xref: /openbmc/u-boot/arch/m68k/cpu/mcf52x2/speed.c (revision fd697ecf)
1 /*
2  * (C) Copyright 2003
3  * Josef Baumgartner <josef.baumgartner@telex.de>
4  *
5  * Copyright (C) 2004-2007, 2012 Freescale Semiconductor, Inc.
6  * Hayden Fraser (Hayden.Fraser@freescale.com)
7  *
8  * SPDX-License-Identifier:	GPL-2.0+
9  */
10 
11 #include <common.h>
12 #include <asm/processor.h>
13 #include <asm/immap.h>
14 #include <asm/io.h>
15 
16 DECLARE_GLOBAL_DATA_PTR;
17 
18 /* get_clocks() fills in gd->cpu_clock and gd->bus_clk */
19 int get_clocks (void)
20 {
21 #if defined(CONFIG_M5208)
22 	pll_t *pll = (pll_t *) MMAP_PLL;
23 
24 	out_8(&pll->odr, CONFIG_SYS_PLL_ODR);
25 	out_8(&pll->fdr, CONFIG_SYS_PLL_FDR);
26 #endif
27 
28 #if defined(CONFIG_M5249) || defined(CONFIG_M5253)
29 	volatile unsigned long cpll = mbar2_readLong(MCFSIM_PLLCR);
30 	unsigned long pllcr;
31 
32 #ifndef CONFIG_SYS_PLL_BYPASS
33 
34 #ifdef CONFIG_M5249
35 	/* Setup the PLL to run at the specified speed */
36 #ifdef CONFIG_SYS_FAST_CLK
37 	pllcr = 0x925a3100;	/* ~140MHz clock (PLL bypass = 0) */
38 #else
39 	pllcr = 0x135a4140;	/* ~72MHz clock (PLL bypass = 0) */
40 #endif
41 #endif				/* CONFIG_M5249 */
42 
43 #ifdef CONFIG_M5253
44 	pllcr = CONFIG_SYS_PLLCR;
45 #endif				/* CONFIG_M5253 */
46 
47 	cpll = cpll & 0xfffffffe;	/* Set PLL bypass mode = 0 (PSTCLK = crystal) */
48 	mbar2_writeLong(MCFSIM_PLLCR, cpll);	/* Set the PLL to bypass mode (PSTCLK = crystal) */
49 	mbar2_writeLong(MCFSIM_PLLCR, pllcr);	/* set the clock speed */
50 	pllcr ^= 0x00000001;	/* Set pll bypass to 1 */
51 	mbar2_writeLong(MCFSIM_PLLCR, pllcr);	/* Start locking (pll bypass = 1) */
52 	udelay(0x20);		/* Wait for a lock ... */
53 #endif				/* #ifndef CONFIG_SYS_PLL_BYPASS */
54 
55 #endif				/* CONFIG_M5249 || CONFIG_M5253 */
56 
57 #if defined(CONFIG_M5275)
58 	pll_t *pll = (pll_t *)(MMAP_PLL);
59 
60 	/* Setup PLL */
61 	out_be32(&pll->syncr, 0x01080000);
62 	while (!(in_be32(&pll->synsr) & FMPLL_SYNSR_LOCK))
63 		;
64 	out_be32(&pll->syncr, 0x01000000);
65 	while (!(in_be32(&pll->synsr) & FMPLL_SYNSR_LOCK))
66 		;
67 #endif
68 
69 	gd->cpu_clk = CONFIG_SYS_CLK;
70 #if defined(CONFIG_M5208) || defined(CONFIG_M5249) || defined(CONFIG_M5253) || \
71     defined(CONFIG_M5271) || defined(CONFIG_M5275)
72 	gd->bus_clk = gd->cpu_clk / 2;
73 #else
74 	gd->bus_clk = gd->cpu_clk;
75 #endif
76 
77 #ifdef CONFIG_SYS_I2C_FSL
78 	gd->arch.i2c1_clk = gd->bus_clk;
79 #ifdef CONFIG_SYS_I2C2_FSL_OFFSET
80 	gd->arch.i2c2_clk = gd->bus_clk;
81 #endif
82 #endif
83 
84 	return (0);
85 }
86