From: Steven J. Hill Date: Fri, 27 Feb 2015 00:16:38 +0000 (-0600) Subject: MIPS: Add support for XPA. X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=c5b367835cfc7a8ef53b9670a409ffcc95194344;p=GitHub%2Fmoto-9609%2Fandroid_kernel_motorola_exynos9610.git MIPS: Add support for XPA. Add support for extended physical addressing (XPA) so that 32-bit platforms can access equal to or greater than 40 bits of physical addresses. NOTE: 1) XPA and EVA are not the same and cannot be used simultaneously. 2) If you configure your kernel for XPA, the PTEs and all address sizes become 64-bit. 3) Your platform MUST have working HIGHMEM support. Signed-off-by: Steven J. Hill Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/9355/ Signed-off-by: Ralf Baechle --- diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig index c7a16904cd03..69a3b0fab926 100644 --- a/arch/mips/Kconfig +++ b/arch/mips/Kconfig @@ -377,6 +377,7 @@ config MIPS_MALTA select SYS_HAS_CPU_MIPS32_R1 select SYS_HAS_CPU_MIPS32_R2 select SYS_HAS_CPU_MIPS32_R3_5 + select SYS_HAS_CPU_MIPS32_R5 select SYS_HAS_CPU_MIPS32_R6 select SYS_HAS_CPU_MIPS64_R1 select SYS_HAS_CPU_MIPS64_R2 @@ -386,6 +387,7 @@ config MIPS_MALTA select SYS_SUPPORTS_32BIT_KERNEL select SYS_SUPPORTS_64BIT_KERNEL select SYS_SUPPORTS_BIG_ENDIAN + select SYS_SUPPORTS_HIGHMEM select SYS_SUPPORTS_LITTLE_ENDIAN select SYS_SUPPORTS_MICROMIPS select SYS_SUPPORTS_MIPS_CMP @@ -1596,6 +1598,33 @@ config CPU_MIPS32_3_5_EVA One of its primary benefits is an increase in the maximum size of lowmem (up to 3GB). If unsure, say 'N' here. +config CPU_MIPS32_R5_FEATURES + bool "MIPS32 Release 5 Features" + depends on SYS_HAS_CPU_MIPS32_R5 + depends on CPU_MIPS32_R2 + help + Choose this option to build a kernel for release 2 or later of the + MIPS32 architecture including features from release 5 such as + support for Extended Physical Addressing (XPA). + +config CPU_MIPS32_R5_XPA + bool "Extended Physical Addressing (XPA)" + depends on CPU_MIPS32_R5_FEATURES + depends on !EVA + depends on !PAGE_SIZE_4KB + depends on SYS_SUPPORTS_HIGHMEM + select XPA + select HIGHMEM + select ARCH_PHYS_ADDR_T_64BIT + default n + help + Choose this option if you want to enable the Extended Physical + Addressing (XPA) on your MIPS32 core (such as P5600 series). The + benefit is to increase physical addressing equal to or greater + than 40 bits. Note that this has the side effect of turning on + 64-bit addressing which in turn makes the PTEs 64-bit in size. + If unsure, say 'N' here. + if CPU_LOONGSON2F config CPU_NOP_WORKAROUNDS bool @@ -1699,6 +1728,9 @@ config SYS_HAS_CPU_MIPS32_R2 config SYS_HAS_CPU_MIPS32_R3_5 bool +config SYS_HAS_CPU_MIPS32_R5 + bool + config SYS_HAS_CPU_MIPS32_R6 bool @@ -1836,6 +1868,9 @@ config CPU_MIPSR6 config EVA bool +config XPA + bool + config SYS_SUPPORTS_32BIT_KERNEL bool config SYS_SUPPORTS_64BIT_KERNEL diff --git a/arch/mips/include/asm/cpu-features.h b/arch/mips/include/asm/cpu-features.h index 0d8208de9a3f..a324751b02ff 