diff options
Diffstat (limited to 'arch/powerpc/boot/pq2.c')
-rw-r--r-- | arch/powerpc/boot/pq2.c | 102 |
1 files changed, 102 insertions, 0 deletions
diff --git a/arch/powerpc/boot/pq2.c b/arch/powerpc/boot/pq2.c new file mode 100644 index 000000000000..f6d118558f1d --- /dev/null +++ b/arch/powerpc/boot/pq2.c | |||
@@ -0,0 +1,102 @@ | |||
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 | */ | ||
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. */ | ||
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 | |||
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 | } | ||