[258] | 1 | /////////////////////////////////////////////////////////////////////////////////// |
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| 2 | // File : vmem.c |
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| 3 | // Date : 01/07/2012 |
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| 4 | // Author : alain greiner |
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| 5 | // Copyright (c) UPMC-LIP6 |
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| 6 | /////////////////////////////////////////////////////////////////////////////////// |
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| 7 | // The vmem.c and vmem.h files are part ot the GIET-VM nano kernel. |
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| 8 | // They contain the kernel data structures and functions used to dynamically |
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| 9 | // handle the paged virtual memory. |
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| 10 | /////////////////////////////////////////////////////////////////////////////////// |
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| 11 | |
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| 12 | #include <utils.h> |
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| 13 | #include <tty_driver.h> |
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| 14 | #include <vmem.h> |
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| 15 | #include <giet_config.h> |
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| 16 | #include <tty_driver.h> |
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| 17 | |
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| 18 | ///////////////////////////////////////////////////////////////////////////// |
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| 19 | // Global variable : IOMMU page table |
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| 20 | ///////////////////////////////////////////////////////////////////////////// |
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| 21 | |
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| 22 | __attribute__((section (".iommu"))) page_table_t _iommu_ptab; |
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| 23 | |
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| 24 | ////////////////////////////////////////////////////////////////////////////// |
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| 25 | // _iommu_add_pte2() |
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| 26 | ////////////////////////////////////////////////////////////////////////////// |
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| 27 | void _iommu_add_pte2( |
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| 28 | unsigned int ix1, |
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| 29 | unsigned int ix2, |
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| 30 | unsigned int ppn, |
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| 31 | unsigned int flags) |
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| 32 | { |
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| 33 | unsigned int ptba; |
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| 34 | unsigned int * pt_ppn; |
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| 35 | unsigned int * pt_flags; |
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| 36 | |
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| 37 | // get pointer on iommu page table |
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| 38 | page_table_t * pt = &_iommu_ptab; |
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| 39 | |
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| 40 | // get ptba and update PT2 |
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| 41 | if ((pt->pt1[ix1] & PTE_V) == 0) |
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| 42 | { |
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| 43 | _tty_get_lock( 0 ); |
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| 44 | _puts("\n[GIET ERROR] in iommu_add_pte2 function\n"); |
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| 45 | _puts("the IOMMU PT1 entry is not mapped / ix1 = "); |
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| 46 | _putx( ix1 ); |
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| 47 | _puts("\n"); |
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| 48 | _tty_release_lock( 0 ); |
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| 49 | _exit(); |
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| 50 | } |
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| 51 | else |
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| 52 | { |
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| 53 | ptba = pt->pt1[ix1] << 12; |
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| 54 | pt_flags = (unsigned int *) (ptba + 8 * ix2); |
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| 55 | pt_ppn = (unsigned int *) (ptba + 8 * ix2 + 4); |
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| 56 | *pt_flags = flags; |
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| 57 | *pt_ppn = ppn; |
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| 58 | } |
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| 59 | } // end _iommu_add_pte2() |
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| 60 | |
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| 61 | |
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| 62 | ////////////////////////////////////////////////////////////////////////////// |
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| 63 | // _iommu_inval_pte2() |
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| 64 | ////////////////////////////////////////////////////////////////////////////// |
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| 65 | void _iommu_inval_pte2(unsigned int ix1, unsigned int ix2) { |
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| 66 | unsigned int ptba; |
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| 67 | unsigned int * pt_flags; |
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| 68 | |
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| 69 | // get pointer on iommu page table |
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| 70 | page_table_t * pt = &_iommu_ptab; |
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| 71 | |
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| 72 | // get ptba and inval PTE2 |
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| 73 | if ((pt->pt1[ix1] & PTE_V) == 0) |
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| 74 | { |
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| 75 | _puts("\n[GIET ERROR] in iommu_inval_pte2 function\n"); |
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| 76 | _puts("the IOMMU PT1 entry is not mapped / ix1 = "); |
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| 77 | _putx( ix1 ); |
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| 78 | _puts("\n"); |
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| 79 | _exit(); |
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| 80 | } |
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| 81 | else { |
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| 82 | ptba = pt->pt1[ix1] << 12; |
