]>
Commit | Line | Data |
---|---|---|
1 | /* | |
2 | * | |
3 | * (C) Copyright 2000-2003 | |
4 | * Wolfgang Denk, DENX Software Engineering, wd@denx.de. | |
5 | * | |
6 | * Copyright (C) 2004-2008, 2012 Freescale Semiconductor, Inc. | |
7 | * TsiChung Liew (Tsi-Chung.Liew@freescale.com) | |
8 | * | |
9 | * See file CREDITS for list of people who contributed to this | |
10 | * project. | |
11 | * | |
12 | * This program is free software; you can redistribute it and/or | |
13 | * modify it under the terms of the GNU General Public License as | |
14 | * published by the Free Software Foundation; either version 2 of | |
15 | * the License, or (at your option) any later version. | |
16 | * | |
17 | * This program is distributed in the hope that it will be useful, | |
18 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
19 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
20 | * GNU General Public License for more details. | |
21 | * | |
22 | * You should have received a copy of the GNU General Public License | |
23 | * along with this program; if not, write to the Free Software | |
24 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, | |
25 | * MA 02111-1307 USA | |
26 | */ | |
27 | ||
28 | #include <common.h> | |
29 | #include <asm/processor.h> | |
30 | ||
31 | #include <asm/immap.h> | |
32 | #include <asm/io.h> | |
33 | ||
34 | DECLARE_GLOBAL_DATA_PTR; | |
35 | ||
36 | /* PLL min/max specifications */ | |
37 | #define MAX_FVCO 500000 /* KHz */ | |
38 | #define MAX_FSYS 80000 /* KHz */ | |
39 | #define MIN_FSYS 58333 /* KHz */ | |
40 | ||
41 | #ifdef CONFIG_MCF5301x | |
42 | #define FREF 20000 /* KHz */ | |
43 | #define MAX_MFD 63 /* Multiplier */ | |
44 | #define MIN_MFD 0 /* Multiplier */ | |
45 | #define USBDIV 8 | |
46 | ||
47 | /* Low Power Divider specifications */ | |
48 | #define MIN_LPD (0) /* Divider (not encoded) */ | |
49 | #define MAX_LPD (15) /* Divider (not encoded) */ | |
50 | #define DEFAULT_LPD (0) /* Divider (not encoded) */ | |
51 | #endif | |
52 | ||
53 | #ifdef CONFIG_MCF532x | |
54 | #define FREF 16000 /* KHz */ | |
55 | #define MAX_MFD 135 /* Multiplier */ | |
56 | #define MIN_MFD 88 /* Multiplier */ | |
57 | ||
58 | /* Low Power Divider specifications */ | |
59 | #define MIN_LPD (1 << 0) /* Divider (not encoded) */ | |
60 | #define MAX_LPD (1 << 15) /* Divider (not encoded) */ | |
61 | #define DEFAULT_LPD (1 << 1) /* Divider (not encoded) */ | |
62 | #endif | |
63 | ||
64 | #define BUSDIV 6 /* Divider */ | |
65 | ||
66 | /* Get the value of the current system clock */ | |
67 | int get_sys_clock(void) | |
68 | { | |
69 | ccm_t *ccm = (ccm_t *)(MMAP_CCM); | |
70 | pll_t *pll = (pll_t *)(MMAP_PLL); | |
71 | int divider; | |
72 | ||
73 | /* Test to see if device is in LIMP mode */ | |
74 | if (in_be16(&ccm->misccr) & CCM_MISCCR_LIMP) { | |
75 | divider = in_be16(&ccm->cdr) & CCM_CDR_LPDIV(0xF); | |
76 | #ifdef CONFIG_MCF5301x | |
77 | return (FREF / (3 * (1 << divider))); | |
78 | #endif | |
79 | #ifdef CONFIG_MCF532x | |
80 | return (FREF / (2 << divider)); | |
81 | #endif | |
82 | } else { | |
83 | #ifdef CONFIG_MCF5301x | |
