tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/*
2 * PPC Huge TLB Page Support for Book3E MMU
3 *
4 * Copyright (C) 2009 David Gibson, IBM Corporation.
5 * Copyright (C) 2011 Becky Bruce, Freescale Semiconductor
6 *
7 */
8#include <linux/mm.h>
9#include <linux/hugetlb.h>
10
11static inline int mmu_get_tsize(int psize)
12{
13 return mmu_psize_defs[psize].enc;
14}
15
16static inline int book3e_tlb_exists(unsigned long ea, unsigned long pid)
17{
18 int found = 0;
19
20 mtspr(SPRN_MAS6, pid << 16);
21 if (mmu_has_feature(MMU_FTR_USE_TLBRSRV)) {
22 asm volatile(
23 "li %0,0\n"
24 "tlbsx. 0,%1\n"
25 "bne 1f\n"
26 "li %0,1\n"
27 "1:\n"
28 : "=&r"(found) : "r"(ea));
29 } else {
30 asm volatile(
31 "tlbsx 0,%1\n"
32 "mfspr %0,0x271\n"
33 "srwi %0,%0,31\n"
34 : "=&r"(found) : "r"(ea));
35 }
36
37 return found;
38}
39
40void book3e_hugetlb_preload(struct vm_area_struct *vma, unsigned long ea,
41 pte_t pte)
42{
43 unsigned long mas1, mas2;
44 u64 mas7_3;
45 unsigned long psize, tsize, shift;
46 unsigned long flags;
47 struct mm_struct *mm;
48
49#ifdef CONFIG_PPC_FSL_BOOK3E
50 int index, ncams;
51#endif
52
53 if (unlikely(is_kernel_addr(ea)))
54 return;
55
56 mm = vma->vm_mm;
57
58#ifdef CONFIG_PPC_MM_SLICES
59 psize = get_slice_psize(mm, ea);
60 tsize = mmu_get_tsize(psize);
61 shift = mmu_psize_defs[psize].shift;
62#else
63 psize = vma_mmu_pagesize(vma);
64 shift = __ilog2(psize);
65 tsize = shift - 10;
66#endif
67
68 /*
69 * We can't be interrupted while we're setting up the MAS
70 * regusters or after we've confirmed that no tlb exists.
71 */
72 local_irq_save(flags);
73
74 if (unlikely(book3e_tlb_exists(ea, mm->context.id))) {
75 local_irq_restore(flags);
76 return;
77 }
78
79#ifdef CONFIG_PPC_FSL_BOOK3E
80 ncams = mfspr(SPRN_TLB1CFG) & TLBnCFG_N_ENTRY;
81
82 /* We have to use the CAM(TLB1) on FSL parts for hugepages */
83 index = __get_cpu_var(next_tlbcam_idx);
84 mtspr(SPRN_MAS0, MAS0_ESEL(index) | MAS0_TLBSEL(1));
85
86 /* Just round-robin the entries and wrap when we hit the end */
87 if (unlikely(index == ncams - 1))
88 __get_cpu_var(next_tlbcam_idx) = tlbcam_index;
89 else
90 __get_cpu_var(next_tlbcam_idx)++;
91#endif
92 mas1 = MAS1_VALID | MAS1_TID(mm->context.id) | MAS1_TSIZE(tsize);
93 mas2 = ea & ~((1UL << shift) - 1);
94 mas2 |= (pte_val(pte) >> PTE_WIMGE_SHIFT) & MAS2_WIMGE_MASK;
95 mas7_3 = (u64)pte_pfn(pte) << PAGE_SHIFT;
96 mas7_3 |= (pte_val(pte) >> PTE_BAP_SHIFT) & MAS3_BAP_MASK;
97 if (!pte_dirty(pte))
98 mas7_3 &= ~(MAS3_SW|MAS3_UW);
99
100 mtspr(SPRN_MAS1, mas1);
101 mtspr(SPRN_MAS2, mas2);
102
103 if (mmu_has_feature(MMU_FTR_USE_PAIRED_MAS)) {
104 mtspr(SPRN_MAS7_MAS3, mas7_3);
105 } else {
106 mtspr(SPRN_MAS7, upper_32_bits(mas7_3));
107 mtspr(SPRN_MAS3, lower_32_bits(mas7_3));
108 }
109
110 asm volatile ("tlbwe");
111
112 local_irq_restore(flags);
113}
114
115void flush_hugetlb_page(struct vm_area_struct *vma, unsigned long vmaddr)
116{
117 struct hstate *hstate = hstate_file(vma->vm_file);
118 unsigned long tsize = huge_page_shift(hstate) - 10;
119
120 __flush_tlb_page(vma ? vma->vm_mm : NULL, vmaddr, tsize, 0);
121
122}