1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * Copyright 2010-2011 Freescale Semiconductor, Inc.
4 */
5
6 #include <common.h>
7 #include <log.h>
8 #include <asm/io.h>
9
10 #include "ics307_clk.h"
11
12 #if defined(CONFIG_FSL_NGPIXIS)
13 #include "ngpixis.h"
14 #define fpga_reg pixis
15 #elif defined(CONFIG_FSL_QIXIS)
16 #include "qixis.h"
17 #define fpga_reg ((struct qixis *)QIXIS_BASE)
18 #else
19 #include "pixis.h"
20 #define fpga_reg pixis
21 #endif
22
23 /* define for SYS CLK or CLK1Frequency */
24 #define TTL 1
25 #define CLK2 0
26 #define CRYSTAL 0
27 #define MAX_VDW (511 + 8)
28 #define MAX_RDW (127 + 2)
29 #define MIN_VDW (4 + 8)
30 #define MIN_RDW (1 + 2)
31 #define NUM_OD_SETTING 8
32 /*
33 * These defines cover the industrial temperature range part,
34 * for commercial, change below to 400000 and 55000, respectively
35 */
36 #define MAX_VCO 360000
37 #define MIN_VCO 60000
38
39 /* decode S[0-2] to Output Divider (OD) */
40 static u8 ics307_s_to_od[] = {
41 10, 2, 8, 4, 5, 7, 3, 6
42 };
43
44 /*
45 * Find one solution to generate required frequency for SYSCLK
46 * out_freq: KHz, required frequency to the SYSCLK
47 * the result will be retuned with component RDW, VDW, OD, TTL,
48 * CLK2 and crystal
49 */
ics307_sysclk_calculator(unsigned long out_freq)50 unsigned long ics307_sysclk_calculator(unsigned long out_freq)
51 {
52 const unsigned long input_freq = CONFIG_ICS307_REFCLK_HZ;
53 unsigned long vdw, rdw, odp, s_vdw = 0, s_rdw = 0, s_odp = 0, od;
54 unsigned long tmp_out, diff, result = 0;
55 int found = 0;
56
57 for (odp = 0; odp < NUM_OD_SETTING; odp++) {
58 od = ics307_s_to_od[odp];
59 if (od * out_freq < MIN_VCO || od * out_freq > MAX_VCO)
60 continue;
61 for (rdw = MIN_RDW; rdw <= MAX_RDW; rdw++) {
62 /* Calculate the VDW */
63 vdw = out_freq * 1000 * od * rdw / (input_freq * 2);
64 if (vdw > MAX_VDW)
65 vdw = MAX_VDW;
66 if (vdw < MIN_VDW)
67 continue;
68 /* Calculate the temp out frequency */
69 tmp_out = input_freq * 2 * vdw / (rdw * od * 1000);
70 diff = max(out_freq, tmp_out) - min(out_freq, tmp_out);
71 /*
72 * calculate the percent, the precision is 1/1000
73 * If greater than 1/1000, continue
74 * otherwise, we think the solution is we required
75 */
76 if (diff * 1000 / out_freq > 1)
77 continue;
78 else {
79 s_vdw = vdw;
80 s_rdw = rdw;
81 s_odp = odp;
82 found = 1;
83 break;
84 }
85 }
86 }
87
88 if (found)
89 result = (s_rdw - 2) | (s_vdw - 8) << 7 | s_odp << 16 |
90 CLK2 << 19 | TTL << 21 | CRYSTAL << 22;
91
92 debug("ICS307-02: RDW: %ld, VDW: %ld, OD: %d\n", s_rdw - 2, s_vdw - 8,
93 ics307_s_to_od[s_odp]);
94 return result;
95 }
96
97 /*
98 * Calculate frequency being generated by ICS307-02 clock chip based upon
99 * the control bytes being programmed into it.
100 */
ics307_clk_freq(u8 cw0,u8 cw1,u8 cw2)101 static unsigned long ics307_clk_freq(u8 cw0, u8 cw1, u8 cw2)
102 {
103 const unsigned long input_freq = CONFIG_ICS307_REFCLK_HZ;
104 unsigned long vdw = ((cw1 << 1) & 0x1FE) + ((cw2 >> 7) & 1);
105 unsigned long rdw = cw2 & 0x7F;
106 unsigned long od = ics307_s_to_od[cw0 & 0x7];
107 unsigned long freq;
108
109 /*
110 * CLK1 Freq = Input Frequency * 2 * (VDW + 8) / ((RDW + 2) * OD)
111 *
112 * cw0: C1 C0 TTL F1 F0 S2 S1 S0
113 * cw1: V8 V7 V6 V5 V4 V3 V2 V1
114 * cw2: V0 R6 R5 R4 R3 R2 R1 R0
115 *
116 * R6:R0 = Reference Divider Word (RDW)
117 * V8:V0 = VCO Divider Word (VDW)
118 * S2:S0 = Output Divider Select (OD)
119 * F1:F0 = Function of CLK2 Output
120 * TTL = duty cycle
121 * C1:C0 = internal load capacitance for cyrstal
122 *
123 */
124
125 freq = input_freq * 2 * (vdw + 8) / ((rdw + 2) * od);
126
127 debug("ICS307: CW[0-2]: %02X %02X %02X => %lu Hz\n", cw0, cw1, cw2,
128 freq);
129 return freq;
130 }
131
get_board_sys_clk(void)132 unsigned long get_board_sys_clk(void)
133 {
134 return ics307_clk_freq(
135 in_8(&fpga_reg->sclk[0]),
136 in_8(&fpga_reg->sclk[1]),
137 in_8(&fpga_reg->sclk[2]));
138 }
139
get_board_ddr_clk(void)140 unsigned long get_board_ddr_clk(void)
141 {
142 return ics307_clk_freq(
143 in_8(&fpga_reg->dclk[0]),
144 in_8(&fpga_reg->dclk[1]),
145 in_8(&fpga_reg->dclk[2]));
146 }
147