smt_snooze_delay was designed to delay idle loop's nap entry in the native idle code before it got ported over to use as part of the cpuidle framework. A -ve value assigned to smt_snooze_delay should result in busy looping, in other words disabling the entry to nap state. - https://lists.ozlabs.org/pipermail/linuxppc-dev/2010-May/082450.html This particular functionality can be achieved currently by echo 1 > /sys/devices/system/cpu/cpu*/state1/disable but it is broken when one assigns -ve value to the smt_snooze_delay variable either via sysfs entry or ppc64_cpu util. This patch aims to fix this, by disabling nap state when smt_snooze_delay variable is set to -ve value. Signed-off-by: Deepthi Dharwar <deepthi@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
		
			
				
	
	
		
			417 lines
		
	
	
	
		
			12 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			417 lines
		
	
	
	
		
			12 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
#ifndef _ASM_POWERPC_PROCESSOR_H
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#define _ASM_POWERPC_PROCESSOR_H
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/*
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 * Copyright (C) 2001 PPC 64 Team, IBM Corp
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 *
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 * This program is free software; you can redistribute it and/or
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 * modify it under the terms of the GNU General Public License
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 * as published by the Free Software Foundation; either version
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 * 2 of the License, or (at your option) any later version.
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 */
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#include <asm/reg.h>
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#ifdef CONFIG_VSX
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#define TS_FPRWIDTH 2
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#else
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#define TS_FPRWIDTH 1
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#endif
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#ifndef __ASSEMBLY__
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#include <linux/compiler.h>
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#include <linux/cache.h>
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#include <asm/ptrace.h>
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#include <asm/types.h>
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/* We do _not_ want to define new machine types at all, those must die
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 * in favor of using the device-tree
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 * -- BenH.
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 */
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/* PREP sub-platform types see residual.h for these */
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#define _PREP_Motorola	0x01	/* motorola prep */
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#define _PREP_Firm	0x02	/* firmworks prep */
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#define _PREP_IBM	0x00	/* ibm prep */
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#define _PREP_Bull	0x03	/* bull prep */
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/* CHRP sub-platform types. These are arbitrary */
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#define _CHRP_Motorola	0x04	/* motorola chrp, the cobra */
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#define _CHRP_IBM	0x05	/* IBM chrp, the longtrail and longtrail 2 */
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#define _CHRP_Pegasos	0x06	/* Genesi/bplan's Pegasos and Pegasos2 */
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#define _CHRP_briq	0x07	/* TotalImpact's briQ */
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#if defined(__KERNEL__) && defined(CONFIG_PPC32)
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extern int _chrp_type;
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#ifdef CONFIG_PPC_PREP
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/* what kind of prep workstation we are */
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extern int _prep_type;
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#endif /* CONFIG_PPC_PREP */
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#endif /* defined(__KERNEL__) && defined(CONFIG_PPC32) */
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/*
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 * Default implementation of macro that returns current
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 * instruction pointer ("program counter").
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 */
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#define current_text_addr() ({ __label__ _l; _l: &&_l;})
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/* Macros for adjusting thread priority (hardware multi-threading) */
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#define HMT_very_low()   asm volatile("or 31,31,31   # very low priority")
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#define HMT_low()	 asm volatile("or 1,1,1	     # low priority")
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#define HMT_medium_low() asm volatile("or 6,6,6      # medium low priority")
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#define HMT_medium()	 asm volatile("or 2,2,2	     # medium priority")
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#define HMT_medium_high() asm volatile("or 5,5,5      # medium high priority")
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#define HMT_high()	 asm volatile("or 3,3,3	     # high priority")
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#ifdef __KERNEL__
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struct task_struct;
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void start_thread(struct pt_regs *regs, unsigned long fdptr, unsigned long sp);
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void release_thread(struct task_struct *);
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/* Lazy FPU handling on uni-processor */
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extern struct task_struct *last_task_used_math;
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extern struct task_struct *last_task_used_altivec;
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extern struct task_struct *last_task_used_vsx;
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extern struct task_struct *last_task_used_spe;
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#ifdef CONFIG_PPC32
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#if CONFIG_TASK_SIZE > CONFIG_KERNEL_START
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#error User TASK_SIZE overlaps with KERNEL_START address
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#endif
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#define TASK_SIZE	(CONFIG_TASK_SIZE)
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/* This decides where the kernel will search for a free chunk of vm
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 * space during mmap's.
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 */
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#define TASK_UNMAPPED_BASE	(TASK_SIZE / 8 * 3)
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#endif
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#ifdef CONFIG_PPC64
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/* 64-bit user address space is 46-bits (64TB user VM) */
