/*- * Copyright (c) 2012-2014 Andrew Turner * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * $FreeBSD$ */ #include "assym.inc" #include "opt_kstack_pages.h" #include #include #include #include #include #include #include #include #define VIRT_BITS 48 #define DMAP_TABLES ((DMAP_MAX_ADDRESS - DMAP_MIN_ADDRESS) >> L0_SHIFT) .globl kernbase .set kernbase, KERNBASE /* * We assume: * MMU on with an identity map, or off * D-Cache: off * I-Cache: on or off * We are loaded at a 2MiB aligned address */ ENTRY(_start) /* Drop to EL1 */ bl drop_to_el1 /* * Disable the MMU. We may have entered the kernel with it on and * will need to update the tables later. If this has been set up * with anything other than a VA == PA map then this will fail, * but in this case the code to find where we are running from * would have also failed. */ dsb sy mrs x2, sctlr_el1 bic x2, x2, SCTLR_M msr sctlr_el1, x2 isb /* Set the context id */ msr contextidr_el1, xzr /* Get the virt -> phys offset */ bl get_virt_delta /* * At this point: * x29 = PA - VA * x28 = Our physical load address */ /* Create the page tables */ bl create_pagetables /* * At this point: * x27 = TTBR0 table * x26 = Kernel L1 table * x24 = TTBR1 table */ /* Enable the mmu */ bl start_mmu /* Load the new ttbr0 pagetable */ adrp x27, pagetable_l0_ttbr0 add x27, x27, :lo12:pagetable_l0_ttbr0 /* Jump to the virtual address space */ ldr x15, .Lvirtdone br x15 virtdone: /* Set up the stack */ adrp x25, initstack_end add x25, x25, :lo12:initstack_end mov sp, x25 sub sp, sp, #PCB_SIZE /* Zero the BSS */ ldr x15, .Lbss ldr x14, .Lend 1: str xzr, [x15], #8 cmp x15, x14 b.lo 1b #if defined(PERTHREAD_SSP) /* Set sp_el0 to the boot canary for early per-thread SSP to work */ adrp x15, boot_canary add x15, x15, :lo12:boot_canary msr sp_el0, x15 #endif /* Backup the module pointer */ mov x1, x0 /* Make the page table base a virtual address */ sub x26, x26, x29 sub x24, x24, x29 sub sp, sp, #BOOTPARAMS_SIZE mov x0, sp /* Degate the delda so it is VA -> PA */ neg x29, x29 str x1, [x0, #BP_MODULEP] str x26, [x0, #BP_KERN_L1PT] str x29, [x0, #BP_KERN_DELTA] adrp x25, initstack add x25, x25, :lo12:initstack str x25, [x0, #BP_KERN_STACK] str x24, [x0, #BP_KERN_L0PT] str x27, [x0, #BP_KERN_TTBR0] str x23, [x0, #BP_BOOT_EL] /* trace back starts here */ mov fp, #0 /* Branch to C code */ bl initarm /* We are done with the boot params */ add sp, sp, #BOOTPARAMS_SIZE /* * Enable pointer authentication in the kernel. We set the keys for * thread0 in initarm so have to wait until it returns to enable it. * If we were to enable it in initarm then any authentication when * returning would fail as it was called with pointer authentication * disabled. */ bl ptrauth_start bl mi_startup /* We should not get here */ brk 0 .align 3 .Lvirtdone: .quad virtdone .Lbss: .quad __bss_start .Lend: .quad __bss_end END(_start) #ifdef SMP /* * mpentry(unsigned long) * * Called by a core when it is being brought online. * The data in x0 is passed straight to init_secondary. */ ENTRY(mpentry) /* Disable interrupts */ msr daifset, #DAIF_INTR /* Drop to EL1 */ bl drop_to_el1 /* Set the context id */ msr contextidr_el1, xzr /* Load the kernel page table */ adrp x24, pagetable_l0_ttbr1 add