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/cpuconf.h>
38 #include <machine/pte-v6.h>
40 __FBSDID("$FreeBSD$");
44 #if defined(__ARM_ARCH_7VE__) || defined(__clang__)
46 * HYP support is in bintuils >= 2.21 and gcc >= 4.9 defines __ARM_ARCH_7VE__
47 * when enabled. llvm >= 3.6 supports it too.
50 #define MSR_ELR_HYP(regnum) msr elr_hyp, lr
53 #define MSR_ELR_HYP(regnum) .word (0xe12ef300 | regnum)
54 #define ERET .word 0xe160006e
56 #endif /* __ARM_ARCH >= 7 */
58 /* A small statically-allocated stack used only during initarm() and AP startup. */
59 #define INIT_ARM_STACK_SIZE 2048
66 /* Leave HYP mode */ ;\
68 and r0, r0, #(PSR_MODE) /* Mode is in the low 5 bits of CPSR */ ;\
69 teq r0, #(PSR_HYP32_MODE) /* Hyp Mode? */ ;\
71 /* Ensure that IRQ, FIQ and Aborts will be disabled after eret */ ;\
73 bic r0, r0, #(PSR_MODE) ;\
74 orr r0, r0, #(PSR_SVC32_MODE) ;\
75 orr r0, r0, #(PSR_I | PSR_F | PSR_A) ;\
77 /* Exit hypervisor mode */ ;\
84 #endif /* __ARM_ARCH >= 7 */
87 * On entry for FreeBSD boot ABI:
88 * r0 - metadata pointer or 0 (boothowto on AT91's boot2)
89 * r1 - if (r0 == 0) then metadata pointer
90 * On entry for Linux boot ABI:
92 * r1 - machine type (passed as arg2 to initarm)
93 * r2 - Pointer to a tagged list or dtb image (phys addr) (passed as arg1 initarm)
95 * For both types of boot we gather up the args, put them in a struct arm_boot_params
96 * structure and pass that to initarm.
101 STOP_UNWINDING /* Can't unwind into the bootloader! */
103 /* Make sure interrupts are disabled. */
106 mov r8, r0 /* 0 or boot mode from boot2 */
107 mov r9, r1 /* Save Machine type */
108 mov r10, r2 /* Save meta data */
109 mov r11, r3 /* Future expansion */
114 * Check whether data cache is enabled. If it is, then we know
115 * current tags are valid (not power-on garbage values) and there
116 * might be dirty lines that need cleaning. Disable cache to prevent
117 * new lines being allocated, then call wbinv_poc_all to clean it.
120 tst r7, #CPU_CONTROL_DC_ENABLE
121 blne dcache_wbinv_poc_all
123 /* ! Do not write to memory between wbinv and disabling cache ! */
126 * Now there are no dirty lines, but there may still be lines marked
127 * valid. Disable all caches and the MMU, and invalidate everything
128 * before setting up new page tables and re-enabling the mmu.
131 bic r7, #CPU_CONTROL_DC_ENABLE
132 bic r7, #CPU_CONTROL_AFLT_ENABLE
133 bic r7, #CPU_CONTROL_MMU_ENABLE
134 bic r7, #CPU_CONTROL_IC_ENABLE
135 bic r7, #CPU_CONTROL_BPRD_ENABLE
136 bic r7, #CPU_CONTROL_SW_ENABLE
137 orr r7, #CPU_CONTROL_UNAL_ENABLE
138 orr r7, #CPU_CONTROL_VECRELOC
142 bl dcache_inv_poc_all
148 * Build page table from scratch.
152 * Figure out the physical address we're loaded at by assuming this
153 * entry point code is in the first L1 section and so if we clear the
154 * offset bits of the pc that will give us the section-aligned load
155 * address, which remains in r5 throughout all the following code.
157 ldr r2, =(L1_S_OFFSET)
160 /* Find the delta between VA and PA, result stays in r0 throughout. */
162 bl translate_va_to_pa
165 * First map the entire 4GB address space as VA=PA. It's mapped as
166 * normal (cached) memory because it's for things like accessing the
167 * parameters passed in from the bootloader, which might be at any
168 * physical address, different for every platform.
