80 lines
		
	
	
	
		
			1.9 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			80 lines
		
	
	
	
		
			1.9 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * Copyright (C) 2013 Imagination Technologies
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|  * Author: Paul Burton <paul.burton@imgtec.com>
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|  *
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|  * This program is free software; you can redistribute it and/or modify it
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|  * under the terms of the GNU General Public License as published by the
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|  * Free Software Foundation;  either version 2 of the  License, or (at your
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|  * option) any later version.
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|  */
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| 
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| #include <linux/errno.h>
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| #include <linux/percpu.h>
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| #include <linux/spinlock.h>
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| 
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| #include <asm/mips-cm.h>
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| #include <asm/mips-cpc.h>
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| 
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| void __iomem *mips_cpc_base;
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| 
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| static DEFINE_PER_CPU_ALIGNED(spinlock_t, cpc_core_lock);
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| 
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| static DEFINE_PER_CPU_ALIGNED(unsigned long, cpc_core_lock_flags);
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| 
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| phys_addr_t __weak mips_cpc_phys_base(void)
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| {
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| 	u32 cpc_base;
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| 
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| 	if (!mips_cm_present())
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| 		return 0;
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| 
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| 	if (!(read_gcr_cpc_status() & CM_GCR_CPC_STATUS_EX_MSK))
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| 		return 0;
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| 
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| 	/* If the CPC is already enabled, leave it so */
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| 	cpc_base = read_gcr_cpc_base();
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| 	if (cpc_base & CM_GCR_CPC_BASE_CPCEN_MSK)
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| 		return cpc_base & CM_GCR_CPC_BASE_CPCBASE_MSK;
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| 
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| 	/* Otherwise, give it the default address & enable it */
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| 	cpc_base = mips_cpc_default_phys_base();
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| 	write_gcr_cpc_base(cpc_base | CM_GCR_CPC_BASE_CPCEN_MSK);
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| 	return cpc_base;
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| }
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| 
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| int mips_cpc_probe(void)
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| {
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| 	phys_addr_t addr;
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| 	unsigned cpu;
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| 
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| 	for_each_possible_cpu(cpu)
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| 		spin_lock_init(&per_cpu(cpc_core_lock, cpu));
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| 
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| 	addr = mips_cpc_phys_base();
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| 	if (!addr)
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| 		return -ENODEV;
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| 
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| 	mips_cpc_base = ioremap_nocache(addr, 0x8000);
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| 	if (!mips_cpc_base)
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| 		return -ENXIO;
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| 
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| 	return 0;
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| }
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| 
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| void mips_cpc_lock_other(unsigned int core)
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| {
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| 	unsigned curr_core;
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| 	preempt_disable();
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| 	curr_core = current_cpu_data.core;
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| 	spin_lock_irqsave(&per_cpu(cpc_core_lock, curr_core),
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| 			  per_cpu(cpc_core_lock_flags, curr_core));
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| 	write_cpc_cl_other(core << CPC_Cx_OTHER_CORENUM_SHF);
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| }
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| 
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| void mips_cpc_unlock_other(void)
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| {
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| 	unsigned curr_core = current_cpu_data.core;
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| 	spin_unlock_irqrestore(&per_cpu(cpc_core_lock, curr_core),
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| 			       per_cpu(cpc_core_lock_flags, curr_core));
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| 	preempt_enable();
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| }
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