Home | History | Annotate | Download | only in asm-arm
      1 /*
      2  *  linux/include/asm-arm/tlbflush.h
      3  *
      4  *  Copyright (C) 1999-2003 Russell King
      5  *
      6  * This program is free software; you can redistribute it and/or modify
      7  * it under the terms of the GNU General Public License version 2 as
      8  * published by the Free Software Foundation.
      9  */
     10 #ifndef _ASMARM_TLBFLUSH_H
     11 #define _ASMARM_TLBFLUSH_H
     12 
     13 
     14 #ifndef CONFIG_MMU
     15 
     16 #define tlb_flush(tlb)	((void) tlb)
     17 
     18 #else /* CONFIG_MMU */
     19 
     20 #include <asm/glue.h>
     21 
     22 #define TLB_V3_PAGE	(1 << 0)
     23 #define TLB_V4_U_PAGE	(1 << 1)
     24 #define TLB_V4_D_PAGE	(1 << 2)
     25 #define TLB_V4_I_PAGE	(1 << 3)
     26 #define TLB_V6_U_PAGE	(1 << 4)
     27 #define TLB_V6_D_PAGE	(1 << 5)
     28 #define TLB_V6_I_PAGE	(1 << 6)
     29 
     30 #define TLB_V3_FULL	(1 << 8)
     31 #define TLB_V4_U_FULL	(1 << 9)
     32 #define TLB_V4_D_FULL	(1 << 10)
     33 #define TLB_V4_I_FULL	(1 << 11)
     34 #define TLB_V6_U_FULL	(1 << 12)
     35 #define TLB_V6_D_FULL	(1 << 13)
     36 #define TLB_V6_I_FULL	(1 << 14)
     37 
     38 #define TLB_V6_U_ASID	(1 << 16)
     39 #define TLB_V6_D_ASID	(1 << 17)
     40 #define TLB_V6_I_ASID	(1 << 18)
     41 
     42 #define TLB_DCLEAN	(1 << 30)
     43 #define TLB_WB		(1 << 31)
     44 
     45 /*
     46  *	MMU TLB Model
     47  *	=============
     48  *
     49  *	We have the following to choose from:
     50  *	  v3    - ARMv3
     51  *	  v4    - ARMv4 without write buffer
     52  *	  v4wb  - ARMv4 with write buffer without I TLB flush entry instruction
     53  *	  v4wbi - ARMv4 with write buffer with I TLB flush entry instruction
     54  *	  v6wbi - ARMv6 with write buffer with I TLB flush entry instruction
     55  */
     56 #undef _TLB
     57 #undef MULTI_TLB
     58 
     59 #define v3_tlb_flags	(TLB_V3_FULL | TLB_V3_PAGE)
     60 
     61 #ifdef CONFIG_CPU_TLB_V3
     62 # define v3_possible_flags	v3_tlb_flags
     63 # define v3_always_flags	v3_tlb_flags
     64 # ifdef _TLB
     65 #  define MULTI_TLB 1
     66 # else
     67 #  define _TLB v3
     68 # endif
     69 #else
     70 # define v3_possible_flags	0
     71 # define v3_always_flags	(-1UL)
     72 #endif
     73 
     74 #define v4_tlb_flags	(TLB_V4_U_FULL | TLB_V4_U_PAGE)
     75 
     76 #ifdef CONFIG_CPU_TLB_V4WT
     77 # define v4_possible_flags	v4_tlb_flags
     78 # define v4_always_flags	v4_tlb_flags
     79 # ifdef _TLB
     80 #  define MULTI_TLB 1
     81 # else
     82 #  define _TLB v4
     83 # endif
     84 #else
     85 # define v4_possible_flags	0
     86 # define v4_always_flags	(-1UL)
     87 #endif
     88 
     89 #define v4wbi_tlb_flags	(TLB_WB | TLB_DCLEAN | \
     90 			 TLB_V4_I_FULL | TLB_V4_D_FULL | \
     91 			 TLB_V4_I_PAGE | TLB_V4_D_PAGE)
     92 
     93 #ifdef CONFIG_CPU_TLB_V4WBI
     94 # define v4wbi_possible_flags	v4wbi_tlb_flags
     95 # define v4wbi_always_flags	v4wbi_tlb_flags
     96 # ifdef _TLB
     97 #  define MULTI_TLB 1
     98 # else
     99 #  define _TLB v4wbi
