| 1 | /* $NetBSD: nouveau_subdev_clock_pllnv04.c,v 1.1.1.1 2014/08/06 12:36:29 riastradh Exp $ */ |
| 2 | |
| 3 | /* |
| 4 | * Copyright 1993-2003 NVIDIA, Corporation |
| 5 | * Copyright 2007-2009 Stuart Bennett |
| 6 | * |
| 7 | * Permission is hereby granted, free of charge, to any person obtaining a |
| 8 | * copy of this software and associated documentation files (the "Software"), |
| 9 | * to deal in the Software without restriction, including without limitation |
| 10 | * the rights to use, copy, modify, merge, publish, distribute, sublicense, |
| 11 | * and/or sell copies of the Software, and to permit persons to whom the |
| 12 | * Software is furnished to do so, subject to the following conditions: |
| 13 | * |
| 14 | * The above copyright notice and this permission notice shall be included in |
| 15 | * all copies or substantial portions of the Software. |
| 16 | * |
| 17 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| 18 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| 19 | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL |
| 20 | * THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, |
| 21 | * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF |
| 22 | * OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE |
| 23 | * SOFTWARE. |
| 24 | */ |
| 25 | |
| 26 | #include <sys/cdefs.h> |
| 27 | __KERNEL_RCSID(0, "$NetBSD: nouveau_subdev_clock_pllnv04.c,v 1.1.1.1 2014/08/06 12:36:29 riastradh Exp $" ); |
| 28 | |
| 29 | #include <subdev/bios.h> |
| 30 | #include <subdev/bios/pll.h> |
| 31 | |
| 32 | #include "pll.h" |
| 33 | |
| 34 | static int |
| 35 | getMNP_single(struct nouveau_subdev *subdev, struct nvbios_pll *info, int clk, |
| 36 | int *pN, int *pM, int *pP) |
| 37 | { |
| 38 | /* Find M, N and P for a single stage PLL |
| 39 | * |
| 40 | * Note that some bioses (NV3x) have lookup tables of precomputed MNP |
| 41 | * values, but we're too lazy to use those atm |
| 42 | * |
| 43 | * "clk" parameter in kHz |
| 44 | * returns calculated clock |
| 45 | */ |
| 46 | struct nouveau_bios *bios = nouveau_bios(subdev); |
| 47 | int minvco = info->vco1.min_freq, maxvco = info->vco1.max_freq; |
| 48 | int minM = info->vco1.min_m, maxM = info->vco1.max_m; |
| 49 | int minN = info->vco1.min_n, maxN = info->vco1.max_n; |
| 50 | int minU = info->vco1.min_inputfreq; |
| 51 | int maxU = info->vco1.max_inputfreq; |
| 52 | int minP = info->min_p; |
| 53 | int maxP = info->max_p_usable; |
| 54 | int crystal = info->refclk; |
| 55 | int M, N, thisP, P; |
| 56 | int clkP, calcclk; |
| 57 | int delta, bestdelta = INT_MAX; |
| 58 | int bestclk = 0; |
| 59 | |
| 60 | /* this division verified for nv20, nv18, nv28 (Haiku), and nv34 */ |
| 61 | /* possibly correlated with introduction of 27MHz crystal */ |
| 62 | if (bios->version.major < 0x60) { |
| 63 | int cv = bios->version.chip; |
| 64 | if (cv < 0x17 || cv == 0x1a || cv == 0x20) { |
