diff options
Diffstat (limited to 'include/asm-powerpc/mmu-hash64.h')
| -rw-r--r-- | include/asm-powerpc/mmu-hash64.h | 400 |
1 files changed, 400 insertions, 0 deletions
diff --git a/include/asm-powerpc/mmu-hash64.h b/include/asm-powerpc/mmu-hash64.h new file mode 100644 index 00000000000..6739457d8bc --- /dev/null +++ b/include/asm-powerpc/mmu-hash64.h @@ -0,0 +1,400 @@ +#ifndef _ASM_POWERPC_MMU_HASH64_H_ +#define _ASM_POWERPC_MMU_HASH64_H_ +/* + * PowerPC64 memory management structures + * + * Dave Engebretsen & Mike Corrigan <{engebret|mikejc}@us.ibm.com> + * PPC64 rework. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + */ + +#include <asm/asm-compat.h> +#include <asm/page.h> + +/* + * Segment table + */ + +#define STE_ESID_V 0x80 +#define STE_ESID_KS 0x20 +#define STE_ESID_KP 0x10 +#define STE_ESID_N 0x08 + +#define STE_VSID_SHIFT 12 + +/* Location of cpu0's segment table */ +#define STAB0_PAGE 0x6 +#define STAB0_OFFSET (STAB0_PAGE << 12) +#define STAB0_PHYS_ADDR (STAB0_OFFSET + PHYSICAL_START) + +#ifndef __ASSEMBLY__ +extern char initial_stab[]; +#endif /* ! __ASSEMBLY */ + +/* + * SLB + */ + +#define SLB_NUM_BOLTED 3 +#define SLB_CACHE_ENTRIES 8 + +/* Bits in the SLB ESID word */ +#define SLB_ESID_V ASM_CONST(0x0000000008000000) /* valid */ + +/* Bits in the SLB VSID word */ +#define SLB_VSID_SHIFT 12 +#define SLB_VSID_B ASM_CONST(0xc000000000000000) +#define SLB_VSID_B_256M ASM_CONST(0x0000000000000000) +#define SLB_VSID_B_1T ASM_CONST(0x4000000000000000) +#define SLB_VSID_KS ASM_CONST(0x0000000000000800) +#define SLB_VSID_KP ASM_CONST(0x0000000000000400) +#define SLB_VSID_N ASM_CONST(0x0000000000000200) /* no-execute */ +#define SLB_VSID_L ASM_CONST(0x0000000000000100) +#define SLB_VSID_C ASM_CONST(0x0000000000000080) /* class */ +#define SLB_VSID_LP ASM_CONST(0x0000000000000030) +#define SLB_VSID_LP_00 ASM_CONST(0x0000000000000000) +#define SLB_VSID_LP_01 ASM_CONST(0x0000000000000010) +#define SLB_VSID_LP_10 ASM_CONST(0x0000000000000020) +#define SLB_VSID_LP_11 ASM_CONST(0x0000000000000030) +#define SLB_VSID_LLP (SLB_VSID_L|SLB_VSID_LP) + +#define SLB_VSID_KERNEL (SLB_VSID_KP) +#define SLB_VSID_USER (SLB_VSID_KP|SLB_VSID_KS|SLB_VSID_C) + +#define SLBIE_C (0x08000000) + +/* + * Hash table + */ + +#define HPTES_PER_GROUP 8 + +#define HPTE_V_AVPN_SHIFT 7 +#define HPTE_V_AVPN ASM_CONST(0xffffffffffffff80) +#define HPTE_V_AVPN_VAL(x) (((x) & HPTE_V_AVPN) >> HPTE_V_AVPN_SHIFT) +#define HPTE_V_COMPARE(x,y) (!(((x) ^ (y)) & HPTE_V_AVPN)) +#define HPTE_V_BOLTED ASM_CONST(0x0000000000000010) +#define HPTE_V_LOCK ASM_CONST(0x0000000000000008) +#define HPTE_V_LARGE ASM_CONST(0x0000000000000004) +#define HPTE_V_SECONDARY ASM_CONST(0x0000000000000002) +#define HPTE_V_VALID ASM_CONST(0x0000000000000001) + +#define HPTE_R_PP0 ASM_CONST(0x8000000000000000) +#define HPTE_R_TS ASM_CONST(0x4000000000000000) +#define HPTE_R_RPN_SHIFT 12 +#define HPTE_R_RPN ASM_CONST(0x3ffffffffffff000) +#define HPTE_R_FLAGS ASM_CONST(0x00000000000003ff) +#define HPTE_R_PP ASM_CONST(0x0000000000000003) +#define HPTE_R_N ASM_CONST(0x0000000000000004) +#define HPTE_R_C ASM_CONST(0x0000000000000080) +#define HPTE_R_R ASM_CONST(0x0000000000000100) + +/* Values for PP (assumes Ks=0, Kp=1) */ +/* pp0 will always be 0 for linux */ +#define PP_RWXX 0 /* Supervisor