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 11#include <asm/psw.h> 12#include <asm/assembly.h> 13 14#include <linux/linkage.h> 15 16 .section .bss 17 .export real_stack 18 .export real32_stack 19 .export real64_stack 20 .align 64 21real_stack: 22real32_stack: 23real64_stack: 24 .block 8192 25 26#ifdef CONFIG_64BIT 27# define REG_SZ 8 28#else 29# define REG_SZ 4 30#endif 31 32#define N_SAVED_REGS 9 33 34save_cr_space: 35 .block REG_SZ * N_SAVED_REGS 36save_cr_end: 37 38 39/************************ 32-bit real-mode calls ***********************/ 40/* This can be called in both narrow and wide kernels */ 41 42 .text 43 44 /* unsigned long real32_call_asm(unsigned int *sp, 45 * unsigned int *arg0p, 46 * unsigned int iodc_fn) 47 * sp is value of stack pointer to adopt before calling PDC (virt) 48 * arg0p points to where saved arg values may be found 49 * iodc_fn is the IODC function to call 50 */ 51 52ENTRY(real32_call_asm) 53 STREG %rp, -RP_OFFSET(%sp) /* save RP */ 54#ifdef CONFIG_64BIT 55 callee_save 56 ldo 2*REG_SZ(%sp), %sp /* room for a couple more saves */ 57 STREG %r27, -1*REG_SZ(%sp) 58 STREG %r29, -2*REG_SZ(%sp) 59#endif 60 STREG %sp, -REG_SZ(%arg0) /* save SP on real-mode stack */ 61 copy %arg0, %sp /* adopt the real-mode SP */ 62 63 /* save iodc_fn */ 64 copy %arg2, %r31 65 66 /* load up the arg registers from the saved arg area */ 67 /* 32-bit calling convention passes first 4 args in registers */ 68 ldw 0(%arg1), %arg0 /* note overwriting arg0 */ 69 ldw -8(%arg1), %arg2 70 ldw -12(%arg1), %arg3 71 ldw -4(%arg1), %arg1 /* obviously must do this one last! */ 72 73 tophys_r1 %sp 74 75 b,l rfi_virt2real,%r2 76 nop 77 78 b,l save_control_regs,%r2 /* modifies r1, r2, r28 */ 79 nop 80 81#ifdef CONFIG_64BIT 82 rsm PSW_SM_W, %r0 /* go narrow */ 83#endif 84 85 load32 PA(ric_ret), %r2 86 bv 0(%r31) 87 nop 88ric_ret: 89#ifdef CONFIG_64BIT 90 ssm PSW_SM_W, %r0 /* go wide */ 91#endif 92 /* restore CRs before going virtual in case we page fault */ 93 b,l restore_control_regs, %r2 /* modifies r1, r2, r26 */ 94 nop 95 96 b,l rfi_real2virt,%r2 97 nop 98 99 tovirt_r1 %sp 100 LDREG -REG_SZ(%sp), %sp /* restore SP */ 101#ifdef CONFIG_64BIT 102 LDREG -1*REG_SZ(%sp), %r27 103 LDREG -2*REG_SZ(%sp), %r29 104 ldo -2*REG_SZ(%sp), %sp 105 callee_rest 106#endif 107 LDREG -RP_OFFSET(%sp), %rp /* restore RP */ 108 bv 0(%rp) 109 nop 110ENDPROC(real32_call_asm) 111 112 113# define PUSH_CR(r, where) mfctl r, %r1 ! STREG,ma %r1, REG_SZ(where) 114# define POP_CR(r, where) LDREG,mb -REG_SZ(where), %r1 ! mtctl %r1, r 115 116 .text 117save_control_regs: 118 load32 PA(save_cr_space), %r28 119 PUSH_CR(%cr24, %r28) 120 PUSH_CR(%cr25, %r28) 121 PUSH_CR(%cr26, %r28) 122 PUSH_CR(%cr27, %r28) 123 PUSH_CR(%cr28, %r28) 124 PUSH_CR(%cr29, %r28) 125 PUSH_CR(%cr30, %r28) 126 PUSH_CR(%cr31, %r28) 127 PUSH_CR(%cr15, %r28) 128 bv 0(%r2) 129 nop 130 131restore_control_regs: 132 load32 PA(save_cr_end), %r26 133 POP_CR(%cr15, %r26) 134 POP_CR(%cr31, %r26) 135 POP_CR(%cr30, %r26) 136 POP_CR(%cr29, %r26) 137 POP_CR(%cr28, %r26) 138 POP_CR(%cr27, %r26) 139 POP_CR(%cr26, %r26) 140 POP_CR(%cr25, %r26) 141 POP_CR(%cr24, %r26) 142 bv 0(%r2) 143 nop 144 145/* rfi_virt2real() and rfi_real2virt() could perhaps be adapted for 146 * more general-purpose use by the several