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#define TASK_SIZE_USER64 (0x0000400000000000UL)
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/* 
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 * 32-bit user address space is 4GB - 1 page 
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 * (this 1 page is needed so referencing of 0xFFFFFFFF generates EFAULT
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 */
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#define TASK_SIZE_USER32 (0x0000000100000000UL - (1*PAGE_SIZE))
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#define TASK_SIZE_OF(tsk) (test_tsk_thread_flag(tsk, TIF_32BIT) ? \
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		TASK_SIZE_USER32 : TASK_SIZE_USER64)
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#define TASK_SIZE	  TASK_SIZE_OF(current)
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/* This decides where the kernel will search for a free chunk of vm
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 * space during mmap's.
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 */
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#define TASK_UNMAPPED_BASE_USER32 (PAGE_ALIGN(TASK_SIZE_USER32 / 4))
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#define TASK_UNMAPPED_BASE_USER64 (PAGE_ALIGN(TASK_SIZE_USER64 / 4))
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#define TASK_UNMAPPED_BASE ((is_32bit_task()) ? \
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		TASK_UNMAPPED_BASE_USER32 : TASK_UNMAPPED_BASE_USER64 )
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#endif
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#ifdef __powerpc64__
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#define STACK_TOP_USER64 TASK_SIZE_USER64
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#define STACK_TOP_USER32 TASK_SIZE_USER32
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#define STACK_TOP (is_32bit_task() ? \
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		   STACK_TOP_USER32 : STACK_TOP_USER64)
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#define STACK_TOP_MAX STACK_TOP_USER64
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#else /* __powerpc64__ */
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#define STACK_TOP TASK_SIZE
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#define STACK_TOP_MAX	STACK_TOP
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#endif /* __powerpc64__ */
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typedef struct {
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	unsigned long seg;
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} mm_segment_t;
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#define TS_FPROFFSET 0
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#define TS_VSRLOWOFFSET 1
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#define TS_FPR(i) fpr[i][TS_FPROFFSET]
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struct thread_struct {
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	unsigned long	ksp;		/* Kernel stack pointer */
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	unsigned long	ksp_limit;	/* if ksp <= ksp_limit stack overflow */
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#ifdef CONFIG_PPC64
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	unsigned long	ksp_vsid;
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#endif
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	struct pt_regs	*regs;		/* Pointer to saved register state */
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	mm_segment_t	fs;		/* for get_fs() validation */
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#ifdef CONFIG_BOOKE
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	/* BookE base exception scratch space; align on cacheline */
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	unsigned long	normsave[8] ____cacheline_aligned;
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#endif
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#ifdef CONFIG_PPC32
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	void		*pgdir;		/* root of page-table tree */
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#endif
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#ifdef CONFIG_PPC_ADV_DEBUG_REGS
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	/*
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	 * The following help to manage the use of Debug Control Registers
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	 * om the BookE platforms.
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	 */
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	unsigned long	dbcr0;
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	unsigned long	dbcr1;
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#ifdef CONFIG_BOOKE
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	unsigned long	dbcr2;
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#endif
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	/*
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	 * The stored value of the DBSR register will be the value at the
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	 * last debug interrupt. This register can only be read from the
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	 * user (will never be written to) and has value while helping to
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	 * describe the reason for the last debug trap.  Torez
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	 */
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	unsigned long	dbsr;
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	/*
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	 * The following will contain addresses used by debug applications
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	 * to help trace and trap on particular address locations.
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	 * The bits in the Debug Control Registers above help define which
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	 * of the following registers will contain valid data and/or addresses.
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	 */
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	unsigned long	iac1;
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	unsigned long	iac2;
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#if CONFIG_PPC_ADV_DEBUG_IACS > 2
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	unsigned long	iac3;
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	unsigned long	iac4;
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#endif
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	unsigned long	dac1;
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	unsigned long	dac2;
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#if CONFIG_PPC_ADV_DEBUG_DVCS > 0
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	unsigned long	dvc1;
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	unsigned long	dvc2;
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#endif
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#endif
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	/* FP and VSX 0-31 register set */
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	double		fpr[32][TS_FPRWIDTH];
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	struct {
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		unsigned int pad;
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		unsigned int val;	/* Floating point status */
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	} fpscr;
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	int		fpexc_mode;	/* floating-point exception mode */
