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Diffstat (limited to 'tools/mpc86x_clk.c')
| -rw-r--r-- | tools/mpc86x_clk.c | 218 |
1 files changed, 218 insertions, 0 deletions
diff --git a/tools/mpc86x_clk.c b/tools/mpc86x_clk.c new file mode 100644 index 0000000..8dfbd4e --- /dev/null +++ b/tools/mpc86x_clk.c @@ -0,0 +1,218 @@ +/* + * (C) Copyright 2003 Intracom S.A. + * Pantelis Antoniou <panto@intracom.gr> + * + * This little program makes an exhaustive search for the + * correct terms of pdf, mfi, mfn, mfd, s, dbrmo, in PLPRCR. + * The goal is to produce a gclk2 from a xin input, while respecting + * all the restrictions on their combination. + * + * Generaly you select the first row of the produced table. + * + * See file CREDITS for list of people who contributed to this + * project. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation; either version 2 of + * the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, + * MA 02111-1307 USA + */ + + +#include <stdio.h> +#include <stdlib.h> + +#define DPREF_MIN 10000000 +#define DPREF_MAX 32000000 + +#define DPGDCK_MAX 320000000 +#define DPGDCK_MIN 160000000 + +#define S_MIN 0 +#define S_MAX 2 + +#define MFI_MIN 5 +#define MFI_MAX 15 + +#define MFN_MIN 0 +#define MFN_MAX 15 + +#define MFD_MIN 0 +#define MFD_MAX 31 + +#define MF_MIN 5 +#define MF_MAX 15 + +#define PDF_MIN 0 +#define PDF_MAX 15 + +#define GCLK2_MAX 150000000 + +static int calculate (int xin, int target_clock, + int ppm, int pdf, int mfi, int mfn, int mfd, int s, + int *dprefp, int *dpgdckp, int *jdbckp, + int *gclk2p, int *dbrmop) +{ + unsigned int dpref, dpgdck, jdbck, gclk2, t1, t2, dbrmo; + + /* valid MFI? */ + if (mfi < MFI_MIN) + return -1; + + /* valid num, denum? */ + if (mfn > 0 && mfn >= mfd) + return -1; + + dpref = xin / (pdf + 1); + + /* valid dpef? */ + if (dpref < DPREF_MIN || dpref > DPREF_MAX) + return -1; + + if (mfn == 0) { + dpgdck = (2 * mfi * xin) / (pdf + 1) ; + dbrmo = 0; + } else { + /* 5 <= mfi + (mfn / mfd + 1) <= 15 */ + t1 = mfd + 1; + t2 = mfi * t1 + mfn; + if ( MF_MIN * t1 > t2 || MF_MAX * t1 < t2) + return -1; + + dpgdck = (unsigned int)(2 * (mfi * mfd + mfi + mfn) * + (unsigned int)xin) / + ((mfd + 1) * (pdf + 1)); + + dbrmo = 10 * mfn < (mfd + 1); + } + + /* valid dpgclk? */ + if (dpgdck < DPGDCK_MIN || dpgdck > DPGDCK_MAX) + return -1; + + jdbck = dpgdck >> s; + gclk2 = jdbck / 2; + + /* valid gclk2 */ + if (gclk2 > GCLK2_MAX) + return -1; + + t1 = abs(gclk2 - target_clock); + + /* XXX max 1MHz dev. in clock */ + if (t1 > 1000000) + return -1; + + /* dev within range (XXX gclk2 scaled to avoid overflow) */ + if (t1 * 1000 > (unsigned int)ppm * (gclk2 / 1000)) + return -1; + + *dprefp = dpref; + *dpgdckp = dpgdck; + *jdbckp = jdbck; + *gclk2p = gclk2; + *dbrmop = dbrmo; + + return gclk2; +} + +int conf_clock(int xin, int target_clock, int ppm) +{ + int pdf, s, mfn, mfd, mfi; + int dpref, dpgdck, jdbck, gclk2, xout, dbrmo; + int found = 0; + + /* integer multipliers */ + for (pdf = PDF_MIN; pdf <= PDF_MAX; pdf++) { + for (mfi = MFI_MIN; mfi <= MFI_MAX; mfi++) { + for (s = 0; s <= S_MAX; s++) { + xout = calculate(xin, target_clock, + ppm, pdf, mfi, 0, 0, s, + &dpref, &dpgdck, &jdbck, + &gclk2, &dbrmo); + if (xout < 0) + continue; + + if (found == 0) { + printf("pdf mfi mfn mfd s dbrmo dpref dpgdck jdbck gclk2 exact?\n"); + printf("--- --- --- --- - ----- ----- ------ ----- ----- ------\n"); + } + + printf("%3d %3d --- --- %1d %5d %9d %9d %9d %9d%s\n", + pdf, mfi, s, dbrmo, + dpref, dpgdck, jdbck, gclk2, + gclk2 == target_clock ? " YES" : ""); + + found++; + } + } + } + + /* fractional multipliers */ + for (pdf = PDF_MIN; pdf <= PDF_MAX; pdf++) { + for (mfi = MFI_MIN; mfi <= MFI_MAX; mfi++) { + for (mfn = 1; mfn <= MFN_MAX; mfn++) { + for (mfd = 1; mfd <= MFD_MAX; mfd++) { + for (s = 0; s <= S_MAX; s++) { + xout = calculate(xin, target_clock, + ppm, pdf, mfi, mfn, mfd, s, + &dpref, &dpgdck, &jdbck, + &gclk2, &dbrmo); + if (xout < 0) + continue; + + if (found == 0) { + printf("pdf mfi mfn mfd s dbrmo dpref dpgdck jdbck gclk2 exact?\n"); + printf("--- --- --- --- - ----- ----- ------ ----- ----- ------\n"); + } + + printf("%3d %3d %3d %3d %1d %5d %9d %9d %9d %9d%s\n", + pdf, mfi, mfn, mfd, s, + dbrmo, dpref, dpgdck, jdbck, gclk2, + gclk2 == target_clock ? " YES" : ""); + + found++; + } + } + } + + } + } + + return found; +} + +int main(int argc, char *argv[]) +{ + int xin, want_gclk2, found, ppm = 100; + + if (argc < 3) { + fprintf(stderr, "usage: mpc86x_clk <xin> <want_gclk2> [ppm]\n"); + fprintf(stderr, " default ppm is 100\n"); + return 10; + } + + xin = atoi(argv[1]); + want_gclk2 = atoi(argv[2]); + if (argc >= 4) + ppm = atoi(argv[3]); + + found = conf_clock(xin, want_gclk2, ppm); + if (found <= 0) { + fprintf(stderr, "cannot produce gclk2 %d from xin %d\n", + want_gclk2, xin); + return EXIT_FAILURE; + } + + return EXIT_SUCCESS; +} |