11da177e4SLinus Torvalds/* 21da177e4SLinus Torvalds * linux/arch/arm/kernel/entry-armv.S 31da177e4SLinus Torvalds * 41da177e4SLinus Torvalds * Copyright (C) 1996,1997,1998 Russell King. 51da177e4SLinus Torvalds * ARM700 fix by Matthew Godbolt (linux-user@willothewisp.demon.co.uk) 61da177e4SLinus Torvalds * 71da177e4SLinus Torvalds * This program is free software; you can redistribute it and/or modify 81da177e4SLinus Torvalds * it under the terms of the GNU General Public License version 2 as 91da177e4SLinus Torvalds * published by the Free Software Foundation. 101da177e4SLinus Torvalds * 111da177e4SLinus Torvalds * Low-level vector interface routines 121da177e4SLinus Torvalds * 131da177e4SLinus Torvalds * Note: there is a StrongARM bug in the STMIA rn, {regs}^ instruction that causes 141da177e4SLinus Torvalds * it to save wrong values... Be aware! 151da177e4SLinus Torvalds */ 161da177e4SLinus Torvalds#include <linux/config.h> 171da177e4SLinus Torvalds 181da177e4SLinus Torvalds#include <asm/glue.h> 191da177e4SLinus Torvalds#include <asm/vfpmacros.h> 20bce495d8SRussell King#include <asm/hardware.h> @ should be moved into entry-macro.S 21bce495d8SRussell King#include <asm/arch/irqs.h> @ should be moved into entry-macro.S 22bce495d8SRussell King#include <asm/arch/entry-macro.S> 231da177e4SLinus Torvalds 241da177e4SLinus Torvalds#include "entry-header.S" 251da177e4SLinus Torvalds 261da177e4SLinus Torvalds/* 271da177e4SLinus Torvalds * Invalid mode handlers 281da177e4SLinus Torvalds */ 291da177e4SLinus Torvalds .macro inv_entry, sym, reason 301da177e4SLinus Torvalds sub sp, sp, #S_FRAME_SIZE @ Allocate frame size in one go 311da177e4SLinus Torvalds stmia sp, {r0 - lr} @ Save XXX r0 - lr 321da177e4SLinus Torvalds ldr r4, .LC\sym 331da177e4SLinus Torvalds mov r1, #\reason 341da177e4SLinus Torvalds .endm 351da177e4SLinus Torvalds 361da177e4SLinus Torvalds__pabt_invalid: 371da177e4SLinus Torvalds inv_entry abt, BAD_PREFETCH 381da177e4SLinus Torvalds b 1f 391da177e4SLinus Torvalds 401da177e4SLinus Torvalds__dabt_invalid: 411da177e4SLinus Torvalds inv_entry abt, BAD_DATA 421da177e4SLinus Torvalds b 1f 431da177e4SLinus Torvalds 441da177e4SLinus Torvalds__irq_invalid: 451da177e4SLinus Torvalds inv_entry irq, BAD_IRQ 461da177e4SLinus Torvalds b 1f 471da177e4SLinus Torvalds 481da177e4SLinus Torvalds__und_invalid: 491da177e4SLinus Torvalds inv_entry und, BAD_UNDEFINSTR 501da177e4SLinus Torvalds 511da177e4SLinus Torvalds1: zero_fp 521da177e4SLinus Torvalds ldmia r4, {r5 - r7} @ Get XXX pc, cpsr, old_r0 531da177e4SLinus Torvalds add r4, sp, #S_PC 541da177e4SLinus Torvalds stmia r4, {r5 - r7} @ Save XXX pc, cpsr, old_r0 551da177e4SLinus Torvalds mov r0, sp 561da177e4SLinus Torvalds and r2, r6, #31 @ int mode 571da177e4SLinus Torvalds b bad_mode 581da177e4SLinus Torvalds 591da177e4SLinus Torvalds/* 601da177e4SLinus Torvalds * SVC mode handlers 611da177e4SLinus Torvalds */ 621da177e4SLinus Torvalds .macro svc_entry, sym 631da177e4SLinus Torvalds sub sp, sp, #S_FRAME_SIZE 641da177e4SLinus Torvalds stmia sp, {r0 - r12} @ save r0 - r12 651da177e4SLinus Torvalds ldr r2, .LC\sym 661da177e4SLinus Torvalds add r0, sp, #S_FRAME_SIZE 671da177e4SLinus Torvalds ldmia r2, {r2 - r4} @ get pc, cpsr 681da177e4SLinus Torvalds add r5, sp, #S_SP 691da177e4SLinus Torvalds mov r1, lr 701da177e4SLinus Torvalds 711da177e4SLinus Torvalds @ 721da177e4SLinus Torvalds @ We are now ready to fill in the remaining blanks on the stack: 731da177e4SLinus Torvalds @ 741da177e4SLinus Torvalds @ r0 - sp_svc 751da177e4SLinus Torvalds @ r1 - lr_svc 761da177e4SLinus Torvalds @ r2 - lr_<exception>, already fixed up for correct return/restart 771da177e4SLinus Torvalds @ r3 - spsr_<exception> 781da177e4SLinus Torvalds @ r4 - orig_r0 (see pt_regs definition in ptrace.h) 791da177e4SLinus Torvalds @ 801da177e4SLinus Torvalds stmia r5, {r0 - r4} 811da177e4SLinus Torvalds .endm 821da177e4SLinus Torvalds 831da177e4SLinus Torvalds .align 5 841da177e4SLinus Torvalds__dabt_svc: 851da177e4SLinus Torvalds svc_entry abt 861da177e4SLinus Torvalds 871da177e4SLinus Torvalds @ 881da177e4SLinus Torvalds @ get ready to re-enable interrupts if appropriate 891da177e4SLinus Torvalds @ 901da177e4SLinus Torvalds mrs r9, cpsr 911da177e4SLinus Torvalds tst r3, #PSR_I_BIT 921da177e4SLinus Torvalds biceq r9, r9, #PSR_I_BIT 931da177e4SLinus Torvalds 941da177e4SLinus Torvalds @ 951da177e4SLinus Torvalds @ Call the processor-specific abort handler: 961da177e4SLinus Torvalds @ 971da177e4SLinus Torvalds @ r2 - aborted context pc 981da177e4SLinus Torvalds @ r3 - aborted context cpsr 991da177e4SLinus Torvalds @ 1001da177e4SLinus Torvalds @ The abort handler must return the aborted address in r0, and 1011da177e4SLinus Torvalds @ the fault status register in r1. r9 must be preserved. 1021da177e4SLinus Torvalds @ 1031da177e4SLinus Torvalds#ifdef MULTI_ABORT 1041da177e4SLinus Torvalds ldr r4, .LCprocfns 1051da177e4SLinus Torvalds mov lr, pc 1061da177e4SLinus Torvalds ldr pc, [r4] 1071da177e4SLinus Torvalds#else 1081da177e4SLinus Torvalds bl CPU_ABORT_HANDLER 1091da177e4SLinus Torvalds#endif 1101da177e4SLinus Torvalds 1111da177e4SLinus Torvalds @ 1121da177e4SLinus Torvalds @ set desired IRQ state, then call main handler 1131da177e4SLinus Torvalds @ 1141da177e4SLinus Torvalds msr cpsr_c, r9 1151da177e4SLinus Torvalds mov r2, sp 1161da177e4SLinus Torvalds bl do_DataAbort 1171da177e4SLinus Torvalds 1181da177e4SLinus Torvalds @ 1191da177e4SLinus Torvalds @ IRQs off again before pulling preserved data off the stack 1201da177e4SLinus Torvalds @ 1211ec42c0cSRussell King disable_irq 1221da177e4SLinus Torvalds 1231da177e4SLinus Torvalds @ 1241da177e4SLinus Torvalds @ restore SPSR and restart the instruction 1251da177e4SLinus Torvalds @ 1261da177e4SLinus