    100 # endif
    101 #else
    102 # define v4wbi_possible_flags	0
    103 # define v4wbi_always_flags	(-1UL)
    104 #endif
    105 
    106 #define v4wb_tlb_flags	(TLB_WB | TLB_DCLEAN | \
    107 			 TLB_V4_I_FULL | TLB_V4_D_FULL | \
    108 			 TLB_V4_D_PAGE)
    109 
    110 #ifdef CONFIG_CPU_TLB_V4WB
    111 # define v4wb_possible_flags	v4wb_tlb_flags
    112 # define v4wb_always_flags	v4wb_tlb_flags
    113 # ifdef _TLB
    114 #  define MULTI_TLB 1
    115 # else
    116 #  define _TLB v4wb
    117 # endif
    118 #else
    119 # define v4wb_possible_flags	0
    120 # define v4wb_always_flags	(-1UL)
    121 #endif
    122 
    123 #define v6wbi_tlb_flags (TLB_WB | TLB_DCLEAN | \
    124 			 TLB_V6_I_FULL | TLB_V6_D_FULL | \
    125 			 TLB_V6_I_PAGE | TLB_V6_D_PAGE | \
    126 			 TLB_V6_I_ASID | TLB_V6_D_ASID)
    127 
    128 #ifdef CONFIG_CPU_TLB_V6
    129 # define v6wbi_possible_flags	v6wbi_tlb_flags
    130 # define v6wbi_always_flags	v6wbi_tlb_flags
    131 # ifdef _TLB
    132 #  define MULTI_TLB 1
    133 # else
    134 #  define _TLB v6wbi
    135 # endif
    136 #else
    137 # define v6wbi_possible_flags	0
    138 # define v6wbi_always_flags	(-1UL)
    139 #endif
    140 
    141 #ifndef _TLB
    142 #error Unknown TLB model
    143 #endif
    144 
    145 #ifndef __ASSEMBLY__
    146 
    147 struct cpu_tlb_fns {
    148 	void (*flush_user_range)(unsigned long, unsigned long, struct vm_area_struct *);
    149 	void (*flush_kern_range)(unsigned long, unsigned long);
    150 	unsigned long tlb_flags;
    151 };
    152 
    153 /*
    154  * Select the calling method
    155  */
    156 #ifdef MULTI_TLB
    157 
    158 #define __cpu_flush_user_tlb_range	cpu_tlb.flush_user_range
    159 #define __cpu_flush_kern_tlb_range	cpu_tlb.flush_kern_range
    160 
    161 #else
    162 
    163 #define __cpu_flush_user_tlb_range	__glue(_TLB,_flush_user_tlb_range)
    164 #define __cpu_flush_kern_tlb_range	__glue(_TLB,_flush_kern_tlb_range)
    165 
    166 extern void __cpu_flush_user_tlb_range(unsigned long, unsigned long, struct vm_area_struct *);
    167 extern void __cpu_flush_kern_tlb_range(unsigned long, unsigned long);
    168 
    169 #endif
    170 
    171 extern struct cpu_tlb_fns cpu_tlb;
    172 
    173 #define __cpu_tlb_flags			cpu_tlb.tlb_flags
    174 
    175 /*
    176  *	TLB Management
    177  *	==============
    178  *
    179  *	The arch/arm/mm/tlb-*.S files implement these methods.
    180  *
    181  *	The TLB specific code is expected to perform whatever tests it
    182  *	needs to determine if it should invalidate the TLB for each
    183  *	call.  Start addresses are inclusive and end addresses are
    184  *	exclusive; it is safe to round these addresses down.
    185  *
    186  *	flush_tlb_all()
    187  *
    188  *		Invalidate the entire TLB.
    189  *
    190  *	flush_tlb_mm(mm)
    191  *
    192  *		Invalidate all TLB entries in a particular address
    193  *		space.
    194  *		- mm	- mm_struct describing address space
    195  *
    196  *	flush_tlb_range(mm,start,end)
    197  *
    198  *		Invalidate a range of TLB entries in the specified
    199  *		address space.
