diff options
Diffstat (limited to 'arch/arm/kernel')
| -rw-r--r-- | arch/arm/kernel/Makefile | 3 | ||||
| -rw-r--r-- | arch/arm/kernel/asm-offsets.c | 10 | ||||
| -rw-r--r-- | arch/arm/kernel/calls.S | 6 | ||||
| -rw-r--r-- | arch/arm/kernel/entry-armv.S | 111 | ||||
| -rw-r--r-- | arch/arm/kernel/entry-common.S | 5 | ||||
| -rw-r--r-- | arch/arm/kernel/head-common.S | 10 | ||||
| -rw-r--r-- | arch/arm/kernel/head.S | 3 | ||||
| -rw-r--r-- | arch/arm/kernel/kprobes.c | 5 | ||||
| -rw-r--r-- | arch/arm/kernel/semaphore.c | 221 | ||||
| -rw-r--r-- | arch/arm/kernel/signal.c | 4 | ||||
| -rw-r--r-- | arch/arm/kernel/sys_oabi-compat.c | 24 | ||||
| -rw-r--r-- | arch/arm/kernel/thumbee.c | 81 |
12 files changed, 215 insertions, 268 deletions
diff --git a/arch/arm/kernel/Makefile b/arch/arm/kernel/Makefile index 00d44c6fbfe9..ad455ff5aebe 100644 --- a/arch/arm/kernel/Makefile +++ b/arch/arm/kernel/Makefile @@ -7,7 +7,7 @@ AFLAGS_head.o := -DTEXT_OFFSET=$(TEXT_OFFSET) # Object file lists. obj-y := compat.o entry-armv.o entry-common.o irq.o \ - process.o ptrace.o semaphore.o setup.o signal.o \ + process.o ptrace.o setup.o signal.o \ sys_arm.o stacktrace.o time.o traps.o obj-$(CONFIG_ISA_DMA_API) += dma.o @@ -22,6 +22,7 @@ obj-$(CONFIG_KEXEC) += machine_kexec.o relocate_kernel.o obj-$(CONFIG_KPROBES) += kprobes.o kprobes-decode.o obj-$(CONFIG_ATAGS_PROC) += atags.o obj-$(CONFIG_OABI_COMPAT) += sys_oabi-compat.o +obj-$(CONFIG_ARM_THUMBEE) += thumbee.o obj-$(CONFIG_CRUNCH) += crunch.o crunch-bits.o AFLAGS_crunch-bits.o := -Wa,-mcpu=ep9312 diff --git a/arch/arm/kernel/asm-offsets.c b/arch/arm/kernel/asm-offsets.c index 3278e713c32a..0a0d2479274b 100644 --- a/arch/arm/kernel/asm-offsets.c +++ b/arch/arm/kernel/asm-offsets.c @@ -58,6 +58,9 @@ int main(void) DEFINE(TI_TP_VALUE, offsetof(struct thread_info, tp_value)); DEFINE(TI_FPSTATE, offsetof(struct thread_info, fpstate)); DEFINE(TI_VFPSTATE, offsetof(struct thread_info, vfpstate)); +#ifdef CONFIG_ARM_THUMBEE + DEFINE(TI_THUMBEE_STATE, offsetof(struct thread_info, thumbee_state)); +#endif #ifdef CONFIG_IWMMXT DEFINE(TI_IWMMXT_STATE, offsetof(struct thread_info, fpstate.iwmmxt)); #endif @@ -108,5 +111,12 @@ int main(void) DEFINE(PROCINFO_INITFUNC, offsetof(struct proc_info_list, __cpu_flush)); DEFINE(PROCINFO_MM_MMUFLAGS, offsetof(struct proc_info_list, __cpu_mm_mmu_flags)); DEFINE(PROCINFO_IO_MMUFLAGS, offsetof(struct proc_info_list, __cpu_io_mmu_flags)); + BLANK(); +#ifdef MULTI_DABORT + DEFINE(PROCESSOR_DABT_FUNC, offsetof(struct processor, _data_abort)); +#endif +#ifdef MULTI_PABORT + DEFINE(PROCESSOR_PABT_FUNC, offsetof(struct processor, _prefetch_abort)); +#endif return 0; } diff --git a/arch/arm/kernel/calls.S b/arch/arm/kernel/calls.S index 283e14fff993..30a67a5a40a8 100644 --- a/arch/arm/kernel/calls.S +++ b/arch/arm/kernel/calls.S @@ -336,7 +336,7 @@ CALL(sys_mknodat) /* 325 */ CALL(sys_fchownat) CALL(sys_futimesat) - CALL(sys_fstatat64) + CALL(ABI(sys_fstatat64, sys_oabi_fstatat64)) CALL(sys_unlinkat) CALL(sys_renameat) /* 330 */ CALL(sys_linkat) @@ -359,9 +359,11 @@ CALL(sys_kexec_load) CALL(sys_utimensat) CALL(sys_signalfd) -/* 350 */ CALL(sys_ni_syscall) +/* 350 */ CALL(sys_timerfd_create) CALL(sys_eventfd) CALL(sys_fallocate) + CALL(sys_timerfd_settime) + CALL(sys_timerfd_gettime) #ifndef syscalls_counted .equ syscalls_padding, ((NR_syscalls + 3) & ~3) - NR_syscalls #define syscalls_counted diff --git a/arch/arm/kernel/entry-armv.S b/arch/arm/kernel/entry-armv.S index a46d5b456765..7dca225752c1 100644 --- a/arch/arm/kernel/entry-armv.S +++ b/arch/arm/kernel/entry-armv.S @@ -166,12 +166,12 @@ __dabt_svc: @ The abort handler must return the aborted address in r0, and @ the fault status register in r1. r9 must be preserved. @ -#ifdef MULTI_ABORT +#ifdef MULTI_DABORT ldr r4, .LCprocfns mov lr, pc - ldr pc, [r4] + ldr pc, [r4, #PROCESSOR_DABT_FUNC] #else - bl CPU_ABORT_HANDLER + bl CPU_DABORT_HANDLER #endif @ @@ -209,14 +209,12 @@ __irq_svc: irq_handler #ifdef CONFIG_PREEMPT + str r8, [tsk, #TI_PREEMPT] @ restore preempt count ldr r0, [tsk, #TI_FLAGS] @ get flags + teq r8, #0 @ if preempt count != 0 + movne r0, #0 @ force flags to 0 tst r0, #_TIF_NEED_RESCHED blne svc_preempt -preempt_return: - ldr r0, [tsk, #TI_PREEMPT] @ read preempt value - str r8, [tsk, #TI_PREEMPT] @ restore preempt count - teq r0, r7 - strne r0, [r0, -r0] @ bug() #endif ldr r0, [sp, #S_PSR] @ irqs are already disabled msr spsr_cxsf, r0 @@ -230,19 +228,11 @@ preempt_return: #ifdef CONFIG_PREEMPT svc_preempt: - teq r8, #0 @ was preempt count = 0 - ldreq r6, .LCirq_stat - movne pc, lr @ no - ldr r0, [r6, #4] @ local_irq_count - ldr r1, [r6, #8] @ local_bh_count - adds r0, r0, r1 - movne pc, lr - mov r7, #0 @ preempt_schedule_irq - str r7, [tsk, #TI_PREEMPT] @ expects preempt_count == 0 + mov r8, lr 1: bl preempt_schedule_irq @ irq en/disable is done inside ldr r0, [tsk, #TI_FLAGS] @ get new tasks TI_FLAGS tst r0, #_TIF_NEED_RESCHED - beq preempt_return @ go again + moveq pc, r8 @ go again b 1b #endif @@ -293,7 +283,6 @@ __pabt_svc: mrs r9, cpsr tst r3, #PSR_I_BIT biceq r9, r9, #PSR_I_BIT - msr cpsr_c, r9 @ @ set args, then call main handler @@ -301,7 +290,15 @@ __pabt_svc: @ r0 - address of faulting instruction @ r1 - pointer to registers on stack @ - mov r0, r2 @ address (pc) +#ifdef MULTI_PABORT + mov r0, r2 @ pass address of aborted instruction. + ldr r4, .LCprocfns + mov lr, pc + ldr pc, [r4, #PROCESSOR_PABT_FUNC] +#else + CPU_PABORT_HANDLER(r0, r2) +#endif + msr cpsr_c, r9 @ Maybe enable interrupts mov r1, sp @ regs bl do_PrefetchAbort @ call abort handler @@ -320,16 +317,12 @@ __pabt_svc: .align 5 .LCcralign: .word cr_alignment -#ifdef MULTI_ABORT +#ifdef MULTI_DABORT .LCprocfns: .word processor #endif .LCfp: .word