diff options
Diffstat (limited to 'drivers/gpu/drm/nouveau/nv50_calc.c')
-rw-r--r-- | drivers/gpu/drm/nouveau/nv50_calc.c | 97 |
1 files changed, 97 insertions, 0 deletions
diff --git a/drivers/gpu/drm/nouveau/nv50_calc.c b/drivers/gpu/drm/nouveau/nv50_calc.c new file mode 100644 index 00000000..8cf63a8b --- /dev/null +++ b/drivers/gpu/drm/nouveau/nv50_calc.c @@ -0,0 +1,97 @@ +/* + * Copyright 2010 Red Hat Inc. + * + * 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 COPYRIGHT HOLDER(S) OR AUTHOR(S) 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. + * + * Authors: Ben Skeggs + */ + +#include "drmP.h" +#include "nouveau_drv.h" +#include "nouveau_hw.h" + +int +nv50_calc_pll(struct drm_device *dev, struct pll_lims *pll, int clk, + int *N1, int *M1, int *N2, int *M2, int *P) +{ + struct nouveau_pll_vals pll_vals; + int ret; + + ret = nouveau_calc_pll_mnp(dev, pll, clk, &pll_vals); + if (ret <= 0) + return ret; + + *N1 = pll_vals.N1; + *M1 = pll_vals.M1; + *N2 = pll_vals.N2; + *M2 = pll_vals.M2; + *P = pll_vals.log2P; + return ret; +} + +int +nva3_calc_pll(struct drm_device *dev, struct pll_lims *pll, int clk, + int *pN, int *pfN, int *pM, int *P) +{ + u32 best_err = ~0, err; + int M, lM, hM, N, fN; + + *P = pll->vco1.maxfreq / clk; + if (*P > pll->max_p) + *P = pll->max_p; + if (*P < pll->min_p) + *P = pll->min_p; + + lM = (pll->refclk + pll->vco1.max_inputfreq) / pll->vco1.max_inputfreq; + lM = max(lM, (int)pll->vco1.min_m); + hM = (pll->refclk + pll->vco1.min_inputfreq) / pll->vco1.min_inputfreq; + hM = min(hM, (int)pll->vco1.max_m); + + for (M = lM; M <= hM; M++) { + u32 tmp = clk * *P * M; + N = tmp / pll->refclk; + fN = tmp % pll->refclk; + if (!pfN && fN >= pll->refclk / 2) + N++; + + if (N < pll->vco1.min_n) + continue; + if (N > pll->vco1.max_n) + break; + + err = abs(clk - (pll->refclk * N / M / *P)); + if (err < best_err) { + best_err = err; + *pN = N; + *pM = M; + } + + if (pfN) { + *pfN = (((fN << 13) / pll->refclk) - 4096) & 0xffff; + return clk; + } + } + + if (unlikely(best_err == ~0)) { + NV_ERROR(dev, "unable to find matching pll values\n"); + return -EINVAL; + } + + return pll->refclk * *pN / *pM / *P; +} |