Torvalds ldr r0, [sp, #S_PSR] 1271da177e4SLinus Torvalds msr spsr_cxsf, r0 1281da177e4SLinus Torvalds ldmia sp, {r0 - pc}^ @ load r0 - pc, cpsr 1291da177e4SLinus Torvalds 1301da177e4SLinus Torvalds .align 5 1311da177e4SLinus Torvalds__irq_svc: 1321da177e4SLinus Torvalds svc_entry irq 1331da177e4SLinus Torvalds#ifdef CONFIG_PREEMPT 1341da177e4SLinus Torvalds get_thread_info r8 1351da177e4SLinus Torvalds ldr r9, [r8, #TI_PREEMPT] @ get preempt count 1361da177e4SLinus Torvalds add r7, r9, #1 @ increment it 1371da177e4SLinus Torvalds str r7, [r8, #TI_PREEMPT] 1381da177e4SLinus Torvalds#endif 1391da177e4SLinus Torvalds1: get_irqnr_and_base r0, r6, r5, lr 1401da177e4SLinus Torvalds movne r1, sp 1411da177e4SLinus Torvalds @ 1421da177e4SLinus Torvalds @ routine called with r0 = irq number, r1 = struct pt_regs * 1431da177e4SLinus Torvalds @ 1441da177e4SLinus Torvalds adrne lr, 1b 1451da177e4SLinus Torvalds bne asm_do_IRQ 1461da177e4SLinus Torvalds#ifdef CONFIG_PREEMPT 1471da177e4SLinus Torvalds ldr r0, [r8, #TI_FLAGS] @ get flags 1481da177e4SLinus Torvalds tst r0, #_TIF_NEED_RESCHED 1491da177e4SLinus Torvalds blne svc_preempt 1501da177e4SLinus Torvaldspreempt_return: 1511da177e4SLinus Torvalds ldr r0, [r8, #TI_PREEMPT] @ read preempt value 1521da177e4SLinus Torvalds teq r0, r7 1531da177e4SLinus Torvalds str r9, [r8, #TI_PREEMPT] @ restore preempt count 1541da177e4SLinus Torvalds strne r0, [r0, -r0] @ bug() 1551da177e4SLinus Torvalds#endif 1561da177e4SLinus Torvalds ldr r0, [sp, #S_PSR] @ irqs are already disabled 1571da177e4SLinus Torvalds msr spsr_cxsf, r0 1581da177e4SLinus Torvalds ldmia sp, {r0 - pc}^ @ load r0 - pc, cpsr 1591da177e4SLinus Torvalds 1601da177e4SLinus Torvalds .ltorg 1611da177e4SLinus Torvalds 1621da177e4SLinus Torvalds#ifdef CONFIG_PREEMPT 1631da177e4SLinus Torvaldssvc_preempt: 1641da177e4SLinus Torvalds teq r9, #0 @ was preempt count = 0 1651da177e4SLinus Torvalds ldreq r6, .LCirq_stat 1661da177e4SLinus Torvalds movne pc, lr @ no 1671da177e4SLinus Torvalds ldr r0, [r6, #4] @ local_irq_count 1681da177e4SLinus Torvalds ldr r1, [r6, #8] @ local_bh_count 1691da177e4SLinus Torvalds adds r0, r0, r1 1701da177e4SLinus Torvalds movne pc, lr 1711da177e4SLinus Torvalds mov r7, #0 @ preempt_schedule_irq 1721da177e4SLinus Torvalds str r7, [r8, #TI_PREEMPT] @ expects preempt_count == 0 1731da177e4SLinus Torvalds1: bl preempt_schedule_irq @ irq en/disable is done inside 1741da177e4SLinus Torvalds ldr r0, [r8, #TI_FLAGS] @ get new tasks TI_FLAGS 1751da177e4SLinus Torvalds tst r0, #_TIF_NEED_RESCHED 1761da177e4SLinus Torvalds beq preempt_return @ go again 1771da177e4SLinus Torvalds b 1b 1781da177e4SLinus Torvalds#endif 1791da177e4SLinus Torvalds 1801da177e4SLinus Torvalds .align 5 1811da177e4SLinus Torvalds__und_svc: 1821da177e4SLinus Torvalds svc_entry und 1831da177e4SLinus Torvalds 1841da177e4SLinus Torvalds @ 1851da177e4SLinus Torvalds @ call emulation code, which returns using r9 if it has emulated 1861da177e4SLinus Torvalds @ the instruction, or the more conventional lr if we are to treat 1871da177e4SLinus Torvalds @ this as a real undefined instruction 1881da177e4SLinus Torvalds @ 1891da177e4SLinus Torvalds @ r0 - instruction 1901da177e4SLinus Torvalds @ 1911da177e4SLinus Torvalds ldr r0, [r2, #-4] 1921da177e4SLinus Torvalds adr r9, 1f 1931da177e4SLinus Torvalds bl call_fpe 1941da177e4SLinus Torvalds 1951da177e4SLinus Torvalds mov r0, sp @ struct pt_regs *regs 1961da177e4SLinus Torvalds bl do_undefinstr 1971da177e4SLinus Torvalds 1981da177e4SLinus Torvalds @ 1991da177e4SLinus Torvalds @ IRQs off again before pulling preserved data off the stack 2001da177e4SLinus Torvalds @ 2011ec42c0cSRussell King1: disable_irq 2021da177e4SLinus Torvalds 2031da177e4SLinus Torvalds @ 2041da177e4SLinus Torvalds @ restore SPSR and restart the instruction 2051da177e4SLinus Torvalds @ 2061da177e4SLinus Torvalds ldr lr, [sp, #S_PSR] @ Get SVC cpsr 2071da177e4SLinus Torvalds msr spsr_cxsf, lr 2081da177e4SLinus Torvalds ldmia sp, {r0 - pc}^ @ Restore SVC registers 2091da177e4SLinus Torvalds 2101da177e4SLinus Torvalds .align 5 2111da177e4SLinus Torvalds__pabt_svc: 2121da177e4SLinus Torvalds svc_entry abt 2131da177e4SLinus Torvalds 2141da177e4SLinus Torvalds @ 2151da177e4SLinus Torvalds @ re-enable interrupts if appropriate 2161da177e4SLinus Torvalds @ 2171da177e4SLinus Torvalds mrs r9, cpsr 2181da177e4SLinus Torvalds tst r3, #PSR_I_BIT 2191da177e4SLinus Torvalds biceq r9, r9, #PSR_I_BIT 2201da177e4SLinus Torvalds msr cpsr_c, r9 2211da177e4SLinus Torvalds 2221da177e4SLinus Torvalds @ 2231da177e4SLinus Torvalds @ set args, then call main handler 2241da177e4SLinus Torvalds @ 2251da177e4SLinus Torvalds @ r0 - address of faulting instruction 2261da177e4SLinus Torvalds @ r1 - pointer to registers on stack 2271da177e4SLinus Torvalds @ 2281da177e4SLinus Torvalds mov r0, r2 @ address (pc) 2291da177e4SLinus Torvalds mov r1, sp @ regs 2301da177e4SLinus Torvalds bl do_PrefetchAbort @ call abort handler 2311da177e4SLinus Torvalds 2321da177e4SLinus Torvalds @ 2331da177e4SLinus Torvalds @ IRQs off again before pulling preserved data off the stack 2341da177e4SLinus Torvalds @ 2351ec42c0cSRussell King disable_irq 2361da177e4SLinus Torvalds 2371da177e4SLinus Torvalds @ 2381da177e4SLinus Torvalds @ restore SPSR and restart the instruction 2391da177e4SLinus Torvalds @ 2401da177e4SLinus Torvalds ldr r0, [sp, #S_PSR] 2411da177e4SLinus Torvalds msr spsr_cxsf, r0 2421da177e4SLinus Torvalds ldmia sp, {r0 - pc}^ @ load r0 - pc, cpsr 2431da177e4SLinus Torvalds 2441da177e4SLinus Torvalds .align 5 2451da177e4SLinus Torvalds.LCirq: 2461da177e4SLinus Torvalds .word __temp_irq 2471da177e4SLinus Torvalds.LCund: 2481da177e4SLinus Torvalds .word __temp_und 2491da177e4SLinus Torvalds.LCabt: 