1 /* 1 /* 2 * Copyright (C) 2007-2009 Michal Simek <monstr << 3 * Copyright (C) 2007-2009 PetaLogix << 4 * Copyright (C) 2006 Atmark Techno, Inc. << 5 * << 6 * MMU code derived from arch/ppc/kernel/head_ << 7 * Copyright (c) 1995-1996 Gary Thomas <gdt@ << 8 * Initial PowerPC version. << 9 * Copyright (c) 1996 Cort Dougan <cort@cs.n << 10 * Rewritten for PReP << 11 * Copyright (c) 1996 Paul Mackerras <paulus << 12 * Low-level exception handers, MMU suppo << 13 * Copyright (c) 1997 Dan Malek <dmalek@jlc. << 14 * PowerPC 8xx modifications. << 15 * Copyright (c) 1998-1999 TiVo, Inc. << 16 * PowerPC 403GCX modifications. << 17 * Copyright (c) 1999 Grant Erickson <grant@ << 18 * PowerPC 403GCX/405GP modifications. << 19 * Copyright 2000 MontaVista Software Inc. << 20 * PPC405 modifications << 21 * PowerPC 403GCX/405GP modifications. << 22 * Author: MontaVista Software, Inc. << 23 * frank_rowand@mvista.com or sou << 24 * debbie_chu@mvista.com << 25 * << 26 * This file is subject to the terms and condi 2 * This file is subject to the terms and conditions of the GNU General Public 27 * License. See the file "COPYING" in the main !! 3 * License. See the file "COPYING" in the main directory of this archive 28 * for more details. 4 * for more details. >> 5 * >> 6 * Copyright (C) 1994, 1995 Waldorf Electronics >> 7 * Written by Ralf Baechle and Andreas Busse >> 8 * Copyright (C) 1994 - 99, 2003, 06 Ralf Baechle >> 9 * Copyright (C) 1996 Paul M. Antoine >> 10 * Modified for DECStation and hence R3000 support by Paul M. Antoine >> 11 * Further modifications by David S. Miller and Harald Koerfgen >> 12 * Copyright (C) 1999 Silicon Graphics, Inc. >> 13 * Kevin Kissell, kevink@mips.com and Carsten Langgaard, carstenl@mips.com >> 14 * Copyright (C) 2000 MIPS Technologies, Inc. All rights reserved. 29 */ 15 */ 30 << 31 #include <linux/init.h> 16 #include <linux/init.h> 32 #include <linux/linkage.h> !! 17 #include <linux/threads.h> 33 #include <asm/thread_info.h> !! 18 34 #include <asm/page.h> !! 19 #include <asm/addrspace.h> 35 #include <linux/of_fdt.h> /* for !! 20 #include <asm/asm.h> 36 !! 21 #include <asm/asmmacro.h> 37 #include <asm/setup.h> /* COMMAND_LINE_SIZE */ !! 22 #include <asm/irqflags.h> 38 #include <asm/mmu.h> !! 23 #include <asm/regdef.h> 39 #include <asm/processor.h> !! 24 #include <asm/pgtable-bits.h> 40 !! 25 #include <asm/mipsregs.h> 41 .section .data !! 26 #include <asm/stackframe.h> 42 .global empty_zero_page !! 27 43 .align 12 !! 28 #include <kernel-entry-init.h> 44 empty_zero_page: !! 29 45 .space PAGE_SIZE !! 30 /* 46 .global swapper_pg_dir !! 31 * inputs are the text nasid in t1, data nasid in t2. 47 swapper_pg_dir: !! 32 */ 48 .space PAGE_SIZE !! 33 .macro MAPPED_KERNEL_SETUP_TLB 49 !! 34 #ifdef CONFIG_MAPPED_KERNEL 50 .section .rodata !! 35 /* 51 .align 4 !! 36 * This needs to read the nasid - assume 0 for now. 52 endian_check: !! 