1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Joshua Henderson <joshua.henderson@microchip.com>
4 * Copyright (C) 2015 Microchip Technology Inc. All rights reserved.
5 */
6 #include <asm/mach-pic32/pic32.h>
7
8 #include "pic32mzda.h"
9
10 /* Oscillators, PLL & clocks */
11 #define ICLK_MASK 0x00000080
12 #define PLLDIV_MASK 0x00000007
13 #define CUROSC_MASK 0x00000007
14 #define PLLMUL_MASK 0x0000007F
15 #define PB_MASK 0x00000007
16 #define FRC1 0
17 #define FRC2 7
18 #define SPLL 1
19 #define POSC 2
20 #define FRC_CLK 8000000
21
22 #define PIC32_POSC_FREQ 24000000
23
24 #define OSCCON 0x0000
25 #define SPLLCON 0x0020
26 #define PB1DIV 0x0140
27
28 u32 pic32_get_sysclk(void)
29 {
30 u32 osc_freq = 0;
31 u32 pllclk;
32 u32 frcdivn;
33 u32 osccon;
34 u32 spllcon;
35 int curr_osc;
36
37 u32 plliclk;
38 u32 pllidiv;
39 u32 pllodiv;
40 u32 pllmult;
41 u32 frcdiv;
42
43 void __iomem *osc_base = ioremap(PIC32_BASE_OSC, 0x200);
44
45 osccon = __raw_readl(osc_base + OSCCON);
46 spllcon = __raw_readl(osc_base + SPLLCON);
47
48 plliclk = (spllcon & ICLK_MASK);
49 pllidiv = ((spllcon >> 8) & PLLDIV_MASK) + 1;
50 pllodiv = ((spllcon >> 24) & PLLDIV_MASK);
51 pllmult = ((spllcon >> 16) & PLLMUL_MASK) + 1;
52 frcdiv = ((osccon >> 24) & PLLDIV_MASK);
53
54 pllclk = plliclk ? FRC_CLK : PIC32_POSC_FREQ;
55 frcdivn = ((1 << frcdiv) + 1) + (128 * (frcdiv == 7));
56
57 if (pllodiv < 2)
58 pllodiv = 2;
59 else if (pllodiv < 5)
60 pllodiv = (1 << pllodiv);
61 else
62 pllodiv = 32;
63
64 curr_osc = (int)((osccon >> 12) & CUROSC_MASK);
65
66 switch (curr_osc) {
67 case FRC1:
68 case FRC2:
69 osc_freq = FRC_CLK / frcdivn;
70 break;
71 case SPLL:
72 osc_freq = ((pllclk / pllidiv) * pllmult) / pllodiv;
73 break;
74 case POSC:
75 osc_freq = PIC32_POSC_FREQ;
76 break;
77 default:
78 break;
79 }
80
81 iounmap(osc_base);
82
83 return osc_freq;
84 }
85
86 u32 pic32_get_pbclk(int bus)
87 {
88 u32 clk_freq;
89 void __iomem *osc_base = ioremap(PIC32_BASE_OSC, 0x200);
90 u32 pbxdiv = PB1DIV + ((bus - 1) * 0x10);
91 u32 pbdiv = (__raw_readl(osc_base + pbxdiv) & PB_MASK) + 1;
92
93 iounmap(osc_base);
94
95 clk_freq = pic32_get_sysclk();
96
97 return clk_freq / pbdiv;
98 }
99
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