77 lines
		
	
	
		
			1.5 KiB
		
	
	
	
		
			C
		
	
	
	
			
		
		
	
	
			77 lines
		
	
	
		
			1.5 KiB
		
	
	
	
		
			C
		
	
	
	
| /*
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|  * Copyright (C) 2016 Atmel Corporation
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|  *               Wenyou.Yang <wenyou.yang@atmel.com>
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|  *
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|  * SPDX-License-Identifier:	GPL-2.0+
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|  */
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| 
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| #include <common.h>
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| #include <clk-uclass.h>
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| #include <dm/device.h>
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| #include <linux/io.h>
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| #include <mach/at91_pmc.h>
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| #include "pmc.h"
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| 
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| #define SYSTEM_MAX_ID		31
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| 
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| static inline int is_pck(int id)
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| {
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| 	return (id >= 8) && (id <= 15);
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| }
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| 
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| static int at91_system_clk_enable(struct clk *clk)
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| {
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| 	struct pmc_platdata *plat = dev_get_platdata(clk->dev);
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| 	struct at91_pmc *pmc = plat->reg_base;
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| 	u32 mask;
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| 
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| 	if (clk->id > SYSTEM_MAX_ID)
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| 		return -EINVAL;
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| 
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| 	mask = BIT(clk->id);
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| 
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| 	writel(mask, &pmc->scer);
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| 
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| 	/**
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| 	 * For the programmable clocks the Ready status in the PMC
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| 	 * status register should be checked after enabling.
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| 	 * For other clocks this is unnecessary.
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| 	 */
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| 	if (!is_pck(clk->id))
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| 		return 0;
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| 
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| 	while (!(readl(&pmc->sr) & mask))
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| 		;
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| 
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| 	return 0;
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| }
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| 
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| static struct clk_ops at91_system_clk_ops = {
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| 	.enable = at91_system_clk_enable,
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| };
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| 
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| static int at91_system_clk_bind(struct udevice *dev)
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| {
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| 	return at91_pmc_clk_node_bind(dev);
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| }
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| 
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| static int at91_system_clk_probe(struct udevice *dev)
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| {
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| 	return at91_pmc_core_probe(dev);
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| }
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| 
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| static const struct udevice_id at91_system_clk_match[] = {
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| 	{ .compatible = "atmel,at91rm9200-clk-system" },
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| 	{}
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| };
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| 
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| U_BOOT_DRIVER(at91_system_clk) = {
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| 	.name = "at91-system-clk",
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| 	.id = UCLASS_CLK,
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| 	.of_match = at91_system_clk_match,
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| 	.bind = at91_system_clk_bind,
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| 	.probe = at91_system_clk_probe,
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| 	.platdata_auto_alloc_size = sizeof(struct pmc_platdata),
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| 	.ops = &at91_system_clk_ops,
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| };
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