37 * Drop in 0xffffffffc0000000 in tlbhi, 0+VG in tlblo_0, 53 .word 1 !! 38 * 0+DVG in tlblo_1. 54 !! 39 */ 55 __HEAD !! 40 dli t0, 0xffffffffc0000000 56 ENTRY(_start) !! 41 dmtc0 t0, CP0_ENTRYHI 57 #if CONFIG_KERNEL_BASE_ADDR == 0 !! 42 li t0, 0x1c000 # Offset of text into node memory 58 brai TOPHYS(real_start) !! 43 dsll t1, NASID_SHFT # Shift text nasid into place 59 .org 0x100 !! 44 dsll t2, NASID_SHFT # Same for data nasid 60 real_start: !! 45 or t1, t1, t0 # Physical load address of kernel text >> 46 or t2, t2, t0 # Physical load address of kernel data >> 47 dsrl t1, 12 # 4K pfn >> 48 dsrl t2, 12 # 4K pfn >> 49 dsll t1, 6 # Get pfn into place >> 50 dsll t2, 6 # Get pfn into place >> 51 li t0, ((_PAGE_GLOBAL|_PAGE_VALID| _CACHE_CACHABLE_COW) >> 6) >> 52 or t0, t0, t1 >> 53 mtc0 t0, CP0_ENTRYLO0 # physaddr, VG, cach exlwr >> 54 li t0, ((_PAGE_GLOBAL|_PAGE_VALID| _PAGE_DIRTY|_CACHE_CACHABLE_COW) >> 6) >> 55 or t0, t0, t2 >> 56 mtc0 t0, CP0_ENTRYLO1 # physaddr, DVG, cach exlwr >> 57 li t0, 0x1ffe000 # MAPPED_KERN_TLBMASK, TLBPGMASK_16M >> 58 mtc0 t0, CP0_PAGEMASK >> 59 li t0, 0 # KMAP_INX >> 60 mtc0 t0, CP0_INDEX >> 61 li t0, 1 >> 62 mtc0 t0, CP0_WIRED >> 63 tlbwi >> 64 #else >> 65 mtc0 zero, CP0_WIRED 61 #endif 66 #endif >> 67 .endm 62 68 63 mts rmsr, r0 !! 69 /* 64 /* Disable stack protection from bootloader */ !! 70 * For the moment disable interrupts, mark the kernel mode and 65 mts rslr, r0 !! 71 * set ST0_KX so that the CPU does not spit fire when using 66 addi r8, r0, 0xFFFFFFFF !! 72 * 64-bit addresses. A full initialization of the CPU's status 67 mts rshr, r8 !! 73 * register is done later in per_cpu_trap_init(). 68 /* !! 74 */ 69 * According to Xilinx, msrclr instruction beh !! 75 .macro setup_c0_status set clr 70 * if the msrclr instruction is not enabled. W !! 76 .set push 71 * if the opcode is available, by issuing msrc !! 77 #ifdef CONFIG_MIPS_MT_SMTC 72 * r8 == 0 - msr instructions are implemented !! 78 /* 73 * r8 != 0 - msr instructions are not implemen !! 79 * For SMTC, we need to set privilege and disable interrupts only for 74 */ !! 80 * the current TC, using the TCStatus register. 75 mfs r1, rmsr !! 81 */ 76 msrclr r8, 0 /* clear nothing - just !! 82 mfc0 t0, CP0_TCSTATUS 77 cmpu r8, r8, r1 /* r1 must contain !! 83 /* Fortunately CU 0 is in the same place in both registers */ 78 !! 84 /* Set TCU0, TMX, TKSU (for later inversion) and IXMT */ 79 /* r7 may point to an FDT, or there may be one !! 85 li t1, ST0_CU0 | 0x08001c00 80 if it's in r7, we've got to save it away AS !! 86 or t0, t1 81 We ensure r7 points to a valid FDT, just in !! 87 /* Clear TKSU, leave IXMT */ 82 is broken or non-existent */ !! 88 xori t0, 0x00001800 83 beqi r7, no_fdt_arg !! 89 mtc0 t0, CP0_TCSTATUS 84 /* Does r7 point to a valid FDT? Load HEADER m !! 90 _ehb 85 /* Run time Big/Little endian platform !! 91 /* We need to leave the global IE bit set, but clear EXL...