100644 --- a/arch/mips/include/asm/cpu-features.h +++ b/arch/mips/include/asm/cpu-features.h @@ -139,6 +139,9 @@ # endif #endif +#ifndef cpu_has_xpa +#define cpu_has_xpa (cpu_data[0].options & MIPS_CPU_XPA) +#endif #ifndef cpu_has_vtag_icache #define cpu_has_vtag_icache (cpu_data[0].icache.flags & MIPS_CACHE_VTAG) #endif diff --git a/arch/mips/include/asm/cpu.h b/arch/mips/include/asm/cpu.h index 15687234d70a..e492c740bb94 100644 --- a/arch/mips/include/asm/cpu.h +++ b/arch/mips/include/asm/cpu.h @@ -377,6 +377,7 @@ enum cpu_type_enum { #define MIPS_CPU_MAAR 0x400000000ull /* MAAR(I) registers are present */ #define MIPS_CPU_FRE 0x800000000ull /* FRE & UFE bits implemented */ #define MIPS_CPU_RW_LLB 0x1000000000ull /* LLADDR/LLB writes are allowed */ +#define MIPS_CPU_XPA 0x2000000000ull /* CPU supports Extended Physical Addressing */ /* * CPU ASE encodings diff --git a/arch/mips/include/asm/pgtable-32.h b/arch/mips/include/asm/pgtable-32.h index a6be006b6f75..7d56686c0e62 100644 --- a/arch/mips/include/asm/pgtable-32.h +++ b/arch/mips/include/asm/pgtable-32.h @@ -105,13 +105,16 @@ static inline void pmd_clear(pmd_t *pmdp) #if defined(CONFIG_PHYS_ADDR_T_64BIT) && defined(CONFIG_CPU_MIPS32) #define pte_page(x) pfn_to_page(pte_pfn(x)) -#define pte_pfn(x) ((unsigned long)((x).pte_high >> 6)) +#define pte_pfn(x) (((unsigned long)((x).pte_high >> _PFN_SHIFT)) | (unsigned long)((x).pte_low << _PAGE_PRESENT_SHIFT)) static inline pte_t pfn_pte(unsigned long pfn, pgprot_t prot) { pte_t pte; - pte.pte_high = (pfn << 6) | (pgprot_val(prot) & 0x3f); - pte.pte_low = pgprot_val(prot); + + pte.pte_low = (pfn >> _PAGE_PRESENT_SHIFT) | + (pgprot_val(prot) & ~_PFNX_MASK); + pte.pte_high = (pfn << _PFN_SHIFT) | + (pgprot_val(prot) & ~_PFN_MASK); return pte; } @@ -166,9 +169,9 @@ pfn_pte(unsigned long pfn, pgprot_t prot) #if defined(CONFIG_PHYS_ADDR_T_64BIT) && defined(CONFIG_CPU_MIPS32) /* Swap entries must have VALID and GLOBAL bits cleared. */ -#define __swp_type(x) (((x).val >> 2) & 0x1f) -#define __swp_offset(x) ((x).val >> 7) -#define __swp_entry(type,offset) ((swp_entry_t) { ((type) << 2) | ((offset) << 7) }) +#define __swp_type(x) (((x).val >> 4) & 0x1f) +#define __swp_offset(x) ((x).val >> 9) +#define __swp_entry(type,offset) ((swp_entry_t) { ((type) << 4) | ((offset) << 9) }) #define __pte_to_swp_entry(pte) ((swp_entry_t) { (pte).pte_high }) #define __swp_entry_to_pte(x) ((pte_t) { 0, (x).val }) diff --git a/arch/mips/include/asm/pgtable-bits.h b/arch/mips/include/asm/pgtable-bits.h index 8e432a8ec4fe..18ae5ddef118 100644 --- a/arch/mips/include/asm/pgtable-bits.h +++ b/arch/mips/include/asm/pgtable-bits.h @@ -37,7 +37,11 @@ /* * The following bits are implemented by the TLB hardware */ -#define _PAGE_GLOBAL_SHIFT 0 +#define _PAGE_NO_EXEC_SHIFT 0 +#define _PAGE_NO_EXEC (1 << _PAGE_NO_EXEC_SHIFT) +#define _PAGE_NO_READ_SHIFT (_PAGE_NO_EXEC_SHIFT + 1) +#define _PAGE_NO_READ (1 << _PAGE_NO_READ_SHIFT) +#define _PAGE_GLOBAL_SHIFT (_PAGE_NO_READ_SHIFT + 