2501da177e4SLinus Torvalds .word __temp_abt 2511da177e4SLinus Torvalds#ifdef MULTI_ABORT 2521da177e4SLinus Torvalds.LCprocfns: 2531da177e4SLinus Torvalds .word processor 2541da177e4SLinus Torvalds#endif 2551da177e4SLinus Torvalds.LCfp: 2561da177e4SLinus Torvalds .word fp_enter 2571da177e4SLinus Torvalds#ifdef CONFIG_PREEMPT 2581da177e4SLinus Torvalds.LCirq_stat: 2591da177e4SLinus Torvalds .word irq_stat 2601da177e4SLinus Torvalds#endif 2611da177e4SLinus Torvalds 2621da177e4SLinus Torvalds/* 2631da177e4SLinus Torvalds * User mode handlers 2641da177e4SLinus Torvalds */ 2651da177e4SLinus Torvalds .macro usr_entry, sym 2661da177e4SLinus Torvalds sub sp, sp, #S_FRAME_SIZE @ Allocate frame size in one go 2671da177e4SLinus Torvalds stmia sp, {r0 - r12} @ save r0 - r12 2681da177e4SLinus Torvalds ldr r7, .LC\sym 2691da177e4SLinus Torvalds add r5, sp, #S_PC 2701da177e4SLinus Torvalds ldmia r7, {r2 - r4} @ Get USR pc, cpsr 2711da177e4SLinus Torvalds 2722d2669b6SNicolas Pitre#if __LINUX_ARM_ARCH__ < 6 2732d2669b6SNicolas Pitre @ make sure our user space atomic helper is aborted 2742d2669b6SNicolas Pitre cmp r2, #VIRT_OFFSET 2752d2669b6SNicolas Pitre bichs r3, r3, #PSR_Z_BIT 2762d2669b6SNicolas Pitre#endif 2772d2669b6SNicolas Pitre 2781da177e4SLinus Torvalds @ 2791da177e4SLinus Torvalds @ We are now ready to fill in the remaining blanks on the stack: 2801da177e4SLinus Torvalds @ 2811da177e4SLinus Torvalds @ r2 - lr_<exception>, already fixed up for correct return/restart 2821da177e4SLinus Torvalds @ r3 - spsr_<exception> 2831da177e4SLinus Torvalds @ r4 - orig_r0 (see pt_regs definition in ptrace.h) 2841da177e4SLinus Torvalds @ 2851da177e4SLinus Torvalds @ Also, separately save sp_usr and lr_usr 2861da177e4SLinus Torvalds @ 2871da177e4SLinus Torvalds stmia r5, {r2 - r4} 2881da177e4SLinus Torvalds stmdb r5, {sp, lr}^ 2891da177e4SLinus Torvalds 2901da177e4SLinus Torvalds @ 2911da177e4SLinus Torvalds @ Enable the alignment trap while in kernel mode 2921da177e4SLinus Torvalds @ 2931da177e4SLinus Torvalds alignment_trap r7, r0, __temp_\sym 2941da177e4SLinus Torvalds 2951da177e4SLinus Torvalds @ 2961da177e4SLinus Torvalds @ Clear FP to mark the first stack frame 2971da177e4SLinus Torvalds @ 2981da177e4SLinus Torvalds zero_fp 2991da177e4SLinus Torvalds .endm 3001da177e4SLinus Torvalds 3011da177e4SLinus Torvalds .align 5 3021da177e4SLinus Torvalds__dabt_usr: 3031da177e4SLinus Torvalds usr_entry abt 3041da177e4SLinus Torvalds 3051da177e4SLinus Torvalds @ 3061da177e4SLinus Torvalds @ Call the processor-specific abort handler: 3071da177e4SLinus Torvalds @ 3081da177e4SLinus Torvalds @ r2 - aborted context pc 3091da177e4SLinus Torvalds @ r3 - aborted context cpsr 3101da177e4SLinus Torvalds @ 3111da177e4SLinus Torvalds @ The abort handler must return the aborted address in r0, and 3121da177e4SLinus Torvalds @ the fault status register in r1. 3131da177e4SLinus Torvalds @ 3141da177e4SLinus Torvalds#ifdef MULTI_ABORT 3151da177e4SLinus Torvalds ldr r4, .LCprocfns 3161da177e4SLinus Torvalds mov lr, pc 3171da177e4SLinus Torvalds ldr pc, [r4] 3181da177e4SLinus Torvalds#else 3191da177e4SLinus Torvalds bl CPU_ABORT_HANDLER 3201da177e4SLinus Torvalds#endif 3211da177e4SLinus Torvalds 3221da177e4SLinus Torvalds @ 3231da177e4SLinus Torvalds @ IRQs on, then call the main handler 3241da177e4SLinus Torvalds @ 3251ec42c0cSRussell King enable_irq 3261da177e4SLinus Torvalds mov r2, sp 3271da177e4SLinus Torvalds adr lr, ret_from_exception 3281da177e4SLinus Torvalds b do_DataAbort 3291da177e4SLinus Torvalds 3301da177e4SLinus Torvalds .align 5 3311da177e4SLinus Torvalds__irq_usr: 3321da177e4SLinus Torvalds usr_entry irq 3331da177e4SLinus Torvalds 3341da177e4SLinus Torvalds#ifdef CONFIG_PREEMPT 3351da177e4SLinus Torvalds get_thread_info r8 3361da177e4SLinus Torvalds ldr r9, [r8, #TI_PREEMPT] @ get preempt count 3371da177e4SLinus Torvalds add r7, r9, #1 @ increment it 3381da177e4SLinus Torvalds str r7, [r8, #TI_PREEMPT] 3391da177e4SLinus Torvalds#endif 3401da177e4SLinus Torvalds1: get_irqnr_and_base r0, r6, r5, lr 3411da177e4SLinus Torvalds movne r1, sp 3421da177e4SLinus Torvalds adrne lr, 1b 3431da177e4SLinus Torvalds @ 3441da177e4SLinus Torvalds @ routine called with r0 = irq number, r1 = struct pt_regs * 3451da177e4SLinus Torvalds @ 3461da177e4SLinus Torvalds bne asm_do_IRQ 3471da177e4SLinus Torvalds#ifdef CONFIG_PREEMPT 3481da177e4SLinus Torvalds ldr r0, [r8, #TI_PREEMPT] 3491da177e4SLinus Torvalds teq r0, r7 3501da177e4SLinus Torvalds str r9, [r8, #TI_PREEMPT] 3511da177e4SLinus Torvalds strne r0, [r0, -r0] 3521da177e4SLinus Torvalds mov tsk, r8 3531da177e4SLinus Torvalds#else 3541da177e4SLinus Torvalds get_thread_info tsk 3551da177e4SLinus Torvalds#endif 3561da177e4SLinus Torvalds mov why, #0 3571da177e4SLinus Torvalds b ret_to_user 3581da177e4SLinus Torvalds 3591da177e4SLinus Torvalds .ltorg 3601da177e4SLinus Torvalds 3611da177e4SLinus Torvalds .align 5 3621da177e4SLinus Torvalds__und_usr: 3631da177e4SLinus Torvalds usr_entry und 3641da177e4SLinus Torvalds 3651da177e4SLinus Torvalds tst r3, #PSR_T_BIT @ Thumb mode? 3661da177e4SLinus Torvalds bne fpundefinstr @ ignore FP 3671da177e4SLinus Torvalds sub r4, r2, #4 3681da177e4SLinus Torvalds 3691da177e4SLinus Torvalds @ 3701da177e4SLinus Torvalds @ fall through to the emulation code, which returns using r9 if 3711da177e4SLinus Torvalds @ it has emulated the instruction, or the more conventional lr 3721da177e4SLinus Torvalds @ if we are to treat this as a real undefined instruction 3731da177e4SLinus Torvalds @ 3741da177e4SLinus Torvalds @ r0 - instruction 3751da177e4SLinus Torvalds @ 3761da177e4SLinus Torvalds1: ldrt r0, [r4] 3771da177e4SLinus Torvalds adr r9, ret_from_exception 3781da177e4SLinus Torvalds adr lr, fpundefinstr 3791da177e4SLinus Torvalds @ 3801da177e4SLinus Torvalds @ fallthrough to call_fpe 3811da177e4SLinus Torvalds @ 3821da177e4SLinus Torvalds 3831da177e4SLinus Torvalds/* 3841da177e4SLinus Torvalds * The out of line fixup for the ldrt above. 