*/ 86 /* Save 1 as word and load byte - 0 - !! 92 mfc0 t0, CP0_STATUS 87 lbui r11, r0, TOPHYS(endian_check) !! 93 or t0, ST0_CU0 | ST0_EXL | ST0_ERL | \set | \clr 88 beqid r11, big_endian /* DO NOT brea !! 94 xor t0, ST0_EXL | ST0_ERL | \clr 89 lw r11, r0, r7 /* Big endian load !! 95 mtc0 t0, CP0_STATUS 90 lwr r11, r0, r7 /* Little endian l !! 96 #else 91 big_endian: !! 97 mfc0 t0, CP0_STATUS 92 rsubi r11, r11, OF_DT_HEADER /* Che !! 98 or t0, ST0_CU0|\set|0x1f|\clr 93 beqi r11, _prepare_copy_fdt !! 99 xor t0, 0x1f|\clr 94 or r7, r0, r0 /* cle !! 100 mtc0 t0, CP0_STATUS 95 bnei r11, no_fdt_arg !! 101 .set noreorder 96 _prepare_copy_fdt: !! 102 sll zero,3 # ehb 97 or r11, r0, r0 /* incremment */ !! 103 #endif 98 ori r4, r0, TOPHYS(_fdt_start) !! 104 .set pop 99 ori r3, r0, (0x10000 - 4) !! 105 .endm 100 _copy_fdt: << 101 lw r12, r7, r11 /* r12 = r7 + r11 << 102 sw r12, r4, r11 /* addr[r4 + r11] << 103 addik r11, r11, 4 /* increment count << 104 bgtid r3, _copy_fdt /* loop for all << 105 addik r3, r3, -4 /* descrement loop << 106 no_fdt_arg: << 107 106 108 #ifndef CONFIG_CMDLINE_BOOL !! 107 .macro setup_c0_status_pri 109 /* !! 108 #ifdef CONFIG_64BIT 110 * handling command line !! 109 setup_c0_status ST0_KX 0 111 * copy command line directly to cmd_line plac !! 110 #else 112 */ !! 111 setup_c0_status 0 0 113 beqid r5, skip /* Skip if NUL << 114 or r11, r0, r0 /* inc << 115 ori r4, r0, cmd_line /* loa << 116 tophys(r4,r4) /* con << 117 ori r3, r0, COMMAND_LINE_SIZE - 1 << 118 _copy_command_line: << 119 /* r2=r5+r11 - r5 contain pointer to c << 120 lbu r2, r5, r11 << 121 beqid r2, skip /* Ski << 122 sb r2, r4, r11 /* add << 123 addik r11, r11, 1 /* inc << 124 bgtid r3, _copy_command_line /* loo << 125 addik r3, r3, -1 /* dec << 126 addik r5, r4, 0 /* add << 127 tovirt(r5,r5) << 128 skip: << 129 #endif /* CONFIG_CMDLINE_BOOL */ << 130 << 131 #ifdef NOT_COMPILE << 132 /* save bram context */ << 133 or r11, r0, r0 << 134 ori r4, r0, TOPHYS(_bram_load_star << 135 ori r3, r0, (LMB_SIZE - 4) << 136 _copy_bram: << 137 lw r7, r0, r11 /* r7 << 138 sw r7, r4, r11 /* add << 139 addik r11, r11, 4 /* inc << 140 bgtid r3, _copy_bram /* loo << 141 addik r3, r3, -4 /* des << 142 #endif 112 #endif 143 /* We have to turn on the MMU right aw !! 113 .endm 144 114 145 /* !! 115 .macro setup_c0_status_sec 146 * Set up the initial MMU state so we !! 116 #ifdef CONFIG_64BIT 147 * kernel initialization. This maps t !! 117 setup_c0_status ST0_KX ST0_BEV 148 * virtual to physical. !! 118 #else 149 */ !! 119 setup_c0_status 0 ST0_BEV 150 nop !! 120 #endif 151 addik r3, r0, MICROBLAZE_TLB_SIZE -1 !! 121 .endm 152 _invalidate: << 153 mts rtlbx, r3 << 154 mts rtlbhi, r0 << 155 mts rtlblo, r0 << 156 bgtid r3, _invalidate /* loo << 157 addik r3, r3, -1 << 158 /* sync */ << 159 << 160 /* Setup the kernel PID */ << 161 mts rpid,r0 /* Loa << 162 nop << 163 bri 4 << 164 122 >> 123 #ifndef CONFIG_NO_EXCEPT_FILL 165 /* 124 /* 166 * We should still be executing code a !! 