| Scott Wood | bbc6fac | 2007-08-27 13:46:38 -0500 | [diff] [blame] | 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 | } |