3851da177e4SLinus Torvalds */ 3861da177e4SLinus Torvalds .section .fixup, "ax" 3871da177e4SLinus Torvalds2: mov pc, r9 3881da177e4SLinus Torvalds .previous 3891da177e4SLinus Torvalds .section __ex_table,"a" 3901da177e4SLinus Torvalds .long 1b, 2b 3911da177e4SLinus Torvalds .previous 3921da177e4SLinus Torvalds 3931da177e4SLinus Torvalds/* 3941da177e4SLinus Torvalds * Check whether the instruction is a co-processor instruction. 3951da177e4SLinus Torvalds * If yes, we need to call the relevant co-processor handler. 3961da177e4SLinus Torvalds * 3971da177e4SLinus Torvalds * Note that we don't do a full check here for the co-processor 3981da177e4SLinus Torvalds * instructions; all instructions with bit 27 set are well 3991da177e4SLinus Torvalds * defined. The only instructions that should fault are the 4001da177e4SLinus Torvalds * co-processor instructions. However, we have to watch out 4011da177e4SLinus Torvalds * for the ARM6/ARM7 SWI bug. 4021da177e4SLinus Torvalds * 4031da177e4SLinus Torvalds * Emulators may wish to make use of the following registers: 4041da177e4SLinus Torvalds * r0 = instruction opcode. 4051da177e4SLinus Torvalds * r2 = PC+4 4061da177e4SLinus Torvalds * r10 = this threads thread_info structure. 4071da177e4SLinus Torvalds */ 4081da177e4SLinus Torvaldscall_fpe: 4091da177e4SLinus Torvalds tst r0, #0x08000000 @ only CDP/CPRT/LDC/STC have bit 27 4101da177e4SLinus Torvalds#if defined(CONFIG_CPU_ARM610) || defined(CONFIG_CPU_ARM710) 4111da177e4SLinus Torvalds and r8, r0, #0x0f000000 @ mask out op-code bits 4121da177e4SLinus Torvalds teqne r8, #0x0f000000 @ SWI (ARM6/7 bug)? 4131da177e4SLinus Torvalds#endif 4141da177e4SLinus Torvalds moveq pc, lr 4151da177e4SLinus Torvalds get_thread_info r10 @ get current thread 4161da177e4SLinus Torvalds and r8, r0, #0x00000f00 @ mask out CP number 4171da177e4SLinus Torvalds mov r7, #1 4181da177e4SLinus Torvalds add r6, r10, #TI_USED_CP 4191da177e4SLinus Torvalds strb r7, [r6, r8, lsr #8] @ set appropriate used_cp[] 4201da177e4SLinus Torvalds#ifdef CONFIG_IWMMXT 4211da177e4SLinus Torvalds @ Test if we need to give access to iWMMXt coprocessors 4221da177e4SLinus Torvalds ldr r5, [r10, #TI_FLAGS] 4231da177e4SLinus Torvalds rsbs r7, r8, #(1 << 8) @ CP 0 or 1 only 4241da177e4SLinus Torvalds movcss r7, r5, lsr #(TIF_USING_IWMMXT + 1) 4251da177e4SLinus Torvalds bcs iwmmxt_task_enable 4261da177e4SLinus Torvalds#endif 4271ec42c0cSRussell King enable_irq 4281da177e4SLinus Torvalds add pc, pc, r8, lsr #6 4291da177e4SLinus Torvalds mov r0, r0 4301da177e4SLinus Torvalds 4311da177e4SLinus Torvalds mov pc, lr @ CP#0 4321da177e4SLinus Torvalds b do_fpe @ CP#1 (FPE) 4331da177e4SLinus Torvalds b do_fpe @ CP#2 (FPE) 4341da177e4SLinus Torvalds mov pc, lr @ CP#3 4351da177e4SLinus Torvalds mov pc, lr @ CP#4 4361da177e4SLinus Torvalds mov pc, lr @ CP#5 4371da177e4SLinus Torvalds mov pc, lr @ CP#6 4381da177e4SLinus Torvalds mov pc, lr @ CP#7 4391da177e4SLinus Torvalds mov pc, lr @ CP#8 4401da177e4SLinus Torvalds mov pc, lr @ CP#9 4411da177e4SLinus Torvalds#ifdef CONFIG_VFP 4421da177e4SLinus Torvalds b do_vfp @ CP#10 (VFP) 4431da177e4SLinus Torvalds b do_vfp @ CP#11 (VFP) 4441da177e4SLinus Torvalds#else 4451da177e4SLinus Torvalds mov pc, lr @ CP#10 (VFP) 4461da177e4SLinus Torvalds mov pc, lr @ CP#11 (VFP) 4471da177e4SLinus Torvalds#endif 4481da177e4SLinus Torvalds mov pc, lr @ CP#12 4491da177e4SLinus Torvalds mov pc, lr @ CP#13 4501da177e4SLinus Torvalds mov pc, lr @ CP#14 (Debug) 4511da177e4SLinus Torvalds mov pc, lr @ CP#15 (Control) 4521da177e4SLinus Torvalds 4531da177e4SLinus Torvaldsdo_fpe: 4541da177e4SLinus Torvalds ldr r4, .LCfp 4551da177e4SLinus Torvalds add r10, r10, #TI_FPSTATE @ r10 = workspace 4561da177e4SLinus Torvalds ldr pc, [r4] @ Call FP module USR entry point 4571da177e4SLinus Torvalds 4581da177e4SLinus Torvalds/* 4591da177e4SLinus Torvalds * The FP module is called with these registers set: 4601da177e4SLinus Torvalds * r0 = instruction 4611da177e4SLinus Torvalds * r2 = PC+4 4621da177e4SLinus Torvalds * r9 = normal "successful" return address 4631da177e4SLinus Torvalds * r10 = FP workspace 4641da177e4SLinus Torvalds * lr = unrecognised FP instruction return address 4651da177e4SLinus Torvalds */ 4661da177e4SLinus Torvalds 4671da177e4SLinus Torvalds .data 4681da177e4SLinus TorvaldsENTRY(fp_enter) 4691da177e4SLinus Torvalds .word fpundefinstr 4701da177e4SLinus Torvalds .text 4711da177e4SLinus Torvalds 4721da177e4SLinus Torvaldsfpundefinstr: 4731da177e4SLinus Torvalds mov r0, sp 4741da177e4SLinus Torvalds adr lr, ret_from_exception 4751da177e4SLinus Torvalds b do_undefinstr 4761da177e4SLinus Torvalds 4771da177e4SLinus Torvalds .align 5 4781da177e4SLinus Torvalds__pabt_usr: 4791da177e4SLinus Torvalds usr_entry abt 4801da177e4SLinus Torvalds 4811ec42c0cSRussell King enable_irq @ Enable interrupts 4821da177e4SLinus Torvalds mov r0, r2 @ address (pc) 4831da177e4SLinus Torvalds mov r1, sp @ regs 4841da177e4SLinus Torvalds bl do_PrefetchAbort @ call abort handler 4851da177e4SLinus Torvalds /* fall through */ 4861da177e4SLinus Torvalds/* 4871da177e4SLinus Torvalds * This is the return code to user mode for abort handlers 4881da177e4SLinus Torvalds */ 4891da177e4SLinus TorvaldsENTRY(ret_from_exception) 4901da177e4SLinus Torvalds get_thread_info tsk 4911da177e4SLinus Torvalds mov why, #0 4921da177e4SLinus Torvalds b ret_to_user 4931da177e4SLinus Torvalds 4941da177e4SLinus Torvalds/* 4951da177e4SLinus Torvalds * Register switch for ARMv3 and ARMv4 processors 4961da177e4SLinus Torvalds * r0 = previous task_struct, r1 = previous thread_info, r2 = next thread_info 4971da177e4SLinus Torvalds * previous and next are guaranteed not to be the same. 4981da177e4SLinus Torvalds */ 4991da177e4SLinus TorvaldsENTRY(__switch_to) 5001da177e4SLinus Torvalds add ip, r1, #TI_CPU_SAVE 5011da177e4SLinus Torvalds ldr r3, [r2, #TI_TP_VALUE] 5021da177e4SLinus Torvalds stmia ip!, {r4 - sl, fp, sp, lr} @ Store most regs on stack 5031da177e4SLinus Torvalds ldr r6, [r2, #TI_CPU_DOMAIN]! 