xref: /OK3568_Linux_fs/u-boot/arch/m68k/cpu/mcf5227x/speed.c (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun /*
2*4882a593Smuzhiyun  *
3*4882a593Smuzhiyun  * Copyright (C) 2004-2007, 2012 Freescale Semiconductor, Inc.
4*4882a593Smuzhiyun  * TsiChung Liew (Tsi-Chung.Liew@freescale.com)
5*4882a593Smuzhiyun  *
6*4882a593Smuzhiyun  * SPDX-License-Identifier:	GPL-2.0+
7*4882a593Smuzhiyun  */
8*4882a593Smuzhiyun 
9*4882a593Smuzhiyun #include <common.h>
10*4882a593Smuzhiyun #include <asm/processor.h>
11*4882a593Smuzhiyun 
12*4882a593Smuzhiyun #include <asm/immap.h>
13*4882a593Smuzhiyun #include <asm/io.h>
14*4882a593Smuzhiyun 
15*4882a593Smuzhiyun DECLARE_GLOBAL_DATA_PTR;
16*4882a593Smuzhiyun 
17*4882a593Smuzhiyun /*
18*4882a593Smuzhiyun  * Low Power Divider specifications
19*4882a593Smuzhiyun  */
20*4882a593Smuzhiyun #define CLOCK_LPD_MIN		(1 << 0)	/* Divider (decoded) */
21*4882a593Smuzhiyun #define CLOCK_LPD_MAX		(1 << 15)	/* Divider (decoded) */
22*4882a593Smuzhiyun 
23*4882a593Smuzhiyun #define CLOCK_PLL_FVCO_MAX	540000000
24*4882a593Smuzhiyun #define CLOCK_PLL_FVCO_MIN	300000000
25*4882a593Smuzhiyun 
26*4882a593Smuzhiyun #define CLOCK_PLL_FSYS_MAX	266666666
27*4882a593Smuzhiyun #define CLOCK_PLL_FSYS_MIN	100000000
28*4882a593Smuzhiyun #define MHZ			1000000
29*4882a593Smuzhiyun 
clock_enter_limp(int lpdiv)30*4882a593Smuzhiyun void clock_enter_limp(int lpdiv)
31*4882a593Smuzhiyun {
32*4882a593Smuzhiyun 	ccm_t *ccm = (ccm_t *)MMAP_CCM;
33*4882a593Smuzhiyun 	int i, j;
34*4882a593Smuzhiyun 
35*4882a593Smuzhiyun 	/* Check bounds of divider */
36*4882a593Smuzhiyun 	if (lpdiv < CLOCK_LPD_MIN)
37*4882a593Smuzhiyun 		lpdiv = CLOCK_LPD_MIN;
38*4882a593Smuzhiyun 	if (lpdiv > CLOCK_LPD_MAX)
39*4882a593Smuzhiyun 		lpdiv = CLOCK_LPD_MAX;
40*4882a593Smuzhiyun 
41*4882a593Smuzhiyun 	/* Round divider down to nearest power of two */
42*4882a593Smuzhiyun 	for (i = 0, j = lpdiv; j != 1; j >>= 1, i++) ;
43*4882a593Smuzhiyun 
44*4882a593Smuzhiyun 	/* Apply the divider to the system clock */
45*4882a593Smuzhiyun 	clrsetbits_be16(&ccm->cdr, 0x0f00, CCM_CDR_LPDIV(i));
46*4882a593Smuzhiyun 
47*4882a593Smuzhiyun 	/* Enable Limp Mode */
48*4882a593Smuzhiyun 	setbits_be16(&ccm->misccr, CCM_MISCCR_LIMP);
49*4882a593Smuzhiyun }
50*4882a593Smuzhiyun 
51*4882a593Smuzhiyun /*
52*4882a593Smuzhiyun  * brief   Exit Limp mode
53*4882a593Smuzhiyun  * warning The PLL should be set and locked prior to exiting Limp mode
54*4882a593Smuzhiyun  */
clock_exit_limp(void)55*4882a593Smuzhiyun void clock_exit_limp(void)
56*4882a593Smuzhiyun {
57*4882a593Smuzhiyun 	ccm_t *ccm = (ccm_t *)MMAP_CCM;
58*4882a593Smuzhiyun 	pll_t *pll = (pll_t *)MMAP_PLL;
59*4882a593Smuzhiyun 
60*4882a593Smuzhiyun 	/* Exit Limp mode */
61*4882a593Smuzhiyun 	clrbits_be16(&ccm->misccr, CCM_MISCCR_LIMP);
62*4882a593Smuzhiyun 
63*4882a593Smuzhiyun 	/* Wait for the PLL to lock */
64*4882a593Smuzhiyun 	while (!(in_be32(&pll->psr) & PLL_PSR_LOCK))
