diff options
| -rw-r--r-- | arch/arc/boot/.gitignore | 1 | ||||
| -rw-r--r-- | arch/arc/include/asm/cache.h | 2 | ||||
| -rw-r--r-- | arch/arc/include/asm/delay.h | 5 | ||||
| -rw-r--r-- | arch/arc/include/asm/entry.h | 24 | ||||
| -rw-r--r-- | arch/arc/include/asm/io.h | 4 | ||||
| -rw-r--r-- | arch/arc/include/asm/irqflags.h | 7 | ||||
| -rw-r--r-- | arch/arc/include/asm/mmu.h | 11 | ||||
| -rw-r--r-- | arch/arc/include/asm/mmu_context.h | 161 | ||||
| -rw-r--r-- | arch/arc/include/asm/pgtable.h | 61 | ||||
| -rw-r--r-- | arch/arc/include/asm/ptrace.h | 36 | ||||
| -rw-r--r-- | arch/arc/include/asm/spinlock_types.h | 6 | ||||
| -rw-r--r-- | arch/arc/kernel/.gitignore | 1 | ||||
| -rw-r--r-- | arch/arc/kernel/entry.S | 66 | ||||
| -rw-r--r-- | arch/arc/kernel/setup.c | 2 | ||||
| -rw-r--r-- | arch/arc/kernel/unaligned.c | 26 | ||||
| -rw-r--r-- | arch/arc/mm/cache_arc700.c | 8 | ||||
| -rw-r--r-- | arch/arc/mm/tlb.c | 174 | ||||
| -rw-r--r-- | arch/arc/mm/tlbex.S | 205 | ||||
| -rw-r--r-- | lib/Kconfig.debug | 6 |
19 files changed, 352 insertions, 454 deletions
diff --git a/arch/arc/boot/.gitignore b/arch/arc/boot/.gitignore new file mode 100644 index 000000000000..5d65b54bf17a --- /dev/null +++ b/arch/arc/boot/.gitignore @@ -0,0 +1 @@ +*.dtb* diff --git a/arch/arc/include/asm/cache.h b/arch/arc/include/asm/cache.h index 5802849a6cae..e4abdaac6f9f 100644 --- a/arch/arc/include/asm/cache.h +++ b/arch/arc/include/asm/cache.h @@ -57,7 +57,7 @@ extern void arc_cache_init(void); extern char *arc_cache_mumbojumbo(int cpu_id, char *buf, int len); -extern void __init read_decode_cache_bcr(void); +extern void read_decode_cache_bcr(void); #endif /* !__ASSEMBLY__ */ diff --git a/arch/arc/include/asm/delay.h b/arch/arc/include/asm/delay.h index 442ce5d0f709..43de30256981 100644 --- a/arch/arc/include/asm/delay.h +++ b/arch/arc/include/asm/delay.h @@ -53,11 +53,10 @@ static inline void __udelay(unsigned long usecs) { unsigned long loops; - /* (long long) cast ensures 64 bit MPY - real or emulated + /* (u64) cast ensures 64 bit MPY - real or emulated * HZ * 4295 is pre-evaluated by gcc - hence only 2 mpy ops */ - loops = ((long long)(usecs * 4295 * HZ) * - (long long)(loops_per_jiffy)) >> 32; + loops = ((u64) usecs * 4295 * HZ * loops_per_jiffy) >> 32; __delay(loops); } diff --git a/arch/arc/include/asm/entry.h b/arch/arc/include/asm/entry.h index df57611652e5..884081099f80 100644 --- a/arch/arc/include/asm/entry.h +++ b/arch/arc/include/asm/entry.h @@ -365,7 +365,7 @@ * it to memory (non-SMP case) or SCRATCH0 Aux Reg (SMP). * * Before saving the full regfile - this reg is restored back, only - * to be saved again on kernel mode stack, as part of ptregs. + * to be saved again on kernel mode stack, as part of pt_regs. *-------------------------------------------------------------*/ .macro EXCPN_PROLOG_FREEUP_REG reg #ifdef CONFIG_SMP @@ -384,6 +384,28 @@ .endm /*-------------------------------------------------------------- + * Exception Entry prologue + * -Switches stack to K mode (if not already) + * -Saves the register file + * + * After this it is safe to call the "C" handlers + *-------------------------------------------------------------*/ +.macro EXCEPTION_PROLOGUE + + /* Need at least 1 reg to code the early exception prologue */ + EXCPN_PROLOG_FREEUP_REG r9 + + /* U/K mode at time of exception (stack not switched if already K) */ + lr r9, [erstatus] + + /* ARC700 doesn't provide auto-stack switching */ + SWITCH_TO_KERNEL_STK + + /* save the regfile */ + SAVE_ALL_SYS +.endm + +/*-------------------------------------------------------------- * Save all registers used by Exceptions (TLB Miss, Prot-V, Mem err etc) * Requires SP to be already switched to kernel mode Stack * sp points to the next free element on the stack at exit of this macro. diff --git a/arch/arc/include/asm/io.h b/arch/arc/include/asm/io.h index 473424d7528b..334ce7017a18 100644 --- a/arch/arc/include/asm/io.h +++ b/arch/arc/include/asm/io.h @@ -100,6 +100,10 @@ static inline void __raw_writel(u32 w, volatile void __iomem *addr) } +#define readb_relaxed readb +#define readw_relaxed readw +#define readl_relaxed readl + #include <asm-generic/io.h> #endif /* _ASM_ARC_IO_H */ diff --git a/arch/arc/include/asm/irqflags.h b/arch/arc/include/asm/irqflags.h index d99f79bcf865..b68b53f458d1 100644 --- a/arch/arc/include/asm/irqflags.h +++ b/arch/arc/include/asm/irqflags.h @@ -157,13 +157,6 @@ static inline void arch_unmask_irq(unsigned int irq) flag \scratch .endm -.macro IRQ_DISABLE_SAVE scratch, save - lr \scratch, [status32] - mov \save, \scratch /* Make a copy */ - bic \scratch, \scratch, (STATUS_E1_MASK | STATUS_E2_MASK) - flag \scratch -.endm - .macro IRQ_ENABLE scratch lr \scratch, [status32] or \scratch, \scratch, (STATUS_E1_MASK | STATUS_E2_MASK) diff --git a/arch/arc/include/asm/mmu.h b/arch/arc/include/asm/mmu.h index 7c03fe61759c..c2663b32866b 100644 --- a/arch/arc/include/asm/mmu.h +++ b/arch/arc/include/asm/mmu.h @@ -32,6 +32,8 @@ /* Error code if probe fails */ #define TLB_LKUP_ERR 0x80000000 +#define TLB_DUP_ERR (TLB_LKUP_ERR | 0x00000001) + /* TLB Commands */ #define TLBWrite 0x1 #define TLBRead 0x2 @@ -46,21 +48,18 @@ #ifndef __ASSEMBLY__ typedef struct { - unsigned long asid; /* Pvt Addr-Space ID for mm */ -#ifdef CONFIG_ARC_TLB_DBG - struct task_struct *tsk; -#endif + unsigned long asid; /* 8 bit MMU PID + Generation cycle */ } mm_context_t; #ifdef CONFIG_ARC_DBG_TLB_PARANOIA -void tlb_paranoid_check(unsigned int pid_sw, unsigned long address); +void tlb_paranoid_check(unsigned int mm_asid, unsigned long address); #else #define tlb_paranoid_check(a, b) #endif void arc_mmu_init(void); extern char *arc_mmu_mumbojumbo(int cpu_id, char *buf, int len); -void __init read_decode_mmu_bcr(void); +void read_decode_mmu_bcr(void); #endif /* !__ASSEMBLY__ */ diff --git a/arch/arc/include/asm/mmu_context.h b/arch/arc/include/asm/mmu_context.h index 0d71fb11b57c..43a1b51bb8cc 100644 --- a/arch/arc/include/asm/mmu_context.h +++ b/arch/arc/include/asm/mmu_context.h @@ -34,95 +34,65 @@ * When it reaches max 255, the allocation cycle starts afresh by flushing * the entire TLB and wrapping ASID back to zero. * - * For book-keeping, Linux uses a couple of data-structures: - * -mm_struct has an @asid field to keep a note of task's ASID (needed at the - * time of say switch_mm( ) - * -An array of mm structs @asid_mm_map[] for asid->mm the reverse