read/write, User none */ +#define PP_RWRX 1 /* Supervisor read/write, User read */ +#define PP_RWRW 2 /* Supervisor read/write, User read/write */ +#define PP_RXRX 3 /* Supervisor read, User read */ + +#ifndef __ASSEMBLY__ + +typedef struct { + unsigned long v; + unsigned long r; +} hpte_t; + +extern hpte_t *htab_address; +extern unsigned long htab_size_bytes; +extern unsigned long htab_hash_mask; + +/* + * Page size definition + * + * shift : is the "PAGE_SHIFT" value for that page size + * sllp : is a bit mask with the value of SLB L || LP to be or'ed + * directly to a slbmte "vsid" value + * penc : is the HPTE encoding mask for the "LP" field: + * + */ +struct mmu_psize_def +{ + unsigned int shift; /* number of bits */ + unsigned int penc; /* HPTE encoding */ + unsigned int tlbiel; /* tlbiel supported for that page size */ + unsigned long avpnm; /* bits to mask out in AVPN in the HPTE */ + unsigned long sllp; /* SLB L||LP (exact mask to use in slbmte) */ +}; + +#endif /* __ASSEMBLY__ */ + +/* + * The kernel use the constants below to index in the page sizes array. + * The use of fixed constants for this purpose is better for performances + * of the low level hash refill handlers. + * + * A non supported page size has a "shift" field set to 0 + * + * Any new page size being implemented can get a new entry in here. Whether + * the kernel will use it or not is a different matter though. The actual page + * size used by hugetlbfs is not defined here and may be made variable + */ + +#define MMU_PAGE_4K 0 /* 4K */ +#define MMU_PAGE_64K 1 /* 64K */ +#define MMU_PAGE_64K_AP 2 /* 64K Admixed (in a 4K segment) */ +#define MMU_PAGE_1M 3 /* 1M */ +#define MMU_PAGE_16M 4 /* 16M */ +#define MMU_PAGE_16G 5 /* 16G */ +#define MMU_PAGE_COUNT 6 + +#ifndef __ASSEMBLY__ + +/* + * The current system page sizes + */ +extern struct mmu_psize_def mmu_psize_defs[MMU_PAGE_COUNT]; +extern int mmu_linear_psize; +extern int mmu_virtual_psize; +extern int mmu_vmalloc_psize; +extern int mmu_io_psize; + +/* + * If the processor supports 64k normal pages but not 64k cache + * inhibited pages, we have to be prepared to switch processes + * to use 4k pages when they create cache-inhibited mappings. + * If this is the case, mmu_ci_restrictions will be set to 1. + */ +extern int mmu_ci_restrictions; + +#ifdef CONFIG_HUGETLB_PAGE +/* + * The page size index of the huge pages for use by hugetlbfs + */ +extern int mmu_huge_psize; + +#endif /* CONFIG_HUGETLB_PAGE */ + +/* + * This function sets the AVPN and L fields of the HPTE appropriately + * for the page size + */ +static inline unsigned long hpte_encode_v(unsigned long va, int psize) +{ + unsigned long v = + v = (va >> 23) & ~(mmu_psize_defs[psize].avpnm); + v <<= HPTE_V_AVPN_SHIFT; + if (psize != MMU_PAGE_4K) + v |= HPTE_V_LARGE; + return v; +} + +/* + * This function sets the ARPN, and LP fields of the HPTE appropriately + * for the page size. We assume the pa is already "clean" that is properly + * aligned for the requested page size + */ +static inline unsigned long hpte_encode_r(unsigned long pa, int psize) +{ + unsigned long r; + + /* A 4K page needs no special encoding */ + if (psize == MMU_PAGE_4K) + return pa & HPTE_R_RPN; + else { + unsigned int penc = mmu_psize_defs[psize].penc; + unsigned int