5041da177e4SLinus Torvalds#if defined(CONFIG_CPU_XSCALE) && !defined(CONFIG_IWMMXT) 5051da177e4SLinus Torvalds mra r4, r5, acc0 5061da177e4SLinus Torvalds stmia ip, {r4, r5} 5071da177e4SLinus Torvalds#endif 508*4b0e07a5SNicolas Pitre#if defined(CONFIG_HAS_TLS_REG) 5092d2669b6SNicolas Pitre mcr p15, 0, r3, c13, c0, 3 @ set TLS register 510*4b0e07a5SNicolas Pitre#elif !defined(CONFIG_TLS_REG_EMUL) 5111da177e4SLinus Torvalds mov r4, #0xffff0fff 5122d2669b6SNicolas Pitre str r3, [r4, #-15] @ TLS val at 0xffff0ff0 5132d2669b6SNicolas Pitre#endif 5141da177e4SLinus Torvalds mcr p15, 0, r6, c3, c0, 0 @ Set domain register 5151da177e4SLinus Torvalds#ifdef CONFIG_VFP 5161da177e4SLinus Torvalds @ Always disable VFP so we can lazily save/restore the old 5171da177e4SLinus Torvalds @ state. This occurs in the context of the previous thread. 5181da177e4SLinus Torvalds VFPFMRX r4, FPEXC 5191da177e4SLinus Torvalds bic r4, r4, #FPEXC_ENABLE 5201da177e4SLinus Torvalds VFPFMXR FPEXC, r4 5211da177e4SLinus Torvalds#endif 5221da177e4SLinus Torvalds#if defined(CONFIG_IWMMXT) 5231da177e4SLinus Torvalds bl iwmmxt_task_switch 5241da177e4SLinus Torvalds#elif defined(CONFIG_CPU_XSCALE) 5251da177e4SLinus Torvalds add r4, r2, #40 @ cpu_context_save->extra 5261da177e4SLinus Torvalds ldmib r4, {r4, r5} 5271da177e4SLinus Torvalds mar acc0, r4, r5 5281da177e4SLinus Torvalds#endif 5291da177e4SLinus Torvalds ldmib r2, {r4 - sl, fp, sp, pc} @ Load all regs saved previously 5301da177e4SLinus Torvalds 5311da177e4SLinus Torvalds __INIT 5322d2669b6SNicolas Pitre 5332d2669b6SNicolas Pitre/* 5342d2669b6SNicolas Pitre * User helpers. 5352d2669b6SNicolas Pitre * 5362d2669b6SNicolas Pitre * These are segment of kernel provided user code reachable from user space 5372d2669b6SNicolas Pitre * at a fixed address in kernel memory. This is used to provide user space 5382d2669b6SNicolas Pitre * with some operations which require kernel help because of unimplemented 5392d2669b6SNicolas Pitre * native feature and/or instructions in many ARM CPUs. The idea is for 5402d2669b6SNicolas Pitre * this code to be executed directly in user mode for best efficiency but 5412d2669b6SNicolas Pitre * which is too intimate with the kernel counter part to be left to user 5422d2669b6SNicolas Pitre * libraries. In fact this code might even differ from one CPU to another 5432d2669b6SNicolas Pitre * depending on the available instruction set and restrictions like on 5442d2669b6SNicolas Pitre * SMP systems. In other words, the kernel reserves the right to change 5452d2669b6SNicolas Pitre * this code as needed without warning. Only the entry points and their 5462d2669b6SNicolas Pitre * results are guaranteed to be stable. 5472d2669b6SNicolas Pitre * 5482d2669b6SNicolas Pitre * Each segment is 32-byte aligned and will be moved to the top of the high 5492d2669b6SNicolas Pitre * vector page. New segments (if ever needed) must be added in front of 5502d2669b6SNicolas Pitre * existing ones. This mechanism should be used only for things that are 5512d2669b6SNicolas Pitre * really small and justified, and not be abused freely. 5522d2669b6SNicolas Pitre * 5532d2669b6SNicolas Pitre * User space is expected to implement those things inline when optimizing 5542d2669b6SNicolas Pitre * for a processor that has the necessary native support, but only if such 5552d2669b6SNicolas Pitre * resulting binaries are already to be incompatible with earlier ARM 5562d2669b6SNicolas Pitre * processors due to the use of unsupported instructions other than what 5572d2669b6SNicolas Pitre * is provided here. In other words don't make binaries unable to run on 5582d2669b6SNicolas Pitre * earlier processors just for the sake of not using these kernel helpers 5592d2669b6SNicolas Pitre * if your compiled code is not going to use the new instructions for other 5602d2669b6SNicolas Pitre * purpose. 5612d2669b6SNicolas Pitre */ 5622d2669b6SNicolas Pitre 5632d2669b6SNicolas Pitre .align 5 5642d2669b6SNicolas Pitre .globl __kuser_helper_start 5652d2669b6SNicolas Pitre__kuser_helper_start: 5662d2669b6SNicolas Pitre 5672d2669b6SNicolas Pitre/* 5682d2669b6SNicolas Pitre * Reference prototype: 5692d2669b6SNicolas Pitre * 5702d2669b6SNicolas Pitre * int __kernel_cmpxchg(int oldval, int newval, int *ptr) 5712d2669b6SNicolas Pitre * 5722d2669b6SNicolas Pitre * Input: 5732d2669b6SNicolas Pitre * 5742d2669b6SNicolas Pitre * r0 = oldval 5752d2669b6SNicolas Pitre * r1 = newval 5762d2669b6SNicolas Pitre * r2 = ptr 5772d2669b6SNicolas Pitre * lr = return address 5782d2669b6SNicolas Pitre * 5792d2669b6SNicolas Pitre * Output: 5802d2669b6SNicolas Pitre * 5812d2669b6SNicolas Pitre * r0 = returned value (zero or non-zero) 5822d2669b6SNicolas Pitre * C flag = set if r0 == 0, clear if r0 != 0 5832d2669b6SNicolas Pitre * 5842d2669b6SNicolas Pitre * Clobbered: 5852d2669b6SNicolas Pitre * 5862d2669b6SNicolas Pitre * r3, ip, flags 5872d2669b6SNicolas Pitre * 5882d2669b6SNicolas Pitre * Definition and user space usage example: 5892d2669b6SNicolas Pitre * 5902d2669b6SNicolas Pitre * typedef int (__kernel_cmpxchg_t)(int oldval, int newval, int *ptr); 5912d2669b6SNicolas Pitre * #define __kernel_cmpxchg (*(__kernel_cmpxchg_t *)0xffff0fc0) 5922d2669b6SNicolas Pitre * 5932d2669b6SNicolas Pitre * Atomically store newval in *ptr if *ptr is equal to oldval for user space. 