xref: /openbmc/u-boot/arch/m68k/cpu/mcf5445x/speed.c (revision 6f6ea814)
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, bPci, temp, fbtemp, pcrvalue;
95 	int *pPllmult = NULL;
96 	u16 fbpll_mask;
97 
98 #ifdef CONFIG_M54455EVB
99 	u8 *cpld = (u8 *)(CONFIG_SYS_CS2_BASE + 3);
100 #endif
101 	u8 bootmode;
102 
103 	/* To determine PCI is present or not */
104 	if (((in_be16(&ccm->ccr) & CCM_CCR_360_FBCONFIG_MASK) == 0x00e0) ||
105 	    ((in_be16(&ccm->ccr) & CCM_CCR_360_FBCONFIG_MASK) == 0x0060)) {
106 		pPllmult = &pllmult_pci[0];
107 		fbpll_mask = 3;		/* 11b */
108 		bPci = 1;
109 	} else {
110 		pPllmult = &pllmult_nopci[0];
111 		fbpll_mask = 7;		/* 111b */
112 #ifdef CONFIG_PCI
113 		gd->pci_clk = 0;
114 #endif
115 		bPci = 0;
116 	}
117 
118 #ifdef CONFIG_M54455EVB
119 	bootmode = (in_8(cpld) & 0x03);
120 
121 	if (bootmode != 3) {
122 		/* Temporary read from CCR- fixed fb issue, must be the same clock
123 		   as pci or input clock, causing cpld/fpga read inconsistancy */
124 		fbtemp = pPllmult[ccm->ccr & fbpll_mask];
125 
126 		/* Break down into small pieces, code still in flex bus */
127 		pcrvalue = in_be32(&pll->pcr) & 0xFFFFF0FF;
128 		temp = fbtemp - 1;
129 		pcrvalue |= PLL_PCR_OUTDIV3(temp);
130 
131 		out_be32(&pll->pcr, pcrvalue);
132 	}
133 #endif
134 #ifdef CONFIG_M54451EVB
135 	/* No external logic to read the bootmode, hard coded from built */
136 #ifdef CONFIG_CF_SBF
137 	bootmode = 3;
138 #else
139 	bootmode = 2;
140 
141 	/* default value is 16 mul, set to 20 mul */
142 	pcrvalue = (in_be32(&pll->pcr) & 0x00FFFFFF) | 0x14000000;
143 	out_be32(&pll->pcr, pcrvalue);
144 	while ((in_be32(&pll->psr) & PLL_PSR_LOCK) != PLL_PSR_LOCK)
145 		;
146 #endif
147 #endif
148 
149 	if (bootmode == 0) {
150 		/* RCON mode */
151 		vco = pPllmult[ccm->rcon & fbpll_mask] * CONFIG_SYS_INPUT_CLKSRC;
152 
153 		if ((vco < CLOCK_PLL_FVCO_MIN) || (vco > CLOCK_PLL_FVCO_MAX)) {
154 			/* invaild range, re-set in PCR */
155 			int temp = ((in_be32(&pll->pcr) & PLL_PCR_OUTDIV2_MASK) >> 4) + 1;
156 			int i, j, bus;
157 
158 			j = (in_be32(&pll->pcr) & 0xFF000000) >> 24;
159 			for (i = j; i < 0xFF; i++) {
160 				vco = i * CONFIG_SYS_INPUT_CLKSRC;
161 				if (vco >= CLOCK_PLL_FVCO_MIN) {
162 					bus = vco / temp;
163 					if (bus <= CLOCK_PLL_FSYS_MIN - MHZ)
164 						continue;
165 					else
166 						break;
167 				}
168 			}
169 			pcrvalue = in_be32(&pll->pcr) & 0x00FF00FF;
170 			fbtemp = ((i - 1) << 8) | ((i - 1) << 12);
171 			pcrvalue |= ((i << 24) | fbtemp);
172 
173 			out_be32(&pll->pcr, pcrvalue);
174 		}
175 		gd->vco_clk = vco;	/* Vco clock */
176 	} else if (bootmode == 2) {
177 		/* Normal mode */
178 		vco =  ((in_be32(&pll->pcr) & 0xFF000000) >> 24) * CONFIG_SYS_INPUT_CLKSRC;
179 		if ((vco < CLOCK_PLL_FVCO_MIN) || (vco > CLOCK_PLL_FVCO_MAX)) {
180 			/* Default value */
181 			pcrvalue = (in_be32(&pll->pcr) & 0x00FFFFFF);
182 			pcrvalue |= pPllmult[in_be16(&ccm->ccr) & fbpll_mask] << 24;
183 			out_be32(&pll->pcr, pcrvalue);
184 			vco = ((in_be32(&pll->pcr) & 0xFF000000) >> 24) * CONFIG_SYS_INPUT_CLKSRC;
185 		}
186 		gd->vco_clk = vco;	/* Vco clock */
187 	} else if (bootmode == 3) {
188 		/* serial mode */
189 		vco =  ((in_be32(&pll->pcr) & 0xFF000000) >> 24) * CONFIG_SYS_INPUT_CLKSRC;
190 		gd->vco_clk = vco;	/* Vco clock */
191 	}
192 
193 	if ((in_be16(&ccm->ccr) & CCM_MISCCR_LIMP) == CCM_MISCCR_LIMP) {
194 		/* Limp mode */
195 	} else {
196 		gd->inp_clk = CONFIG_SYS_INPUT_CLKSRC;	/* Input clock */
197 
198 		temp = (in_be32(&pll->pcr) & PLL_PCR_OUTDIV1_MASK) + 1;
199 		gd->cpu_clk = vco / temp;	/* cpu clock */
200 
201 		temp = ((in_be32(&pll->pcr) & PLL_PCR_OUTDIV2_MASK) >> 4) + 1;
202 		gd->bus_clk = vco / temp;	/* bus clock */
203 
204 		temp = ((in_be32(&pll->pcr) & PLL_PCR_OUTDIV3_MASK) >> 8) + 1;
205 		gd->flb_clk = vco / temp;	/* FlexBus clock */
206 
207 #ifdef CONFIG_PCI
208 		if (bPci) {
209 			temp = ((in_be32(&pll->pcr) & PLL_PCR_OUTDIV4_MASK) >> 12) + 1;
210 			gd->pci_clk = vco / temp;	/* PCI clock */
211 		}
212 #endif
213 	}
214 
215 #ifdef CONFIG_FSL_I2C
216 	gd->i2c1_clk = gd->bus_clk;
217 #endif
218 
219 	return (0);
220 }
221