minix/kernel/arch/earm/include/cpufunc.h

#ifndef _ARM_CPUFUNC_H
#define _ARM_CPUFUNC_H

#if 0
/* check interrupt state */
static inline void check_int(unsigned int state, int line)
{
	unsigned int cpsr = 0;

	asm volatile("mrs %0, cpsr" : "=r" (cpsr));

	if ((cpsr & PSR_F) != (state & PSR_F))
	    printf("%d: FIQs are unexpectedly %s\n", line, (cpsr & PSR_F) ? "MASKED" : "UNMASKED");

	if ((cpsr & PSR_I) != (state & PSR_I))
	    printf("%d: IRQs are unexpectedly %s\n", line, (cpsr & PSR_I) ? "MASKED" : "UNMASKED");

}
#endif

/* Data memory barrier */
static inline void dmb(void)
{
	asm volatile("dmb" : : : "memory");
}

/* Data synchronization barrier */
static inline void dsb(void)
{
	asm volatile("dsb" : : : "memory");
}

/* Instruction synchronization barrier */
static inline void isb(void)
{
	asm volatile("isb" : : : "memory");
}

static inline void barrier(void)
{
	dsb();
	isb();
}


/* Read CLIDR, Cache Level ID Register */
static inline u32_t read_clidr(){
	u32_t clidr;
	asm volatile("mrc p15, 1, %[clidr], c0, c0 , 1 @ READ CLIDR\n\t"
				: [clidr] "=r" (clidr));
	return clidr;
}


/* Read CSSELR, Cache Size Selection Register */
static inline u32_t read_csselr(){
	u32_t csselr;
	asm volatile("mrc p15, 2, %[csselr], c0, c0 , 0 @ READ CSSELR\n\t"
				: [csselr] "=r" (csselr));
	return csselr;
}

/* Write CSSELR, Cache Size Selection Register */
static inline void write_csselr(u32_t csselr){
	asm volatile("mcr p15, 2, %[csselr], c0, c0 , 0 @ WRITE CSSELR\n\t"
				: : [csselr] "r" (csselr));
}

/* Read Cache Size ID Register */
static inline u32_t read_ccsidr()
{
	u32_t ccsidr;
	asm volatile("mrc p15, 1, %[ccsidr], c0, c0, 0 @ Read CCSIDR\n\t"
			: [ccsidr] "=r" (ccsidr));
	return ccsidr;
}

/* Read TLBTR, TLB Type Register */
static inline u32_t read_tlbtr()
{
	u32_t tlbtr;
	asm volatile("mrc p15, 0, %[tlbtr], c0, c0, 3 @ Read TLBTR\n\t"
			: [tlbtr] "=r" (tlbtr));
	return tlbtr;
}

/* keesj:move these out */
static inline u32_t ilog2(u32_t t)
{
	u32_t counter =0;
	while( (t = t >> 1) ) counter ++;
	return counter;
}

/* keesj:move these out */
static inline u32_t ipow2(u32_t t)
{
	return 1 << t;
}

/*
 * type = 1 == CLEAN
 * type = 2 == INVALIDATE
 */
static inline void dcache_maint(int type){
	u32_t cache_level ;
	u32_t clidr;
	u32_t ctype;
	u32_t  ccsidr;
	u32_t  line_size,line_length;
	u32_t  number_of_sets,number_of_ways;
	u32_t  set,way;

	clidr = read_clidr();
	u32_t loc =  ( clidr >> 24) & 0x7;
	u32_t louu =  ( clidr >> 27) & 0x7;
	u32_t louis =  ( clidr >> 21) & 0x7;
	for (cache_level =0 ; cache_level < loc; cache_level++){
		/* get current cache type */
		ctype = ( clidr >> cache_level*3) & 0x7;
		/* select data or unified or cache level */
		write_csselr(cache_level << 1);
		isb();
		ccsidr = read_ccsidr();
		line_size = ccsidr & 0x7;
		line_length = 2 << (line_size + 1) ; /* 2**(line_size + 2) */
		number_of_sets = ((ccsidr >> 13) & 0x7fff) + 1;
		number_of_ways = ((ccsidr >> 3) & 0x3ff) + 1;

		u32_t way_bits = ilog2(number_of_ways);
		if(ipow2(ilog2(number_of_ways) < number_of_ways) ) {
			way_bits++;
		}

		u32_t l = ilog2(line_length);
		for (way =0 ; way < number_of_ways; way++) {
			for (set =0 ; set < number_of_sets; set++) {
				u32_t val = ( way << (32 - way_bits) ) |  (set << l) | (cache_level << 1 );
				if (type == 1) {
					/* DCCISW, Data Cache Clean and Invalidate by Set/Way */
					asm volatile("mcr p15, 0, %[set], c7, c14, 2 @ DCCISW" 
							: : [set] "r" (val));
				} else if (type ==2 ){
					/* DCISW, Data Cache Invalidate by Set/Way */
					asm volatile("mcr p15, 0, %[set], c7, c6, 2" 
							: : [set] "r" (val)); 
				}
			}
		}
	}
	dsb();
	isb();

