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	This subsystem is present on various Intel SoCs. Add very basic support for taking an lpss device out of reset. Signed-off-by: Simon Glass <sjg@chromium.org> Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
		
			
				
	
	
		
			45 lines
		
	
	
		
			955 B
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			45 lines
		
	
	
		
			955 B
		
	
	
	
		
			C
		
	
	
	
	
	
| // SPDX-License-Identifier: GPL-2.0
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| /*
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|  * Special driver to handle of-platdata
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|  *
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|  * Copyright 2019 Google LLC
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|  *
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|  * Some code from coreboot lpss.c
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|  */
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| 
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| #include <common.h>
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| #include <dm.h>
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| #include <pci.h>
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| #include <asm/io.h>
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| #include <asm/lpss.h>
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| 
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| enum {
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| 	LPSS_RESET_CTL_REG	= 0x204,
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| 
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| 	/*
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| 	 * Bit 1:0 controls LPSS controller reset.
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| 	 *
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| 	 * 00 ->LPSS Host Controller is in reset (Reset Asserted)
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| 	 * 01/10 ->Reserved
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| 	 * 11 ->LPSS Host Controller is NOT at reset (Reset Released)
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| 	 */
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| 	LPSS_CNT_RST_RELEASE	= 3,
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| 
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| 	/* Power management control and status register */
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| 	PME_CTRL_STATUS		= 0x84,
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| 
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| 	/* Bit 1:0 Powerstate, controls D0 and D3 state */
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| 	POWER_STATE_MASK	= 3,
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| };
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| 
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| /* Take controller out of reset */
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| void lpss_reset_release(void *regs)
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| {
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| 	writel(LPSS_CNT_RST_RELEASE, regs + LPSS_RESET_CTL_REG);
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| }
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| 
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| void lpss_set_power_state(struct udevice *dev, enum lpss_pwr_state state)
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| {
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| 	dm_pci_clrset_config8(dev, PME_CTRL_STATUS, POWER_STATE_MASK, state);
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| }
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