103 lines
		
	
	
	
		
			2.4 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
		
		
			
		
	
	
			103 lines
		
	
	
	
		
			2.4 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
|   | /*
 | ||
|  |  * PowerQUICC II support functions | ||
|  |  * | ||
|  |  * Author: Scott Wood <scottwood@freescale.com> | ||
|  |  * | ||
|  |  * Copyright (c) 2007 Freescale Semiconductor, Inc. | ||
|  |  * | ||
|  |  * This program is free software; you can redistribute it and/or modify it | ||
|  |  * under the terms of the GNU General Public License version 2 as published | ||
|  |  * by the Free Software Foundation. | ||
|  |  */ | ||
|  | 
 | ||
|  | #include "ops.h"
 | ||
|  | #include "types.h"
 | ||
|  | #include "fsl-soc.h"
 | ||
|  | #include "pq2.h"
 | ||
|  | #include "stdio.h"
 | ||
|  | #include "io.h"
 | ||
|  | 
 | ||
|  | #define PQ2_SCCR (0x10c80/4) /* System Clock Configuration Register */
 | ||
|  | #define PQ2_SCMR (0x10c88/4) /* System Clock Mode Register */
 | ||
|  | 
 | ||
|  | static int pq2_corecnf_map[] = { | ||
|  | 	3, 2, 2, 2, 4, 4, 5, 9, 6, 11, 8, 10, 3, 12, 7, -1, | ||
|  | 	6, 5, 13, 2, 14, 4, 15, 9, 0, 11, 8, 10, 16, 12, 7, -1 | ||
|  | }; | ||
|  | 
 | ||
|  | /* Get various clocks from crystal frequency.
 | ||
|  |  * Returns zero on failure and non-zero on success. | ||
|  |  */ | ||
|  | int pq2_get_clocks(u32 crystal, u32 *sysfreq, u32 *corefreq, | ||
|  |                    u32 *timebase, u32 *brgfreq) | ||
|  | { | ||
|  | 	u32 *immr; | ||
|  | 	u32 sccr, scmr, mainclk, busclk; | ||
|  | 	int corecnf, busdf, plldf, pllmf, dfbrg; | ||
|  | 
 | ||
|  | 	immr = fsl_get_immr(); | ||
|  | 	if (!immr) { | ||
|  | 		printf("pq2_get_clocks: Couldn't get IMMR base.\r\n"); | ||
|  | 		return 0; | ||
|  | 	} | ||
|  | 
 | ||
|  | 	sccr = in_be32(&immr[PQ2_SCCR]); | ||
|  | 	scmr = in_be32(&immr[PQ2_SCMR]); | ||
|  | 
 | ||
|  | 	dfbrg = sccr & 3; | ||
|  | 	corecnf = (scmr >> 24) & 0x1f; | ||
|  | 	busdf = (scmr >> 20) & 0xf; | ||
|  | 	plldf = (scmr >> 12) & 1; | ||
|  | 	pllmf = scmr & 0xfff; | ||
|  | 
 | ||
|  | 	mainclk = crystal * (pllmf + 1) / (plldf + 1); | ||
|  | 	busclk = mainclk / (busdf + 1); | ||
|  | 
 | ||
|  | 	if (sysfreq) | ||
|  | 		*sysfreq = mainclk / 2; | ||
|  | 	if (timebase) | ||
|  | 		*timebase = busclk / 4; | ||
|  | 	if (brgfreq) | ||
|  | 		*brgfreq = mainclk / (1 << ((dfbrg + 1) * 2)); | ||
|  | 
 | ||
|  | 	if (corefreq) { | ||
|  | 		int coremult = pq2_corecnf_map[corecnf]; | ||
|  | 
 | ||
|  | 		if (coremult < 0) | ||
|  | 			*corefreq = mainclk / 2; | ||
|  | 		else if (coremult == 0) | ||
|  | 			return 0; | ||
|  | 		else | ||
|  | 			*corefreq = busclk * coremult / 2; | ||
|  | 	} | ||
|  | 
 | ||
|  | 	return 1; | ||
|  | } | ||
|  | 
 | ||
|  | /* Set common device tree fields based on the given clock frequencies. */ | ||
|  | void pq2_set_clocks(u32 sysfreq, u32 corefreq, u32 timebase, u32 brgfreq) | ||
|  | { | ||
|  | 	void *node; | ||
|  | 
 | ||
|  | 	dt_fixup_cpu_clocks(corefreq, timebase, sysfreq); | ||
|  | 
 | ||
|  | 	node = finddevice("/soc/cpm"); | ||
|  | 	if (node) | ||
|  | 		setprop(node, "clock-frequency", &sysfreq, 4); | ||
|  | 
 | ||
|  | 	node = finddevice("/soc/cpm/brg"); | ||
|  | 	if (node) | ||
|  | 		setprop(node, "clock-frequency", &brgfreq, 4); | ||
|  | } | ||
|  | 
 | ||
|  | int pq2_fixup_clocks(u32 crystal) | ||
|  | { | ||
|  | 	u32 sysfreq, corefreq, timebase, brgfreq; | ||
|  | 
 | ||
|  | 	if (!pq2_get_clocks(crystal, &sysfreq, &corefreq, &timebase, &brgfreq)) | ||
|  | 		return 0; | ||
|  | 
 | ||
|  | 	pq2_set_clocks(sysfreq, corefreq, timebase, brgfreq); | ||
|  | 	return 1; | ||
|  | } |