5942d2669b6SNicolas Pitre * Return zero if *ptr was changed or non-zero if no exchange happened. 5952d2669b6SNicolas Pitre * The C flag is also set if *ptr was changed to allow for assembly 5962d2669b6SNicolas Pitre * optimization in the calling code. 5972d2669b6SNicolas Pitre * 5982d2669b6SNicolas Pitre * For example, a user space atomic_add implementation could look like this: 5992d2669b6SNicolas Pitre * 6002d2669b6SNicolas Pitre * #define atomic_add(ptr, val) \ 6012d2669b6SNicolas Pitre * ({ register unsigned int *__ptr asm("r2") = (ptr); \ 6022d2669b6SNicolas Pitre * register unsigned int __result asm("r1"); \ 6032d2669b6SNicolas Pitre * asm volatile ( \ 6042d2669b6SNicolas Pitre * "1: @ atomic_add\n\t" \ 6052d2669b6SNicolas Pitre * "ldr r0, [r2]\n\t" \ 6062d2669b6SNicolas Pitre * "mov r3, #0xffff0fff\n\t" \ 6072d2669b6SNicolas Pitre * "add lr, pc, #4\n\t" \ 6082d2669b6SNicolas Pitre * "add r1, r0, %2\n\t" \ 6092d2669b6SNicolas Pitre * "add pc, r3, #(0xffff0fc0 - 0xffff0fff)\n\t" \ 6102d2669b6SNicolas Pitre * "bcc 1b" \ 6112d2669b6SNicolas Pitre * : "=&r" (__result) \ 6122d2669b6SNicolas Pitre * : "r" (__ptr), "rIL" (val) \ 6132d2669b6SNicolas Pitre * : "r0","r3","ip","lr","cc","memory" ); \ 6142d2669b6SNicolas Pitre * __result; }) 6152d2669b6SNicolas Pitre */ 6162d2669b6SNicolas Pitre 6172d2669b6SNicolas Pitre__kuser_cmpxchg: @ 0xffff0fc0 6182d2669b6SNicolas Pitre 6192d2669b6SNicolas Pitre#if __LINUX_ARM_ARCH__ < 6 6202d2669b6SNicolas Pitre 6212d2669b6SNicolas Pitre#ifdef CONFIG_SMP /* sanity check */ 6222d2669b6SNicolas Pitre#error "CONFIG_SMP on a machine supporting pre-ARMv6 processors?" 6232d2669b6SNicolas Pitre#endif 6242d2669b6SNicolas Pitre 6252d2669b6SNicolas Pitre /* 6262d2669b6SNicolas Pitre * Theory of operation: 6272d2669b6SNicolas Pitre * 6282d2669b6SNicolas Pitre * We set the Z flag before loading oldval. If ever an exception 6292d2669b6SNicolas Pitre * occurs we can not be sure the loaded value will still be the same 6302d2669b6SNicolas Pitre * when the exception returns, therefore the user exception handler 6312d2669b6SNicolas Pitre * will clear the Z flag whenever the interrupted user code was 6322d2669b6SNicolas Pitre * actually from the kernel address space (see the usr_entry macro). 6332d2669b6SNicolas Pitre * 6342d2669b6SNicolas Pitre * The post-increment on the str is used to prevent a race with an 6352d2669b6SNicolas Pitre * exception happening just after the str instruction which would 6362d2669b6SNicolas Pitre * clear the Z flag although the exchange was done. 6372d2669b6SNicolas Pitre */ 6382d2669b6SNicolas Pitre teq ip, ip @ set Z flag 6392d2669b6SNicolas Pitre ldr ip, [r2] @ load current val 6402d2669b6SNicolas Pitre add r3, r2, #1 @ prepare store ptr 6412d2669b6SNicolas Pitre teqeq ip, r0 @ compare with oldval if still allowed 6422d2669b6SNicolas Pitre streq r1, [r3, #-1]! @ store newval if still allowed 6432d2669b6SNicolas Pitre subs r0, r2, r3 @ if r2 == r3 the str occured 6442d2669b6SNicolas Pitre mov pc, lr 6452d2669b6SNicolas Pitre 6462d2669b6SNicolas Pitre#else 6472d2669b6SNicolas Pitre 6482d2669b6SNicolas Pitre ldrex r3, [r2] 6492d2669b6SNicolas Pitre subs r3, r3, r0 6502d2669b6SNicolas Pitre strexeq r3, r1, [r2] 6512d2669b6SNicolas Pitre rsbs r0, r3, #0 6522d2669b6SNicolas Pitre mov pc, lr 6532d2669b6SNicolas Pitre 6542d2669b6SNicolas Pitre#endif 6552d2669b6SNicolas Pitre 6562d2669b6SNicolas Pitre .align 5 6572d2669b6SNicolas Pitre 6582d2669b6SNicolas Pitre/* 6592d2669b6SNicolas Pitre * Reference prototype: 6602d2669b6SNicolas Pitre * 6612d2669b6SNicolas Pitre * int __kernel_get_tls(void) 6622d2669b6SNicolas Pitre * 6632d2669b6SNicolas Pitre * Input: 6642d2669b6SNicolas Pitre * 6652d2669b6SNicolas Pitre * lr = return address 6662d2669b6SNicolas Pitre * 6672d2669b6SNicolas Pitre * Output: 6682d2669b6SNicolas Pitre * 6692d2669b6SNicolas Pitre * r0 = TLS value 6702d2669b6SNicolas Pitre * 6712d2669b6SNicolas Pitre * Clobbered: 6722d2669b6SNicolas Pitre * 6732d2669b6SNicolas Pitre * the Z flag might be lost 6742d2669b6SNicolas Pitre * 6752d2669b6SNicolas Pitre * Definition and user space usage example: 6762d2669b6SNicolas Pitre * 6772d2669b6SNicolas Pitre * typedef int (__kernel_get_tls_t)(void); 6782d2669b6SNicolas Pitre * #define __kernel_get_tls (*(__kernel_get_tls_t *)0xffff0fe0) 6792d2669b6SNicolas Pitre * 6802d2669b6SNicolas Pitre * Get the TLS value as previously set via the __ARM_NR_set_tls syscall. 6812d2669b6SNicolas Pitre * 6822d2669b6SNicolas Pitre * This could be used as follows: 6832d2669b6SNicolas Pitre * 6842d2669b6SNicolas Pitre * #define __kernel_get_tls() \ 6852d2669b6SNicolas Pitre * ({ register unsigned int __val asm("r0"); \ 6862d2669b6SNicolas Pitre * asm( "mov r0, #0xffff0fff; mov lr, pc; sub pc, r0, #31" \ 6872d2669b6SNicolas Pitre * : "=r" (__val) : : "lr","cc" ); \ 6882d2669b6SNicolas Pitre * __val; }) 6892d2669b6SNicolas Pitre */ 6902d2669b6SNicolas Pitre 6912d2669b6SNicolas Pitre__kuser_get_tls: @ 0xffff0fe0 6922d2669b6SNicolas Pitre 693*4b0e07a5SNicolas Pitre#if !defined(CONFIG_HAS_TLS_REG) && !defined(CONFIG_TLS_REG_EMUL) 6942d2669b6SNicolas Pitre 6952d2669b6SNicolas Pitre ldr r0, [pc, #(16 - 8)] @ TLS stored at 0xffff0ff0 6962d2669b6SNicolas Pitre mov pc, lr 6972d2669b6SNicolas Pitre 6982d2669b6SNicolas Pitre#else 6992d2669b6SNicolas Pitre 7002d2669b6SNicolas Pitre mrc p15, 0, r0, c13, c0, 3 @ read TLS register 7012d2669b6SNicolas Pitre mov pc, lr 7022d2669b6SNicolas Pitre 7032d2669b6SNicolas Pitre#endif 7042d2669b6SNicolas Pitre 7052d2669b6SNicolas Pitre .rep 5 7062d2669b6SNicolas Pitre .word 0 @ pad up to __kuser_helper_version 7072d2669b6SNicolas Pitre .endr 7082d2669b6SNicolas Pitre 7092d2669b6SNicolas Pitre/* 7102d2669b6SNicolas Pitre * Reference declaration: 7112d2669b6SNicolas Pitre * 7122d2669b6SNicolas Pitre * extern unsigned int __kernel_helper_version; 7132d2669b6SNicolas Pitre * 7142d2669b6SNicolas Pitre * Definition and user space usage example: 7152d2669b6SNicolas Pitre * 7162d2669b6SNicolas Pitre * #define __kernel_helper_version (*(unsigned int *)0xffff0ffc) 7172d2669b6SNicolas Pitre * 7182d2669b6SNicolas Pitre * User space may read this to determine the curent number of helpers 7192d2669b6SNicolas Pitre * available. 