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	unsigned int	align_ctl;	/* alignment handling control */
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#ifdef CONFIG_PPC64
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	unsigned long	start_tb;	/* Start purr when proc switched in */
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	unsigned long	accum_tb;	/* Total accumilated purr for process */
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#ifdef CONFIG_HAVE_HW_BREAKPOINT
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	struct perf_event *ptrace_bps[HBP_NUM];
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	/*
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	 * Helps identify source of single-step exception and subsequent
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	 * hw-breakpoint enablement
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	 */
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	struct perf_event *last_hit_ubp;
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#endif /* CONFIG_HAVE_HW_BREAKPOINT */
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#endif
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	unsigned long	dabr;		/* Data address breakpoint register */
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	unsigned long	dabrx;		/*      ... extension  */
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	unsigned long	trap_nr;	/* last trap # on this thread */
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#ifdef CONFIG_ALTIVEC
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	/* Complete AltiVec register set */
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	vector128	vr[32] __attribute__((aligned(16)));
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	/* AltiVec status */
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	vector128	vscr __attribute__((aligned(16)));
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	unsigned long	vrsave;
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	int		used_vr;	/* set if process has used altivec */
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#endif /* CONFIG_ALTIVEC */
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#ifdef CONFIG_VSX
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	/* VSR status */
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	int		used_vsr;	/* set if process has used altivec */
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#endif /* CONFIG_VSX */
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#ifdef CONFIG_SPE
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	unsigned long	evr[32];	/* upper 32-bits of SPE regs */
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	u64		acc;		/* Accumulator */
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	unsigned long	spefscr;	/* SPE & eFP status */
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	int		used_spe;	/* set if process has used spe */
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#endif /* CONFIG_SPE */
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#ifdef CONFIG_KVM_BOOK3S_32_HANDLER
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	void*		kvm_shadow_vcpu; /* KVM internal data */
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#endif /* CONFIG_KVM_BOOK3S_32_HANDLER */
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#if defined(CONFIG_KVM) && defined(CONFIG_BOOKE)
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	struct kvm_vcpu	*kvm_vcpu;
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#endif
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#ifdef CONFIG_PPC64
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	unsigned long	dscr;
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	int		dscr_inherit;
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#endif
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};
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#define ARCH_MIN_TASKALIGN 16
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#define INIT_SP		(sizeof(init_stack) + (unsigned long) &init_stack)
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#define INIT_SP_LIMIT \
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	(_ALIGN_UP(sizeof(init_thread_info), 16) + (unsigned long) &init_stack)
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#ifdef CONFIG_SPE
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#define SPEFSCR_INIT .spefscr = SPEFSCR_FINVE | SPEFSCR_FDBZE | SPEFSCR_FUNFE | SPEFSCR_FOVFE,
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#else
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#define SPEFSCR_INIT
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#endif
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#ifdef CONFIG_PPC32
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#define INIT_THREAD { \
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	.ksp = INIT_SP, \
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	.ksp_limit = INIT_SP_LIMIT, \
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	.fs = KERNEL_DS, \
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	.pgdir = swapper_pg_dir, \
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	.fpexc_mode = MSR_FE0 | MSR_FE1, \
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	SPEFSCR_INIT \
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}
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#else
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#define INIT_THREAD  { \
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	.ksp = INIT_SP, \
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	.ksp_limit = INIT_SP_LIMIT, \
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	.regs = (struct pt_regs *)INIT_SP - 1, /* XXX bogus, I think */ \
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	.fs = KERNEL_DS, \
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	.fpr = {{0}}, \
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	.fpscr = { .val = 0, }, \
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	.fpexc_mode = 0, \
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}
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#endif
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/*
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 * Return saved PC of a blocked thread. For now, this is the "user" PC
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 */
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#define thread_saved_pc(tsk)    \
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        ((tsk)->thread.regs? (tsk)->thread.regs->nip: 0)
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#define task_pt_regs(tsk)	((struct pt_regs *)(tsk)->thread.regs)
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unsigned long get_wchan(struct task_struct *p);
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#define KSTK_EIP(tsk)  ((tsk)->thread.regs? (tsk)->thread.regs->nip: 0)
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#define KSTK_ESP(tsk)  ((tsk)->thread.regs? (tsk)->thread.regs->gpr[1]: 0)
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/* Get/set floating-point exception mode */
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#define GET_FPEXC_CTL(tsk, adr) get_fpexc_mode((tsk), (adr))
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#define SET_FPEXC_CTL(tsk, val) set_fpexc_mode((tsk), (val))
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extern int get_fpexc_mode(struct task_struct *tsk, unsigned long adr);
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extern int set_fpexc_mode(struct task_struct *tsk, unsigned int val);
