diff options
Diffstat (limited to 'drivers/gpu/drm/nouveau/nvkm/subdev/clk/pllnv04.c')
| -rw-r--r-- | drivers/gpu/drm/nouveau/nvkm/subdev/clk/pllnv04.c | 245 |
1 files changed, 245 insertions, 0 deletions
diff --git a/drivers/gpu/drm/nouveau/nvkm/subdev/clk/pllnv04.c b/drivers/gpu/drm/nouveau/nvkm/subdev/clk/pllnv04.c new file mode 100644 index 000000000000..f2292895a1a8 --- /dev/null +++ b/drivers/gpu/drm/nouveau/nvkm/subdev/clk/pllnv04.c @@ -0,0 +1,245 @@ +/* + * Copyright 1993-2003 NVIDIA, Corporation + * Copyright 2007-2009 Stuart Bennett + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, + * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF + * OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + */ +#include "pll.h" + +#include <subdev/bios.h> +#include <subdev/bios/pll.h> + +static int +getMNP_single(struct nvkm_subdev *subdev, struct nvbios_pll *info, int clk, + int *pN, int *pM, int *pP) +{ + /* Find M, N and P for a single stage PLL + * + * Note that some bioses (NV3x) have lookup tables of precomputed MNP + * values, but we're too lazy to use those atm + * + * "clk" parameter in kHz + * returns calculated clock + */ + struct nvkm_bios *bios = nvkm_bios(subdev); + int minvco = info->vco1.min_freq, maxvco = info->vco1.max_freq; + int minM = info->vco1.min_m, maxM = info->vco1.max_m; + int minN = info->vco1.min_n, maxN = info->vco1.max_n; + int minU = info->vco1.min_inputfreq; + int maxU = info->vco1.max_inputfreq; + int minP = info->min_p; + int maxP = info->max_p_usable; + int crystal = info->refclk; + int M, N, thisP, P; + int clkP, calcclk; + int delta, bestdelta = INT_MAX; + int bestclk = 0; + + /* this division verified for nv20, nv18, nv28 (Haiku), and nv34 */ + /* possibly correlated with introduction of 27MHz crystal */ + if (bios->version.major < 0x60) { + int cv = bios->version.chip; + if (cv < 0x17 || cv == 0x1a || cv == 0x20) { + if (clk > 250000) + maxM = 6; + if (clk > 340000) + maxM = 2; + } else if (cv < 0x40) { + if (clk > 150000) + maxM = 6; + if (clk > 200000) + maxM = 4; + if (clk > 340000) + maxM = 2; + } + } + + P = 1 << maxP; + if ((clk * P) < minvco) { + minvco = clk * maxP; + maxvco = minvco * 2; + } + + if (clk + clk/200 > maxvco) /* +0.5% */ + maxvco = clk + clk/200; + + /* NV34 goes maxlog2P->0, NV20 goes 0->maxlog2P */ + for (thisP = minP; thisP <= maxP; thisP++) { + P = 1 << thisP; + clkP = clk * P; + + if (clkP < minvco) + continue; + if (clkP > maxvco) + return bestclk; + + for (M = minM; M <= maxM; M++) { + if (crystal/M < minU) + return bestclk; + if (crystal/M > maxU) + continue; + + /* add crystal/2 to round better */ + N = (clkP * M + crystal/2) / crystal; + + if (N < minN) + continue; + if (N > maxN) + break; + + /* more rounding additions */ + calcclk = ((N * crystal + P/2) / P + M/2) / M; + delta = abs(calcclk - clk); + /* we do an exhaustive search rather than terminating + * on an optimality condition... + */ + if (delta < bestdelta) { + bestdelta = delta; + bestclk = calcclk; + *pN = N; + *pM = M; + *pP = thisP; + if (delta == 0) /* except this one */ + return