fp_enter -#ifdef CONFIG_PREEMPT -.LCirq_stat: - .word irq_stat -#endif /* * User mode handlers @@ -404,12 +397,12 @@ __dabt_usr: @ The abort handler must return the aborted address in r0, and @ the fault status register in r1. @ -#ifdef MULTI_ABORT +#ifdef MULTI_DABORT ldr r4, .LCprocfns mov lr, pc - ldr pc, [r4] + ldr pc, [r4, #PROCESSOR_DABT_FUNC] #else - bl CPU_ABORT_HANDLER + bl CPU_DABORT_HANDLER #endif @ @@ -455,10 +448,6 @@ __irq_usr: __und_usr: usr_entry - tst r3, #PSR_T_BIT @ Thumb mode? - bne __und_usr_unknown @ ignore FP - sub r4, r2, #4 - @ @ fall through to the emulation code, which returns using r9 if @ it has emulated the instruction, or the more conventional lr @@ -468,7 +457,24 @@ __und_usr: @ adr r9, ret_from_exception adr lr, __und_usr_unknown -1: ldrt r0, [r4] + tst r3, #PSR_T_BIT @ Thumb mode? + subeq r4, r2, #4 @ ARM instr at LR - 4 + subne r4, r2, #2 @ Thumb instr at LR - 2 +1: ldreqt r0, [r4] + beq call_fpe + @ Thumb instruction +#if __LINUX_ARM_ARCH__ >= 7 +2: ldrht r5, [r4], #2 + and r0, r5, #0xf800 @ mask bits 111x x... .... .... + cmp r0, #0xe800 @ 32bit instruction if xx != 0 + blo __und_usr_unknown +3: ldrht r0, [r4] + add r2, r2, #2 @ r2 is PC + 2, make it PC + 4 + orr r0, r0, r5, lsl #16 +#else + b __und_usr_unknown +#endif + @ @ fallthrough to call_fpe @ @@ -477,10 +483,14 @@ __und_usr: * The out of line fixup for the ldrt above. */ .section .fixup, "ax" -2: mov pc, r9 +4: mov pc, r9 .previous .section __ex_table,"a" - .long 1b, 2b + .long 1b, 4b +#if __LINUX_ARM_ARCH__ >= 7 + .long 2b, 4b + .long 3b, 4b +#endif .previous /* @@ -507,9 +517,16 @@ __und_usr: * r10 = this threads thread_info structure. * lr = unrecognised instruction return address */ + @ + @ Fall-through from Thumb-2 __und_usr + @ +#ifdef CONFIG_NEON + adr r6, .LCneon_thumb_opcodes + b 2f +#endif call_fpe: #ifdef CONFIG_NEON - adr r6, .LCneon_opcodes + adr r6, .LCneon_arm_opcodes 2: ldr r7, [r6], #4 @ mask value cmp r7, #0 @ end mask? @@ -526,6 +543,7 @@ call_fpe: 1: #endif tst r0, #0x08000000 @ only CDP/CPRT/LDC/STC have bit 27 + tstne r0, #0x04000000 @ bit 26 set on both ARM and Thumb-2 #if defined(CONFIG_CPU_ARM610) || defined(CONFIG_CPU_ARM710) and r8, r0, #0x0f000000 @ mask out op-code bits teqne r8, #0x0f000000 @ SWI (ARM6/7 bug)? @@ -577,7 +595,7 @@ call_fpe: #ifdef CONFIG_NEON .align 6 -.LCneon_opcodes: +.LCneon_arm_opcodes: .word 0xfe000000 @ mask .word 0xf2000000 @ opcode @@ -586,6 +604,16 @@ call_fpe: .word 0x00000000 @ mask .word 0x00000000 @ opcode + +.LCneon_thumb_opcodes: + .word 0xef000000 @ mask + .word 0xef000000 @ opcode + + .word 0xff100000 @ mask + .word 0xf9000000 @ opcode + + .word 0x00000000 @ mask + .word 0x00000000 @ opcode #endif do_fpe: @@ -619,8 +647,15 @@ __und_usr_unknown: __pabt_usr: usr_entry +#ifdef MULTI_PABORT + mov r0, r2 @ pass address of aborted instruction. + ldr r4, .LCprocfns + mov lr, pc + ldr pc, [r4, #PROCESSOR_PABT_FUNC] +#else + CPU_PABORT_HANDLER(r0, r2) +#endif enable_irq @ Enable interrupts - mov r0, r2 @ address (pc) mov r1, sp @ regs bl do_PrefetchAbort @ call abort handler /* fall through */ diff --git a/arch/arm/kernel/entry-common.S b/arch/arm/kernel/entry-common.S index 6c90c50a9ee3..597ed00a08d8 100644 --- a/arch/arm/kernel/entry-common.S +++ b/arch/arm/kernel/entry-common.S @@ -352,6 +352,11 @@ sys_mmap2: b do_mmap2 #endif +ENTRY(pabort_ifar) + mrc p15, 0, r0, cr6, cr0, 2 +ENTRY(pabort_noifar) + mov pc, lr + #ifdef CONFIG_OABI_COMPAT /* diff --git a/arch/arm/kernel/head-common.S b/arch/arm/kernel/head-common.S index 024a9cf469b4..7e9c00a8a412 100644 --- a/arch/arm/kernel/head-common.S +++ b/arch/arm/kernel/head-common.S @@ -11,6 +11,9 @@ * */ +#define ATAG_CORE 0x54410001 +#define ATAG_CORE_SIZE ((2*4 + 3*4) >> 2) + .type __switch_data, %object __switch_data: .long __mmap_switched @@ -72,8 +75,13 @@ __error_p: #ifdef CONFIG_DEBUG_LL adr r0, str_p1 bl printascii + mov r0, r9 + bl printhex8 + adr r0, str_p2 + bl printascii b __error -str_p1: .asciz "\nError: unrecognized/unsupported processor variant.\n" +str_p1: .asciz "\nError: unrecognized/unsupported processor variant (0x" +str_p2: .asciz ").\n" .align #endif diff --git a/arch/arm/kernel/head.S b/arch/arm/kernel/head.S index 7898cbc9861a..bff4c6e90dd5 100644 --- a/arch/arm/kernel/head.S +++ b/arch/arm/kernel/head.S @@ -29,9 +29,6 @@ #define KERNEL_RAM_VADDR (PAGE_OFFSET + TEXT_OFFSET) #define KERNEL_RAM_PADDR (PHYS_OFFSET + TEXT_OFFSET) -#define ATAG_CORE 0x54410001 -#define ATAG_CORE_SIZE ((2*4 + 3*4) >> 2) - /* * swapper_pg_dir is the virtual address of the initial page table. diff --git a/arch/arm/kernel/kprobes.c b/arch/arm/kernel/kprobes.c index a22a98c43ca5..13e371aad879 100644 --- a/arch/arm/kernel/kprobes.c +++ b/arch/arm/kernel/kprobes.c @@ -431,6 +431,11 @@ int __kprobes longjmp_break_handler(struct kprobe *p, struct pt_regs *regs) return 0; } +int __kprobes arch_trampoline_kprobe(struct kprobe *p) +{ + return 0; +} + static struct undef_hook kprobes_break_hook = { .instr_mask = 0xffffffff, .instr_val = KPROBE_BREAKPOINT_INSTRUCTION, diff --git a/arch/arm/kernel/semaphore.c b/arch/arm/kernel/semaphore.c deleted file mode 100644 index 981fe5c6ccbe..000000000000 --- a/arch/arm/kernel/semaphore.c +++ /dev/null @@ -1,221 +0,0 @@ -/* - * ARM semaphore implementation, taken from - * - * i386 semaphore implementation. - * - * (C) Copyright 1999 Linus Torvalds - * - * Modified for ARM by Russell King - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License version 2 as - * published by the Free Software Foundation. - */ -#include <linux/module.h> -#include <linux/sched.h> -#include <linux/errno.h> -#include <linux/init.h> - -#include <asm/semaphore.h> - -/* - * Semaphores are implemented using a two-way counter: - * The "count" variable