65*4882a593Smuzhiyun 		;
66*4882a593Smuzhiyun }
67*4882a593Smuzhiyun 
68*4882a593Smuzhiyun /*
69*4882a593Smuzhiyun  * get_clocks() fills in gd->cpu_clock and gd->bus_clk
70*4882a593Smuzhiyun  */
get_clocks(void)71*4882a593Smuzhiyun int get_clocks(void)
72*4882a593Smuzhiyun {
73*4882a593Smuzhiyun 
74*4882a593Smuzhiyun 	ccm_t *ccm = (ccm_t *)MMAP_CCM;
75*4882a593Smuzhiyun 	pll_t *pll = (pll_t *)MMAP_PLL;
76*4882a593Smuzhiyun 	int vco, temp, pcrvalue, pfdr;
77*4882a593Smuzhiyun 	u8 bootmode;
78*4882a593Smuzhiyun 
79*4882a593Smuzhiyun 	pcrvalue = in_be32(&pll->pcr) & 0xFF0F0FFF;
80*4882a593Smuzhiyun 	pfdr = pcrvalue >> 24;
81*4882a593Smuzhiyun 
82*4882a593Smuzhiyun 	if (pfdr == 0x1E)
83*4882a593Smuzhiyun 		bootmode = 0;	/* Normal Mode */
84*4882a593Smuzhiyun 
85*4882a593Smuzhiyun #ifdef CONFIG_CF_SBF
86*4882a593Smuzhiyun 	bootmode = 3;		/* Serial Mode */
87*4882a593Smuzhiyun #endif
88*4882a593Smuzhiyun 
89*4882a593Smuzhiyun 	if (bootmode == 0) {
90*4882a593Smuzhiyun 		/* Normal mode */
91*4882a593Smuzhiyun 		vco = ((in_be32(&pll->pcr) & 0xFF000000) >> 24) * CONFIG_SYS_INPUT_CLKSRC;
92*4882a593Smuzhiyun 		if ((vco < CLOCK_PLL_FVCO_MIN) || (vco > CLOCK_PLL_FVCO_MAX)) {
93*4882a593Smuzhiyun 			/* Default value */
94*4882a593Smuzhiyun 			pcrvalue = (in_be32(&pll->pcr) & 0x00FFFFFF);
95*4882a593Smuzhiyun 			pcrvalue |= 0x1E << 24;
96*4882a593Smuzhiyun 			out_be32(&pll->pcr, pcrvalue);
97*4882a593Smuzhiyun 			vco =
98*4882a593Smuzhiyun 			    ((in_be32(&pll->pcr) & 0xFF000000) >> 24) *
99*4882a593Smuzhiyun 			    CONFIG_SYS_INPUT_CLKSRC;
100*4882a593Smuzhiyun 		}
101*4882a593Smuzhiyun 		gd->arch.vco_clk = vco;	/* Vco clock */
102*4882a593Smuzhiyun 	} else if (bootmode == 3) {
103*4882a593Smuzhiyun 		/* serial mode */
104*4882a593Smuzhiyun 		vco = ((in_be32(&pll->pcr) & 0xFF000000) >> 24) * CONFIG_SYS_INPUT_CLKSRC;
105*4882a593Smuzhiyun 		gd->arch.vco_clk = vco;	/* Vco clock */
106*4882a593Smuzhiyun 	}
107*4882a593Smuzhiyun 
108*4882a593Smuzhiyun 	if ((in_be16(&ccm->ccr) & CCM_MISCCR_LIMP) == CCM_MISCCR_LIMP) {
109*4882a593Smuzhiyun 		/* Limp mode */
110*4882a593Smuzhiyun 	} else {
111*4882a593Smuzhiyun 		gd->arch.inp_clk = CONFIG_SYS_INPUT_CLKSRC; /* Input clock */
112*4882a593Smuzhiyun 
113*4882a593Smuzhiyun 		temp = (in_be32(&pll->pcr) & PLL_PCR_OUTDIV1_MASK) + 1;
114*4882a593Smuzhiyun 		gd->cpu_clk = vco / temp;	/* cpu clock */
115*4882a593Smuzhiyun 
116*4882a593Smuzhiyun 		temp = ((in_be32(&pll->pcr) & PLL_PCR_OUTDIV2_MASK) >> 4) + 1;
117*4882a593Smuzhiyun 		gd->arch.flb_clk = vco / temp;	/* flexbus clock */
118*4882a593Smuzhiyun 		gd->bus_clk = gd->arch.flb_clk;
119*4882a593Smuzhiyun 	}
120*4882a593Smuzhiyun 
121*4882a593Smuzhiyun #ifdef CONFIG_SYS_I2C_FSL
122*4882a593Smuzhiyun 	gd->arch.i2c1_clk = gd->bus_clk;
123*4882a593Smuzhiyun #endif
124*4882a593Smuzhiyun 
125*4882a593Smuzhiyun 	return (0);
126*4882a593Smuzhiyun }
127