arch/parisc/kernel/real2.S

   1 /*
   2  *
   3  * This file is subject to the terms and conditions of the GNU General Public
   4  * License.  See the file "COPYING" in the main directory of this archive
   5  * for more details.
   6  *
   7  * Copyright (C) 2000 Hewlett Packard (Paul Bame bame@puffin.external.hp.com)
   8  *
   9  */
  10 #include <asm/assembly.h>
  11 #include <asm/psw.h>
  12
  13         .section        .bss
  14         .export real_stack
  15         .export real32_stack
  16         .export real64_stack
  17         .align  64
  18 real_stack:
  19 real32_stack:
  20 real64_stack:
  21         .block  8192
  22
  23 #ifdef __LP64__
  24 #  define REG_SZ 8
  25 #else
  26 #  define REG_SZ 4
  27 #endif
  28
  29 #define N_SAVED_REGS 9
  30
  31 save_cr_space:
  32         .block  REG_SZ * N_SAVED_REGS
  33 save_cr_end:
  34
  35
  36 /************************ 32-bit real-mode calls ***********************/
  37 /* This can be called in both narrow and wide kernels */
  38
  39         .text
  40
  41         .export real32_call_asm
  42
  43         /* unsigned long real32_call_asm(unsigned int *sp,
  44          *              unsigned int *arg0p,
  45          *              unsigned int iodc_fn)
  46          *      sp is value of stack pointer to adopt before calling PDC (virt)
  47          *      arg0p points to where saved arg values may be found
  48          *      iodc_fn is the IODC function to call
  49          */
  50
  51 real32_call_asm:
  52         STREG   %rp, -RP_OFFSET(%sp)    /* save RP */
  53 #ifdef __LP64__
  54         callee_save
  55         ldo     2*REG_SZ(%sp), %sp      /* room for a couple more saves */
  56         STREG   %r27, -1*REG_SZ(%sp)
  57         STREG   %r29, -2*REG_SZ(%sp)
  58 #endif
  59         STREG   %sp, -REG_SZ(%arg0)     /* save SP on real-mode stack */
  60         copy    %arg0, %sp              /* adopt the real-mode SP */
  61
  62         /* save iodc_fn */
  63         copy    %arg2, %r31
  64
  65         /* load up the arg registers from the saved arg area */
  66         /* 32-bit calling convention passes first 4 args in registers */
  67         ldw     0(%arg1), %arg0         /* note overwriting arg0 */
  68         ldw     -8(%arg1), %arg2
  69         ldw     -12(%arg1), %arg3
  70         ldw     -4(%arg1), %arg1        /* obviously must do this one last! */
  71
  72         tophys_r1  %sp
  73
  74         b,l     rfi_virt2real,%r2
  75         nop
  76
  77         b,l     save_control_regs,%r2           /* modifies r1, r2, r28 */
  78         nop
  79
  80 #ifdef __LP64__
  81         rsm     PSW_SM_W, %r0           /* go narrow */
  82 #endif
  83
  84         load32  PA(ric_ret), %r2
  85         bv      0(%r31)
  86         nop
  87 ric_ret:
  88 #ifdef __LP64__
  89         ssm     PSW_SM_W, %r0           /* go wide */
  90 #endif
  91         /* restore CRs before going virtual in case we page fault */
  92         b,l     restore_control_regs, %r2       /* modifies r1, r2, r26 */
  93         nop
  94
  95         b,l     rfi_real2virt,%r2
  96         nop
  97
  98         tovirt_r1 %sp
  99         LDREG   -REG_SZ(%sp), %sp       /* restore SP */
 100 #ifdef __LP64__
 101         LDREG   -1*REG_SZ(%sp), %r27
 102         LDREG   -2*REG_SZ(%sp), %r29
 103         ldo     -2*REG_SZ(%sp), %sp
 104         callee_rest
 105 #endif
 106         LDREG   -RP_OFFSET(%sp), %rp    /* restore RP */
 107         bv      0(%rp)
 108         nop
 109
 110
 111 #  define PUSH_CR(r, where) mfctl r, %r1 ! STREG,ma %r1, REG_SZ(where)
 112 #  define POP_CR(r, where) LDREG,mb -REG_SZ(where), %r1 ! mtctl %r1, r
 113
 114         .text
 115 save_control_regs:
 116         load32  PA(save_cr_space), %r28
 117         PUSH_CR(%cr24, %r28)
 118         PUSH_CR(%cr25, %r28)
 119         PUSH_CR(%cr26, %r28)
 120         PUSH_CR(%cr27, %r28)
 121         PUSH_CR(%cr28, %r28)
 122         PUSH_CR(%cr29, %r28)
 123         PUSH_CR(%cr30, %r28)
 124         PUSH_CR(%cr31, %r28)
 125         PUSH_CR(%cr15, %r28)
 126         bv 0(%r2)
 127         nop
 128
 129 restore_control_regs:
 130         load32  PA(save_cr_end), %r26
 131         POP_CR(%cr15, %r26)
 132         POP_CR(%cr31, %r26)
 133         POP_CR(%cr30, %r26)
 134         POP_CR(%cr29, %r26)
 135         POP_CR(%cr28, %r26)
 136         POP_CR(%cr27, %r26)
 137         POP_CR(%cr26, %r26)
 138         POP_CR(%cr25, %r26)
 139         POP_CR(%cr24, %r26)
 140         bv 0(%r2)
 141         nop
 142
 143 /* rfi_virt2real() and rfi_real2virt() could perhaps be adapted for
 144  * more general-purpose use by the several places which need RFIs
 145  */
 146         .align 128
 147         .text
 148 rfi_virt2real:
 149         /* switch to real mode... */
 150         ssm             0,0             /* See "relied upon translation" */
 151         nop                             /* PA 2.0 Arch. F-5 */
 152         nop
 153         nop
 154         nop
 155         nop
 156         nop