x24, x24, :lo12:pagetable_l0_ttbr1 /* Load the identity page table */ adrp x27, pagetable_l0_ttbr0_boostrap add x27, x27, :lo12:pagetable_l0_ttbr0_boostrap /* Enable the mmu */ bl start_mmu /* Load the new ttbr0 pagetable */ adrp x27, pagetable_l0_ttbr0 add x27, x27, :lo12:pagetable_l0_ttbr0 /* Jump to the virtual address space */ ldr x15, =mp_virtdone br x15 mp_virtdone: /* Start using the AP boot stack */ ldr x4, =bootstack ldr x4, [x4] mov sp, x4 #if defined(PERTHREAD_SSP) /* Set sp_el0 to the boot canary for early per-thread SSP to work */ adrp x15, boot_canary add x15, x15, :lo12:boot_canary msr sp_el0, x15 #endif /* Load the kernel ttbr0 pagetable */ msr ttbr0_el1, x27 isb /* Invalidate the TLB */ tlbi vmalle1 dsb sy isb b init_secondary END(mpentry) #endif /* * If we are started in EL2, configure the required hypervisor * registers and drop to EL1. */ LENTRY(drop_to_el1) mrs x23, CurrentEL lsr x23, x23, #2 cmp x23, #0x2 b.eq 1f ret 1: /* Configure the Hypervisor */ ldr x2, =(HCR_RW | HCR_APK | HCR_API) msr hcr_el2, x2 /* Load the Virtualization Process ID Register */ mrs x2, midr_el1 msr vpidr_el2, x2 /* Load the Virtualization Multiprocess ID Register */ mrs x2, mpidr_el1 msr vmpidr_el2, x2 /* Set the bits that need to be 1 in sctlr_el1 */ ldr x2, .Lsctlr_res1 msr sctlr_el1, x2 /* Don't trap to EL2 for exceptions */ mov x2, #CPTR_RES1 msr cptr_el2, x2 /* Don't trap to EL2 for CP15 traps */ msr hstr_el2, xzr /* Enable access to the physical timers at EL1 */ mrs x2, cnthctl_el2 orr x2, x2, #(CNTHCTL_EL1PCTEN | CNTHCTL_EL1PCEN) msr cnthctl_el2, x2 /* Set the counter offset to a known value */ msr cntvoff_el2, xzr /* Hypervisor trap functions */ adrp x2, hyp_vectors add x2, x2, :lo12:hyp_vectors msr vbar_el2, x2 mov x2, #(PSR_F | PSR_I | PSR_A | PSR_D | PSR_M_EL1h) msr spsr_el2, x2 /* Configure GICv3 CPU interface */ mrs x2, id_aa64pfr0_el1 /* Extract GIC bits from the register */ ubfx x2, x2, #ID_AA64PFR0_GIC_SHIFT, #ID_AA64PFR0_GIC_BITS /* GIC[3:0] == 0001 - GIC CPU interface via special regs. supported */ cmp x2, #(ID_AA64PFR0_GIC_CPUIF_EN >> ID_AA64PFR0_GIC_SHIFT) b.ne 2f mrs x2, icc_sre_el2 orr x2, x2, #ICC_SRE_EL2_EN /* Enable access from insecure EL1 */ orr x2, x2, #ICC_SRE_EL2_SRE /* Enable system registers */ msr icc_sre_el2, x2 2: /* Set the address to return to our return address */ msr elr_el2, x30 isb eret .align 3 .Lsctlr_res1: .quad SCTLR_RES1 LEND(drop_to_el1) #define VECT_EMPTY \ .align 7; \ 1: b 1b .align 11 hyp_vectors: VECT_EMPTY /* Synchronous EL2t */ VECT_EMPTY /* IRQ EL2t */ VECT_EMPTY /* FIQ EL2t */ VECT_EMPTY /* Error EL2t */ VECT_EMPTY /* Synchronous EL2h */ VECT_EMPTY /* IRQ EL2h */ VECT_EMPTY /* FIQ EL2h */ VECT_EMPTY /* Error EL2h */ VECT_EMPTY /* Synchronous 64-bit EL1 */ VECT_EMPTY /* IRQ 64-bit EL1 */ VECT_EMPTY /* FIQ 64-bit EL1 */ VECT_EMPTY /* Error 64-bit EL1 */ VECT_EMPTY /* Synchronous 32-bit EL1 */ VECT_EMPTY /* IRQ 32-bit EL1 */ VECT_EMPTY /* FIQ 32-bit EL1 */ VECT_EMPTY /* Error 32-bit EL1 */ /* * Get the delta between the physical address we were loaded to and the * virtual address we expect to run from. This is used when building the * initial page table. */ LENTRY(get_virt_delta) /* Load the physical address of virt_map */ adrp x29, virt_map add x29, x29, :lo12:virt_map /* Load the virtual address of virt_map stored in virt_map */ ldr x28, [x29] /* Find PA - VA as PA' = VA' - VA + PA = VA' + (PA - VA) = VA' + x29 */ sub x29, x29, x28 /* Find the load address for the kernel */ mov x28, #(KERNBASE) add x28, x28, x29 ret .align 3 virt_map: .quad virt_map LEND(get_virt_delta) /* * This builds the page tables containing the identity map, and the kernel * virtual map. * * It relys on: * We were loaded to an address that is on a 2MiB boundary * All the memory must not cross a 1GiB boundaty * x28 contains the physical address we were loaded from * * TODO: This is out of date. * There are at least 5 pages before that address for the page tables * The pages used are: * - The Kernel L2 table * - The Kernel L1 table * - The Kernel L0 table (TTBR1) * - The identity (PA = VA) L1 table * - The identity (PA = VA) L0 table (TTBR0) * - The DMAP L1 tables */ LENTRY(create_pagetables) /* Save the Link register */ mov x5, x30 /* Clean the page table */ adrp x6, pagetable add x6, x6, :lo12:pagetable mov x26, x6 adrp x27, pagetable_end add x27, x27, :lo12:pagetable_end 1: stp xzr, xzr, [x6], #16 stp xzr, xzr, [x6], #16 stp xzr, xzr, [x6], #16 stp xzr, xzr, [x6], #16 cmp x6, x27 b.lo 1b /* * Build the TTBR1 maps. */ /* Find the size of the kernel */ mov x6, #(KERNBASE) #if defined(LINUX_BOOT_ABI) /* X19 is used as 'map FDT data' flag */ mov x19, xzr /* No modules or FDT pointer ? */ cbz x0, booti_no_fdt /* * Test if x0 points to modules descriptor(virtual address) or * to FDT (physical address) */ cmp x0, x6 /* x6 is #(KERNBASE) */ b.lo booti_fdt #endif /* Booted with modules pointer */ /* Find modulep - begin */ sub x8, x0, x6 /* Add two 2MiB pages for the module data and round up */ ldr x7, =(3 * L2_SIZE - 1) add x8, x8, x7 b common #if defined(LINUX_BOOT_ABI) booti_fdt: /* Booted by U-Boot booti with FDT data */ /* Set 'map FDT data' flag */ mov x19, #1 booti_no_fdt: /* Booted by U-Boot booti without FTD data */ /* Find the end - begin */ ldr x7, .Lend sub x8, x7, x6 /* * Add one 2MiB page for copy of FDT data (maximum FDT size), * one for metadata and round up */ ldr x7, =(3 * L2_SIZE - 1) add x8, x8, x7 #endif common: /* Get the number of l2 pages to allocate, rounded down */ lsr x10, x8, #(L2_SHIFT) /* Create the kernel space L2 table */ mov x6, x26 mov x7, #(ATTR_S1_IDX(VM_MEMATTR_WRITE_BACK)) mov x8, #(KERNBASE & L2_BLOCK_MASK) mov x9, x28 bl build_l2_block_pagetable /* Move to the l1 table */ add x26, x26, #PAGE_SIZE /* Link the l1 -> l2 table */ mov x9, x6 mov x6, x26 bl link_l1_pagetable /* Move to the l0 table */ add x24, x26, #PAGE_SIZE /* Link the l0 -> l1 table */ mov x9, x6 mov x6, x24 mov x10, #1 bl link_l0_pagetable /* Link the DMAP tables */ ldr x8, =DMAP_MIN_ADDRESS adrp x9, pagetable_dmap add x9, x9, :lo12:pagetable_dmap mov x10, #DMAP_TABLES bl link_l0_pagetable /* * Build the TTBR0 maps. As TTBR0 maps, they must specify ATTR_S1_nG. * They are only needed early on, so the VA = PA map is uncached. */ add x27, x24, #PAGE_SIZE mov x6, x27 /* The initial page table */ /* Create the VA = PA map */ mov x7, #(ATTR_S1_nG | ATTR_S1_IDX(VM_MEMATTR_WRITE_BACK)) adrp x16, _start and x16, x16, #(~L2_OFFSET) mov x9, x16 /* PA start */ mov x8, x16 /* VA start (== PA