    200  *		- mm	- mm_struct describing address space
    201  *		- start - start address (may not be aligned)
    202  *		- end	- end address (exclusive, may not be aligned)
    203  *
    204  *	flush_tlb_page(vaddr,vma)
    205  *
    206  *		Invalidate the specified page in the specified address range.
    207  *		- vaddr - virtual address (may not be aligned)
    208  *		- vma	- vma_struct describing address range
    209  *
    210  *	flush_kern_tlb_page(kaddr)
    211  *
    212  *		Invalidate the TLB entry for the specified page.  The address
    213  *		will be in the kernels virtual memory space.  Current uses
    214  *		only require the D-TLB to be invalidated.
    215  *		- kaddr - Kernel virtual memory address
    216  */
    217 
    218 /*
    219  * We optimise the code below by:
    220  *  - building a set of TLB flags that might be set in __cpu_tlb_flags
    221  *  - building a set of TLB flags that will always be set in __cpu_tlb_flags
    222  *  - if we're going to need __cpu_tlb_flags, access it once and only once
    223  *
    224  * This allows us to build optimal assembly for the single-CPU type case,
    225  * and as close to optimal given the compiler constrants for multi-CPU
    226  * case.  We could do better for the multi-CPU case if the compiler
    227  * implemented the "%?" method, but this has been discontinued due to too
    228  * many people getting it wrong.
    229  */
    230 #define possible_tlb_flags	(v3_possible_flags | \
    231 				 v4_possible_flags | \
    232 				 v4wbi_possible_flags | \
    233 				 v4wb_possible_flags | \
    234 				 v6wbi_possible_flags)
    235 
    236 #define always_tlb_flags	(v3_always_flags & \
    237 				 v4_always_flags & \
    238 				 v4wbi_always_flags & \
    239 				 v4wb_always_flags & \
    240 				 v6wbi_always_flags)
    241 
    242 #define tlb_flag(f)	((always_tlb_flags & (f)) || (__tlb_flag & possible_tlb_flags & (f)))
    243 
    244 static inline void local_flush_tlb_all(void)
    245 {
    246 	const int zero = 0;
    247 	const unsigned int __tlb_flag = __cpu_tlb_flags;
    248 
    249 	if (tlb_flag(TLB_WB))
    250 		asm("mcr%? p15, 0, %0, c7, c10, 4" : : "r" (zero));
    251 
    252 	if (tlb_flag(TLB_V3_FULL))
    253 		asm("mcr%? p15, 0, %0, c6, c0, 0" : : "r" (zero));
    254 	if (tlb_flag(TLB_V4_U_FULL | TLB_V6_U_FULL))
    255 		asm("mcr%? p15, 0, %0, c8, c7, 0" : : "r" (zero));
    256 	if (tlb_flag(TLB_V4_D_FULL | TLB_V6_D_FULL))
    257 		asm("mcr%? p15, 0, %0, c8, c6, 0" : : "r" (zero));
    258 	if (tlb_flag(TLB_V4_I_FULL | TLB_V6_I_FULL))
    259 		asm("mcr%? p15, 0, %0, c8, c5, 0" : : "r" (zero));
    260 }
    261 
    262 static inline void local_flush_tlb_mm(struct mm_struct *mm)
    263 {
    264 	const int zero = 0;
    265 	const int asid = ASID(mm);
    266 	const unsigned int __tlb_flag = __cpu_tlb_flags;
    267 
    268 	if (tlb_flag(TLB_WB))
    269 		asm("mcr%? p15, 0, %0, c7, c10, 4" : : "r" (zero));
    270 
    271 	if (cpu_isset(smp_processor_id(), mm->cpu_vm_mask)) {
    272 		if (tlb_flag(TLB_V3_FULL))
    273 			asm("mcr%? p15, 0, %0, c6, c0, 0" : : "r" (zero));
    274 		if (tlb_flag(TLB_V4_U_FULL))
    275 			asm("mcr%? p15, 0, %0, c8, c7, 0" : : "r" (zero));
    276 		if (tlb_flag(TLB_V4_D_FULL))
    277 			asm("mcr%? p15, 0, %0, c8, c6, 0" : : "r" (zero));
    278 		if (tlb_flag(TLB_V4_I_FULL))