1) #define _PAGE_GLOBAL (1 << _PAGE_GLOBAL_SHIFT) #define _PAGE_VALID_SHIFT (_PAGE_GLOBAL_SHIFT + 1) #define _PAGE_VALID (1 << _PAGE_VALID_SHIFT) @@ -49,7 +53,7 @@ /* * The following bits are implemented in software */ -#define _PAGE_PRESENT_SHIFT (_CACHE_SHIFT + 3) +#define _PAGE_PRESENT_SHIFT (24) #define _PAGE_PRESENT (1 << _PAGE_PRESENT_SHIFT) #define _PAGE_READ_SHIFT (_PAGE_PRESENT_SHIFT + 1) #define _PAGE_READ (1 << _PAGE_READ_SHIFT) @@ -62,6 +66,11 @@ #define _PFN_SHIFT (PAGE_SHIFT - 12 + _CACHE_SHIFT + 3) +/* + * Bits for extended EntryLo0/EntryLo1 registers + */ +#define _PFNX_MASK 0xffffff + #elif defined(CONFIG_CPU_R3000) || defined(CONFIG_CPU_TX39XX) /* diff --git a/arch/mips/include/asm/pgtable.h b/arch/mips/include/asm/pgtable.h index e1fec0237ce2..bffd46ca3694 100644 --- a/arch/mips/include/asm/pgtable.h +++ b/arch/mips/include/asm/pgtable.h @@ -133,7 +133,7 @@ extern void set_pte_at(struct mm_struct *mm, unsigned long addr, pte_t *ptep, #if defined(CONFIG_PHYS_ADDR_T_64BIT) && defined(CONFIG_CPU_MIPS32) -#define pte_none(pte) (!(((pte).pte_low | (pte).pte_high) & ~_PAGE_GLOBAL)) +#define pte_none(pte) (!(((pte).pte_high) & ~_PAGE_GLOBAL)) #define pte_present(pte) ((pte).pte_low & _PAGE_PRESENT) static inline void set_pte(pte_t *ptep, pte_t pte) @@ -142,16 +142,14 @@ static inline void set_pte(pte_t *ptep, pte_t pte) smp_wmb(); ptep->pte_low = pte.pte_low; - if (pte.pte_low & _PAGE_GLOBAL) { + if (pte.pte_high & _PAGE_GLOBAL) { pte_t *buddy = ptep_buddy(ptep); /* * Make sure the buddy is global too (if it's !none, * it better already be global) */ - if (pte_none(*buddy)) { - buddy->pte_low |= _PAGE_GLOBAL; + if (pte_none(*buddy)) buddy->pte_high |= _PAGE_GLOBAL; - } } } @@ -161,8 +159,8 @@ static inline void pte_clear(struct mm_struct *mm, unsigned long addr, pte_t *pt htw_stop(); /* Preserve global status for the pair */ - if (ptep_buddy(ptep)->pte_low & _PAGE_GLOBAL) - null.pte_low = null.pte_high = _PAGE_GLOBAL; + if (ptep_buddy(ptep)->pte_high & _PAGE_GLOBAL) + null.pte_high = _PAGE_GLOBAL; set_pte_at(mm, addr, ptep, null); htw_start(); @@ -242,21 +240,21 @@ static inline int pte_young(pte_t pte) { return pte.pte_low & _PAGE_ACCESSED; } static inline pte_t pte_wrprotect(pte_t pte) { - pte.pte_low &= ~(_PAGE_WRITE | _PAGE_SILENT_WRITE); + pte.pte_low &= ~_PAGE_WRITE; pte.pte_high &= ~_PAGE_SILENT_WRITE; return pte; } static inline pte_t pte_mkclean(pte_t pte) { - pte.pte_low &= ~(_PAGE_MODIFIED | _PAGE_SILENT_WRITE); + pte.pte_low &= ~_PAGE_MODIFIED; pte.pte_high &= ~_PAGE_SILENT_WRITE; return pte; } static inline pte_t pte_mkold(pte_t pte) { - pte.pte_low &= ~(_PAGE_ACCESSED | _PAGE_SILENT_READ); + pte.pte_low &= ~_PAGE_ACCESSED; pte.pte_high &= ~_PAGE_SILENT_READ; return pte; } @@ -264,30 +262,24 @@ static inline pte_t pte_mkold(pte_t pte) static inline pte_t pte_mkwrite(pte_t pte) { pte.pte_low |= _PAGE_WRITE; - if (pte.pte_low & _PAGE_MODIFIED) { - pte.pte_low |= _PAGE_SILENT_WRITE; + if (pte.pte_low & _PAGE_MODIFIED) pte.pte_high |= _PAGE_SILENT_WRITE; - } return pte; } static inline pte_t pte_mkdirty(pte_t pte) { pte.pte_low |= _PAGE_MODIFIED; - if (pte.pte_low & _PAGE_WRITE) { - pte.pte_low |= _PAGE_SILENT_WRITE; + if (pte.pte_low & _PAGE_WRITE) pte.pte_high |= _PAGE_SILENT_WRITE; - } return pte; } static inline pte_t pte_mkyoung(pte_t pte) { pte.pte_low |= _PAGE_ACCESSED; - if (pte.pte_low & _PAGE_READ) { - pte.pte_low |= _PAGE_SILENT_READ; + if (pte.pte_low & _PAGE_READ) pte.pte_high |= _PAGE_SILENT_READ; - } return pte; } #else @@ -391,10 +383,10 @@ static inline pgprot_t pgprot_writecombine(pgprot_t _prot) #if defined(CONFIG_PHYS_ADDR_T_64BIT) && defined(CONFIG_CPU_MIPS32) static inline pte_t pte_modify(pte_t pte, pgprot_t newprot) { - pte.pte_low &= _PAGE_CHG_MASK; + pte.pte_low &= (_PAGE_MODIFIED | _PAGE_ACCESSED | _PFNX_MASK); pte.pte_high &= (_PFN_MASK | _CACHE_MASK); - pte.pte_low |= pgprot_val(newprot); - pte.pte_high |= pgprot_val(newprot) & ~(_PFN_MASK | _CACHE_MASK); + pte.pte_low |= pgprot_val(newprot) & ~_PFNX_MASK; + pte.pte_high |= pgprot_val(newprot) & ~_PFN_MASK; return pte; } #else diff --git a/arch/mips/kernel/cpu-probe.c b/arch/mips/kernel/cpu-probe.c index 48dfb9de853d..ac96817d1f99 100644 --- a/arch/mips/kernel/cpu-probe.c +++ b/arch/mips/kernel/cpu-probe.c @@ -516,6 +516,10 @@ static inline unsigned int decode_config5(struct cpuinfo_mips *c) c->options |= MIPS_CPU_MAAR; if (config5 & MIPS_CONF5_LLB) c->options |= MIPS_CPU_RW_LLB; +#ifdef CONFIG_XPA + if (config5 & MIPS_CONF5_MVH) + c->options |= MIPS_CPU_XPA; +#endif return config5 & MIPS_CONF_M; } diff --git a/arch/mips/kernel/proc.c b/arch/mips/kernel/proc.c index 130af7d26a9c..298b2b773d12 100644 --- a/arch/mips/kernel/proc.c +++ b/arch/mips/kernel/proc.c @@ -120,6 +120,7 @@ static int show_cpuinfo(struct seq_file *m, void *v) if (cpu_has_msa) seq_printf(m, "%s", " msa"); if (cpu_has_eva) seq_printf(m, "%s", " eva"); if (cpu_has_htw) seq_printf(m, "%s", " htw"); + if (cpu_has_xpa) seq_printf(m, "%s", " xpa"); seq_printf(m, "\n"); if (cpu_has_mmips) { diff --git a/arch/mips/mm/init.c b/arch/mips/mm/init.c index 448cde372af0..faa5c9822ecc 100644 --- a/arch/mips/mm/init.c +++ b/arch/mips/mm/init.c @@ -96,7 +96,7 @@ static void *__kmap_pgprot(struct page *page, unsigned long addr, pgprot_t prot) vaddr = __fix_to_virt(FIX_CMAP_END - idx); pte = mk_pte(page, prot); #if defined(CONFIG_PHYS_ADDR_T_64BIT) && defined(CONFIG_CPU_MIPS32) - entrylo = pte.pte_high; + entrylo = pte_to_entrylo(pte.pte_high); #else entrylo = pte_to_entrylo(pte_val(pte)); #endif @@ -106,6 +106,11 @@ static void *__kmap_pgprot(struct page *page, unsigned long addr, pgprot_t prot) write_c0_entryhi(vaddr & (PAGE_MASK << 1)); write_c0_entrylo0(entrylo); write_c0_entrylo1(entrylo); +#ifdef CONFIG_XPA + entrylo = (pte.pte_low & _PFNX_MASK); + writex_c0_entrylo0(entrylo); + writex_c0_entrylo1(entrylo); +#endif tlbidx = read_c0_wired(); write_c0_wired(tlbidx + 1); write_c0_index(tlbidx); diff --git a/arch/mips/mm/tlb-r4k.c