1 /* 2 * PowerQUICC II support functions 3 * 4 * Author: Scott Wood <scottwood@freescale.com> 5 * 6 * Copyright (c) 2007 Freescale Semiconductor, Inc. 7 * 8 * This program is free software; you can redistribute it and/or modify it 9 * under the terms of the GNU General Public License version 2 as published 10 * by the Free Software Foundation. 11 */ 12 13 #include "ops.h" 14 #include "types.h" 15 #include "fsl-soc.h" 16 #include "pq2.h" 17 #include "stdio.h" 18 #include "io.h" 19 20 #define PQ2_SCCR (0x10c80/4) /* System Clock Configuration Register */ 21 #define PQ2_SCMR (0x10c88/4) /* System Clock Mode Register */ 22 23 static int pq2_corecnf_map[] = { 24 3, 2, 2, 2, 4, 4, 5, 9, 6, 11, 8, 10, 3, 12, 7, -1, 25 6, 5, 13, 2, 14, 4, 15, 9, 0, 11, 8, 10, 16, 12, 7, -1 26 }; 27 28 /* Get various clocks from crystal frequency. 29 * Returns zero on failure and non-zero on success. 30 */ 31 int pq2_get_clocks(u32 crystal, u32 *sysfreq, u32 *corefreq, 32 u32 *timebase, u32 *brgfreq) 33 { 34 u32 *immr; 35 u32 sccr, scmr, mainclk, busclk; 36 int corecnf, busdf, plldf, pllmf, dfbrg; 37 38 immr = fsl_get_immr(); 39 if (!immr) { 40 printf("pq2_get_clocks: Couldn't get IMMR base.\r\n"); 41 return 0; 42 } 43 44 sccr = in_be32(&immr[PQ2_SCCR]); 45 scmr = in_be32(&immr[PQ2_SCMR]); 46 47 dfbrg = sccr & 3; 48 corecnf = (scmr >> 24) & 0x1f; 49 busdf = (scmr >> 20) & 0xf; 50 plldf = (scmr >> 12) & 1; 51 pllmf = scmr & 0xfff; 52 53 mainclk = crystal * (pllmf + 1) / (plldf + 1); 54 busclk = mainclk / (busdf + 1); 55 56 if (sysfreq) 57 *sysfreq = mainclk / 2; 58 if (timebase) 59 *timebase = busclk / 4; 60 if (brgfreq) 61 *brgfreq = mainclk / (1 << ((dfbrg + 1) * 2)); 62 63 if (corefreq) { 64 int coremult = pq2_corecnf_map[corecnf]; 65 66 if (coremult < 0) 67 *corefreq = mainclk / 2; 68 else if (coremult == 0) 69 return 0; 70 else 71 *corefreq = busclk * coremult / 2; 72 } 73 74 return 1; 75 } 76 77 /* Set common device tree fields based on the given clock frequencies. */ 78 void pq2_set_clocks(u32 sysfreq, u32 corefreq, u32 timebase, u32 brgfreq) 79 { 80 void *node; 81 82 dt_fixup_cpu_clocks(corefreq, timebase, sysfreq); 83 84 node = finddevice("/soc/cpm"); 85 if (node) 86 setprop(node, "clock-frequency", &sysfreq, 4); 87 88 node = finddevice("/soc/cpm/brg"); 89 if (node) 90 setprop(node, "clock-frequency", &brgfreq, 4); 91 } 92 93 int pq2_fixup_clocks(u32 crystal) 94 { 95 u32 sysfreq, corefreq, timebase, brgfreq; 96 97 if (!pq2_get_clocks(crystal, &sysfreq, &corefreq, &timebase, &brgfreq)) 98 return 0; 99 100 pq2_set_clocks(sysfreq, corefreq, timebase, brgfreq); 101 return 1; 102 } 103