1 /*- 2 * Copyright (c) 2013 Ian Lepore <ian@freebsd.org> 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 */ 26 27 #include "opt_platform.h" 28 29 #include <sys/cdefs.h> 30 __FBSDID("$FreeBSD$"); 31 32 #include <sys/param.h> 33 #include <sys/systm.h> 34 #include <sys/reboot.h> 35 #include <sys/devmap.h> 36 37 #include <vm/vm.h> 38 #include <vm/pmap.h> 39 40 #include <machine/armreg.h> 41 #include <machine/bus.h> 42 #include <machine/machdep.h> 43 44 #include <arm/freescale/imx/imx_machdep.h> 45 #include <arm/freescale/imx/imx_wdogreg.h> 46 47 SYSCTL_NODE(_hw, OID_AUTO, imx, CTLFLAG_RW, NULL, "i.MX container"); 48 49 static int last_reset_status; 50 SYSCTL_UINT(_hw_imx, OID_AUTO, last_reset_status, CTLFLAG_RD, 51 &last_reset_status, 0, "Last reset status register"); 52 53 SYSCTL_STRING(_hw_imx, OID_AUTO, last_reset_reason, CTLFLAG_RD, 54 "unknown", 0, "Last reset reason"); 55 56 /* 57 * This code which manipulates the watchdog hardware is here to implement 58 * cpu_reset() because the watchdog is the only way for software to reset the 59 * chip. Why here and not in imx_wdog.c? Because there's no requirement that 60 * the watchdog driver be compiled in, but it's nice to be able to reboot even 61 * if it's not. 62 */ 63 void 64 imx_wdog_cpu_reset(vm_offset_t wdcr_physaddr) 65 { 66 volatile uint16_t * pcr; 67 68 /* 69 * Trigger an immediate reset by clearing the SRS bit in the watchdog 70 * control register. The reset happens on the next cycle of the wdog 71 * 32KHz clock, so hang out in a spin loop until the reset takes effect. 72 * 73 * Imx6 erratum ERR004346 says the SRS bit has to be cleared twice 74 * within the same cycle of the 32khz clock to reliably trigger the 75 * reset. Writing it 3 times in a row ensures at least 2 of the writes 76 * happen in the same 32k clock cycle. 77 */ 78 if ((pcr = devmap_ptov(wdcr_physaddr, sizeof(*pcr))) == NULL) { 79 printf("cpu_reset() can't find its control register... locking up now."); 80 } else { 81 *pcr &= ~WDOG_CR_SRS; 82 *pcr &= ~WDOG_CR_SRS; 83 *pcr &= ~WDOG_CR_SRS; 84 } 85 for (;;) 86 continue; 87 } 88 89 void 90 imx_wdog_init_last_reset(vm_offset_t wdsr_phys) 91 { 92 volatile uint16_t * psr; 93 94 if ((psr = devmap_ptov(wdsr_phys, sizeof(*psr))) == NULL) 95 return; 96 last_reset_status = *psr; 97 if (last_reset_status & WDOG_RSR_SFTW) { 98 sysctl___hw_imx_last_reset_reason.oid_arg1 = "SoftwareReset"; 99 } else if (last_reset_status & WDOG_RSR_TOUT) { 100 sysctl___hw_imx_last_reset_reason.oid_arg1 = "WatchdogTimeout"; 101 } else if (last_reset_status & WDOG_RSR_POR) { 102 sysctl___hw_imx_last_reset_reason.oid_arg1 = "PowerOnReset"; 103 } 104 } 105 106 u_int 107 imx_soc_family(void) 108 { 109 return (imx_soc_type() >> IMXSOC_FAMSHIFT); 110 } 111 112 113