7202d2669b6SNicolas Pitre */ 7212d2669b6SNicolas Pitre 7222d2669b6SNicolas Pitre__kuser_helper_version: @ 0xffff0ffc 7232d2669b6SNicolas Pitre .word ((__kuser_helper_end - __kuser_helper_start) >> 5) 7242d2669b6SNicolas Pitre 7252d2669b6SNicolas Pitre .globl __kuser_helper_end 7262d2669b6SNicolas Pitre__kuser_helper_end: 7272d2669b6SNicolas Pitre 7282d2669b6SNicolas Pitre 7291da177e4SLinus Torvalds/* 7301da177e4SLinus Torvalds * Vector stubs. 7311da177e4SLinus Torvalds * 7327933523dSRussell King * This code is copied to 0xffff0200 so we can use branches in the 7337933523dSRussell King * vectors, rather than ldr's. Note that this code must not 7347933523dSRussell King * exceed 0x300 bytes. 7351da177e4SLinus Torvalds * 7361da177e4SLinus Torvalds * Common stub entry macro: 7371da177e4SLinus Torvalds * Enter in IRQ mode, spsr = SVC/USR CPSR, lr = SVC/USR PC 7381da177e4SLinus Torvalds */ 7391da177e4SLinus Torvalds .macro vector_stub, name, sym, correction=0 7401da177e4SLinus Torvalds .align 5 7411da177e4SLinus Torvalds 7421da177e4SLinus Torvaldsvector_\name: 7431da177e4SLinus Torvalds ldr r13, .LCs\sym 7441da177e4SLinus Torvalds .if \correction 7451da177e4SLinus Torvalds sub lr, lr, #\correction 7461da177e4SLinus Torvalds .endif 7471da177e4SLinus Torvalds str lr, [r13] @ save lr_IRQ 7481da177e4SLinus Torvalds mrs lr, spsr 7491da177e4SLinus Torvalds str lr, [r13, #4] @ save spsr_IRQ 7501da177e4SLinus Torvalds @ 7511da177e4SLinus Torvalds @ now branch to the relevant MODE handling routine 7521da177e4SLinus Torvalds @ 7531da177e4SLinus Torvalds mrs r13, cpsr 7541da177e4SLinus Torvalds bic r13, r13, #MODE_MASK 755acaca3c9SRussell King orr r13, r13, #SVC_MODE 7561da177e4SLinus Torvalds msr spsr_cxsf, r13 @ switch to SVC_32 mode 7571da177e4SLinus Torvalds 7581da177e4SLinus Torvalds and lr, lr, #15 7591da177e4SLinus Torvalds ldr lr, [pc, lr, lsl #2] 7601da177e4SLinus Torvalds movs pc, lr @ Changes mode and branches 7611da177e4SLinus Torvalds .endm 7621da177e4SLinus Torvalds 7637933523dSRussell King .globl __stubs_start 7641da177e4SLinus Torvalds__stubs_start: 7651da177e4SLinus Torvalds/* 7661da177e4SLinus Torvalds * Interrupt dispatcher 7671da177e4SLinus Torvalds */ 7681da177e4SLinus Torvalds vector_stub irq, irq, 4 7691da177e4SLinus Torvalds 7701da177e4SLinus Torvalds .long __irq_usr @ 0 (USR_26 / USR_32) 7711da177e4SLinus Torvalds .long __irq_invalid @ 1 (FIQ_26 / FIQ_32) 7721da177e4SLinus Torvalds .long __irq_invalid @ 2 (IRQ_26 / IRQ_32) 7731da177e4SLinus Torvalds .long __irq_svc @ 3 (SVC_26 / SVC_32) 7741da177e4SLinus Torvalds .long __irq_invalid @ 4 7751da177e4SLinus Torvalds .long __irq_invalid @ 5 7761da177e4SLinus Torvalds .long __irq_invalid @ 6 7771da177e4SLinus Torvalds .long __irq_invalid @ 7 7781da177e4SLinus Torvalds .long __irq_invalid @ 8 7791da177e4SLinus Torvalds .long __irq_invalid @ 9 7801da177e4SLinus Torvalds .long __irq_invalid @ a 7811da177e4SLinus Torvalds .long __irq_invalid @ b 7821da177e4SLinus Torvalds .long __irq_invalid @ c 7831da177e4SLinus Torvalds .long __irq_invalid @ d 7841da177e4SLinus Torvalds .long __irq_invalid @ e 7851da177e4SLinus Torvalds .long __irq_invalid @ f 7861da177e4SLinus Torvalds 7871da177e4SLinus Torvalds/* 7881da177e4SLinus Torvalds * Data abort dispatcher 7891da177e4SLinus Torvalds * Enter in ABT mode, spsr = USR CPSR, lr = USR PC 7901da177e4SLinus Torvalds */ 7911da177e4SLinus Torvalds vector_stub dabt, abt, 8 7921da177e4SLinus Torvalds 7931da177e4SLinus Torvalds .long __dabt_usr @ 0 (USR_26 / USR_32) 7941da177e4SLinus Torvalds .long __dabt_invalid @ 1 (FIQ_26 / FIQ_32) 7951da177e4SLinus Torvalds .long __dabt_invalid @ 2 (IRQ_26 / IRQ_32) 7961da177e4SLinus Torvalds .long __dabt_svc @ 3 (SVC_26 / SVC_32) 7971da177e4SLinus Torvalds .long __dabt_invalid @ 4 7981da177e4SLinus Torvalds .long __dabt_invalid @ 5 7991da177e4SLinus Torvalds .long __dabt_invalid @ 6 8001da177e4SLinus Torvalds .long __dabt_invalid @ 7 8011da177e4SLinus Torvalds .long __dabt_invalid @ 8 8021da177e4SLinus Torvalds .long __dabt_invalid @ 9 8031da177e4SLinus Torvalds .long __dabt_invalid @ a 8041da177e4SLinus Torvalds .long __dabt_invalid @ b 8051da177e4SLinus Torvalds .long __dabt_invalid @ c 8061da177e4SLinus Torvalds .long __dabt_invalid @ d 8071da177e4SLinus Torvalds .long __dabt_invalid @ e 8081da177e4SLinus Torvalds .long __dabt_invalid @ f 8091da177e4SLinus Torvalds 8101da177e4SLinus Torvalds/* 8111da177e4SLinus Torvalds * Prefetch abort dispatcher 8121da177e4SLinus Torvalds * Enter in ABT mode, spsr = USR CPSR, lr = USR PC 8131da177e4SLinus Torvalds */ 8141da177e4SLinus Torvalds vector_stub pabt, abt, 4 8151da177e4SLinus Torvalds 8161da177e4SLinus Torvalds .long __pabt_usr @ 0 (USR_26 / USR_32) 8171da177e4SLinus Torvalds .long __pabt_invalid @ 1 (FIQ_26 / FIQ_32) 8181da177e4SLinus Torvalds .long __pabt_invalid @ 2 (IRQ_26 / IRQ_32) 8191da177e4SLinus Torvalds .long __pabt_svc @ 3 (SVC_26 / SVC_32) 8201da177e4SLinus Torvalds .long __pabt_invalid @ 4 8211da177e4SLinus Torvalds .long __pabt_invalid @ 5 8221da177e4SLinus Torvalds .long __pabt_invalid @ 6 8231da177e4SLinus Torvalds .long __pabt_invalid @ 7 8241da177e4SLinus Torvalds .long __pabt_invalid @ 8 8251da177e4SLinus Torvalds .long __pabt_invalid @ 9 8261da177e4SLinus