1*d2912cb1SThomas Gleixner // SPDX-License-Identifier: GPL-2.0-only
2bbc6fac3SScott Wood /*
3bbc6fac3SScott Wood * MPC8xx support functions
4bbc6fac3SScott Wood *
5bbc6fac3SScott Wood * Author: Scott Wood <scottwood@freescale.com>
6bbc6fac3SScott Wood *
7bbc6fac3SScott Wood * Copyright (c) 2007 Freescale Semiconductor, Inc.
8bbc6fac3SScott Wood */
9bbc6fac3SScott Wood
10bbc6fac3SScott Wood #include "ops.h"
11bbc6fac3SScott Wood #include "types.h"
12bbc6fac3SScott Wood #include "fsl-soc.h"
13bbc6fac3SScott Wood #include "mpc8xx.h"
14bbc6fac3SScott Wood #include "stdio.h"
15bbc6fac3SScott Wood #include "io.h"
16bbc6fac3SScott Wood
17bbc6fac3SScott Wood #define MPC8XX_PLPRCR (0x284/4) /* PLL and Reset Control Register */
18bbc6fac3SScott Wood
19bbc6fac3SScott Wood /* Return system clock from crystal frequency */
mpc885_get_clock(u32 crystal)20bbc6fac3SScott Wood u32 mpc885_get_clock(u32 crystal)
21bbc6fac3SScott Wood {
22bbc6fac3SScott Wood u32 *immr;
23bbc6fac3SScott Wood u32 plprcr;
24169f438aSChristophe Leroy int mfi, mfn, mfd, pdf;
25bbc6fac3SScott Wood u32 ret;
26bbc6fac3SScott Wood
27bbc6fac3SScott Wood immr = fsl_get_immr();
28bbc6fac3SScott Wood if (!immr) {
29bbc6fac3SScott Wood printf("mpc885_get_clock: Couldn't get IMMR base.\r\n");
30bbc6fac3SScott Wood return 0;
31bbc6fac3SScott Wood }
32bbc6fac3SScott Wood
33bbc6fac3SScott Wood plprcr = in_be32(&immr[MPC8XX_PLPRCR]);
34bbc6fac3SScott Wood
35bbc6fac3SScott Wood mfi = (plprcr >> 16) & 15;
36bbc6fac3SScott Wood if (mfi < 5) {
37bbc6fac3SScott Wood printf("Warning: PLPRCR[MFI] value of %d out-of-bounds\r\n",
38bbc6fac3SScott Wood mfi);
39bbc6fac3SScott Wood mfi = 5;
40bbc6fac3SScott Wood }
41bbc6fac3SScott Wood
42bbc6fac3SScott Wood pdf = (plprcr >> 1) & 0xf;
43bbc6fac3SScott Wood mfd = (plprcr >> 22) & 0x1f;
44bbc6fac3SScott Wood mfn = (plprcr >> 27) & 0x1f;
45bbc6fac3SScott Wood
46bbc6fac3SScott Wood ret = crystal * mfi;
47bbc6fac3SScott Wood
48bbc6fac3SScott Wood if (mfn != 0)
49bbc6fac3SScott Wood ret += crystal * mfn / (mfd + 1);
50bbc6fac3SScott Wood
51bbc6fac3SScott Wood return ret / (pdf + 1);
52bbc6fac3SScott Wood }
53bbc6fac3SScott Wood
54bbc6fac3SScott Wood /* Set common device tree fields based on the given clock frequencies. */
mpc8xx_set_clocks(u32 sysclk)55bbc6fac3SScott Wood void mpc8xx_set_clocks(u32 sysclk)
56bbc6fac3SScott Wood {
57bbc6fac3SScott Wood void *node;
58bbc6fac3SScott Wood
59bbc6fac3SScott Wood dt_fixup_cpu_clocks(sysclk, sysclk / 16, sysclk);
60bbc6fac3SScott Wood
61bbc6fac3SScott Wood node = finddevice("/soc/cpm");
62bbc6fac3SScott Wood if (node)
63bbc6fac3SScott Wood setprop(node, "clock-frequency", &sysclk, 4);
64bbc6fac3SScott Wood
65bbc6fac3SScott Wood node = finddevice("/soc/cpm/brg");
66bbc6fac3SScott Wood if (node)
67bbc6fac3SScott Wood setprop(node, "clock-frequency", &sysclk, 4);
68bbc6fac3SScott Wood }
69bbc6fac3SScott Wood
mpc885_fixup_clocks(u32 crystal)70bbc6fac3SScott Wood int mpc885_fixup_clocks(u32 crystal)
71bbc6fac3SScott Wood {
72bbc6fac3SScott Wood u32 sysclk = mpc885_get_clock(crystal);
73bbc6fac3SScott Wood if (!sysclk)
74bbc6fac3SScott Wood return 0;
75bbc6fac3SScott Wood
76bbc6fac3SScott Wood mpc8xx_set_clocks(sysclk);
77bbc6fac3SScott Wood return 1;
78bbc6fac3SScott Wood }
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