84 | u32 pfdr = (in_be32(&pll->pcr) & 0x3F) + 1; | |
85 | u32 refdiv = (1 << ((in_be32(&pll->pcr) & PLL_PCR_REFDIV(7)) >> 8)); | |
86 | u32 busdiv = ((in_be32(&pll->pdr) & 0x00F0) >> 4) + 1; | |
87 | ||
88 | return (((FREF * pfdr) / refdiv) / busdiv); | |
89 | #endif | |
90 | #ifdef CONFIG_MCF532x | |
91 | return (FREF * in_8(&pll->pfdr)) / (BUSDIV * 4); | |
92 | #endif | |
93 | } | |
94 | } | |
95 | ||
96 | /* | |
97 | * Initialize the Low Power Divider circuit | |
98 | * | |
99 | * Parameters: | |
100 | * div Desired system frequency divider | |
101 | * | |
102 | * Return Value: | |
103 | * The resulting output system frequency | |
104 | */ | |
105 | int clock_limp(int div) | |
106 | { | |
107 | ccm_t *ccm = (ccm_t *)(MMAP_CCM); | |
108 | u32 temp; | |
109 | ||
110 | /* Check bounds of divider */ | |
111 | if (div < MIN_LPD) | |
112 | div = MIN_LPD; | |
113 | if (div > MAX_LPD) | |
114 | div = MAX_LPD; | |
115 | ||
116 | /* Save of the current value of the SSIDIV so we don't overwrite the value */ | |
117 | temp = (in_be16(&ccm->cdr) & CCM_CDR_SSIDIV(0xFF)); | |
118 | ||
119 | /* Apply the divider to the system clock */ | |
120 | out_be16(&ccm->cdr, CCM_CDR_LPDIV(div) | CCM_CDR_SSIDIV(temp)); | |
121 | ||
122 | setbits_be16(&ccm->misccr, CCM_MISCCR_LIMP); | |
123 | ||
124 | return (FREF / (3 * (1 << div))); | |
125 | } | |
126 | ||
127 | /* Exit low power LIMP mode */ | |
128 | int clock_exit_limp(void) | |
129 | { | |
130 | ccm_t *ccm = (ccm_t *)(MMAP_CCM); | |
131 | int fout; | |
132 | ||
133 | /* Exit LIMP mode */ | |
134 | clrbits_be16(&ccm->misccr, CCM_MISCCR_LIMP); | |
135 | ||
136 | /* Wait for PLL to lock */ | |
137 | while (!(in_be16(&ccm->misccr) & CCM_MISCCR_PLL_LOCK)) | |
138 | ; | |
139 | ||
140 | fout = get_sys_clock(); | |
141 | ||
142 | return fout; | |
143 | } | |
144 | ||
145 | /* Initialize the PLL | |
146 | * | |
147 | * Parameters: | |
148 | * fref PLL reference clock frequency in KHz | |
149 | * fsys Desired PLL output frequency in KHz | |
150 | * flags Operating parameters | |
151 | * | |
152 | * Return Value: | |
153 | * The resulting output system frequency | |
154 | */ | |
155 | int clock_pll(int fsys, int flags) | |
156 | { | |
157 | #ifdef CONFIG_MCF532x | |
158 | u32 *sdram_workaround = (u32 *)(MMAP_SDRAM + 0x80); | |
159 | #endif | |
160 | sdram_t *sdram = (sdram_t *)(MMAP_SDRAM); | |
161 | pll_t *pll = (pll_t *)(MMAP_PLL); | |
162 | int fref, temp, fout, mfd; | |
163 | u32 i; | |
164 | ||
165 | fref = FREF; | |
166 | ||
167 | if (fsys == 0) { | |
168 | /* Return current PLL output */ | |
169 | #ifdef CONFIG_MCF5301x | |
170 | u32 busdiv = ((in_be32(&pll->pdr) >> 4) & 0x0F) + 1; | |
171 | mfd = (in_be32(&pll->pcr) & 0x3F) + 1; | |
172 | ||
173 | return (fref * mfd) / busdiv; | |
174 | #endif | |
175 | #ifdef CONFIG_MCF532x | |
176 | mfd = in_8(&pll->pfdr); | |
177 | ||
178 | return (fref * mfd / (BUSDIV * 4)); | |
179 | #endif | |
180 | } | |
181 | ||
182 | /* Check bounds of requested system clock */ | |
183 | if (fsys > MAX_FSYS) | |
184 | fsys = MAX_FSYS; | |
185 | ||
186 | if (fsys < MIN_FSYS) | |
187 | fsys = MIN_FSYS; | |