Torvalds .long __pabt_invalid @ a 8271da177e4SLinus Torvalds .long __pabt_invalid @ b 8281da177e4SLinus Torvalds .long __pabt_invalid @ c 8291da177e4SLinus Torvalds .long __pabt_invalid @ d 8301da177e4SLinus Torvalds .long __pabt_invalid @ e 8311da177e4SLinus Torvalds .long __pabt_invalid @ f 8321da177e4SLinus Torvalds 8331da177e4SLinus Torvalds/* 8341da177e4SLinus Torvalds * Undef instr entry dispatcher 8351da177e4SLinus Torvalds * Enter in UND mode, spsr = SVC/USR CPSR, lr = SVC/USR PC 8361da177e4SLinus Torvalds */ 8371da177e4SLinus Torvalds vector_stub und, und 8381da177e4SLinus Torvalds 8391da177e4SLinus Torvalds .long __und_usr @ 0 (USR_26 / USR_32) 8401da177e4SLinus Torvalds .long __und_invalid @ 1 (FIQ_26 / FIQ_32) 8411da177e4SLinus Torvalds .long __und_invalid @ 2 (IRQ_26 / IRQ_32) 8421da177e4SLinus Torvalds .long __und_svc @ 3 (SVC_26 / SVC_32) 8431da177e4SLinus Torvalds .long __und_invalid @ 4 8441da177e4SLinus Torvalds .long __und_invalid @ 5 8451da177e4SLinus Torvalds .long __und_invalid @ 6 8461da177e4SLinus Torvalds .long __und_invalid @ 7 8471da177e4SLinus Torvalds .long __und_invalid @ 8 8481da177e4SLinus Torvalds .long __und_invalid @ 9 8491da177e4SLinus Torvalds .long __und_invalid @ a 8501da177e4SLinus Torvalds .long __und_invalid @ b 8511da177e4SLinus Torvalds .long __und_invalid @ c 8521da177e4SLinus Torvalds .long __und_invalid @ d 8531da177e4SLinus Torvalds .long __und_invalid @ e 8541da177e4SLinus Torvalds .long __und_invalid @ f 8551da177e4SLinus Torvalds 8561da177e4SLinus Torvalds .align 5 8571da177e4SLinus Torvalds 8581da177e4SLinus Torvalds/*============================================================================= 8591da177e4SLinus Torvalds * Undefined FIQs 8601da177e4SLinus Torvalds *----------------------------------------------------------------------------- 8611da177e4SLinus Torvalds * Enter in FIQ mode, spsr = ANY CPSR, lr = ANY PC 8621da177e4SLinus Torvalds * MUST PRESERVE SVC SPSR, but need to switch to SVC mode to show our msg. 8631da177e4SLinus Torvalds * Basically to switch modes, we *HAVE* to clobber one register... brain 8641da177e4SLinus Torvalds * damage alert! I don't think that we can execute any code in here in any 8651da177e4SLinus Torvalds * other mode than FIQ... Ok you can switch to another mode, but you can't 8661da177e4SLinus Torvalds * get out of that mode without clobbering one register. 8671da177e4SLinus Torvalds */ 8681da177e4SLinus Torvaldsvector_fiq: 8691da177e4SLinus Torvalds disable_fiq 8701da177e4SLinus Torvalds subs pc, lr, #4 8711da177e4SLinus Torvalds 8721da177e4SLinus Torvalds/*============================================================================= 8731da177e4SLinus Torvalds * Address exception handler 8741da177e4SLinus Torvalds *----------------------------------------------------------------------------- 8751da177e4SLinus Torvalds * These aren't too critical. 8761da177e4SLinus Torvalds * (they're not supposed to happen, and won't happen in 32-bit data mode). 8771da177e4SLinus Torvalds */ 8781da177e4SLinus Torvalds 8791da177e4SLinus Torvaldsvector_addrexcptn: 8801da177e4SLinus Torvalds b vector_addrexcptn 8811da177e4SLinus Torvalds 8821da177e4SLinus Torvalds/* 8831da177e4SLinus Torvalds * We group all the following data together to optimise 8841da177e4SLinus Torvalds * for CPUs with separate I & D caches. 8851da177e4SLinus Torvalds */ 8861da177e4SLinus Torvalds .align 5 8871da177e4SLinus Torvalds 8881da177e4SLinus Torvalds.LCvswi: 8891da177e4SLinus Torvalds .word vector_swi 8901da177e4SLinus Torvalds 8911da177e4SLinus Torvalds.LCsirq: 8921da177e4SLinus Torvalds .word __temp_irq 8931da177e4SLinus Torvalds.LCsund: 8941da177e4SLinus Torvalds .word __temp_und 8951da177e4SLinus Torvalds.LCsabt: 8961da177e4SLinus Torvalds .word __temp_abt 8971da177e4SLinus Torvalds 8987933523dSRussell King .globl __stubs_end 8991da177e4SLinus Torvalds__stubs_end: 9001da177e4SLinus Torvalds 9017933523dSRussell King .equ stubs_offset, __vectors_start + 0x200 - __stubs_start 9021da177e4SLinus Torvalds 9037933523dSRussell King .globl __vectors_start 9047933523dSRussell King__vectors_start: 9051da177e4SLinus Torvalds swi SYS_ERROR0 9067933523dSRussell King b vector_und + stubs_offset 9077933523dSRussell King ldr pc, .LCvswi + stubs_offset 9087933523dSRussell King b vector_pabt + stubs_offset 9097933523dSRussell King b vector_dabt + stubs_offset 9107933523dSRussell King b vector_addrexcptn + stubs_offset 9117933523dSRussell King b vector_irq + stubs_offset 9127933523dSRussell King b vector_fiq + stubs_offset 9131da177e4SLinus Torvalds 9147933523dSRussell King .globl __vectors_end 9157933523dSRussell King__vectors_end: 9161da177e4SLinus Torvalds 9171da177e4SLinus Torvalds .data 9181da177e4SLinus Torvalds 9191da177e4SLinus Torvalds/* 9201da177e4SLinus Torvalds * Do not reorder these, and do not insert extra data between... 9211da177e4SLinus Torvalds */ 9221da177e4SLinus Torvalds 9231da177e4SLinus Torvalds__temp_irq: 9241da177e4SLinus Torvalds .word 0 @ saved lr_irq 9251da177e4SLinus Torvalds .word 0 @ saved spsr_irq 9261da177e4SLinus Torvalds .word -1 @ old_r0 9271da177e4SLinus Torvalds__temp_und: 9281da177e4SLinus Torvalds .word 0 @ Saved lr_und 9291da177e4SLinus Torvalds .word 0 @ Saved spsr_und 9301da177e4SLinus Torvalds .word -1 @ old_r0 9311da177e4SLinus Torvalds__temp_abt: 9321da177e4SLinus Torvalds .word 0 @ Saved lr_abt 9331da177e4SLinus Torvalds .word 0 @ Saved spsr_abt 9341da177e4SLinus Torvalds .word -1 @ old_r0 9351da177e4SLinus Torvalds 9361da177e4SLinus Torvalds .globl cr_alignment 9371da177e4SLinus Torvalds .globl cr_no_alignment 9381da177e4SLinus Torvaldscr_alignment: 9391da177e4SLinus Torvalds .space 4 9401da177e4SLinus Torvaldscr_no_alignment: 9411da177e4SLinus Torvalds .space 4 942