| 65 | if (clk > 250000) |
| 66 | maxM = 6; |
| 67 | if (clk > 340000) |
| 68 | maxM = 2; |
| 69 | } else if (cv < 0x40) { |
| 70 | if (clk > 150000) |
| 71 | maxM = 6; |
| 72 | if (clk > 200000) |
| 73 | maxM = 4; |
| 74 | if (clk > 340000) |
| 75 | maxM = 2; |
| 76 | } |
| 77 | } |
| 78 | |
| 79 | P = 1 << maxP; |
| 80 | if ((clk * P) < minvco) { |
| 81 | minvco = clk * maxP; |
| 82 | maxvco = minvco * 2; |
| 83 | } |
| 84 | |
| 85 | if (clk + clk/200 > maxvco) /* +0.5% */ |
| 86 | maxvco = clk + clk/200; |
| 87 | |
| 88 | /* NV34 goes maxlog2P->0, NV20 goes 0->maxlog2P */ |
| 89 | for (thisP = minP; thisP <= maxP; thisP++) { |
| 90 | P = 1 << thisP; |
| 91 | clkP = clk * P; |
| 92 | |
| 93 | if (clkP < minvco) |
| 94 | continue; |
| 95 | if (clkP > maxvco) |
| 96 | return bestclk; |
| 97 | |
| 98 | for (M = minM; M <= maxM; M++) { |
| 99 | if (crystal/M < minU) |
| 100 | return bestclk; |
| 101 | if (crystal/M > maxU) |
| 102 | continue; |
| 103 | |
| 104 | /* add crystal/2 to round better */ |
| 105 | N = (clkP * M + crystal/2) / crystal; |
| 106 | |
| 107 | if (N < minN) |
| 108 | continue; |
| 109 | if (N > maxN) |
| 110 | break; |
| 111 | |
| 112 | /* more rounding additions */ |
| 113 | calcclk = ((N * crystal + P/2) / P + M/2) / M; |
| 114 | delta = abs(calcclk - clk); |
| 115 | /* we do an exhaustive search rather than terminating |
| 116 | * on an optimality condition... |
| 117 | */ |
| 118 | if (delta < bestdelta) { |
| 119 | bestdelta = delta; |
| 120 | bestclk = calcclk; |
| 121 | *pN = N; |
| 122 | *pM = M; |
| 123 | *pP = thisP; |
| 124 | if (delta == 0) /* except this one */ |
| 125 | return bestclk; |
| 126 | } |
| 127 | } |
| 128 | } |
| 129 | |
| 130 | return bestclk; |
| 131 | } |
| 132 | |
| 133 | static int |
| 134 | getMNP_double(struct nouveau_subdev *subdev, struct nvbios_pll *info, int clk, |
| 135 | int *pN1, int *pM1, int *pN2, int *pM2, int *pP) |
| 136 | { |
| 137 | /* Find M, N and P for a two stage PLL |
| 138 | * |
| 139 | * Note that some bioses (NV30+) have lookup tables of precomputed MNP |
| 140 | * values, but we're too lazy to use those atm |
| 141 | * |
| 142 | * "clk" parameter in kHz |
| 143 | * returns calculated clock |
| 144 | */ |
| 145 | int chip_version = nouveau_bios(subdev)->version.chip; |
| 146 | int minvco1 = info->vco1.min_freq, maxvco1 = info->vco1.max_freq; |
| 147 | int minvco2 = info->vco2.min_freq, maxvco2 = info->vco2.max_freq; |
| 148 | int minU1 = info->vco1.min_inputfreq, minU2 = info->vco2.min_inputfreq; |
| 149 | int maxU1 = info->vco1.max_inputfreq, maxU2 = info->vco2.max_inputfreq; |
| 150 | int minM1 = info->vco1.min_m, maxM1 = info->vco1.max_m; |
| 151 | int minN1 = info->vco1.min_n, maxN1 = info->vco1.max_n; |
| 152 | int minM2 = info->vco2.min_m, maxM2 = info->vco2.max_m; |
| 153 | int minN2 = info->vco2.min_n, maxN2 = info->vco2.max_n; |