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| 83 | pt_flags = (unsigned int *) (ptba + 8 * ix2); |
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| 84 | *pt_flags = 0; |
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| 85 | } |
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| 86 | } // end _iommu_inval_pte2() |
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| 87 | |
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| 88 | ////////////////////////////////////////////////////////////////////////////// |
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| 89 | // This function makes a "vpn" to "ppn" translation, from the page table |
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| 90 | // defined by the virtual address "pt". The MMU is supposed to be activated. |
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| 91 | // It uses the address extension mechanism for physical addressing. |
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| 92 | // Return 0 if success. Return 1 if PTE1 or PTE2 unmapped. |
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| 93 | ////////////////////////////////////////////////////////////////////////////// |
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| 94 | unsigned int _v2p_translate( page_table_t* pt, |
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| 95 | unsigned int vpn, |
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| 96 | unsigned int* ppn, |
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| 97 | unsigned int* flags) |
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| 98 | { |
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| 99 | unsigned long long ptba; |
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| 100 | unsigned long long pte2_paddr; |
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| 101 | |
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| 102 | register unsigned int pte2_msb; |
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| 103 | register unsigned int pte2_lsb; |
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| 104 | register unsigned int flags_value; |
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| 105 | register unsigned int ppn_value; |
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| 106 | |
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| 107 | unsigned int ix1 = vpn >> 9; |
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| 108 | unsigned int ix2 = vpn & 0x1FF; |
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| 109 | |
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| 110 | // get PTE1 |
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| 111 | unsigned int pte1 = pt->pt1[ix1]; |
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| 112 | |
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| 113 | // check PTE1 mapping |
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| 114 | if ( (pte1 & PTE_V) == 0 ) return 1; |
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| 115 | |
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| 116 | // get physical addresses of pte2 (two 32 bits words) |
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| 117 | ptba = (unsigned long long) (pt->pt1[ix1] & 0x0FFFFFFF) << 12; |
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| 118 | pte2_paddr = ptba + 8*ix2; |
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| 119 | pte2_lsb = (unsigned int) pte2_paddr; |
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| 120 | pte2_msb = (unsigned int) (pte2_paddr >> 32); |
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| 121 | |
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| 122 | // gets ppn_value and flags_value, after temporary DTLB desactivation |
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| 123 | asm volatile ( |
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| 124 | "li $2, 0xFFFFFFFE \n" /* Mask for IE bits */ |
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| 125 | "mfc0 $4, $12 \n" /* $4 <= SR */ |
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| 126 | "and $2, $2, $4 \n" |
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| 127 | "mtc0 $2, $12 \n" /* disable Interrupts */ |
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| 128 | |
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| 129 | "li $3, 0xB \n" |
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| 130 | "mtc2 $3, $1 \n" /* DTLB unactivated */ |
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| 131 | |
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| 132 | "mtc2 %2, $24 \n" /* PADDR_EXT <= msb */ |
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| 133 | "lw %0, 0(%3) \n" /* read flags */ |
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| 134 | "lw %1, 4(%3) \n" /* read ppn */ |
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| 135 | "mtc2 $0, $24 \n" /* PADDR_EXT <= 0 */ |
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| 136 | |
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| 137 | "li $3, 0xF \n" |
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| 138 | "mtc2 $3, $1 \n" /* DTLB activated */ |
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| 139 | |
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| 140 | "mtc0 $4, $12 \n" /* restore SR */ |
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| 141 | : "=r" (flags_value), "=r" (ppn_value) |
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| 142 | : "r" (pte2_msb), "r" (pte2_lsb) |
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| 143 | : "$2","$3","$4"); |
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| 144 | |
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| 145 | // check PTE2 mapping |
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| 146 | if ( (flags_value & PTE_V) == 0 ) return 1; |
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| 147 | |
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| 148 | // set return values |
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| 149 | *ppn = ppn_value; |
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| 150 | *flags = flags_value; |
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| 151 | return 0; |
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| 152 | } // end _v2p_translate() |
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| 153 | |
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| 154 | |
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| 155 | |
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| 156 | // Local Variables: |
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| 157 | // tab-width: 4 |
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| 158 | // c-basic-offset: 4 |
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| 159 | // c-file-offsets:((innamespace . 0)(inline-open . 0)) |
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| 160 | // indent-tabs-mode: nil |
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| 161 | // End: |
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| 162 | // vim: filetype=c:expandtab:shiftwidth=4:tabstop=4:softtabstop=4 |
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| 163 | |
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| 164 | |
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