125 * Reserved space for exception handlers. 167 * RAM_BASEADDR at this point. However !! 126 * Necessary for machines which link their kernels at KSEG0. 168 * a virtual address. So, set up a TLB << 169 * translation is enabled. << 170 */ 127 */ >> 128 .fill 0x400 >> 129 #endif 171 130 172 addik r3,r0, CONFIG_KERNEL_START /* !! 131 EXPORT(_stext) 173 tophys(r4,r3) /* Loa << 174 << 175 /* start to do TLB calculation */ << 176 addik r12, r0, _end << 177 rsub r12, r3, r12 << 178 addik r12, r12, CONFIG_LOWMEM_SIZE > << 179 << 180 or r9, r0, r0 /* TLB0 = 0 */ << 181 or r10, r0, r0 /* TLB1 = 0 */ << 182 << 183 addik r11, r12, -0x1000000 << 184 bgei r11, GT16 /* size is greater t << 185 addik r11, r12, -0x0800000 << 186 bgei r11, GT8 /* size is greater th << 187 addik r11, r12, -0x0400000 << 188 bgei r11, GT4 /* size is greater th << 189 /* size is less than 4MB */ << 190 addik r11, r12, -0x0200000 << 191 bgei r11, GT2 /* size is greater th << 192 addik r9, r0, 0x0100000 /* TLB0 must << 193 addik r11, r12, -0x0100000 << 194 bgei r11, GT1 /* size is greater th << 195 /* TLB1 is 0 which is setup above */ << 196 bri tlb_end << 197 GT4: /* r11 contains the rest - will be either << 198 ori r9, r0, 0x400000 /* TLB0 is 4MB */ << 199 bri TLB1 << 200 GT16: /* TLB0 is 16MB */ << 201 addik r9, r0, 0x1000000 /* means TLB << 202 TLB1: << 203 /* must be used r2 because of subtract << 204 addik r2, r11, -0x0400000 << 205 bgei r2, GT20 /* size is greater th << 206 /* size is >16MB and <20MB */ << 207 addik r11, r11, -0x0100000 << 208 bgei r11, GT17 /* size is greater t << 209 /* kernel is >16MB and < 17MB */ << 210 GT1: << 211 addik r10, r0, 0x0100000 /* means TL << 212 bri tlb_end << 213 GT2: /* TLB0 is 0 and TLB1 will be 4MB */ << 214 GT17: /* TLB1 is 4MB - kernel size <20MB */ << 215 addik r10, r0, 0x0400000 /* means TL << 216 bri tlb_end << 217 GT8: /* TLB0 is still zero that's why I can us << 218 GT20: /* TLB1 is 16MB - kernel size >20MB */ << 219 addik r10, r0, 0x1000000 /* means TL << 220 tlb_end: << 221 132 >> 133 #ifdef CONFIG_BOOT_RAW 222 /* 134 /* 223 * Configure and load two entries into !! 135 * Give us a fighting chance of running if execution beings at the 224 * In case we are pinning TLBs, these !! 136 * kernel load address. This is needed because this platform does 225 * other TLB functions. If not reserv !! 137 * not have a ELF loader yet. 226 * matter where they are loaded. << 227 */ 138 */ 228 andi r4,r4,0xfffffc00 /* Mas !! 139 FEXPORT(__kernel_entry) 229 ori r4,r4,(TLB_WR | TLB_EX) /* Set !! 140 j kernel_entry >> 141 #endif 230 142 231 /* !! 