start) */ mov x10, #1 bl build_l2_block_pagetable #if defined(SOCDEV_PA) /* Create a table for the UART */ mov x7, #(ATTR_S1_nG | ATTR_S1_IDX(VM_MEMATTR_DEVICE)) add x16, x16, #(L2_SIZE) /* VA start */ mov x8, x16 /* Store the socdev virtual address */ add x17, x8, #(SOCDEV_PA & L2_OFFSET) adrp x9, socdev_va str x17, [x9, :lo12:socdev_va] mov x9, #(SOCDEV_PA & ~L2_OFFSET) /* PA start */ mov x10, #1 bl build_l2_block_pagetable #endif #if defined(LINUX_BOOT_ABI) /* Map FDT data ? */ cbz x19, 1f /* Create the mapping for FDT data (2 MiB max) */ mov x7, #(ATTR_S1_nG | ATTR_S1_IDX(VM_MEMATTR_WRITE_BACK)) add x16, x16, #(L2_SIZE) /* VA start */ mov x8, x16 mov x9, x0 /* PA start */ /* Update the module pointer to point at the allocated memory */ and x0, x0, #(L2_OFFSET) /* Keep the lower bits */ add x0, x0, x8 /* Add the aligned virtual address */ mov x10, #1 bl build_l2_block_pagetable 1: #endif /* Move to the l1 table */ add x27, x27, #PAGE_SIZE /* Link the l1 -> l2 table */ mov x9, x6 mov x6, x27 bl link_l1_pagetable /* Move to the l0 table */ add x27, x27, #PAGE_SIZE /* Link the l0 -> l1 table */ mov x9, x6 mov x6, x27 mov x10, #1 bl link_l0_pagetable /* Restore the Link register */ mov x30, x5 ret LEND(create_pagetables) /* * Builds an L0 -> L1 table descriptor * * x6 = L0 table * x8 = Virtual Address * x9 = L1 PA (trashed) * x10 = Entry count (trashed) * x11, x12 and x13 are trashed */ LENTRY(link_l0_pagetable) /* * Link an L0 -> L1 table entry. */ /* Find the table index */ lsr x11, x8, #L0_SHIFT and x11, x11, #L0_ADDR_MASK /* Build the L0 block entry */ mov x12, #L0_TABLE orr x12, x12, #(TATTR_UXN_TABLE | TATTR_AP_TABLE_NO_EL0) /* Only use the output address bits */ lsr x9, x9, #PAGE_SHIFT 1: orr x13, x12, x9, lsl #PAGE_SHIFT /* Store the entry */ str x13, [x6, x11, lsl #3] sub x10, x10, #1 add x11, x11, #1 add x9, x9, #1 cbnz x10, 1b ret LEND(link_l0_pagetable) /* * Builds an L1 -> L2 table descriptor * * x6 = L1 table * x8 = Virtual Address * x9 = L2 PA (trashed) * x11, x12 and x13 are trashed */ LENTRY(link_l1_pagetable) /* * Link an L1 -> L2 table entry. */ /* Find the table index */ lsr x11, x8, #L1_SHIFT and x11, x11, #Ln_ADDR_MASK /* Build the L1 block entry */ mov x12, #L1_TABLE /* Only use the output address bits */ lsr x9, x9, #PAGE_SHIFT orr x13, x12, x9, lsl #PAGE_SHIFT /* Store the entry */ str x13, [x6, x11, lsl #3] ret LEND(link_l1_pagetable) /* * Builds count 2 MiB page table entry * x6 = L2 table * x7 = Block attributes * x8 = VA start * x9 = PA start (trashed) * x10 = Entry count (trashed) * x11, x12 and x13 are trashed */ LENTRY(build_l2_block_pagetable) /* * Build the L2 table entry. */ /* Find the table index */ lsr x11, x8, #L2_SHIFT and x11, x11, #Ln_ADDR_MASK /* Build the L2 block entry */ orr x12, x7, #L2_BLOCK orr x12, x12, #(ATTR_DEFAULT) orr x12, x12, #(ATTR_S1_UXN) /* Only use the output address bits */ lsr x9, x9, #L2_SHIFT /* Set the physical address for this virtual address */ 1: orr x13, x12, x9, lsl #L2_SHIFT /* Store the entry */ str x13, [x6, x11, lsl #3] sub x10, x10, #1 add x11, x11, #1 add x9, x9, #1 cbnz x10, 1b ret LEND(build_l2_block_pagetable) LENTRY(start_mmu) dsb sy /* Load the exception vectors */ ldr x2, =exception_vectors msr vbar_el1, x2 /* Load