}
static inline void dcache_clean(){
	dcache_maint(1);
}
static inline void dcache_invalidate (){
	dcache_maint(2);
}

static inline void refresh_tlb(void)
{
	dsb();

	/* Invalidate entire unified TLB */
	asm volatile("mcr p15, 0, %[zero], c8, c7, 0 @ TLBIALL\n\t" : : [zero] "r" (0));

#if 0
	/* Invalidate entire data TLB */
	asm volatile("mcr p15, 0, %[zero], c8, c6, 0" : : [zero] "r" (0));

	/* Invalidate entire instruction TLB */
	asm volatile("mcr p15, 0, %[zero], c8, c5, 0" : : [zero] "r" (0));
#endif

	/*
	 * Invalidate all instruction caches to PoU.
	 * Also flushes branch target cache.
	 */
	asm volatile("mcr p15, 0, %[zero], c7, c5, 0" : : [zero] "r" (0));

	/* Invalidate entire branch predictor array */
	asm volatile("mcr p15, 0, %[zero], c7, c5, 6" : : [zero] "r" (0)); /* flush BTB */

	dsb();
	isb();
}


/* Read System Control Register */
static inline u32_t read_sctlr()
{
	u32_t ctl;

	asm volatile("mrc p15, 0, %[ctl], c1, c0, 0 @ Read SCTLR\n\t"
			: [ctl] "=r" (ctl));

	return ctl;
}

/* Write System Control Register */
static inline void write_sctlr(u32_t ctl)
{
	asm volatile("mcr p15, 0, %[ctl], c1, c0, 0 @ Write SCTLR\n\t"
			: : [ctl] "r" (ctl));
	isb();
}

/* Read Translation Table Base Register 0 */
static inline u32_t read_ttbr0()
{
	u32_t bar;

	asm volatile("mrc p15, 0, %[bar], c2, c0, 0 @ Read TTBR0\n\t"
			: [bar] "=r" (bar));

	return bar;
}

/* Write Translation Table Base Register 0 */
static inline void write_ttbr0(u32_t bar)
{
	barrier();

	asm volatile("mcr p15, 0, %[bar], c2, c0, 0 @ Write TTBR0\n\t"
			: : [bar] "r" (bar));

	refresh_tlb();
}

/* Reload Translation Table Base Register 0 */
static inline void reload_ttbr0(void)
{
	reg_t ttbr = read_ttbr0();
	write_ttbr0(ttbr);
}

/* Read Translation Table Base Register 1 */
static inline u32_t read_ttbr1()
{
	u32_t bar;

	asm volatile("mrc p15, 0, %[bar], c2, c0, 1 @ Read TTBR1\n\t"
			: [bar] "=r" (bar));

	return bar;
}

/* Write Translation Table Base Register 1 */
static inline void write_ttbr1(u32_t bar)
{
	barrier();

	asm volatile("mcr p15, 0, %[bar], c2, c0, 1 @ Write TTBR1\n\t"
			: : [bar] "r" (bar));

	refresh_tlb();
}

/* Reload Translation Table Base Register 1 */
static inline void reload_ttbr1(void)
{
	reg_t ttbr = read_ttbr1();

	write_ttbr1(ttbr);
}

/* Read Translation Table Base Control Register */
static inline u32_t read_ttbcr()
{
	u32_t bcr;

	asm volatile("mrc p15, 0, %[bcr], c2, c0, 2 @ Read TTBCR\n\t"
			: [bcr] "=r" (bcr));

	return bcr;
}

/* Write Translation Table Base Control Register */
static inline void write_ttbcr(u32_t bcr)
{
	asm volatile("mcr p15, 0, %[bcr], c2, c0, 2 @ Write TTBCR\n\t"
			: : [bcr] "r" (bcr));

	isb();
}

/* Read Domain Access Control Register */
static inline u32_t read_dacr()
{
	u32_t dacr;