 157         nop
 158         nop
 159
 160         rsm             (PSW_SM_Q|PSW_SM_I),%r0  /* disable Q & I bits to load iia queue */
 161         mtctl           %r0, %cr17      /* Clear IIASQ tail */
 162         mtctl           %r0, %cr17      /* Clear IIASQ head */
 163         load32          PA(rfi_v2r_1), %r1
 164         mtctl           %r1, %cr18      /* IIAOQ head */
 165         ldo             4(%r1), %r1
 166         mtctl           %r1, %cr18      /* IIAOQ tail */
 167         load32          REAL_MODE_PSW, %r1
 168         mtctl           %r1, %cr22
 169         rfi
 170
 171         nop
 172         nop
 173         nop
 174         nop
 175         nop
 176         nop
 177         nop
 178         nop
 179 rfi_v2r_1:
 180         tophys_r1 %r2
 181         bv      0(%r2)
 182         nop
 183
 184         .text
 185         .align 128
 186 rfi_real2virt:
 187         ssm             0,0             /* See "relied upon translation" */
 188         nop                             /* PA 2.0 Arch. F-5 */
 189         nop
 190         nop
 191         nop
 192         nop
 193         nop
 194         nop
 195         nop
 196
 197         rsm             PSW_SM_Q,%r0    /* disable Q bit to load iia queue */
 198         mtctl           %r0, %cr17      /* Clear IIASQ tail */
 199         mtctl           %r0, %cr17      /* Clear IIASQ head */
 200         load32          (rfi_r2v_1), %r1
 201         mtctl           %r1, %cr18      /* IIAOQ head */
 202         ldo             4(%r1), %r1
 203         mtctl           %r1, %cr18      /* IIAOQ tail */
 204         load32          KERNEL_PSW, %r1
 205         mtctl           %r1, %cr22
 206         rfi
 207
 208         nop
 209         nop
 210         nop
 211         nop
 212         nop
 213         nop
 214         nop
 215         nop
 216 rfi_r2v_1:
 217         tovirt_r1 %r2
 218         bv      0(%r2)
 219         nop
 220
 221 #ifdef __LP64__
 222
 223 /************************ 64-bit real-mode calls ***********************/
 224 /* This is only usable in wide kernels right now and will probably stay so */
 225         .text
 226         .export real64_call_asm
 227         /* unsigned long real64_call_asm(unsigned long *sp,
 228          *              unsigned long *arg0p,
 229          *              unsigned long fn)
 230          *      sp is value of stack pointer to adopt before calling PDC (virt)
 231          *      arg0p points to where saved arg values may be found
 232          *      iodc_fn is the IODC function to call
 233          */
 234 real64_call_asm:
 235         std     %rp, -0x10(%sp)         /* save RP */
 236         std     %sp, -8(%arg0)          /* save SP on real-mode stack */
 237         copy    %arg0, %sp              /* adopt the real-mode SP */
 238
 239         /* save fn */
 240         copy    %arg2, %r31
 241
 242         /* set up the new ap */
 243         ldo     64(%arg1), %r29
 244
 245         /* load up the arg registers from the saved arg area */
 246         /* 32-bit calling convention passes first 4 args in registers */
 247         ldd     0*REG_SZ(%arg1), %arg0          /* note overwriting arg0 */
 248         ldd     2*REG_SZ(%arg1), %arg2
 249         ldd     3*REG_SZ(%arg1), %arg3
 250         ldd     4*REG_SZ(%arg1), %r22
 251         ldd     5*REG_SZ(%arg1), %r21
 252         ldd     6*REG_SZ(%arg1), %r20
 253         ldd     7*REG_SZ(%arg1), %r19
 254         ldd     1*REG_SZ(%arg1), %arg1          /* do this one last! */
 255
 256         tophys_r1 %sp
 257
 258         b,l     rfi_virt2real,%r2
 259         nop
 260
 261         b,l     save_control_regs,%r2           /* modifies r1, r2, r28 */
 262         nop
 263
 264         load32  PA(r64_ret), %r2
 265         bv      0(%r31)
 266         nop
 267 r64_ret:
 268         /* restore CRs before going virtual in case we page fault */
 269         b,l     restore_control_regs, %r2       /* modifies r1, r2, r26 */
 270         nop
 271
 272         b,l     rfi_real2virt,%r2
 273         nop
 274
 275         tovirt_r1 %sp
 276         ldd     -8(%sp), %sp            /* restore SP */
 277         ldd     -0x10(%sp), %rp         /* restore RP */
 278         bv      0(%rp)
 279         nop
 280
 281 #endif
 282
 283         .export pc_in_user_space
 284         .text
 285         /* Doesn't belong here but I couldn't find a nicer spot. */
 286         /* Should never get called, only used by profile stuff in time.c */
 287 pc_in_user_space:
 288         bv,n    0(%rp)
 289         nop
 290
 291
 292         .export __canonicalize_funcptr_for_compare
 293         .text
 294         /* http://lists.parisc-linux.org/hypermail/parisc-linux/10916.html
 295         **      GCC 3.3 and later has a new function in libgcc.a for
 296         **      comparing function pointers.
 297         */
 298 __canonicalize_funcptr_for_compare:
 299 #ifdef __LP64__
 300         bve (%r2)
 301 #else
 302         bv %r0(%r2)
 303 #endif
 304         copy %r26,%r28