is decremented for each process - * that tries to acquire the semaphore, while the "sleeping" - * variable is a count of such acquires. - * - * Notably, the inline "up()" and "down()" functions can - * efficiently test if they need to do any extra work (up - * needs to do something only if count was negative before - * the increment operation. - * - * "sleeping" and the contention routine ordering is - * protected by the semaphore spinlock. - * - * Note that these functions are only called when there is - * contention on the lock, and as such all this is the - * "non-critical" part of the whole semaphore business. The - * critical part is the inline stuff in <asm/semaphore.h> - * where we want to avoid any extra jumps and calls. - */ - -/* - * Logic: - * - only on a boundary condition do we need to care. When we go - * from a negative count to a non-negative, we wake people up. - * - when we go from a non-negative count to a negative do we - * (a) synchronize with the "sleeper" count and (b) make sure - * that we're on the wakeup list before we synchronize so that - * we cannot lose wakeup events. - */ - -void __up(struct semaphore *sem) -{ - wake_up(&sem->wait); -} - -static DEFINE_SPINLOCK(semaphore_lock); - -void __sched __down(struct semaphore * sem) -{ - struct task_struct *tsk = current; - DECLARE_WAITQUEUE(wait, tsk); - tsk->state = TASK_UNINTERRUPTIBLE; - add_wait_queue_exclusive(&sem->wait, &wait); - - spin_lock_irq(&semaphore_lock); - sem->sleepers++; - for (;;) { - int sleepers = sem->sleepers; - - /* - * Add "everybody else" into it. They aren't - * playing, because we own the spinlock. - */ - if (!atomic_add_negative(sleepers - 1, &sem->count)) { - sem->sleepers = 0; - break; - } - sem->sleepers = 1; /* us - see -1 above */ - spin_unlock_irq(&semaphore_lock); - - schedule(); - tsk->state = TASK_UNINTERRUPTIBLE; - spin_lock_irq(&semaphore_lock); - } - spin_unlock_irq(&semaphore_lock); - remove_wait_queue(&sem->wait, &wait); - tsk->state = TASK_RUNNING; - wake_up(&sem->wait); -} - -int __sched __down_interruptible(struct semaphore * sem) -{ - int retval = 0; - struct task_struct *tsk = current; - DECLARE_WAITQUEUE(wait, tsk); - tsk->state = TASK_INTERRUPTIBLE; - add_wait_queue_exclusive(&sem->wait, &wait); - - spin_lock_irq(&semaphore_lock); - sem->sleepers ++; - for (;;) { - int sleepers = sem->sleepers; - - /* - * With signals pending, this turns into - * the trylock failure case - we won't be - * sleeping, and we* can't get the lock as - * it has contention. Just correct the count - * and exit. - */ - if (signal_pending(current)) { - retval = -EINTR; - sem->sleepers = 0; - atomic_add(sleepers, &sem->count); - break; - } - - /* - * Add "everybody else" into it. They aren't - * playing, because we own the spinlock. The - * "-1" is because we're still hoping to get - * the lock. - */ - if (!atomic_add_negative(sleepers - 1, &sem->count)) { - sem->sleepers = 0; - break; - } - sem->sleepers = 1; /* us - see -1 above */ - spin_unlock_irq(&semaphore_lock); - - schedule(); - tsk->state = TASK_INTERRUPTIBLE; - spin_lock_irq(&semaphore_lock); - } - spin_unlock_irq(&semaphore_lock); - tsk->state = TASK_RUNNING; - remove_wait_queue(&sem->wait, &wait); - wake_up(&sem->wait); - return retval; -} - -/* - * Trylock failed - make sure we correct for - * having decremented the count. - * - * We could have done the trylock with a - * single "cmpxchg" without failure cases, - * but then it wouldn't work on a 386. - */ -int __down_trylock(struct semaphore * sem) -{ - int sleepers; - unsigned long flags; - - spin_lock_irqsave(&semaphore_lock, flags); - sleepers = sem->sleepers + 1; - sem->sleepers = 0; - - /* - * Add "everybody else" and us into it. They aren't - * playing, because we own the spinlock. - */ - if (!atomic_add_negative(sleepers, &sem->count)) - wake_up(&sem->wait); - - spin_unlock_irqrestore(&semaphore_lock, flags); - return 1; -} - -/* - * The semaphore operations have a special calling sequence that - * allow us to do a simpler in-line version of them. These routines - * need to convert that sequence back into the C sequence when - * there is contention on the semaphore. - * - * ip contains the semaphore pointer on entry. Save the C-clobbered - * registers (r0 to r3 and lr), but not ip, as we use it as a return - * value in some cases.. - * To remain AAPCS compliant (64-bit stack align) we save r4 as well. - */ -asm(" .section .sched.text,\"ax\",%progbits \n\ - .align 5 \n\ - .globl __down_failed \n\ -__down_failed: \n\ - stmfd sp!, {r0 - r4, lr} \n\ - mov r0, ip \n\ - bl __down \n\ - ldmfd sp!, {r0 - r4, pc} \n\ - \n\ - .align 5 \n\ - .globl __down_interruptible_failed \n\ -__down_interruptible_failed: \n\ - stmfd sp!, {r0 - r4, lr} \n\ - mov r0, ip \n\ - bl __down_interruptible \n\ - mov ip, r0 \n\ - ldmfd sp!, {r0 - r4, pc} \n\ - \n\ - .align 5 \n\ - .globl __down_trylock_failed \n\ -__down_trylock_failed: \n\ - stmfd sp!, {r0 - r4, lr} \n\ - mov r0, ip \n\ - bl __down_trylock \n\ - mov ip, r0 \n\ - ldmfd sp!, {r0 - r4, pc} \n\ - \n\ - .align 5 \n\ - .globl __up_wakeup \n\ -__up_wakeup: \n\ - stmfd sp!, {r0 - r4, lr} \n\ - mov r0, ip \n\ - bl __up \n\ - ldmfd sp!, {r0 - r4, pc} \n\ - "); - -EXPORT_SYMBOL(__down_failed); -EXPORT_SYMBOL(__down_interruptible_failed); -EXPORT_SYMBOL(__down_trylock_failed); -EXPORT_SYMBOL(__up_wakeup); diff --git a/arch/arm/kernel/signal.c b/arch/arm/kernel/signal.c index 54cdf1aeefc3..ef2f86a5e78a 100644 --- a/arch/arm/kernel/signal.c +++ b/arch/arm/kernel/signal.c @@ -26,8 +26,8 @@ /* * For ARM syscalls, we encode the syscall number into the instruction. */ -#define SWI_SYS_SIGRETURN (0xef000000|(__NR_sigreturn)) -#define SWI_SYS_RT_SIGRETURN (0xef000000|(__NR_rt_sigreturn)) +#define SWI_SYS_SIGRETURN (0xef000000|(__NR_sigreturn)|(__NR_OABI_SYSCALL_BASE)) +#define SWI_SYS_RT_SIGRETURN (0xef000000|(__NR_rt_sigreturn)|(__NR_OABI_SYSCALL_BASE)) /* * With EABI, the syscall number has to be loaded into r7. diff --git a/arch/arm/kernel/sys_oabi-compat.c b/arch/arm/kernel/sys_oabi-compat.c index e8b98046895b..96ab5f52949c 100644 --- a/arch/arm/kernel/sys_oabi-compat.c +++ b/arch/arm/kernel/sys_oabi-compat.c @@ -25,6 +25,7 @@ * sys_stat64: * sys_lstat64: * sys_fstat64: + * sys_fstatat64: * * struct stat64 has different sizes and some members are shifted * Compatibility wrappers are needed for them and provided below. @@ -169,6 +170,29 @@ asmlinkage long sys_oabi_fstat64(unsigned long fd, return error; } +asmlinkage long sys_oabi_fstatat64(int dfd, + char __user *filename, + struct oldabi_stat64 __user *statbuf, + int flag) +{ + struct kstat stat; + int error = -EINVAL; + + if ((flag & ~AT_SYMLINK_NOFOLLOW) != 0) + goto out; + + if (flag & AT_SYMLINK_NOFOLLOW) + error = vfs_lstat_fd(dfd, filename, &stat); + else + error = vfs_stat_fd(dfd, filename, &stat); + + if (!error) + error = cp_oldabi_stat64(&stat, statbuf); + +out: + return error; +} + struct oabi_flock64 { short l_type; short l_whence; diff --git a/arch/arm/kernel/thumbee.c b/arch/arm/kernel/thumbee.c new file mode 100644 index 000000000000..df3f6b7ebcea --- /dev/null +++ b/arch/arm/kernel/thumbee.c @@ -0,0 +1,81 @@ +/* + * arch/arm/kernel/thumbee.c + * + * Copyright (C) 2008 ARM Limited + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +#include <linux/kernel.h> +#include <linux/init.h> + +#include <asm/thread_notify.h> + +/* + * Access to the ThumbEE Handler Base register + */ +static inline unsigned long teehbr_read() +{ + unsigned long v; + asm("mrc p14, 6, %0, c1, c0, 0\n" : "=r" (v)); + return v; +} + +static inline void teehbr_write(unsigned long v) +{ + asm("mcr p14, 6, %0, c1, c0, 0\n" : : "r" (v)); +} + +static int thumbee_notifier(struct notifier_block *self, unsigned long cmd, void *t) +{ + struct thread_info *thread = t; + + switch (cmd) { + case THREAD_NOTIFY_FLUSH: + thread->thumbee_state = 0; + break; + case THREAD_NOTIFY_SWITCH: + current_thread_info()->thumbee_state = teehbr_read(); + teehbr_write(thread->thumbee_state); + break; + } + + return NOTIFY_DONE; +} + +static struct notifier_block thumbee_notifier_block = { + .notifier_call = thumbee_notifier, +}; + +static int __init thumbee_init(void) +{ + unsigned long pfr0; + unsigned int cpu_arch = cpu_architecture(); + + if (cpu_arch < CPU_ARCH_ARMv7) + return 0; + + /* processor feature register 0 */ + asm("mrc p15, 0, %0, c0, c1, 0\n" : "=r" (pfr0)); + if ((pfr0 & 0x0000f000) != 0x00001000) + return 0; + + printk(KERN_INFO "ThumbEE CPU extension supported.\n"); + elf_hwcap |= HWCAP_THUMBEE; + thread_register_notifier(&thumbee_notifier_block); + + return 0; +} + +late_initcall(thumbee_init); |