ttbr0 and ttbr1 */ msr ttbr0_el1, x27 msr ttbr1_el1, x24 isb /* Clear the Monitor Debug System control register */ msr mdscr_el1, xzr /* Invalidate the TLB */ tlbi vmalle1is dsb ish isb ldr x2, mair msr mair_el1, x2 /* * Setup TCR according to the PARange and ASIDBits fields * from ID_AA64MMFR0_EL1 and the HAFDBS field from the * ID_AA64MMFR1_EL1. More precisely, set TCR_EL1.AS * to 1 only if the ASIDBits field equals 0b0010. */ ldr x2, tcr mrs x3, id_aa64mmfr0_el1 /* Copy the bottom 3 bits from id_aa64mmfr0_el1 into TCR.IPS */ bfi x2, x3, #(TCR_IPS_SHIFT), #(TCR_IPS_WIDTH) and x3, x3, #(ID_AA64MMFR0_ASIDBits_MASK) /* Check if the HW supports 16 bit ASIDS */ cmp x3, #(ID_AA64MMFR0_ASIDBits_16) /* If so x3 == 1, else x3 == 0 */ cset x3, eq /* Set TCR.AS with x3 */ bfi x2, x3, #(TCR_ASID_SHIFT), #(TCR_ASID_WIDTH) /* * Check if the HW supports access flag and dirty state updates, * and set TCR_EL1.HA and TCR_EL1.HD accordingly. */ mrs x3, id_aa64mmfr1_el1 and x3, x3, #(ID_AA64MMFR1_HAFDBS_MASK) cmp x3, #1 b.ne 1f orr x2, x2, #(TCR_HA) b 2f 1: cmp x3, #2 b.ne 2f orr x2, x2, #(TCR_HA | TCR_HD) 2: msr tcr_el1, x2 /* * Setup SCTLR. */ ldr x2, sctlr_set ldr x3, sctlr_clear mrs x1, sctlr_el1 bic x1, x1, x3 /* Clear the required bits */ orr x1, x1, x2 /* Set the required bits */ msr sctlr_el1, x1 isb ret .align 3 mair: .quad MAIR_ATTR(MAIR_DEVICE_nGnRnE, VM_MEMATTR_DEVICE_nGnRnE) | \ MAIR_ATTR(MAIR_NORMAL_NC, VM_MEMATTR_UNCACHEABLE) | \ MAIR_ATTR(MAIR_NORMAL_WB, VM_MEMATTR_WRITE_BACK) | \ MAIR_ATTR(MAIR_NORMAL_WT, VM_MEMATTR_WRITE_THROUGH) | \ MAIR_ATTR(MAIR_DEVICE_nGnRE, VM_MEMATTR_DEVICE_nGnRE) tcr: .quad (TCR_TxSZ(64 - VIRT_BITS) | TCR_TG1_4K | \ TCR_CACHE_ATTRS | TCR_SMP_ATTRS) sctlr_set: /* Bits to set */ .quad (SCTLR_LSMAOE | SCTLR_nTLSMD | SCTLR_UCI | SCTLR_SPAN | \ SCTLR_nTWE | SCTLR_nTWI | SCTLR_UCT | SCTLR_DZE | \ SCTLR_I | SCTLR_SED | SCTLR_SA0 | SCTLR_SA | SCTLR_C | \ SCTLR_M | SCTLR_CP15BEN) sctlr_clear: /* Bits to clear */ .quad (SCTLR_EE | SCTLR_E0E | SCTLR_IESB | SCTLR_WXN | SCTLR_UMA | \ SCTLR_ITD | SCTLR_A) LEND(start_mmu) ENTRY(abort) b abort END(abort) .section .init_pagetable, "aw", %nobits .align PAGE_SHIFT /* * 6 initial tables (in the following order): * L2 for kernel (High addresses) * L1 for kernel * L0 for kernel * L1 bootstrap for user (Low addresses) * L0 bootstrap for user * L0 for user */ pagetable: .space PAGE_SIZE pagetable_l1_ttbr1: .space PAGE_SIZE pagetable_l0_ttbr1: .space PAGE_SIZE pagetable_l2_ttbr0_bootstrap: .space PAGE_SIZE pagetable_l1_ttbr0_bootstrap: .space PAGE_SIZE pagetable_l0_ttbr0_boostrap: .space PAGE_SIZE pagetable_l0_ttbr0: .space PAGE_SIZE .globl pagetable_dmap pagetable_dmap: .space PAGE_SIZE * DMAP_TABLES pagetable_end: el2_pagetable: .space PAGE_SIZE .align 4 initstack: .space (PAGE_SIZE * KSTACK_PAGES) initstack_end: .text EENTRY(aarch32_sigcode) .word 0xe1a0000d // mov r0, sp .word 0xe2800040 // add r0, r0, #SIGF_UC .word 0xe59f700c // ldr r7, [pc, #12] .word 0xef000000 // swi #0 .word 0xe59f7008 // ldr r7, [pc, #8] .word 0xef000000 // swi #0 .word 0xeafffffa // b . - 16 EEND(aarch32_sigcode) .word SYS_sigreturn .word SYS_exit .align 3 aarch32_esigcode: .data .global sz_aarch32_sigcode sz_aarch32_sigcode: .quad aarch32_esigcode - aarch32_sigcode