1 /* 2 * IMX31 Clock Control Module 3 * 4 * Copyright (C) 2012 NICTA 5 * Updated by Jean-Christophe Dubois <jcd@tribudubois.net> 6 * 7 * This work is licensed under the terms of the GNU GPL, version 2 or later. 8 * See the COPYING file in the top-level directory. 9 * 10 * This is an abstract base class used to get a common interface to 11 * retrieve the CCM frequencies from the various i.MX SOC. 12 */ 13 14 #include "qemu/osdep.h" 15 #include "hw/misc/imx_ccm.h" 16 #include "qemu/log.h" 17 #include "qemu/module.h" 18 19 #ifndef DEBUG_IMX_CCM 20 #define DEBUG_IMX_CCM 0 21 #endif 22 23 #define DPRINTF(fmt, args...) \ 24 do { \ 25 if (DEBUG_IMX_CCM) { \ 26 fprintf(stderr, "[%s]%s: " fmt , TYPE_IMX_CCM, \ 27 __func__, ##args); \ 28 } \ 29 } while (0) 30 31 32 uint32_t imx_ccm_get_clock_frequency(IMXCCMState *dev, IMXClk clock) 33 { 34 uint32_t freq = 0; 35 IMXCCMClass *klass = IMX_GET_CLASS(dev); 36 37 if (klass->get_clock_frequency) { 38 freq = klass->get_clock_frequency(dev, clock); 39 } 40 41 DPRINTF("(clock = %d) = %d\n", clock, freq); 42 43 return freq; 44 } 45 46 /* 47 * Calculate PLL output frequency 48 */ 49 uint32_t imx_ccm_calc_pll(uint32_t pllreg, uint32_t base_freq) 50 { 51 int32_t freq; 52 int32_t mfn = MFN(pllreg); /* Numerator */ 53 uint32_t mfi = MFI(pllreg); /* Integer part */ 54 uint32_t mfd = 1 + MFD(pllreg); /* Denominator */ 55 uint32_t pd = 1 + PD(pllreg); /* Pre-divider */ 56 57 if (mfi < 5) { 58 mfi = 5; 59 } 60 61 /* mfn is 10-bit signed twos-complement */ 62 mfn <<= 32 - 10; 63 mfn >>= 32 - 10; 64 65 freq = ((2 * (base_freq >> 10) * (mfi * mfd + mfn)) / 66 (mfd * pd)) << 10; 67 68 DPRINTF("(pllreg = 0x%08x, base_freq = %d) = %d\n", pllreg, base_freq, 69 freq); 70 71 return freq; 72 } 73 74 static const TypeInfo imx_ccm_info = { 75 .name = TYPE_IMX_CCM, 76 .parent = TYPE_SYS_BUS_DEVICE, 77 .instance_size = sizeof(IMXCCMState), 78 .class_size = sizeof(IMXCCMClass), 79 .abstract = true, 80 }; 81 82 static void imx_ccm_register_types(void) 83 { 84 type_register_static(&imx_ccm_info); 85 } 86 87 type_init(imx_ccm_register_types) 88