188 | ||
189 | /* | |
190 | * Multiplying by 100 when calculating the temp value, | |
191 | * and then dividing by 100 to calculate the mfd allows | |
192 | * for exact values without needing to include floating | |
193 | * point libraries. | |
194 | */ | |
195 | temp = (100 * fsys) / fref; | |
196 | #ifdef CONFIG_MCF5301x | |
197 | mfd = (BUSDIV * temp) / 100; | |
198 | ||
199 | /* Determine the output frequency for selected values */ | |
200 | fout = ((fref * mfd) / BUSDIV); | |
201 | #endif | |
202 | #ifdef CONFIG_MCF532x | |
203 | mfd = (4 * BUSDIV * temp) / 100; | |
204 | ||
205 | /* Determine the output frequency for selected values */ | |
206 | fout = ((fref * mfd) / (BUSDIV * 4)); | |
207 | #endif | |
208 | ||
209 | /* must not tamper with SDRAMC if running from SDRAM */ | |
210 | #if !defined(CONFIG_MONITOR_IS_IN_RAM) | |
211 | /* | |
212 | * Check to see if the SDRAM has already been initialized. | |
213 | * If it has then the SDRAM needs to be put into self refresh | |
214 | * mode before reprogramming the PLL. | |
215 | */ | |
216 | if (in_be32(&sdram->ctrl) & SDRAMC_SDCR_REF) | |
217 | clrbits_be32(&sdram->ctrl, SDRAMC_SDCR_CKE); | |
218 | ||
219 | /* | |
220 | * Initialize the PLL to generate the new system clock frequency. | |
221 | * The device must be put into LIMP mode to reprogram the PLL. | |
222 | */ | |
223 | ||
224 | /* Enter LIMP mode */ | |
225 | clock_limp(DEFAULT_LPD); | |
226 | ||
227 | #ifdef CONFIG_MCF5301x | |
228 | out_be32(&pll->pdr, | |
229 | PLL_PDR_OUTDIV1((BUSDIV / 3) - 1) | | |
230 | PLL_PDR_OUTDIV2(BUSDIV - 1) | | |
231 | PLL_PDR_OUTDIV3((BUSDIV / 2) - 1) | | |
232 | PLL_PDR_OUTDIV4(USBDIV - 1)); | |
233 | ||
234 | clrbits_be32(&pll->pcr, ~PLL_PCR_FBDIV_UNMASK); | |
235 | setbits_be32(&pll->pcr, PLL_PCR_FBDIV(mfd - 1)); | |
236 | #endif | |
237 | #ifdef CONFIG_MCF532x | |
238 | /* Reprogram PLL for desired fsys */ | |
239 | out_8(&pll->podr, | |
240 | PLL_PODR_CPUDIV(BUSDIV / 3) | PLL_PODR_BUSDIV(BUSDIV)); | |
241 | ||
242 | out_8(&pll->pfdr, mfd); | |
243 | #endif | |
244 | ||
245 | /* Exit LIMP mode */ | |
246 | clock_exit_limp(); | |
247 | ||
248 | /* Return the SDRAM to normal operation if it is in use. */ | |
249 | if (in_be32(&sdram->ctrl) & SDRAMC_SDCR_REF) | |
250 | setbits_be32(&sdram->ctrl, SDRAMC_SDCR_CKE); | |
251 | ||
252 | #ifdef CONFIG_MCF532x | |
253 | /* | |
254 | * software workaround for SDRAM opeartion after exiting LIMP | |
255 | * mode errata | |
256 | */ | |
257 | out_be32(sdram_workaround, CONFIG_SYS_SDRAM_BASE); | |
258 | #endif | |
259 | ||
260 | /* wait for DQS logic to relock */ | |
261 | for (i = 0; i < 0x200; i++) ; | |
262 | #endif /* !defined(CONFIG_MONITOR_IS_IN_RAM) */ | |
263 | ||
264 | return fout; | |
265 | } | |
266 | ||
267 | /* get_clocks() fills in gd->cpu_clock and gd->bus_clk */ | |
268 | int get_clocks(void) | |
269 | { | |
270 | gd->bus_clk = clock_pll(CONFIG_SYS_CLK / 1000, 0) * 1000; | |
271 | gd->cpu_clk = (gd->bus_clk * 3); | |
272 | ||
273 | #ifdef CONFIG_FSL_I2C | |
274 | gd->i2c1_clk = gd->bus_clk; | |
275 | #endif | |
276 | ||
277 | return (0); | |
278 | } |