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-rw-r--r--tools/mpc86x_clk.c218
1 files changed, 218 insertions, 0 deletions
diff --git a/tools/mpc86x_clk.c b/tools/mpc86x_clk.c
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+++ b/tools/mpc86x_clk.c
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+/*
+ * (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;
+}