    279 			asm("mcr%? p15, 0, %0, c8, c5, 0" : : "r" (zero));
    280 	}
    281 
    282 	if (tlb_flag(TLB_V6_U_ASID))
    283 		asm("mcr%? p15, 0, %0, c8, c7, 2" : : "r" (asid));
    284 	if (tlb_flag(TLB_V6_D_ASID))
    285 		asm("mcr%? p15, 0, %0, c8, c6, 2" : : "r" (asid));
    286 	if (tlb_flag(TLB_V6_I_ASID))
    287 		asm("mcr%? p15, 0, %0, c8, c5, 2" : : "r" (asid));
    288 }
    289 
    290 static inline void
    291 local_flush_tlb_page(struct vm_area_struct *vma, unsigned long uaddr)
    292 {
    293 	const int zero = 0;
    294 	const unsigned int __tlb_flag = __cpu_tlb_flags;
    295 
    296 	uaddr = (uaddr & PAGE_MASK) | ASID(vma->vm_mm);
    297 
    298 	if (tlb_flag(TLB_WB))
    299 		asm("mcr%? p15, 0, %0, c7, c10, 4" : : "r" (zero));
    300 
    301 	if (cpu_isset(smp_processor_id(), vma->vm_mm->cpu_vm_mask)) {
    302 		if (tlb_flag(TLB_V3_PAGE))
    303 			asm("mcr%? p15, 0, %0, c6, c0, 0" : : "r" (uaddr));
    304 		if (tlb_flag(TLB_V4_U_PAGE))
    305 			asm("mcr%? p15, 0, %0, c8, c7, 1" : : "r" (uaddr));
    306 		if (tlb_flag(TLB_V4_D_PAGE))
    307 			asm("mcr%? p15, 0, %0, c8, c6, 1" : : "r" (uaddr));
    308 		if (tlb_flag(TLB_V4_I_PAGE))
    309 			asm("mcr%? p15, 0, %0, c8, c5, 1" : : "r" (uaddr));
    310 		if (!tlb_flag(TLB_V4_I_PAGE) && tlb_flag(TLB_V4_I_FULL))
    311 			asm("mcr%? p15, 0, %0, c8, c5, 0" : : "r" (zero));
    312 	}
    313 
    314 	if (tlb_flag(TLB_V6_U_PAGE))
    315 		asm("mcr%? p15, 0, %0, c8, c7, 1" : : "r" (uaddr));
    316 	if (tlb_flag(TLB_V6_D_PAGE))
    317 		asm("mcr%? p15, 0, %0, c8, c6, 1" : : "r" (uaddr));
    318 	if (tlb_flag(TLB_V6_I_PAGE))
    319 		asm("mcr%? p15, 0, %0, c8, c5, 1" : : "r" (uaddr));
    320 }
    321 
    322 static inline void local_flush_tlb_kernel_page(unsigned long kaddr)
    323 {
    324 	const int zero = 0;
    325 	const unsigned int __tlb_flag = __cpu_tlb_flags;
    326 
    327 	kaddr &= PAGE_MASK;
    328 
    329 	if (tlb_flag(TLB_WB))
    330 		asm("mcr%? p15, 0, %0, c7, c10, 4" : : "r" (zero));
    331 
    332 	if (tlb_flag(TLB_V3_PAGE))
    333 		asm("mcr%? p15, 0, %0, c6, c0, 0" : : "r" (kaddr));
    334 	if (tlb_flag(TLB_V4_U_PAGE))
    335 		asm("mcr%? p15, 0, %0, c8, c7, 1" : : "r" (kaddr));
    336 	if (tlb_flag(TLB_V4_D_PAGE))
    337 		asm("mcr%? p15, 0, %0, c8, c6, 1" : : "r" (kaddr));
    338 	if (tlb_flag(TLB_V4_I_PAGE))
    339 		asm("mcr%? p15, 0, %0, c8, c5, 1" : : "r" (kaddr));
    340 	if (!tlb_flag(TLB_V4_I_PAGE) && tlb_flag(TLB_V4_I_FULL))
    341 		asm("mcr%? p15, 0, %0, c8, c5, 0" : : "r" (zero));
    342 
    343 	if (tlb_flag(TLB_V6_U_PAGE))
    344 		asm("mcr%? p15, 0, %0, c8, c7, 1" : : "r" (kaddr));
    345 	if (tlb_flag(TLB_V6_D_PAGE))
    346 		asm("mcr%? p15, 0, %0, c8, c6, 1" : : "r" (kaddr));
    347 	if (tlb_flag(TLB_V6_I_PAGE))
    348 		asm("mcr%? p15, 0, %0, c8, c5, 1" : : "r" (kaddr));
    349 
    350 	/* The ARM ARM states that the completion of a TLB maintenance
    351 	 * operation is only guaranteed by a DSB instruction
    352 	 */
    353 	if (tlb_flag(TLB_V6_U_PAGE | TLB_V6_D_PAGE | TLB_V6_I_PAGE))
    354 		asm("mcr%? p15, 0, %0, c7, c10, 4" : : "r" (zero));
    355 }
    356 
    357 /*
    358  *	flush_pmd_entry
    359  *
    360  *	Flush a PMD entry (word aligned, or double-word aligned) to
    361  *	RAM if the TLB for the CPU we are running on requires this.
