/* * This file is part of the coreboot project. * * Copyright 2014 Google Inc. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; version 2 of the License. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. */ #include #include #include #include #include #define PISTACHIO_CLOCK_SWITCH 0xB8144200 #define MIPS_EXTERN_PLL_BYPASS_MASK 0x00000002 static int get_count_mhz_freq(void) { static unsigned count_mhz_freq; if (!count_mhz_freq) { if (IMG_PLATFORM_ID() != IMG_PLATFORM_ID_SILICON) count_mhz_freq = 25; /* FPGA board */ else { /* If MIPS PLL external bypass bit is set, it means * that the MIPS PLL is already set up to work at a * frequency of 550 MHz; otherwise, the crystal is * used with a frequency of 52 MHz */ if (read32(PISTACHIO_CLOCK_SWITCH) & MIPS_EXTERN_PLL_BYPASS_MASK) /* Half MIPS PLL freq. */ count_mhz_freq = 275; else /* Half Xtal freq. */ count_mhz_freq = 26; } } return count_mhz_freq; } void timer_monotonic_get(struct mono_time *mt) { mono_time_set_usecs(mt, read_c0_count() / get_count_mhz_freq()); }