b/arch/mips/mm/tlb-r4k.c index b2afa49beab0..c2500f4cb1d1 100644 --- a/arch/mips/mm/tlb-r4k.c +++ b/arch/mips/mm/tlb-r4k.c @@ -333,9 +333,17 @@ void __update_tlb(struct vm_area_struct * vma, unsigned long address, pte_t pte) ptep = pte_offset_map(pmdp, address); #if defined(CONFIG_PHYS_ADDR_T_64BIT) && defined(CONFIG_CPU_MIPS32) +#ifdef CONFIG_XPA + write_c0_entrylo0(pte_to_entrylo(ptep->pte_high)); + writex_c0_entrylo0(ptep->pte_low & _PFNX_MASK); + ptep++; + write_c0_entrylo1(pte_to_entrylo(ptep->pte_high)); + writex_c0_entrylo1(ptep->pte_low & _PFNX_MASK); +#else write_c0_entrylo0(ptep->pte_high); ptep++; write_c0_entrylo1(ptep->pte_high); +#endif #else write_c0_entrylo0(pte_to_entrylo(pte_val(*ptep++))); write_c0_entrylo1(pte_to_entrylo(pte_val(*ptep))); @@ -355,6 +363,9 @@ void __update_tlb(struct vm_area_struct * vma, unsigned long address, pte_t pte) void add_wired_entry(unsigned long entrylo0, unsigned long entrylo1, unsigned long entryhi, unsigned long pagemask) { +#ifdef CONFIG_XPA + panic("Broken for XPA kernels"); +#else unsigned long flags; unsigned long wired; unsigned long old_pagemask; @@ -383,6 +394,7 @@ void add_wired_entry(unsigned long entrylo0, unsigned long entrylo1, write_c0_pagemask(old_pagemask); local_flush_tlb_all(); local_irq_restore(flags); +#endif } #ifdef CONFIG_TRANSPARENT_HUGEPAGE diff --git a/arch/mips/mm/tlbex.c b/arch/mips/mm/tlbex.c index 20d985901e44..7709920e0cef 100644 --- a/arch/mips/mm/tlbex.c +++ b/arch/mips/mm/tlbex.c @@ -35,6 +35,17 @@ #include #include +static int __cpuinitdata mips_xpa_disabled; + +static int __init xpa_disable(char *s) +{ + mips_xpa_disabled = 1; + + return 1; +} + +__setup("noxpa", xpa_disable); + /* * TLB load/store/modify handlers. * @@ -1027,12 +1038,27 @@ static void build_update_entries(u32 **p, unsigned int tmp, unsigned int ptep) } else { int pte_off_even = sizeof(pte_t) / 2; int pte_off_odd = pte_off_even + sizeof(pte_t); +#ifdef CONFIG_XPA + const int scratch = 1; /* Our extra working register */ - /* The pte entries are pre-shifted */ - uasm_i_lw(p, tmp, pte_off_even, ptep); /* get even pte */ - UASM_i_MTC0(p, tmp, C0_ENTRYLO0); /* load it */ - uasm_i_lw(p, ptep, pte_off_odd, ptep); /* get odd pte */ - UASM_i_MTC0(p, ptep, C0_ENTRYLO1); /* load it */ + uasm_i_addu(p, scratch, 0, ptep); +#endif + uasm_i_lw(p, tmp, pte_off_even, ptep); /* even pte */ + uasm_i_lw(p, ptep, pte_off_odd, ptep); /* odd pte */ + UASM_i_ROTR(p, tmp, tmp, ilog2(_PAGE_GLOBAL)); + UASM_i_ROTR(p, ptep, ptep, ilog2(_PAGE_GLOBAL)); + UASM_i_MTC0(p, tmp, C0_ENTRYLO0); + UASM_i_MTC0(p, ptep, C0_ENTRYLO1); +#ifdef CONFIG_XPA + uasm_i_lw(p, tmp, 0, scratch); + uasm_i_lw(p, ptep, sizeof(pte_t), scratch); + uasm_i_lui(p, scratch, 0xff); + uasm_i_ori(p, scratch, scratch, 0xffff); + uasm_i_and(p, tmp, scratch, tmp); + uasm_i_and(p, ptep, scratch, ptep); + uasm_i_mthc0(p, tmp, C0_ENTRYLO0); + uasm_i_mthc0(p, ptep, C0_ENTRYLO1); +#endif } #else UASM_i_LW(p, tmp, 0, ptep); /* get even pte */ @@ -1533,8 +1559,14 @@ iPTE_SW(u32 **p, struct uasm_reloc **r, unsigned int pte, unsigned int ptr, { #ifdef CONFIG_PHYS_ADDR_T_64BIT unsigned int hwmode = mode & (_PAGE_VALID | _PAGE_DIRTY); -#endif + if (!cpu_has_64bits) { + const int scratch = 1; /* Our extra working register */ + + uasm_i_lui(p, scratch, (mode >> 16)); + uasm_i_or(p, pte, pte, scratch); + } else +#endif uasm_i_ori(p, pte, pte, mode); #ifdef CONFIG_SMP # ifdef CONFIG_PHYS_ADDR_T_64BIT @@ -1598,15 +1630,17 @@ build_pte_present(u32 **p, struct uasm_reloc **r, uasm_il_bbit0(p, r, pte, ilog2(_PAGE_PRESENT), lid); uasm_i_nop(p); } else { - uasm_i_andi(p, t, pte, _PAGE_PRESENT); + uasm_i_srl(p, t, pte, _PAGE_PRESENT_SHIFT); + uasm_i_andi(p, t, t, 1); uasm_il_beqz(p, r, t, lid); if (pte == t) /* You lose the SMP race :-(*/ iPTE_LW(p, pte, ptr); } } else { - uasm_i_andi(p, t, pte, _PAGE_PRESENT | _PAGE_READ); - uasm_i_xori(p, t, t, _PAGE_PRESENT | _PAGE_READ); + uasm_i_srl(p, t, pte, _PAGE_PRESENT_SHIFT); + uasm_i_andi(p, t, t, 3); + uasm_i_xori(p, t, t, 3); uasm_il_bnez(p, r, t, lid); if (pte == t) /* You lose the SMP race :-(*/ @@ -1635,8 +1669,9 @@ build_pte_writable(u32 **p, struct uasm_reloc **r, { int t = scratch >= 0 ? scratch : pte; - uasm_i_andi(p, t, pte, _PAGE_PRESENT | _PAGE_WRITE); - uasm_i_xori(p, t, t, _PAGE_PRESENT | _PAGE_WRITE); + uasm_i_srl(p, t, pte, _PAGE_PRESENT_SHIFT); + uasm_i_andi(p, t, t, 5); + uasm_i_xori(p, t, t, 5); uasm_il_bnez(p, r, t, lid); if (pte == t) /* You lose the SMP race :-(*/ @@ -1672,7 +1707,8 @@ build_pte_modifiable(u32 **p, struct uasm_reloc **r, uasm_i_nop(p); } else { int t = scratch >= 0 ? scratch : pte; - uasm_i_andi(p, t, pte, _PAGE_WRITE); + uasm_i_srl(p, t, pte, _PAGE_WRITE_SHIFT); + uasm_i_andi(p, t, t, 1); uasm_il_beqz(p, r, t, lid); if (pte == t) /* You lose the SMP race :-(*/ @@ -2285,6 +2321,11 @@ static void config_htw_params(void) pwsize = ilog2(PTRS_PER_PGD) << MIPS_PWSIZE_GDW_SHIFT; pwsize |= ilog2(PTRS_PER_PTE) << MIPS_PWSIZE_PTW_SHIFT; + + /* If XPA has been enabled, PTEs are 64-bit in size. */ + if (read_c0_pagegrain() & PG_ELPA) + pwsize |= 1; + write_c0_pwsize(pwsize); /* Make sure everything is set before we enable the HTW */ @@ -2298,6 +2339,28 @@ static void config_htw_params(void) print_htw_config(); } +static void config_xpa_params(void) +{ +#ifdef CONFIG_XPA + unsigned int pagegrain; + + if (mips_xpa_disabled) { + pr_info("Extended Physical Addressing (XPA) disabled\n"); + return; + } + + pagegrain = read_c0_pagegrain(); + write_c0_pagegrain(pagegrain | PG_ELPA); + back_to_back_c0_hazard(); + pagegrain = read_c0_pagegrain(); + + if (pagegrain & PG_ELPA) + pr_info("Extended Physical Addressing (XPA) enabled\n"); + else + panic("Extended Physical Addressing (XPA) disabled"); +#endif +} + void build_tlb_refill_handler(void) { /* @@ -2362,8 +2425,9 @@ void build_tlb_refill_handler(void) } if (cpu_has_local_ebase) build_r4000_tlb_refill_handler(); + if (cpu_has_xpa) + config_xpa_params(); if (cpu_has_htw) config_htw_params(); - } }