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#define GET_ENDIAN(tsk, adr) get_endian((tsk), (adr))
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#define SET_ENDIAN(tsk, val) set_endian((tsk), (val))
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extern int get_endian(struct task_struct *tsk, unsigned long adr);
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extern int set_endian(struct task_struct *tsk, unsigned int val);
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#define GET_UNALIGN_CTL(tsk, adr)	get_unalign_ctl((tsk), (adr))
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#define SET_UNALIGN_CTL(tsk, val)	set_unalign_ctl((tsk), (val))
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extern int get_unalign_ctl(struct task_struct *tsk, unsigned long adr);
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extern int set_unalign_ctl(struct task_struct *tsk, unsigned int val);
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static inline unsigned int __unpack_fe01(unsigned long msr_bits)
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{
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	return ((msr_bits & MSR_FE0) >> 10) | ((msr_bits & MSR_FE1) >> 8);
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}
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static inline unsigned long __pack_fe01(unsigned int fpmode)
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{
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	return ((fpmode << 10) & MSR_FE0) | ((fpmode << 8) & MSR_FE1);
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}
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#ifdef CONFIG_PPC64
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#define cpu_relax()	do { HMT_low(); HMT_medium(); barrier(); } while (0)
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#else
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#define cpu_relax()	barrier()
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#endif
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/* Check that a certain kernel stack pointer is valid in task_struct p */
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int validate_sp(unsigned long sp, struct task_struct *p,
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                       unsigned long nbytes);
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/*
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 * Prefetch macros.
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 */
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#define ARCH_HAS_PREFETCH
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#define ARCH_HAS_PREFETCHW
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#define ARCH_HAS_SPINLOCK_PREFETCH
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static inline void prefetch(const void *x)
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{
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	if (unlikely(!x))
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		return;
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	__asm__ __volatile__ ("dcbt 0,%0" : : "r" (x));
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}
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static inline void prefetchw(const void *x)
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{
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	if (unlikely(!x))
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		return;
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	__asm__ __volatile__ ("dcbtst 0,%0" : : "r" (x));
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}
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#define spin_lock_prefetch(x)	prefetchw(x)
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#ifdef CONFIG_PPC64
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#define HAVE_ARCH_PICK_MMAP_LAYOUT
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#endif
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#ifdef CONFIG_PPC64
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static inline unsigned long get_clean_sp(struct pt_regs *regs, int is_32)
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{
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	unsigned long sp;
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	if (is_32)
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		sp = regs->gpr[1] & 0x0ffffffffUL;
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	else
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		sp = regs->gpr[1];
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	return sp;
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}
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#else
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static inline unsigned long get_clean_sp(struct pt_regs *regs, int is_32)
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{
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	return regs->gpr[1];
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}
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#endif
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 | 
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extern unsigned long cpuidle_disable;
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enum idle_boot_override {IDLE_NO_OVERRIDE = 0, IDLE_POWERSAVE_OFF};
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						|
 | 
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extern int powersave_nap;	/* set if nap mode can be used in idle loop */
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extern void power7_nap(void);
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						|
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#ifdef CONFIG_PSERIES_IDLE
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						|
extern void update_smt_snooze_delay(int cpu, int residency);
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						|
#else
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static inline void update_smt_snooze_delay(int cpu, int residency) {}
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#endif
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						|
 | 
						|
extern void flush_instruction_cache(void);
 | 
						|
extern void hard_reset_now(void);
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						|
extern void poweroff_now(void);
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						|
extern int fix_alignment(struct pt_regs *);
 | 
						|
extern void cvt_fd(float *from, double *to);
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						|
extern void cvt_df(double *from, float *to);
 | 
						|
extern void _nmask_and_or_msr(unsigned long nmask, unsigned long or_val);
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						|
 | 
						|
#ifdef CONFIG_PPC64
 | 
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/*
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						|
 * We handle most unaligned accesses in hardware. On the other hand 
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						|
 * unaligned DMA can be very expensive on some ppc64 IO chips (it does
 | 
						|
 * powers of 2 writes until it reaches sufficient alignment).
 | 
						|
 *
 | 
						|
 * Based on this we disable the IP header alignment in network drivers.
 | 
						|
 */
 | 
						|
#define NET_IP_ALIGN	0
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						|
#endif
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						|
 | 
						|
#endif /* __KERNEL__ */
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						|
#endif /* __ASSEMBLY__ */
 | 
						|
#endif /* _ASM_POWERPC_PROCESSOR_H */
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