176 * Next we do 64MiB starting at the physical load address, mapped to
177 * the VA the kernel is linked for.
180 ldr r2, =(KERNVIRTADDR)
184 /* Create a device mapping for early_printf if specified. */
185 #if defined(SOCDEV_PA) && defined(SOCDEV_VA)
189 bl build_device_pagetables
193 /* Transition the PC from physical to virtual addressing. */
197 /* Setup stack, clear BSS */
199 ldmia r1, {r1, r2, sp} /* Set initial stack and */
200 add sp, sp, #INIT_ARM_STACK_SIZE
201 sub r2, r2, r1 /* get zero init data */
204 str r3, [r1], #0x0004 /* get zero init data */
208 mov r1, #28 /* loader info size is 28 bytes also second arg */
209 subs sp, sp, r1 /* allocate arm_boot_params struct on stack */
210 mov r0, sp /* loader info pointer is first arg */
211 bic sp, sp, #7 /* align stack to 8 bytes */
212 str r1, [r0] /* Store length of loader info */
213 str r8, [r0, #4] /* Store r0 from boot loader */
214 str r9, [r0, #8] /* Store r1 from boot loader */
215 str r10, [r0, #12] /* store r2 from boot loader */
216 str r11, [r0, #16] /* store r3 from boot loader */
217 str r5, [r0, #20] /* store the physical address */
218 adr r4, Lpagetable /* load the pagetable address */
220 str r5, [r0, #24] /* store the pagetable address */
221 mov fp, #0 /* trace back starts here */
222 bl _C_LABEL(initarm) /* Off we go */
224 /* init arm will return the new stack pointer. */
227 bl _C_LABEL(mi_startup) /* call mi_startup()! */
229 ldr r0, =.Lmainreturned
234 #define VA_TO_PA_POINTER(name, table) \
240 * Returns the physical address of a magic va to pa pointer.
241 * r0 - The pagetable data pointer. This must be built using the
242 * VA_TO_PA_POINTER macro.
244 * VA_TO_PA_POINTER(Lpagetable, pagetable)
247 * bl translate_va_to_pa
248 * r0 will now contain the physical address of pagetable
254 /* At this point: r2 = VA - PA */
257 * Find the physical address of the table. After these two
261 * r0 = va(pagetable) - (VA - PA)
262 * = va(pagetable) - VA + PA
271 * r0 - the table base address
276 /* Setup TLB and MMU registers */
277 mcr CP15_TTBR0(r0) /* Set TTB */
279 mcr CP15_CONTEXTIDR(r0) /* Set ASID to 0 */
281 /* Set the Domain Access register */
282 mov r0, #DOMAIN_CLIENT /* Only domain #0 is used */
286 * Set TEX remap registers
287 * - All is set to uncacheable memory
293 mcr CP15_TLBIALL /* Flush TLB */
299 orr r0, r0, #CPU_CONTROL_MMU_ENABLE
300 orr r0, r0, #CPU_CONTROL_V6_EXTPAGE
301 orr r0, r0, #CPU_CONTROL_TR_ENABLE
302 orr r0, r0, #CPU_CONTROL_AF_ENABLE
306 mcr CP15_TLBIALL /* Flush TLB */
307 mcr CP15_BPIALL /* Flush Branch predictor */
316 * Init SMP coherent mode, enable caching and switch to final MMU table.
