2 * Copyright 2004-2014 Olivier Houchard <cognet@FreeBSD.org>
3 * Copyright 2012-2014 Ian Lepore <ian@FreeBSD.org>
4 * Copyright 2013-2014 Andrew Turner <andrew@FreeBSD.org>
5 * Copyright 2014 Svatopluk Kraus <onwahe@gmail.com>
6 * Copyright 2014 Michal Meloun <meloun@miracle.cz>
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in the
16 * documentation and/or other materials provided with the distribution.
18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 #include <sys/syscall.h>
33 #include <machine/asm.h>
34 #include <machine/asmacros.h>
35 #include <machine/armreg.h>
36 #include <machine/sysreg.h>
37 #include <machine/pte-v6.h>
39 __FBSDID("$FreeBSD$");
43 #if defined(__ARM_ARCH_7VE__) || defined(__clang__)
45 * HYP support is in bintuils >= 2.21 and gcc >= 4.9 defines __ARM_ARCH_7VE__
46 * when enabled. llvm >= 3.6 supports it too.
49 #define MSR_ELR_HYP(regnum) msr elr_hyp, lr
52 #define MSR_ELR_HYP(regnum) .word (0xe12ef300 | regnum)
53 #define ERET .word 0xe160006e
55 #endif /* __ARM_ARCH >= 7 */
57 /* A small statically-allocated stack used only during initarm() and AP startup. */
58 #define INIT_ARM_STACK_SIZE 2048
65 /* Leave HYP mode */ ;\
67 and r0, r0, #(PSR_MODE) /* Mode is in the low 5 bits of CPSR */ ;\
68 teq r0, #(PSR_HYP32_MODE) /* Hyp Mode? */ ;\
70 /* Ensure that IRQ, FIQ and Aborts will be disabled after eret */ ;\
72 bic r0, r0, #(PSR_MODE) ;\
73 orr r0, r0, #(PSR_SVC32_MODE) ;\
74 orr r0, r0, #(PSR_I | PSR_F | PSR_A) ;\
76 /* Exit hypervisor mode */ ;\
83 #endif /* __ARM_ARCH >= 7 */
86 * On entry for FreeBSD boot ABI:
87 * r0 - metadata pointer or 0 (boothowto on AT91's boot2)
88 * r1 - if (r0 == 0) then metadata pointer
89 * On entry for Linux boot ABI:
91 * r1 - machine type (passed as arg2 to initarm)
92 * r2 - Pointer to a tagged list or dtb image (phys addr) (passed as arg1 initarm)
94 * For both types of boot we gather up the args, put them in a struct arm_boot_params
95 * structure and pass that to initarm.
100 STOP_UNWINDING /* Can't unwind into the bootloader! */
102 /* Make sure interrupts are disabled. */
105 mov r8, r0 /* 0 or boot mode from boot2 */
106 mov r9, r1 /* Save Machine type */
107 mov r10, r2 /* Save meta data */
108 mov r11, r3 /* Future expansion */
113 * Check whether data cache is enabled. If it is, then we know
114 * current tags are valid (not power-on garbage values) and there
115 * might be dirty lines that need cleaning. Disable cache to prevent
116 * new lines being allocated, then call wbinv_poc_all to clean it.
119 tst r7, #CPU_CONTROL_DC_ENABLE
120 blne dcache_wbinv_poc_all
122 /* ! Do not write to memory between wbinv and disabling cache ! */
125 * Now there are no dirty lines, but there may still be lines marked
126 * valid. Disable all caches and the MMU, and invalidate everything
127 * before setting up new page tables and re-enabling the mmu.
130 bic r7, #CPU_CONTROL_DC_ENABLE
131 bic r7, #CPU_CONTROL_AFLT_ENABLE
132 bic r7, #CPU_CONTROL_MMU_ENABLE
133 bic r7, #CPU_CONTROL_IC_ENABLE
134 bic r7, #CPU_CONTROL_BPRD_ENABLE
135 bic r7, #CPU_CONTROL_SW_ENABLE
136 orr r7, #CPU_CONTROL_UNAL_ENABLE
137 orr r7, #CPU_CONTROL_VECRELOC
141 bl dcache_inv_poc_all
147 * Build page table from scratch.
151 * Figure out the physical address we're loaded at by assuming this
152 * entry point code is in the first L1 section and so if we clear the
153 * offset bits of the pc that will give us the section-aligned load
154 * address, which remains in r5 throughout all the following code.
