1 /* $NetBSD: ti_cpufreq.c,v 1.2 2019/10/29 10:54:10 jmcneill Exp $ */ 2 3 /*- 4 * Copyright (c) 2019 Jared McNeill <jmcneill@invisible.ca> 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 21 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 22 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 23 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 24 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 29 #include "opt_soc.h" 30 31 #include <sys/cdefs.h> 32 __KERNEL_RCSID(0, "$NetBSD: ti_cpufreq.c,v 1.2 2019/10/29 10:54:10 jmcneill Exp $"); 33 34 #include <sys/param.h> 35 #include <sys/systm.h> 36 #include <sys/device.h> 37 #include <sys/kmem.h> 38 #include <sys/bus.h> 39 40 #include <dev/fdt/fdtvar.h> 41 #include <dev/fdt/syscon.h> 42 43 static bool ti_opp_probed = false; 44 static bool (*ti_opp_supportedfn)(const int, const int); 45 static struct syscon *ti_opp_syscon; 46 47 #ifdef SOC_AM33XX 48 49 #define AM33XX_REV_OFFSET 0x0600 50 #define AM33XX_REV_MASK 0xf0000000 51 #define AM33XX_EFUSE_OFFSET 0x07fc 52 #define AM33XX_EFUSE_MASK 0x00001fff 53 #define AM33XX_EFUSE_DEFAULT 0x1e2f 54 55 static const char * const am33xx_compatible[] = { "ti,am33xx", NULL }; 56 57 static bool 58 am33xx_opp_supported(const int opp_table, const int opp_node) 59 { 60 const u_int *supported_hw; 61 uint32_t efuse, rev; 62 int len; 63 64 syscon_lock(ti_opp_syscon); 65 rev = __SHIFTOUT(syscon_read_4(ti_opp_syscon, AM33XX_REV_OFFSET), AM33XX_REV_MASK); 66 efuse = __SHIFTOUT(syscon_read_4(ti_opp_syscon, AM33XX_EFUSE_OFFSET), AM33XX_EFUSE_MASK); 67 syscon_unlock(ti_opp_syscon); 68 69 if (efuse == 0) 70 efuse = AM33XX_EFUSE_DEFAULT; 71 efuse = ~efuse; 72 73 supported_hw = fdtbus_get_prop(opp_node, "opp-supported-hw", &len); 74 if (len != 8) 75 return false; 76 77 if ((rev & be32toh(supported_hw[0])) == 0) 78 return false; 79 80 if ((efuse & be32toh(supported_hw[1])) == 0) 81 return false; 82 83 return true; 84 } 85 #endif 86 87 static void 88 ti_opp_probe(const int opp_table) 89 { 90 if (ti_opp_probed) 91 return; 92 ti_opp_probed = true; 93 94 ti_opp_syscon = fdtbus_syscon_acquire(opp_table, "syscon"); 95 96 #ifdef SOC_AM33XX 97 if (ti_opp_syscon && of_match_compatible(OF_finddevice("/"), am33xx_compatible)) 98 ti_opp_supportedfn = am33xx_opp_supported; 99 #endif 100 } 101 102 static bool 103 ti_opp_supported(const int opp_table, const int opp_node) 104 { 105 ti_opp_probe(opp_table); 106 107 if (!of_hasprop(opp_node, "opp-supported-hw")) 108 return true; 109 110 return ti_opp_supportedfn ? ti_opp_supportedfn(opp_table, opp_node) : false; 111 } 112 113 FDT_OPP(ti, "operating-points-v2-ti-cpu", ti_opp_supported); 114