shift = mmu_psize_defs[psize].shift; + return (pa & ~((1ul << shift) - 1)) | (penc << 12); + } + return r; +} + +/* + * This hashes a virtual address for a 256Mb segment only for now + */ + +static inline unsigned long hpt_hash(unsigned long va, unsigned int shift) +{ + return ((va >> 28) & 0x7fffffffffUL) ^ ((va & 0x0fffffffUL) >> shift); +} + +extern int __hash_page_4K(unsigned long ea, unsigned long access, + unsigned long vsid, pte_t *ptep, unsigned long trap, + unsigned int local); +extern int __hash_page_64K(unsigned long ea, unsigned long access, + unsigned long vsid, pte_t *ptep, unsigned long trap, + unsigned int local); +struct mm_struct; +extern int hash_page(unsigned long ea, unsigned long access, unsigned long trap); +extern int hash_huge_page(struct mm_struct *mm, unsigned long access, + unsigned long ea, unsigned long vsid, int local, + unsigned long trap); + +extern int htab_bolt_mapping(unsigned long vstart, unsigned long vend, + unsigned long pstart, unsigned long mode, + int psize); + +extern void htab_initialize(void); +extern void htab_initialize_secondary(void); +extern void hpte_init_native(void); +extern void hpte_init_lpar(void); +extern void hpte_init_iSeries(void); +extern void hpte_init_beat(void); + +extern void stabs_alloc(void); +extern void slb_initialize(void); +extern void slb_flush_and_rebolt(void); +extern void stab_initialize(unsigned long stab); + +#endif /* __ASSEMBLY__ */ + +/* + * VSID allocation + * + * We first generate a 36-bit "proto-VSID". For kernel addresses this + * is equal to the ESID, for user addresses it is: + * (context << 15) | (esid & 0x7fff) + * + * The two forms are distinguishable because the top bit is 0 for user + * addresses, whereas the top two bits are 1 for kernel addresses. + * Proto-VSIDs with the top two bits equal to 0b10 are reserved for + * now. + * + * The proto-VSIDs are then scrambled into real VSIDs with the + * multiplicative hash: + * + * VSID = (proto-VSID * VSID_MULTIPLIER) % VSID_MODULUS + * where VSID_MULTIPLIER = 268435399 = 0xFFFFFC7 + * VSID_MODULUS = 2^36-1 = 0xFFFFFFFFF + * + * This scramble is only well defined for proto-VSIDs below + * 0xFFFFFFFFF, so both proto-VSID and actual VSID 0xFFFFFFFFF are + * reserved. VSID_MULTIPLIER is prime, so in particular it is + * co-prime to VSID_MODULUS, making this a 1:1 scrambling function. + * Because the modulus is 2^n-1 we can compute it efficiently without + * a divide or extra multiply (see below). + * + * This scheme has several advantages over older methods: + * + * - We have VSIDs allocated for every kernel address + * (i.e. everything above 0xC000000000000000), except the very top + * segment, which simplifies several things. + * + * - We allow for 15 significant bits of ESID and 20 bits of + * context for user addresses. i.e. 8T (43 bits) of address space for + * up to 1M contexts (although the page table structure and context + * allocation will need changes to take advantage of this). + * + * - The scramble function gives robust scattering in the hash + * table (at least based on some initial results). The previous + * method was more susceptible to pathological cases giving excessive + * hash collisions. + */ +/* + * WARNING - If you change these you must make sure the asm + * implementations