xref: /openbmc/u-boot/arch/m68k/cpu/mcf5445x/speed.c (revision ecd4551f)
1 /*
2  *
3  * Copyright (C) 2004-2007, 2012 Freescale Semiconductor, Inc.
4  * TsiChung Liew (Tsi-Chung.Liew@freescale.com)
5  *
6  * See file CREDITS for list of people who contributed to this
7  * project.
8  *
9  * This program is free software; you can redistribute it and/or
10  * modify it under the terms of the GNU General Public License as
11  * published by the Free Software Foundation; either version 2 of
12  * the License, or (at your option) any later version.
13  *
14  * This program is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17  * GNU General Public License for more details.
18  *
19  * You should have received a copy of the GNU General Public License
20  * along with this program; if not, write to the Free Software
21  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
22  * MA 02111-1307 USA
23  */
24 
25 #include <common.h>
26 #include <asm/processor.h>
27 
28 #include <asm/immap.h>
29 #include <asm/io.h>
30 
31 DECLARE_GLOBAL_DATA_PTR;
32 
33 /*
34  * Low Power Divider specifications
35  */
36 #define CLOCK_LPD_MIN		(1 << 0)	/* Divider (decoded) */
37 #define CLOCK_LPD_MAX		(1 << 15)	/* Divider (decoded) */
38 
39 #define CLOCK_PLL_FVCO_MAX	540000000
40 #define CLOCK_PLL_FVCO_MIN	300000000
41 
42 #define CLOCK_PLL_FSYS_MAX	266666666
43 #define CLOCK_PLL_FSYS_MIN	100000000
44 #define MHZ			1000000
45 
46 void clock_enter_limp(int lpdiv)
47 {
48 	ccm_t *ccm = (ccm_t *)MMAP_CCM;
49 	int i, j;
50 
51 	/* Check bounds of divider */
52 	if (lpdiv < CLOCK_LPD_MIN)
53 		lpdiv = CLOCK_LPD_MIN;
54 	if (lpdiv > CLOCK_LPD_MAX)
55 		lpdiv = CLOCK_LPD_MAX;
56 
57 	/* Round divider down to nearest power of two */
58 	for (i = 0, j = lpdiv; j != 1; j >>= 1, i++) ;
59 
60 	/* Apply the divider to the system clock */
61 	clrsetbits_be16(&ccm->cdr, 0x0f00, CCM_CDR_LPDIV(i));
62 
63 	/* Enable Limp Mode */
64 	setbits_be16(&ccm->misccr, CCM_MISCCR_LIMP);
65 }
66 
67 /*
68  * brief   Exit Limp mode
69  * warning The PLL should be set and locked prior to exiting Limp mode
70  */
71 void clock_exit_limp(void)
72 {
73 	ccm_t *ccm = (ccm_t *)MMAP_CCM;
74 	pll_t *pll = (pll_t *)MMAP_PLL;
75 
76 	/* Exit Limp mode */
77 	clrbits_be16(&ccm->misccr, CCM_MISCCR_LIMP);
78 
79 	/* Wait for the PLL to lock */
80 	while (!(in_be32(&pll->psr) & PLL_PSR_LOCK))
81 		;
82 }
83 
84 /*
85  * get_clocks() fills in gd->cpu_clock and gd->bus_clk
86  */
87 int get_clocks(void)
88 {
89 
90 	ccm_t *ccm = (ccm_t *)MMAP_CCM;
91 	pll_t *pll = (pll_t *)MMAP_PLL;
92 	int pllmult_nopci[] = { 20, 10, 24, 18, 12, 6, 16, 8 };
93 	int pllmult_pci[] = { 12, 6, 16, 8 };
94 	int vco = 0, temp, fbtemp, pcrvalue;
95 	int *pPllmult = NULL;
96 	u16 fbpll_mask;
97 #ifdef CONFIG_PCI
98 	int bPci;
99 #endif
100 
101 #ifdef CONFIG_M54455EVB
102 	u8 *cpld = (u8 *)(CONFIG_SYS_CS2_BASE + 3);
103 #endif
104 	u8 bootmode;
105 
106 	/* To determine PCI is present or not */
107 	if (((in_be16(&ccm->ccr) & CCM_CCR_360_FBCONFIG_MASK) == 0x00e0) ||
108 	    ((in_be16(&ccm->ccr) & CCM_CCR_360_FBCONFIG_MASK) == 0x0060)) {
109 		pPllmult = &pllmult_pci[0];
110 		fbpll_mask = 3;		/* 11b */
111 #ifdef CONFIG_PCI
112 		bPci = 1;
113 #endif
114 	} else {
115 		pPllmult = &pllmult_nopci[0];
116 		fbpll_mask = 7;		/* 111b */
117 #ifdef CONFIG_PCI
118 		gd->pci_clk = 0;
119 		bPci = 0;
120 #endif
121 	}
122 