| 154 | int maxlog2P = info->max_p_usable; |
| 155 | int crystal = info->refclk; |
| 156 | bool fixedgain2 = (minM2 == maxM2 && minN2 == maxN2); |
| 157 | int M1, N1, M2, N2, log2P; |
| 158 | int clkP, calcclk1, calcclk2, calcclkout; |
| 159 | int delta, bestdelta = INT_MAX; |
| 160 | int bestclk = 0; |
| 161 | |
| 162 | int vco2 = (maxvco2 - maxvco2/200) / 2; |
| 163 | for (log2P = 0; clk && log2P < maxlog2P && clk <= (vco2 >> log2P); log2P++) |
| 164 | ; |
| 165 | clkP = clk << log2P; |
| 166 | |
| 167 | if (maxvco2 < clk + clk/200) /* +0.5% */ |
| 168 | maxvco2 = clk + clk/200; |
| 169 | |
| 170 | for (M1 = minM1; M1 <= maxM1; M1++) { |
| 171 | if (crystal/M1 < minU1) |
| 172 | return bestclk; |
| 173 | if (crystal/M1 > maxU1) |
| 174 | continue; |
| 175 | |
| 176 | for (N1 = minN1; N1 <= maxN1; N1++) { |
| 177 | calcclk1 = crystal * N1 / M1; |
| 178 | if (calcclk1 < minvco1) |
| 179 | continue; |
| 180 | if (calcclk1 > maxvco1) |
| 181 | break; |
| 182 | |
| 183 | for (M2 = minM2; M2 <= maxM2; M2++) { |
| 184 | if (calcclk1/M2 < minU2) |
| 185 | break; |
| 186 | if (calcclk1/M2 > maxU2) |
| 187 | continue; |
| 188 | |
| 189 | /* add calcclk1/2 to round better */ |
| 190 | N2 = (clkP * M2 + calcclk1/2) / calcclk1; |
| 191 | if (N2 < minN2) |
| 192 | continue; |
| 193 | if (N2 > maxN2) |
| 194 | break; |
| 195 | |
| 196 | if (!fixedgain2) { |
| 197 | if (chip_version < 0x60) |
| 198 | if (N2/M2 < 4 || N2/M2 > 10) |
| 199 | continue; |
| 200 | |
| 201 | calcclk2 = calcclk1 * N2 / M2; |
| 202 | if (calcclk2 < minvco2) |
| 203 | break; |
| 204 | if (calcclk2 > maxvco2) |
| 205 | continue; |
| 206 | } else |
| 207 | calcclk2 = calcclk1; |
| 208 | |
| 209 | calcclkout = calcclk2 >> log2P; |
| 210 | delta = abs(calcclkout - clk); |
| 211 | /* we do an exhaustive search rather than terminating |
| 212 | * on an optimality condition... |
| 213 | */ |
| 214 | if (delta < bestdelta) { |
| 215 | bestdelta = delta; |
| 216 | bestclk = calcclkout; |
| 217 | *pN1 = N1; |
| 218 | *pM1 = M1; |
| 219 | *pN2 = N2; |
| 220 | *pM2 = M2; |
| 221 | *pP = log2P; |
| 222 | if (delta == 0) /* except this one */ |
| 223 | return bestclk; |
| 224 | } |
| 225 | } |
| 226 | } |
| 227 | } |
| 228 | |
| 229 | return bestclk; |
| 230 | } |
| 231 | |
| 232 | int |
| 233 | nv04_pll_calc(struct nouveau_subdev *subdev, struct nvbios_pll *info, u32 freq, |
| 234 | int *N1, int *M1, int *N2, int *M2, int *P) |
| 235 | { |
| 236 | int ret; |
| 237 | |
| 238 | if (!info->vco2.max_freq || !N2) { |
| 239 | ret = getMNP_single(subdev, info, freq, N1, M1, P); |
| 240 | if (N2) { |
| 241 | *N2 = 1; |
| 242 | *M2 = 1; |
| 243 | } |
| 244 | } else { |
| 245 | ret = getMNP_double(subdev, info, freq, N1, M1, N2, M2, P); |
| 246 | } |
| 247 | |
| 248 | if (!ret) |
| 249 | nv_error(subdev, "unable to compute acceptable pll values\n" ); |
| 250 | return ret; |
| 251 | } |
| 252 | |