places which need RFIs 147 */ 148 .text 149 .align 128 150rfi_virt2real: 151 /* switch to real mode... */ 152 rsm PSW_SM_I,%r0 153 load32 PA(rfi_v2r_1), %r1 154 nop 155 nop 156 nop 157 nop 158 nop 159 160 rsm PSW_SM_Q,%r0 /* disable Q & I bits to load iia queue */ 161 mtctl %r0, %cr17 /* Clear IIASQ tail */ 162 mtctl %r0, %cr17 /* Clear IIASQ head */ 163 mtctl %r1, %cr18 /* IIAOQ head */ 164 ldo 4(%r1), %r1 165 mtctl %r1, %cr18 /* IIAOQ tail */ 166 load32 REAL_MODE_PSW, %r1 167 mtctl %r1, %cr22 168 rfi 169 170 nop 171 nop 172 nop 173 nop 174 nop 175 nop 176 nop 177 nop 178rfi_v2r_1: 179 tophys_r1 %r2 180 bv 0(%r2) 181 nop 182 183 .text 184 .align 128 185rfi_real2virt: 186 rsm PSW_SM_I,%r0 187 load32 (rfi_r2v_1), %r1 188 nop 189 nop 190 nop 191 nop 192 nop 193 194 rsm PSW_SM_Q,%r0 /* disable Q bit to load iia queue */ 195 mtctl %r0, %cr17 /* Clear IIASQ tail */ 196 mtctl %r0, %cr17 /* Clear IIASQ head */ 197 mtctl %r1, %cr18 /* IIAOQ head */ 198 ldo 4(%r1), %r1 199 mtctl %r1, %cr18 /* IIAOQ tail */ 200 load32 KERNEL_PSW, %r1 201 mtctl %r1, %cr22 202 rfi 203 204 nop 205 nop 206 nop 207 nop 208 nop 209 nop 210 nop 211 nop 212rfi_r2v_1: 213 tovirt_r1 %r2 214 bv 0(%r2) 215 nop 216 217#ifdef CONFIG_64BIT 218 219/************************ 64-bit real-mode calls ***********************/ 220/* This is only usable in wide kernels right now and will probably stay so */ 221 .text 222 /* unsigned long real64_call_asm(unsigned long *sp, 223 * unsigned long *arg0p, 224 * unsigned long fn) 225 * sp is value of stack pointer to adopt before calling PDC (virt) 226 * arg0p points to where saved arg values may be found 227 * iodc_fn is the IODC function to call 228 */ 229ENTRY(real64_call_asm) 230 std %rp, -0x10(%sp) /* save RP */ 231 std %sp, -8(%arg0) /* save SP on real-mode stack */ 232 copy %arg0, %sp /* adopt the real-mode SP */ 233 234 /* save fn */ 235 copy %arg2, %r31 236 237 /* set up the new ap */ 238 ldo 64(%arg1), %r29 239 240 /* load up the arg registers from the saved arg area */ 241 /* 32-bit calling convention passes first 4 args in registers */ 242 ldd 0*REG_SZ(%arg1), %arg0 /* note overwriting arg0 */ 243 ldd 2*REG_SZ(%arg1), %arg2 244 ldd 3*REG_SZ(%arg1), %arg3 245 ldd 4*REG_SZ(%arg1), %r22 246 ldd 5*REG_SZ(%arg1), %r21 247 ldd 6*REG_SZ(%arg1), %r20 248 ldd 7*REG_SZ(%arg1), %r19 249 ldd 1*REG_SZ(%arg1), %arg1 /* do this one last! */ 250 251 tophys_r1 %sp 252 253 b,l rfi_virt2real,%r2 254 nop 255 256 b,l save_control_regs,%r2 /* modifies r1, r2, r28 */ 257 nop 258 259 load32 PA(r64_ret), %r2 260 bv 0(%r31) 261 nop 262r64_ret: 263 /* restore CRs before going virtual in case we page fault */ 264 b,l restore_control_regs, %r2 /* modifies r1, r2, r26 */ 265 nop 266 267 b,l rfi_real2virt,%r2 268 nop 269 270 tovirt_r1 %sp 271 ldd -8(%sp), %sp /* restore SP */ 272 ldd -0x10(%sp), %rp /* restore RP */ 273 bv 0(%rp) 274 nop 275ENDPROC(real64_call_asm) 276 277#endif 278 279 .text 280 /* http://lists.parisc-linux.org/hypermail/parisc-linux/10916.html 281 ** GCC 3.3 and later has a new function in libgcc.a for 282 ** comparing function pointers. 283 */ 284ENTRY(__canonicalize_funcptr_for_compare) 285#ifdef CONFIG_64BIT 286 bve (%r2) 287#else 288 bv %r0(%r2) 289#endif 290 copy %r26,%r28 291ENDPROC(__canonicalize_funcptr_for_compare) 292 293