123 #ifdef CONFIG_M54455EVB
124 	bootmode = (in_8(cpld) & 0x03);
125 
126 	if (bootmode != 3) {
127 		/* Temporary read from CCR- fixed fb issue, must be the same clock
128 		   as pci or input clock, causing cpld/fpga read inconsistancy */
129 		fbtemp = pPllmult[ccm->ccr & fbpll_mask];
130 
131 		/* Break down into small pieces, code still in flex bus */
132 		pcrvalue = in_be32(&pll->pcr) & 0xFFFFF0FF;
133 		temp = fbtemp - 1;
134 		pcrvalue |= PLL_PCR_OUTDIV3(temp);
135 
136 		out_be32(&pll->pcr, pcrvalue);
137 	}
138 #endif
139 #ifdef CONFIG_M54451EVB
140 	/* No external logic to read the bootmode, hard coded from built */
141 #ifdef CONFIG_CF_SBF
142 	bootmode = 3;
143 #else
144 	bootmode = 2;
145 
146 	/* default value is 16 mul, set to 20 mul */
147 	pcrvalue = (in_be32(&pll->pcr) & 0x00FFFFFF) | 0x14000000;
148 	out_be32(&pll->pcr, pcrvalue);
149 	while ((in_be32(&pll->psr) & PLL_PSR_LOCK) != PLL_PSR_LOCK)
150 		;
151 #endif
152 #endif
153 
154 	if (bootmode == 0) {
155 		/* RCON mode */
156 		vco = pPllmult[ccm->rcon & fbpll_mask] * CONFIG_SYS_INPUT_CLKSRC;
157 
158 		if ((vco < CLOCK_PLL_FVCO_MIN) || (vco > CLOCK_PLL_FVCO_MAX)) {
159 			/* invaild range, re-set in PCR */
160 			int temp = ((in_be32(&pll->pcr) & PLL_PCR_OUTDIV2_MASK) >> 4) + 1;
161 			int i, j, bus;
162 
163 			j = (in_be32(&pll->pcr) & 0xFF000000) >> 24;
164 			for (i = j; i < 0xFF; i++) {
165 				vco = i * CONFIG_SYS_INPUT_CLKSRC;
166 				if (vco >= CLOCK_PLL_FVCO_MIN) {
167 					bus = vco / temp;
168 					if (bus <= CLOCK_PLL_FSYS_MIN - MHZ)
169 						continue;
170 					else
171 						break;
172 				}
173 			}
174 			pcrvalue = in_be32(&pll->pcr) & 0x00FF00FF;
175 			fbtemp = ((i - 1) << 8) | ((i - 1) << 12);
176 			pcrvalue |= ((i << 24) | fbtemp);
177 
178 			out_be32(&pll->pcr, pcrvalue);
179 		}
180 		gd->vco_clk = vco;	/* Vco clock */
181 	} else if (bootmode == 2) {
182 		/* Normal mode */
183 		vco =  ((in_be32(&pll->pcr) & 0xFF000000) >> 24) * CONFIG_SYS_INPUT_CLKSRC;
184 		if ((vco < CLOCK_PLL_FVCO_MIN) || (vco > CLOCK_PLL_FVCO_MAX)) {
185 			/* Default value */
186 			pcrvalue = (in_be32(&pll->pcr) & 0x00FFFFFF);
187 			pcrvalue |= pPllmult[in_be16(&ccm->ccr) & fbpll_mask] << 24;
188 			out_be32(&pll->pcr, pcrvalue);
189 			vco = ((in_be32(&pll->pcr) & 0xFF000000) >> 24) * CONFIG_SYS_INPUT_CLKSRC;
190 		}
191 		gd->vco_clk = vco;	/* Vco clock */
192 	} else if (bootmode == 3) {
193 		/* serial mode */
194 		vco =  ((in_be32(&pll->pcr) & 0xFF000000) >> 24) * CONFIG_SYS_INPUT_CLKSRC;
195 		gd->vco_clk = vco;	/* Vco clock */
196 	}
197 
198 	if ((in_be16(&ccm->ccr) & CCM_MISCCR_LIMP) == CCM_MISCCR_LIMP) {
199 		/* Limp mode */
200 	} else {
201 		gd->inp_clk = CONFIG_SYS_INPUT_CLKSRC;	/* Input clock */
202 
203 		temp = (in_be32(&pll->pcr) & PLL_PCR_OUTDIV1_MASK) + 1;
204 		gd->cpu_clk = vco / temp;	/* cpu clock */
205 
206 		temp = ((in_be32(&pll->pcr) & PLL_PCR_OUTDIV2_MASK) >> 4) + 1;
207 		gd->bus_clk = vco / temp;	/* bus clock */
208 
209 		temp = ((in_be32(&pll->pcr) & PLL_PCR_OUTDIV3_MASK) >> 8) + 1;
210 		gd->flb_clk = vco / temp;	/* FlexBus clock */
211 
212 #ifdef CONFIG_PCI
213 		if (bPci) {
214 			temp = ((in_be32(&pll->pcr) & PLL_PCR_OUTDIV4_MASK) >> 12) + 1;
215 			gd->pci_clk = vco / temp;	/* PCI clock */
216 		}
217 #endif
218 	}
219 
220 #ifdef CONFIG_FSL_I2C
221 	gd->i2c1_clk = gd->bus_clk;
222 #endif
223 
224 	return (0);
225 }
226