143 __REF 232 * TLB0 is always used - check if is n << 233 * if is use TLB1 value and clear it ( << 234 */ << 235 bnei r9, tlb0_not_zero << 236 add r9, r10, r0 << 237 add r10, r0, r0 << 238 tlb0_not_zero: << 239 << 240 /* look at the code below */ << 241 ori r30, r0, 0x200 << 242 andi r29, r9, 0x100000 << 243 bneid r29, 1f << 244 addik r30, r30, 0x80 << 245 andi r29, r9, 0x400000 << 246 bneid r29, 1f << 247 addik r30, r30, 0x80 << 248 andi r29, r9, 0x1000000 << 249 bneid r29, 1f << 250 addik r30, r30, 0x80 << 251 1: << 252 andi r3,r3,0xfffffc00 /* Mas << 253 ori r3,r3,(TLB_VALID) << 254 or r3, r3, r30 << 255 << 256 /* Load tlb_skip size value which is i << 257 lwi r11, r0, TOPHYS(tlb_skip) << 258 mts rtlbx,r11 /* TLB << 259 << 260 mts rtlblo,r4 /* Loa << 261 mts rtlbhi,r3 /* Loa << 262 << 263 /* Increase tlb_skip size */ << 264 addik r11, r11, 1 << 265 swi r11, r0, TOPHYS(tlb_skip) << 266 << 267 /* TLB1 can be zeroes that's why we no << 268 beqi r10, jump_over2 << 269 << 270 /* look at the code below */ << 271 ori r30, r0, 0x200 << 272 andi r29, r10, 0x100000 << 273 bneid r29, 1f << 274 addik r30, r30, 0x80 << 275 andi r29, r10, 0x400000 << 276 bneid r29, 1f << 277 addik r30, r30, 0x80 << 278 andi r29, r10, 0x1000000 << 279 bneid r29, 1f << 280 addik r30, r30, 0x80 << 281 1: << 282 addk r4, r4, r9 /* previous ad << 283 addk r3, r3, r9 << 284 144 285 andi r3,r3,0xfffffc00 /* Mas !! 145 NESTED(kernel_entry, 16, sp) # kernel entry point 286 ori r3,r3,(TLB_VALID) << 287 or r3, r3, r30 << 288 146 289 lwi r11, r0, TOPHYS(tlb_skip) !! 147 kernel_entry_setup # cpu specific setup 290 mts rtlbx, r11 /* r11 << 291 148 292 mts rtlblo,r4 /* Loa !! 149 setup_c0_status_pri 293 mts rtlbhi,r3 /* Loa << 294 150 295 /* Increase tlb_skip size */ !! 151 /* We might not get launched at the address the kernel is linked to, 296 addik r11, r11, 1 !! 152 so we jump there. */ 297 swi r11, r0, TOPHYS(tlb_skip) !! 153 PTR_LA t0, 0f >> 154 jr t0 >> 155 0: 298 156 299 jump_over2: !! 157 #ifdef CONFIG_MIPS_MT_SMTC 300 /* 158 /* 301 * Load a TLB entry for LMB, since we !! 159 * In SMTC kernel, "CLI" is thread-specific, in TCStatus. 302 * the exception vectors, using a 4k r !! 160 * We still need to enable interrupts globally in Status, >> 161 * and clear EXL/ERL. >> 162 * >> 163 * TCContext is used to track interrupt levels under >> 164 * service in SMTC kernel. Clear for boot TC before >> 165 * allowing any interrupts. 303 */ 166 */ 304 /* Use temporary TLB_ID for LMB - clea !! 167 mtc0 zero, CP0_TCCONTEXT 305 ori r11, r0, MICROBLAZE_LMB_TLB_ID !! 168 306 mts rtlbx,r11 !! 169 mfc0 t0, CP0_STATUS >> 170 ori t0, t0, 0xff1f >> 171 xori t0, t0, 0x001e >> 172 mtc0 t0, CP0_STATUS >> 173 #endif /* CONFIG_MIPS_MT_SMTC */ 307 174 308 ori r4,r0,(TLB_WR | TLB_EX) !! 175 PTR_LA t0, __bss_start # clear .bss 309 ori r3,r0,(TLB_VALID | TLB_PAGESZ( !! 