317 * Called with disabled caches
318 * r0 - The table base address
319 * r1 - clear bits for aux register
320 * r2 - set bits for aux register
322 ASENTRY_NP(reinit_mmu)
328 /* !! Be very paranoid here !! */
329 /* !! We cannot write single bit here !! */
331 #if 0 /* XXX writeback shouldn't be necessary */
332 /* Write back and invalidate all integrated caches */
333 bl dcache_wbinv_poc_all
335 bl dcache_inv_pou_all
341 /* Set auxiliary register */
343 bic r8, r7, r5 /* Mask bits */
344 eor r8, r8, r6 /* Set bits */
352 orr r7, #CPU_CONTROL_DC_ENABLE
353 orr r7, #CPU_CONTROL_IC_ENABLE
354 orr r7, #CPU_CONTROL_BPRD_ENABLE
358 mcr CP15_TTBR0(r4) /* Set new TTB */
362 mcr CP15_TLBIALL /* Flush TLB */
363 mcr CP15_BPIALL /* Flush Branch predictor */
367 #if 0 /* XXX writeback shouldn't be necessary */
368 /* Write back and invalidate all integrated caches */
369 bl dcache_wbinv_poc_all
371 bl dcache_inv_pou_all
382 * Builds the page table
383 * r0 - The table base address
384 * r1 - The physical address (trashed)
385 * r2 - The virtual address (trashed)
386 * r3 - The number of 1MiB sections
389 * Addresses must be 1MiB aligned
391 build_device_pagetables:
392 ldr r4, =PTE1_V|PTE1_A|PTE1_AP_KRW|TEX1_CLASS_0
395 /* Set the required page attributed */
396 ldr r4, =PTE1_V|PTE1_A|PTE1_AP_KRW|TEX1_CLASS_0
400 /* Move the virtual address to the correct bit location */
401 lsr r2, #(PTE1_SHIFT - 2)
407 add r1, r1, #(PTE1_SIZE)
413 VA_TO_PA_POINTER(Lpagetable, boot_pt1)
417 .word _edata /* Note that these three items are */
418 .word _ebss /* loaded with a single ldmia and */
419 .word svcstk /* must remain in order together. */
422 .asciz "main() returned"
427 .space INIT_ARM_STACK_SIZE * MAXCPU
430 * Memory for the initial pagetable. We are unable to place this in
431 * the bss as this will be cleared after the table is loaded.
433 .section ".init_pagetable"
434 .align 14 /* 16KiB aligned */
443 .word _C_LABEL(cpufuncs)
448 /* Make sure interrupts are disabled. */
453 /* Setup core, disable all caches. */
455 bic r0, #CPU_CONTROL_MMU_ENABLE
456 bic r0, #CPU_CONTROL_AFLT_ENABLE
457 bic r0, #CPU_CONTROL_DC_ENABLE
458 bic r0, #CPU_CONTROL_IC_ENABLE
459 bic r0, #CPU_CONTROL_BPRD_ENABLE
460 bic r0, #CPU_CONTROL_SW_ENABLE
461 orr r0, #CPU_CONTROL_UNAL_ENABLE
462 orr r0, #CPU_CONTROL_VECRELOC
467 /* Invalidate L1 cache I+D cache */
468 bl dcache_inv_pou_all
473 /* Find the delta between VA and PA */
475 bl translate_va_to_pa
479 adr r1, .Lstart+8 /* Get initstack pointer from */
480 ldr sp, [r1] /* startup data. */
481 mrc CP15_MPIDR(r0) /* Get processor id number. */
483 mov r1, #INIT_ARM_STACK_SIZE
484 mul r2, r1, r0 /* Point sp to initstack */
485 add sp, sp, r2 /* area for this processor. */
487 /* Switch to virtual addresses. */
490 mov fp, #0 /* trace back starts here */
491 bl _C_LABEL(init_secondary)/* Off we go, cpu id in r0. */
499 .asciz "init_secondary() returned"
505 /* XXX re-implement !!! */
507 bl dcache_wbinv_poc_all
509 ldr r4, .Lcpu_reset_address
518 * _cpu_reset_address contains the address to branch to, to complete
519 * the cpu reset after turning the MMU off
520 * This variable is provided by the hardware specific code
523 .word _C_LABEL(cpu_reset_address)
543 .global _C_LABEL(esym)
544 _C_LABEL(esym): .word _C_LABEL(end)
555 * Call the sigreturn system call.
557 * We have to load r7 manually rather than using
558 * "ldr r7, =SYS_sigreturn" to ensure the value of szsigcode is
559 * correct. Using the alternative places esigcode at the address
560 * of the data rather than the address one past the data.
563 ldr r7, [pc, #12] /* Load SYS_sigreturn */
566 /* Well if that failed we better exit quick ! */
568 ldr r7, [pc, #8] /* Load SYS_exit */
571 /* Branch back to retry SYS_sigreturn */
578 .global _C_LABEL(esigcode)
584 .long esigcode-sigcode
586 /* End of locore.S */