RSR_TOUT) {
sysctl___hw_imx_last_reset_reason.oid_arg1 = "WatchdogTimeout";
} else if (last_reset_status & WDOG_RSR_POR) {
sysctl___hw_imx_last_reset_reason.oid_arg1 = "PowerOnReset";
}
}