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