bestclk; + } + } + } + + return bestclk; +} + +static int +getMNP_double(struct nvkm_subdev *subdev, struct nvbios_pll *info, int clk, + int *pN1, int *pM1, int *pN2, int *pM2, int *pP) +{ + /* Find M, N and P for a two stage PLL + * + * Note that some bioses (NV30+) have lookup tables of precomputed MNP + * values, but we're too lazy to use those atm + * + * "clk" parameter in kHz + * returns calculated clock + */ + int chip_version = nvkm_bios(subdev)->version.chip; + int minvco1 = info->vco1.min_freq, maxvco1 = info->vco1.max_freq; + int minvco2 = info->vco2.min_freq, maxvco2 = info->vco2.max_freq; + int minU1 = info->vco1.min_inputfreq, minU2 = info->vco2.min_inputfreq; + int maxU1 = info->vco1.max_inputfreq, maxU2 = info->vco2.max_inputfreq; + int minM1 = info->vco1.min_m, maxM1 = info->vco1.max_m; + int minN1 = info->vco1.min_n, maxN1 = info->vco1.max_n; + int minM2 = info->vco2.min_m, maxM2 = info->vco2.max_m; + int minN2 = info->vco2.min_n, maxN2 = info->vco2.max_n; + int maxlog2P = info->max_p_usable; + int crystal = info->refclk; + bool fixedgain2 = (minM2 == maxM2 && minN2 == maxN2); + int M1, N1, M2, N2, log2P; + int clkP, calcclk1, calcclk2, calcclkout; + int delta, bestdelta = INT_MAX; + int bestclk = 0; + + int vco2 = (maxvco2 - maxvco2/200) / 2; + for (log2P = 0; clk && log2P < maxlog2P && clk <= (vco2 >> log2P); log2P++) + ; + clkP = clk << log2P; + + if (maxvco2 < clk + clk/200) /* +0.5% */ + maxvco2 = clk + clk/200; + + for (M1 = minM1; M1 <= maxM1; M1++) { + if (crystal/M1 < minU1) + return bestclk; + if (crystal/M1 > maxU1) + continue; + + for (N1 = minN1; N1 <= maxN1; N1++) { + calcclk1 = crystal * N1 / M1; + if (calcclk1 < minvco1) + continue; + if (calcclk1 > maxvco1) + break; + + for (M2 = minM2; M2 <= maxM2; M2++) { + if (calcclk1/M2 < minU2) + break; + if (calcclk1/M2 > maxU2) + continue; + + /* add calcclk1/2 to round better */ + N2 = (clkP * M2 + calcclk1/2) / calcclk1; + if (N2 < minN2) + continue; + if (N2 > maxN2) + break; + + if (!fixedgain2) { + if (chip_version < 0x60) + if (N2/M2 < 4 || N2/M2 > 10) + continue; + + calcclk2 = calcclk1 * N2 / M2; + if (calcclk2 < minvco2) + break; + if (calcclk2 > maxvco2) + continue; + } else + calcclk2 = calcclk1; + + calcclkout = calcclk2 >> log2P; + delta = abs(calcclkout - clk); + /* we do an exhaustive search rather than terminating + * on an optimality condition... + */ + if (delta < bestdelta) { + bestdelta = delta; + bestclk = calcclkout; + *pN1 = N1; + *pM1 = M1; + *pN2 = N2; + *pM2 = M2; + *pP = log2P; + if (delta == 0) /* except this one */ + return bestclk; + } + } + } + } + + return bestclk; +} + +int +nv04_pll_calc(struct nvkm_subdev *subdev, struct nvbios_pll *info, u32 freq, + int *N1, int *M1, int *N2, int *M2, int *P) +{ + int ret; + + if (!info->vco2.max_freq || !N2) { + ret = getMNP_single(subdev, info, freq, N1, M1, P); + if (N2) { + *N2 = 1; + *M2 = 1; + } + } else { + ret = getMNP_double(subdev, info, freq, N1, M1, N2, M2, P); + } + + if (!ret) + nv_error(subdev, "unable to compute acceptable pll values\n"); + return ret; +} |