	asm volatile("mrc p15, 0, %[dacr], c3, c0, 0 @ Read DACR\n\t"
			: [dacr] "=r" (dacr));

	return dacr;
}

/* Write Domain Access Control Register */
static inline void write_dacr(u32_t dacr)
{
	asm volatile("mcr p15, 0, %[dacr], c3, c0, 0 @ Write DACR\n\t"
			: : [dacr] "r" (dacr));

	isb();
}

/* Read Data Fault Status Register */
static inline u32_t read_dfsr()
{
	u32_t fsr;

	asm volatile("mrc p15, 0, %[fsr], c5, c0, 0 @ Read DFSR\n\t"
			: [fsr] "=r" (fsr));

	return fsr;
}

/* Write Data Fault Status Register */
static inline void write_dfsr(u32_t fsr)
{
	asm volatile("mcr p15, 0, %[fsr], c5, c0, 0 @ Write DFSR\n\t"
			: : [fsr] "r" (fsr));

	isb();
}

/* Read Instruction Fault Status Register */
static inline u32_t read_ifsr()
{
	u32_t fsr;

	asm volatile("mrc p15, 0, %[fsr], c5, c0, 1 @ Read IFSR\n\t"
			: [fsr] "=r" (fsr));

	return fsr;
}

/* Write Instruction Fault Status Register */
static inline void write_ifsr(u32_t fsr)
{
	asm volatile("mcr p15, 0, %[fsr], c5, c0, 1 @ Write IFSR\n\t"
			: : [fsr] "r" (fsr));

	isb();
}

/* Read Data Fault Address Register */
static inline u32_t read_dfar()
{
	u32_t far;

	asm volatile("mrc p15, 0, %[far], c6, c0, 0 @ Read DFAR\n\t"
			: [far] "=r" (far));

	return far;
}

/* Write Data Fault Address Register */
static inline void write_dfar(u32_t far)
{
	asm volatile("mcr p15, 0, %[far], c6, c0, 0 @ Write DFAR\n\t"
			: : [far] "r" (far));

	isb();
}

/* Read Instruction Fault Address Register */
static inline u32_t read_ifar()
{
	u32_t far;

	asm volatile("mrc p15, 0, %[far], c6, c0, 2 @ Read IFAR\n\t"
			: [far] "=r" (far));

	return far;
}

/* Write Instruction Fault Address Register */
static inline void write_ifar(u32_t far)
{
	asm volatile("mcr p15, 0, %[far], c6, c0, 2 @ Write IFAR\n\t"
			: : [far] "r" (far));

	isb();
}

/* Read Vector Base Address Register */
static inline u32_t read_vbar()
{
	u32_t vbar;

	asm volatile("mrc p15, 0, %[vbar], c12, c0, 0 @ Read VBAR\n\t"
			: [vbar] "=r" (vbar));

	return vbar;
}

/* Write Vector Base Address Register */
static inline void write_vbar(u32_t vbar)
{
	asm volatile("mcr p15, 0, %[vbar], c12, c0, 0 @ Write VBAR\n\t"
			: : [vbar] "r" (vbar));

	isb();
}

/* Read the Main ID Register  */
static inline u32_t read_midr()
{
	u32_t id;

	asm volatile("mrc p15, 0, %[id], c0, c0, 0 @ read MIDR\n\t"
			: [id] "=r" (id));

	return id;
}

/* Read Auxiliary Control Register */
static inline u32_t read_actlr()
{
	u32_t ctl;

	asm volatile("mrc p15, 0, %[ctl], c1, c0, 1 @ Read ACTLR\n\t"
			: [ctl] "=r" (ctl));

	return ctl;
}

/* Write Auxiliary Control Register */
static inline void write_actlr(u32_t ctl)
{
//http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.ddi0344k/Babjbjbb.html
	asm volatile("mcr p15, 0, %[ctl], c1, c0, 1 @ Write ACTLR\n\t"
			: : [ctl] "r" (ctl));

	isb();
}

/* Read Current Program Status Register */
static inline u32_t read_cpsr()
{
	u32_t status;

	asm volatile("mrs %[status], cpsr @ read CPSR"
			: [status] "=r" (status));

	return status;
}

/* Write Current Program Status Register */
static inline void write_cpsr(u32_t status)
{
	asm volatile("msr cpsr_c, %[status] @ write CPSR"
			: : [status] "r" (status));
}

#endif /* _ARM_CPUFUNC_H */