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authorAngelos Mouzakitis <a.mouzakitis@virtualopensystems.com>2023-10-10 14:33:42 +0000
committerAngelos Mouzakitis <a.mouzakitis@virtualopensystems.com>2023-10-10 14:33:42 +0000
commitaf1a266670d040d2f4083ff309d732d648afba2a (patch)
tree2fc46203448ddcc6f81546d379abfaeb323575e9 /roms/u-boot/arch/arm/cpu/armv8/exceptions.S
parente02cda008591317b1625707ff8e115a4841aa889 (diff)
Add submodule dependency filesHEADmaster
Change-Id: Iaf8d18082d3991dec7c0ebbea540f092188eb4ec
Diffstat (limited to 'roms/u-boot/arch/arm/cpu/armv8/exceptions.S')
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+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * (C) Copyright 2013
+ * David Feng <fenghua@phytium.com.cn>
+ */
+
+#include <asm-offsets.h>
+#include <config.h>
+#include <asm/ptrace.h>
+#include <asm/macro.h>
+#include <linux/linkage.h>
+
+/*
+ * AArch64 exception vectors:
+ * We have four types of exceptions:
+ * - synchronous: traps, data aborts, undefined instructions, ...
+ * - IRQ: group 1 (normal) interrupts
+ * - FIQ: group 0 or secure interrupts
+ * - SError: fatal system errors
+ * There are entries for all four of those for different contexts:
+ * - from same exception level, when using the SP_EL0 stack pointer
+ * - from same exception level, when using the SP_ELx stack pointer
+ * - from lower exception level, when this is AArch64
+ * - from lower exception level, when this is AArch32
+ * Each of those 16 entries have space for 32 instructions, each entry must
+ * be 128 byte aligned, the whole table must be 2K aligned.
+ * The 32 instructions are not enough to save and restore all registers and
+ * to branch to the actual handler, so we split this up:
+ * Each entry saves the LR, branches to the save routine, then to the actual
+ * handler, then to the restore routine. The save and restore routines are
+ * each split in half and stuffed in the unused gap between the entries.
+ * Also as we do not run anything in a lower exception level, we just provide
+ * the first 8 entries for exceptions from the same EL.
+ */
+ .align 11
+ .globl vectors
+vectors:
+ .align 7 /* Current EL Synchronous Thread */
+ stp x29, x30, [sp, #-16]!
+ bl _exception_entry
+ bl do_bad_sync
+ b exception_exit
+
+/*
+ * Save (most of) the GP registers to the stack frame.
+ * This is the first part of the shared routine called into from all entries.
+ */
+_exception_entry:
+ stp x27, x28, [sp, #-16]!
+ stp x25, x26, [sp, #-16]!
+ stp x23, x24, [sp, #-16]!
+ stp x21, x22, [sp, #-16]!
+ stp x19, x20, [sp, #-16]!
+ stp x17, x18, [sp, #-16]!
+ stp x15, x16, [sp, #-16]!
+ stp x13, x14, [sp, #-16]!
+ stp x11, x12, [sp, #-16]!
+ stp x9, x10, [sp, #-16]!
+ stp x7, x8, [sp, #-16]!
+ stp x5, x6, [sp, #-16]!
+ stp x3, x4, [sp, #-16]!
+ stp x1, x2, [sp, #-16]!
+ b _save_el_regs /* jump to the second part */
+
+ .align 7 /* Current EL IRQ Thread */
+ stp x29, x30, [sp, #-16]!
+ bl _exception_entry
+ bl do_bad_irq
+ b exception_exit
+
+/*
+ * Save exception specific context: ESR and ELR, for all exception levels.
+ * This is the second part of the shared routine called into from all entries.
+ */
+_save_el_regs:
+ /* Could be running at EL3/EL2/EL1 */
+ switch_el x11, 3f, 2f, 1f
+3: mrs x1, esr_el3
+ mrs x2, elr_el3
+ b 0f
+2: mrs x1, esr_el2
+ mrs x2, elr_el2
+ b 0f
+1: mrs x1, esr_el1
+ mrs x2, elr_el1
+0:
+ stp x2, x0, [sp, #-16]!
+ mov x0, sp
+ ret
+
+ .align 7 /* Current EL FIQ Thread */
+ stp x29, x30, [sp, #-16]!
+ bl _exception_entry
+ bl do_bad_fiq
+ /* falling through to _exception_exit */
+/*
+ * Restore the exception return address, for all exception levels.
+ * This is the first part of the shared routine called into from all entries.
+ */
+exception_exit:
+ ldp x2, x0, [sp],#16
+ switch_el x11, 3f, 2f, 1f
+3: msr elr_el3, x2
+ b _restore_regs
+2: msr elr_el2, x2
+ b _restore_regs
+1: msr elr_el1, x2
+ b _restore_regs /* jump to the second part */
+
+ .align 7 /* Current EL Error Thread */
+ stp x29, x30, [sp, #-16]!
+ bl _exception_entry
+ bl do_bad_error
+ b exception_exit
+
+/*
+ * Restore the general purpose registers from the exception stack, then return.
+ * This is the second part of the shared routine called into from all entries.
+ */
+_restore_regs:
+ ldp x1, x2, [sp],#16
+ ldp x3, x4, [sp],#16
+ ldp x5, x6, [sp],#16
+ ldp x7, x8, [sp],#16
+ ldp x9, x10, [sp],#16
+ ldp x11, x12, [sp],#16
+ ldp x13, x14, [sp],#16
+ ldp x15, x16, [sp],#16
+ ldp x17, x18, [sp],#16
+ ldp x19, x20, [sp],#16
+ ldp x21, x22, [sp],#16
+ ldp x23, x24, [sp],#16
+ ldp x25, x26, [sp],#16
+ ldp x27, x28, [sp],#16
+ ldp x29, x30, [sp],#16
+ eret
+
+ .align 7 /* Current EL (SP_ELx) Synchronous Handler */
+ stp x29, x30, [sp, #-16]!
+ bl _exception_entry
+ bl do_sync
+ b exception_exit
+
+ .align 7 /* Current EL (SP_ELx) IRQ Handler */
+ stp x29, x30, [sp, #-16]!
+ bl _exception_entry
+ bl do_irq
+ b exception_exit
+
+ .align 7 /* Current EL (SP_ELx) FIQ Handler */
+ stp x29, x30, [sp, #-16]!
+ bl _exception_entry
+ bl do_fiq
+ b exception_exit
+
+ .align 7 /* Current EL (SP_ELx) Error Handler */
+ stp x29, x30, [sp, #-16]!
+ bl _exception_entry
+ bl do_error
+ b exception_exit