in slb_allocate (slb_low.S), do_stab_bolted + * (head.S) and ASM_VSID_SCRAMBLE (below) are changed accordingly. + * + * You'll also need to change the precomputed VSID values in head.S + * which are used by the iSeries firmware. + */ + +#define VSID_MULTIPLIER ASM_CONST(200730139) /* 28-bit prime */ +#define VSID_BITS 36 +#define VSID_MODULUS ((1UL<<VSID_BITS)-1) + +#define CONTEXT_BITS 19 +#define USER_ESID_BITS 16 + +#define USER_VSID_RANGE (1UL << (USER_ESID_BITS + SID_SHIFT)) + +/* + * This macro generates asm code to compute the VSID scramble + * function. Used in slb_allocate() and do_stab_bolted. The function + * computed is: (protovsid*VSID_MULTIPLIER) % VSID_MODULUS + * + * rt = register continaing the proto-VSID and into which the + * VSID will be stored + * rx = scratch register (clobbered) + * + * - rt and rx must be different registers + * - The answer will end up in the low 36 bits of rt. The higher + * bits may contain other garbage, so you may need to mask the + * result. + */ +#define ASM_VSID_SCRAMBLE(rt, rx) \ + lis rx,VSID_MULTIPLIER@h; \ + ori rx,rx,VSID_MULTIPLIER@l; \ + mulld rt,rt,rx; /* rt = rt * MULTIPLIER */ \ + \ + srdi rx,rt,VSID_BITS; \ + clrldi rt,rt,(64-VSID_BITS); \ + add rt,rt,rx; /* add high and low bits */ \ + /* Now, r3 == VSID (mod 2^36-1), and lies between 0 and \ + * 2^36-1+2^28-1. That in particular means that if r3 >= \ + * 2^36-1, then r3+1 has the 2^36 bit set. So, if r3+1 has \ + * the bit clear, r3 already has the answer we want, if it \ + * doesn't, the answer is the low 36 bits of r3+1. So in all \ + * cases the answer is the low 36 bits of (r3 + ((r3+1) >> 36))*/\ + addi rx,rt,1; \ + srdi rx,rx,VSID_BITS; /* extract 2^36 bit */ \ + add rt,rt,rx + + +#ifndef __ASSEMBLY__ + +typedef unsigned long mm_context_id_t; + +typedef struct { + mm_context_id_t id; + u16 user_psize; /* page size index */ + u16 sllp; /* SLB entry page size encoding */ +#ifdef CONFIG_HUGETLB_PAGE + u16 low_htlb_areas, high_htlb_areas; +#endif + unsigned long vdso_base; +} mm_context_t; + + +static inline unsigned long vsid_scramble(unsigned long protovsid) +{ +#if 0 + /* The code below is equivalent to this function for arguments + * < 2^VSID_BITS, which is all this should ever be called + * with. However gcc is not clever enough to compute the + * modulus (2^n-1) without a second multiply. */ + return ((protovsid * VSID_MULTIPLIER) % VSID_MODULUS); +#else /* 1 */ + unsigned long x; + + x = protovsid * VSID_MULTIPLIER; + x = (x >> VSID_BITS) + (x & VSID_MODULUS); + return (x + ((x+1) >> VSID_BITS)) & VSID_MODULUS; +#endif /* 1 */ +} + +/* This is only valid for addresses >= KERNELBASE */ +static inline unsigned long get_kernel_vsid(unsigned long ea) +{ + return vsid_scramble(ea >> SID_SHIFT); +} + +/* This is only valid for user addresses (which are below 2^41) */ +static inline unsigned long get_vsid(unsigned long context, unsigned long ea) +{ + return vsid_scramble((context << USER_ESID_BITS) + | (ea >> SID_SHIFT)); +} + +#define VSID_SCRAMBLE(pvsid) (((pvsid) * VSID_MULTIPLIER) % VSID_MODULUS) +#define KERNEL_VSID(ea) VSID_SCRAMBLE(GET_ESID(ea)) + +/* Physical address used by some IO functions */ +typedef unsigned long phys_addr_t; + +#endif /* __ASSEMBLY__ */ + +#endif /* _ASM_POWERPC_MMU_HASH64_H_ */ |