156 ldr r2, =(L1_S_OFFSET)
159 /* Find the delta between VA and PA, result stays in r0 throughout. */
161 bl translate_va_to_pa
164 * First map the entire 4GB address space as VA=PA. It's mapped as
165 * normal (cached) memory because it's for things like accessing the
166 * parameters passed in from the bootloader, which might be at any
167 * physical address, different for every platform.
175 * Next we do 64MiB starting at the physical load address, mapped to
176 * the VA the kernel is linked for.
179 ldr r2, =(KERNVIRTADDR)
183 /* Create a device mapping for early_printf if specified. */
184 #if defined(SOCDEV_PA) && defined(SOCDEV_VA)
188 bl build_device_pagetables
192 /* Transition the PC from physical to virtual addressing. */
196 /* Setup stack, clear BSS */
198 ldmia r1, {r1, r2, sp} /* Set initial stack and */
199 add sp, sp, #INIT_ARM_STACK_SIZE
200 sub r2, r2, r1 /* get zero init data */
203 str r3, [r1], #0x0004 /* get zero init data */
207 mov r1, #28 /* loader info size is 28 bytes also second arg */
208 subs sp, sp, r1 /* allocate arm_boot_params struct on stack */
209 mov r0, sp /* loader info pointer is first arg */
210 bic sp, sp, #7 /* align stack to 8 bytes */
211 str r1, [r0] /* Store length of loader info */
212 str r8, [r0, #4] /* Store r0 from boot loader */
213 str r9, [r0, #8] /* Store r1 from boot loader */
214 str r10, [r0, #12] /* store r2 from boot loader */
215 str r11, [r0, #16] /* store r3 from boot loader */
216 str r5, [r0, #20] /* store the physical address */
217 adr r4, Lpagetable /* load the pagetable address */
219 str r5, [r0, #24] /* store the pagetable address */
220 mov fp, #0 /* trace back starts here */
221 bl _C_LABEL(initarm) /* Off we go */
223 /* init arm will return the new stack pointer. */
226 bl _C_LABEL(mi_startup) /* call mi_startup()! */
228 ldr r0, =.Lmainreturned
233 #define VA_TO_PA_POINTER(name, table) \
239 * Returns the physical address of a magic va to pa pointer.
240 * r0 - The pagetable data pointer. This must be built using the
241 * VA_TO_PA_POINTER macro.
243 * VA_TO_PA_POINTER(Lpagetable, pagetable)
246 * bl translate_va_to_pa
247 * r0 will now contain the physical address of pagetable
253 /* At this point: r2 = VA - PA */
256 * Find the physical address of the table. After these two
260 * r0 = va(pagetable) - (VA - PA)
261 * = va(pagetable) - VA + PA
270 * r0 - the table base address
275 /* Setup TLB and MMU registers */
276 mcr CP15_TTBR0(r0) /* Set TTB */
278 mcr CP15_CONTEXTIDR(r0) /* Set ASID to 0 */
280 /* Set the Domain Access register */
281 mov r0, #DOMAIN_CLIENT /* Only domain #0 is used */
285 * Set TEX remap registers
286 * - All is set to uncacheable memory
292 mcr CP15_TLBIALL /* Flush TLB */
298 orr r0, r0, #CPU_CONTROL_MMU_ENABLE
299 orr r0, r0, #CPU_CONTROL_V6_EXTPAGE
300 orr r0, r0, #CPU_CONTROL_TR_ENABLE
301 orr r0, r0, #CPU_CONTROL_AF_ENABLE
305 mcr CP15_TLBIALL /* Flush TLB */
306 mcr CP15_BPIALL /* Flush Branch predictor */
315 * Init SMP coherent mode, enable caching and switch to final MMU table.
