From 98c5584cfc47932c4f3ccf5eee2e0bae1447b85e Mon Sep 17 00:00:00 2001 From: "David S. Miller" Date: Tue, 31 Jan 2006 18:31:20 -0800 Subject: [SPARC64]: Add infrastructure for dynamic TSB sizing. This also cleans up tsb_context_switch(). The assembler routine is now __tsb_context_switch() and the former is an inline function that picks out the bits from the mm_struct and passes it into the assembler code as arguments. setup_tsb_parms() computes the locked TLB entry to map the TSB. Later when we support using the physical address quad load instructions of Cheetah+ and later, we'll simply use the physical address for the TSB register value and set the map virtual and PTE both to zero. Signed-off-by: David S. Miller --- arch/sparc64/mm/tsb.c | 109 +++++++++++++++++++++++++++++++++++++++++++------- 1 file changed, 95 insertions(+), 14 deletions(-) (limited to 'arch/sparc64/mm/tsb.c') diff --git a/arch/sparc64/mm/tsb.c b/arch/sparc64/mm/tsb.c index 2f84cef6c1b..dfe7144fcdf 100644 --- a/arch/sparc64/mm/tsb.c +++ b/arch/sparc64/mm/tsb.c @@ -9,13 +9,7 @@ #include #include #include - -#define TSB_ENTRY_ALIGNMENT 16 - -struct tsb { - unsigned long tag; - unsigned long pte; -} __attribute__((aligned(TSB_ENTRY_ALIGNMENT))); +#include /* We use an 8K TSB for the whole kernel, this allows to * handle about 4MB of modules and vmalloc mappings without @@ -27,10 +21,10 @@ struct tsb { extern struct tsb swapper_tsb[KERNEL_TSB_NENTRIES]; -static inline unsigned long tsb_hash(unsigned long vaddr) +static inline unsigned long tsb_hash(unsigned long vaddr, unsigned long nentries) { vaddr >>= PAGE_SHIFT; - return vaddr & (KERNEL_TSB_NENTRIES - 1); + return vaddr & (nentries - 1); } static inline int tag_compare(struct tsb *entry, unsigned long vaddr, unsigned long context) @@ -51,7 +45,8 @@ void flush_tsb_kernel_range(unsigned long start, unsigned long end) unsigned long v; for (v = start; v < end; v += PAGE_SIZE) { - struct tsb *ent = &swapper_tsb[tsb_hash(v)]; + unsigned long hash = tsb_hash(v, KERNEL_TSB_NENTRIES); + struct tsb *ent = &swapper_tsb[hash]; if (tag_compare(ent, v, 0)) { ent->tag = 0UL; @@ -63,8 +58,9 @@ void flush_tsb_kernel_range(unsigned long start, unsigned long end) void flush_tsb_user(struct mmu_gather *mp) { struct mm_struct *mm = mp->mm; - struct tsb *tsb = (struct tsb *) mm->context.sparc64_tsb; + struct tsb *tsb = mm->context.tsb; unsigned long ctx = ~0UL; + unsigned long nentries = mm->context.tsb_nentries; int i; if (CTX_VALID(mm->context)) @@ -76,7 +72,7 @@ void flush_tsb_user(struct mmu_gather *mp) v &= ~0x1UL; - ent = &tsb[tsb_hash(v)]; + ent = &tsb[tsb_hash(v, nentries)]; if (tag_compare(ent, v, ctx)) { ent->tag = 0UL; membar_storeload_storestore(); @@ -84,6 +80,83 @@ void flush_tsb_user(struct mmu_gather *mp) } } +static void setup_tsb_params(struct mm_struct *mm, unsigned long tsb_bytes) +{ + unsigned long tsb_reg, base, tsb_paddr; + unsigned long page_sz, tte; + + mm->context.tsb_nentries = tsb_bytes / sizeof(struct tsb); + + base = TSBMAP_BASE; + tte = (_PAGE_VALID | _PAGE_L | _PAGE_CP | + _PAGE_CV | _PAGE_P | _PAGE_W); + tsb_paddr = __pa(mm->context.tsb); + + /* Use the smallest page size that can map the whole TSB + * in one TLB entry. + */ + switch (tsb_bytes) { + case 8192 << 0: + tsb_reg = 0x0UL; +#ifdef DCACHE_ALIASING_POSSIBLE + base += (tsb_paddr & 8192); +#endif + tte |= _PAGE_SZ8K; + page_sz = 8192; + break; + + case 8192 << 1: + tsb_reg = 0x1UL; + tte |= _PAGE_SZ64K; + page_sz = 64 * 1024; + break; + + case 8192 << 2: + tsb_reg = 0x2UL; + tte |= _PAGE_SZ64K; + page_sz = 64 * 1024; + break; + + case 8192 << 3: + tsb_reg = 0x3UL; + tte |= _PAGE_SZ64K; + page_sz = 64 * 1024; + break; + + case 8192 << 4: + tsb_reg = 0x4UL; + tte |= _PAGE_SZ512K; + page_sz = 512 * 1024; + break; + + case 8192 << 5: + tsb_reg = 0x5UL; + tte |= _PAGE_SZ512K; + page_sz = 512 * 1024; + break; + + case 8192 << 6: + tsb_reg = 0x6UL; + tte |= _PAGE_SZ512K; + page_sz = 512 * 1024; + break; + + case 8192 << 7: + tsb_reg = 0x7UL; + tte |= _PAGE_SZ4MB; + page_sz = 4 * 1024 * 1024; + break; + }; + + tsb_reg |= base; + tsb_reg |= (tsb_paddr & (page_sz - 1UL)); + tte |= (tsb_paddr & ~(page_sz - 1UL)); + + mm->context.tsb_reg_val = tsb_reg; + mm->context.tsb_map_vaddr = base; + mm->context.tsb_map_pte = tte; +} + int init_new_context(struct task_struct *tsk, struct mm_struct *mm) { unsigned long page = get_zeroed_page(GFP_KERNEL); @@ -92,14 +165,22 @@ int init_new_context(struct task_struct *tsk, struct mm_struct *mm) if (unlikely(!page)) return -ENOMEM; - mm->context.sparc64_tsb = (unsigned long *) page; + mm->context.tsb = (struct tsb *) page; + setup_tsb_params(mm, PAGE_SIZE); return 0; } void destroy_context(struct mm_struct *mm) { - free_page((unsigned long) mm->context.sparc64_tsb); + free_page((unsigned long) mm->context.tsb); + + /* We can remove these later, but for now it's useful + * to catch any bogus post-destroy_context() references + * to the TSB. + */ + mm->context.tsb = NULL; + mm->context.tsb_reg_val = 0UL; spin_lock(&ctx_alloc_lock); -- cgit v1.2.3