aboutsummaryrefslogtreecommitdiffstats
path: root/arch/powerpc/boot/pq2.c
diff options
context:
space:
mode:
authorScott Wood <scottwood@freescale.com>2007-08-27 14:46:38 -0400
committerKumar Gala <galak@kernel.crashing.org>2007-10-03 21:36:35 -0400
commitbbc6fac387f09e46a372e4aadbc935cba5a6b463 (patch)
tree930a30665c87ad0bd3c845ba892817f4a7b0ba19 /arch/powerpc/boot/pq2.c
parent568091512d464b06f17b88bfd2bdc1ec98a697bd (diff)
[POWERPC] bootwrapper: Add fsl_get_immr() and 8xx/pq2 clock functions.
fsl_get_immr() uses /soc/ranges to determine the immr. mpc885_get_clock() transforms a crystal frequency into a system frequency according to the PLL register settings. pq2_get_clocks() does the same as the above for the PowerQUICC II, except that it produces several different clocks. The mpc8xx/pq2 set_clocks() functions modify common properties in the device tree based on the given clock data. The mpc885/pq2 fixup_clocks() functions call get_clocks(), and pass the results to set_clocks(). Signed-off-by: Scott Wood <scottwood@freescale.com> Acked-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Diffstat (limited to 'arch/powerpc/boot/pq2.c')
-rw-r--r--arch/powerpc/boot/pq2.c102
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
23static 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 */
31int 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. */
78void 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
93int 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}