176 LONG_S zero, (t0) >> 177 PTR_LA t1, __bss_stop - LONGSIZE >> 178 1: >> 179 PTR_ADDIU t0, LONGSIZE >> 180 LONG_S zero, (t0) >> 181 bne t0, t1, 1b >> 182 >> 183 LONG_S a0, fw_arg0 # firmware arguments >> 184 LONG_S a1, fw_arg1 >> 185 LONG_S a2, fw_arg2 >> 186 LONG_S a3, fw_arg3 >> 187 >> 188 MTC0 zero, CP0_CONTEXT # clear context register >> 189 PTR_LA $28, init_thread_union >> 190 /* Set the SP after an empty pt_regs. */ >> 191 PTR_LI sp, _THREAD_SIZE - 32 - PT_SIZE >> 192 PTR_ADDU sp, $28 >> 193 back_to_back_c0_hazard >> 194 set_saved_sp sp, t0, t1 >> 195 PTR_SUBU sp, 4 * SZREG # init stack pointer 310 196 311 mts rtlblo,r4 /* Loa !! 197 j start_kernel 312 mts rtlbhi,r3 /* Loa !! 198 END(kernel_entry) 313 199 314 /* !! 200 __CPUINIT 315 * We now have the lower 16 Meg of RAM << 316 * caches ready to work. << 317 */ << 318 turn_on_mmu: << 319 ori r15,r0,start_here << 320 ori r4,r0,MSR_KERNEL_VMS << 321 mts rmsr,r4 << 322 nop << 323 rted r15,0 /* ena << 324 nop << 325 << 326 start_here: << 327 << 328 /* Initialize small data anchors */ << 329 addik r13, r0, _KERNEL_SDA_BASE_ << 330 addik r2, r0, _KERNEL_SDA2_BASE_ << 331 << 332 /* Initialize stack pointer */ << 333 addik r1, r0, init_thread_union + TH << 334 << 335 /* Initialize r31 with current task ad << 336 addik r31, r0, init_task << 337 << 338 addik r11, r0, machine_early_init << 339 brald r15, r11 << 340 nop << 341 201 >> 202 #ifdef CONFIG_SMP >> 203 /* >> 204 * SMP slave cpus entry point. Board specific code for bootstrap calls this >> 205 * function after setting up the stack and gp registers. >> 206 */ >> 207 NESTED(smp_bootstrap, 16, sp) >> 208 #ifdef CONFIG_MIPS_MT_SMTC 342 /* 209 /* 343 * Initialize the MMU. !! 210 * Read-modify-writes of Status must be atomic, and this 344 */ !! 211 * is one case where CLI is invoked without EXL being 345 bralid r15, mmu_init !! 212 * necessarily set. The CLI and setup_c0_status will 346 nop !! 213 * in fact be redundant for all but the first TC of >> 214 * each VPE being booted. >> 215 */ >> 216 DMT 10 # dmt t2 /* t0, t1 are used by CLI and setup_c0_status() */ >> 217 jal mips_ihb >> 218 #endif /* CONFIG_MIPS_MT_SMTC */ >> 219 setup_c0_status_sec >> 220 smp_slave_setup >> 221 #ifdef CONFIG_MIPS_MT_SMTC >> 222 andi t2, t2, VPECONTROL_TE >> 223 beqz t2, 2f >> 224 EMT # emt >> 225 2: >> 226 #endif /* CONFIG_MIPS_MT_SMTC */ >> 227 j start_secondary >> 228 END(smp_bootstrap) >> 229 #endif /* CONFIG_SMP */ 347 230 348 /* Go back to running unmapped so we c !! 231 __FINIT 349 * and change to using our exception v << 350 * On the MicroBlaze, all we invalidat << 351 * the old 16M byte TLB mappings. << 352 */ << 353 ori r15,r0,TOPHYS(kernel_load_cont << 354 ori r4,r0,MSR_KERNEL << 355 mts rmsr,r4 << 356 nop << 357 bri 4 << 358 rted r15,0 << 359 nop << 360 << 361 /* Load up the kernel context */ << 362 kernel_load_context: << 363 ori r5, r0, MICROBLAZE_LMB_TLB_ID << 364 mts rtlbx,r5 << 365 nop << 366 mts rtlbhi,r0 << 367 nop << 368 addi r15, r0, machine_halt << 369 ori r17, r0, start_kernel << 370 ori r4, r0, MSR_KERNEL_VMS << 371 mts rmsr, r4 << 372 nop << 373 rted r17, 0 /* enable MMU << 374 nop <<
Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.