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26 #include <subdev/bios.h>
27 #include <subdev/bios/pll.h>
30 gt215_pll_calc(struct nvkm_subdev *subdev, struct nvbios_pll *info,
31 u32 freq, int *pN, int *pfN, int *pM, int *P)
33 u32 best_err = ~0, err;
36 *P = info->vco1.max_freq / freq;
42 lM = (info->refclk + info->vco1.max_inputfreq) / info->vco1.max_inputfreq;
43 lM = max(lM, (int)info->vco1.min_m);
44 hM = (info->refclk + info->vco1.min_inputfreq) / info->vco1.min_inputfreq;
45 hM = min(hM, (int)info->vco1.max_m);
48 for (M = lM; M <= hM; M++) {
49 u32 tmp = freq * *P * M;
50 N = tmp / info->refclk;
51 fN = tmp % info->refclk;
54 if (fN >= info->refclk / 2)
57 if (fN < info->refclk / 2)
59 fN = tmp - (N * info->refclk);
62 if (N < info->vco1.min_n)
64 if (N > info->vco1.max_n)
67 err = abs(freq - (info->refclk * N / M / *P));
75 *pfN = ((fN << 13) + info->refclk / 2) / info->refclk;
76 *pfN = (*pfN - 4096) & 0xffff;
81 if (unlikely(best_err == ~0)) {
82 nvkm_error(subdev, "unable to find matching pll values\n");
86 return info->refclk * *pN / *pM / *P;