    362  *	This is typically used when we are creating PMD entries.
    363  *
    364  *	clean_pmd_entry
    365  *
    366  *	Clean (but don't drain the write buffer) if the CPU requires
    367  *	these operations.  This is typically used when we are removing
    368  *	PMD entries.
    369  */
    370 static inline void flush_pmd_entry(pmd_t *pmd)
    371 {
    372 	const unsigned int zero = 0;
    373 	const unsigned int __tlb_flag = __cpu_tlb_flags;
    374 
    375 	if (tlb_flag(TLB_DCLEAN))
    376 		asm("mcr%?	p15, 0, %0, c7, c10, 1	@ flush_pmd"
    377 			: : "r" (pmd));
    378 	if (tlb_flag(TLB_WB))
    379 		asm("mcr%?	p15, 0, %0, c7, c10, 4	@ flush_pmd"
    380 			: : "r" (zero));
    381 }
    382 
    383 static inline void clean_pmd_entry(pmd_t *pmd)
    384 {
    385 	const unsigned int __tlb_flag = __cpu_tlb_flags;
    386 
    387 	if (tlb_flag(TLB_DCLEAN))
    388 		asm("mcr%?	p15, 0, %0, c7, c10, 1	@ flush_pmd"
    389 			: : "r" (pmd));
    390 }
    391 
    392 #undef tlb_flag
    393 #undef always_tlb_flags
    394 #undef possible_tlb_flags
    395 
    396 /*
    397  * Convert calls to our calling convention.
    398  */
    399 #define local_flush_tlb_range(vma,start,end)	__cpu_flush_user_tlb_range(start,end,vma)
    400 #define local_flush_tlb_kernel_range(s,e)	__cpu_flush_kern_tlb_range(s,e)
    401 
    402 #ifndef CONFIG_SMP
    403 #define flush_tlb_all		local_flush_tlb_all
    404 #define flush_tlb_mm		local_flush_tlb_mm
    405 #define flush_tlb_page		local_flush_tlb_page
    406 #define flush_tlb_kernel_page	local_flush_tlb_kernel_page
    407 #define flush_tlb_range		local_flush_tlb_range
    408 #define flush_tlb_kernel_range	local_flush_tlb_kernel_range
    409 #else
    410 extern void flush_tlb_all(void);
    411 extern void flush_tlb_mm(struct mm_struct *mm);
    412 extern void flush_tlb_page(struct vm_area_struct *vma, unsigned long uaddr);
    413 extern void flush_tlb_kernel_page(unsigned long kaddr);
    414 extern void flush_tlb_range(struct vm_area_struct *vma, unsigned long start, unsigned long end);
    415 extern void flush_tlb_kernel_range(unsigned long start, unsigned long end);
    416 #endif
    417 
    418 /*
    419  * if PG_dcache_dirty is set for the page, we need to ensure that any
    420  * cache entries for the kernels virtual memory range are written
    421  * back to the page.
    422  */
    423 extern void update_mmu_cache(struct vm_area_struct *vma, unsigned long addr, pte_t pte);
    424 
    425 /*
    426  * ARM processors do not cache TLB tables in RAM.
    427  */
    428 #define flush_tlb_pgtables(mm,start,end)	do { } while (0)
    429 
    430 #endif
    431 
    432 #endif /* CONFIG_MMU */
    433 
    434 #endif
    435