1 /*
2 * PowerQUICC II support functions
3 *
4 * Author: Scott Wood <scottwood@freescale.com>
5 *
6 * Copyright (c) 2007 Freescale Semiconductor, Inc.
7 *
8 * This program is free software; you can redistribute it and/or modify it
9 * under the terms of the GNU General Public License version 2 as published
10 * by the Free Software Foundation.
11 */
12
13 #include "ops.h"
14 #include "types.h"
15 #include "fsl-soc.h"
16 #include "pq2.h"
17 #include "stdio.h"
18 #include "io.h"
19
20 #define PQ2_SCCR (0x10c80/4) /* System Clock Configuration Register */
21 #define PQ2_SCMR (0x10c88/4) /* System Clock Mode Register */
22
23 static int pq2_corecnf_map[] = {
24 3, 2, 2, 2, 4, 4, 5, 9, 6, 11, 8, 10, 3, 12, 7, -1,
25 6, 5, 13, 2, 14, 4, 15, 9, 0, 11, 8, 10, 16, 12, 7, -1
26 };
27
28 /* Get various clocks from crystal frequency.
29 * Returns zero on failure and non-zero on success.
30 */
pq2_get_clocks(u32 crystal,u32 * sysfreq,u32 * corefreq,u32 * timebase,u32 * brgfreq)31 int pq2_get_clocks(u32 crystal, u32 *sysfreq, u32 *corefreq,
32 u32 *timebase, u32 *brgfreq)
33 {
34 u32 *immr;
35 u32 sccr, scmr, mainclk, busclk;
36 int corecnf, busdf, plldf, pllmf, dfbrg;
37
38 immr = fsl_get_immr();
39 if (!immr) {
40 printf("pq2_get_clocks: Couldn't get IMMR base.\r\n");
41 return 0;
42 }
43
44 sccr = in_be32(&immr[PQ2_SCCR]);
45 scmr = in_be32(&immr[PQ2_SCMR]);
46
47 dfbrg = sccr & 3;
48 corecnf = (scmr >> 24) & 0x1f;
49 busdf = (scmr >> 20) & 0xf;
50 plldf = (scmr >> 12) & 1;
51 pllmf = scmr & 0xfff;
52
53 mainclk = crystal * (pllmf + 1) / (plldf + 1);
54 busclk = mainclk / (busdf + 1);
55
56 if (sysfreq)
57 *sysfreq = mainclk / 2;
58 if (timebase)
59 *timebase = busclk / 4;
60 if (brgfreq)
61 *brgfreq = mainclk / (1 << ((dfbrg + 1) * 2));
62
63 if (corefreq) {
64 int coremult = pq2_corecnf_map[corecnf];
65
66 if (coremult < 0)
67 *corefreq = mainclk / 2;
68 else if (coremult == 0)
69 return 0;
70 else
71 *corefreq = busclk * coremult / 2;
72 }
73
74 return 1;
75 }
76
77 /* Set common device tree fields based on the given clock frequencies. */
pq2_set_clocks(u32 sysfreq,u32 corefreq,u32 timebase,u32 brgfreq)78 void pq2_set_clocks(u32 sysfreq, u32 corefreq, u32 timebase, u32 brgfreq)
79 {
80 void *node;
81
82 dt_fixup_cpu_clocks(corefreq, timebase, sysfreq);
83
84 node = finddevice("/soc/cpm");
85 if (node)
86 setprop(node, "clock-frequency", &sysfreq, 4);
87
88 node = finddevice("/soc/cpm/brg");
89 if (node)
90 setprop(node, "clock-frequency", &brgfreq, 4);
91 }
92
pq2_fixup_clocks(u32 crystal)93 int pq2_fixup_clocks(u32 crystal)
94 {
95 u32 sysfreq, corefreq, timebase, brgfreq;
96
97 if (!pq2_get_clocks(crystal, &sysfreq, &corefreq, &timebase, &brgfreq))
98 return 0;
99
100 pq2_set_clocks(sysfreq, corefreq, timebase, brgfreq);
101 return 1;
102 }
103