316 * Called with disabled caches
317 * r0 - The table base address
318 * r1 - clear bits for aux register
319 * r2 - set bits for aux register
321 ASENTRY_NP(reinit_mmu)
327 /* !! Be very paranoid here !! */
328 /* !! We cannot write single bit here !! */
330 #if 0 /* XXX writeback shouldn't be necessary */
331 /* Write back and invalidate all integrated caches */
332 bl dcache_wbinv_poc_all
334 bl dcache_inv_pou_all
340 /* Set auxiliary register */
342 bic r8, r7, r5 /* Mask bits */
343 eor r8, r8, r6 /* Set bits */
351 orr r7, #CPU_CONTROL_DC_ENABLE
352 orr r7, #CPU_CONTROL_IC_ENABLE
353 orr r7, #CPU_CONTROL_BPRD_ENABLE
357 mcr CP15_TTBR0(r4) /* Set new TTB */
361 mcr CP15_TLBIALL /* Flush TLB */
362 mcr CP15_BPIALL /* Flush Branch predictor */
366 #if 0 /* XXX writeback shouldn't be necessary */
367 /* Write back and invalidate all integrated caches */
368 bl dcache_wbinv_poc_all
370 bl dcache_inv_pou_all
381 * Builds the page table
382 * r0 - The table base address
383 * r1 - The physical address (trashed)
384 * r2 - The virtual address (trashed)
385 * r3 - The number of 1MiB sections
388 * Addresses must be 1MiB aligned
390 build_device_pagetables:
391 ldr r4, =PTE1_V|PTE1_A|PTE1_AP_KRW|TEX1_CLASS_0
394 /* Set the required page attributed */
395 ldr r4, =PTE1_V|PTE1_A|PTE1_AP_KRW|TEX1_CLASS_0
399 /* Move the virtual address to the correct bit location */
400 lsr r2, #(PTE1_SHIFT - 2)
406 add r1, r1, #(PTE1_SIZE)
412 VA_TO_PA_POINTER(Lpagetable, boot_pt1)
416 .word _edata /* Note that these three items are */
417 .word _ebss /* loaded with a single ldmia and */
418 .word svcstk /* must remain in order together. */
421 .asciz "main() returned"
426 .space INIT_ARM_STACK_SIZE * MAXCPU
429 * Memory for the initial pagetable. We are unable to place this in
430 * the bss as this will be cleared after the table is loaded.
432 .section ".init_pagetable"
433 .align 14 /* 16KiB aligned */
444 /* Make sure interrupts are disabled. */
449 /* Setup core, disable all caches. */
451 bic r0, #CPU_CONTROL_MMU_ENABLE
452 bic r0, #CPU_CONTROL_AFLT_ENABLE
453 bic r0, #CPU_CONTROL_DC_ENABLE
454 bic r0, #CPU_CONTROL_IC_ENABLE
455 bic r0, #CPU_CONTROL_BPRD_ENABLE
456 bic r0, #CPU_CONTROL_SW_ENABLE
457 orr r0, #CPU_CONTROL_UNAL_ENABLE
458 orr r0, #CPU_CONTROL_VECRELOC
463 /* Invalidate L1 cache I+D cache */
464 bl dcache_inv_pou_all
469 /* Find the delta between VA and PA */
471 bl translate_va_to_pa
475 adr r1, .Lstart+8 /* Get initstack pointer from */
476 ldr sp, [r1] /* startup data. */
477 mrc CP15_MPIDR(r0) /* Get processor id number. */
479 mov r1, #INIT_ARM_STACK_SIZE
480 mul r2, r1, r0 /* Point sp to initstack */
481 add sp, sp, r2 /* area for this processor. */
483 /* Switch to virtual addresses. */
486 mov fp, #0 /* trace back starts here */
487 bl _C_LABEL(init_secondary)/* Off we go, cpu id in r0. */
495 .asciz "init_secondary() returned"
501 /* XXX re-implement !!! */
503 bl dcache_wbinv_poc_all
505 ldr r4, .Lcpu_reset_address
514 * _cpu_reset_address contains the address to branch to, to complete
515 * the cpu reset after turning the MMU off
516 * This variable is provided by the hardware specific code
519 .word _C_LABEL(cpu_reset_address)
539 .global _C_LABEL(esym)
540 _C_LABEL(esym): .word _C_LABEL(end)
551 * Call the sigreturn system call.
553 * We have to load r7 manually rather than using
554 * "ldr r7, =SYS_sigreturn" to ensure the value of szsigcode is
555 * correct. Using the alternative places esigcode at the address
556 * of the data rather than the address one past the data.
559 ldr r7, [pc, #12] /* Load SYS_sigreturn */
562 /* Well if that failed we better exit quick ! */
564 ldr r7, [pc, #8] /* Load SYS_exit */
567 /* Branch back to retry SYS_sigreturn */
574 .global _C_LABEL(esigcode)
580 .long esigcode-sigcode
582 /* End of locore.S */