mapping, - * given an ASID, finding the mm struct associated. - * - * The round-robin allocation algorithm allows for ASID stealing. - * If asid tracker is at "x-1", a new req will allocate "x", even if "x" was - * already assigned to another (switched-out) task. Obviously the prev owner - * is marked with an invalid ASID to make it request for a new ASID when it - * gets scheduled next time. However its TLB entries (with ASID "x") could - * exist, which must be cleared before the same ASID is used by the new owner. - * Flushing them would be plausible but costly solution. Instead we force a - * allocation policy quirk, which ensures that a stolen ASID won't have any - * TLB entries associates, alleviating the need to flush. - * The quirk essentially is not allowing ASID allocated in prev cycle - * to be used past a roll-over in the next cycle. - * When this happens (i.e. task ASID > asid tracker), task needs to refresh - * its ASID, aligning it to current value of tracker. If the task doesn't get - * scheduled past a roll-over, hence its ASID is not yet realigned with - * tracker, such ASID is anyways safely reusable because it is - * gauranteed that TLB entries with that ASID wont exist. + * A new allocation cycle, post rollover, could potentially reassign an ASID + * to a different task. Thus the rule is to refresh the ASID in a new cycle. + * The 32 bit @asid_cache (and mm->asid) have 8 bits MMU PID and rest 24 bits + * serve as cycle/generation indicator and natural 32 bit unsigned math + * automagically increments the generation when lower 8 bits rollover. */ -#define FIRST_ASID 0 -#define MAX_ASID 255 /* 8 bit PID field in PID Aux reg */ -#define NO_ASID (MAX_ASID + 1) /* ASID Not alloc to mmu ctxt */ -#define NUM_ASID ((MAX_ASID - FIRST_ASID) + 1) +#define MM_CTXT_ASID_MASK 0x000000ff /* MMU PID reg :8 bit PID */ +#define MM_CTXT_CYCLE_MASK (~MM_CTXT_ASID_MASK) + +#define MM_CTXT_FIRST_CYCLE (MM_CTXT_ASID_MASK + 1) +#define MM_CTXT_NO_ASID 0UL -/* ASID to mm struct mapping */ -extern struct mm_struct *asid_mm_map[NUM_ASID + 1]; +#define hw_pid(mm) (mm->context.asid & MM_CTXT_ASID_MASK) -extern int asid_cache; +extern unsigned int asid_cache; /* - * Assign a new ASID to task. If the task already has an ASID, it is - * relinquished. + * Get a new ASID if task doesn't have a valid one (unalloc or from prev cycle) + * Also set the MMU PID register to existing/updated ASID */ static inline void get_new_mmu_context(struct mm_struct *mm) { - struct mm_struct *prev_owner; unsigned long flags; local_irq_save(flags); /* - * Relinquish the currently owned ASID (if any). - * Doing unconditionally saves a cmp-n-branch; for already unused - * ASID slot, the value was/remains NULL + * Move to new ASID if it was not from current alloc-cycle/generation. + * This is done by ensuring that the generation bits in both mm->ASID + * and cpu's ASID counter are exactly same. + * + * Note: Callers needing new ASID unconditionally, independent of + * generation, e.g. local_flush_tlb_mm() for forking parent, + * first need to destroy the context, setting it to invalid + * value. */ - asid_mm_map[mm->context.asid] = (struct mm_struct *)NULL; + if (!((mm->context.asid ^ asid_cache) & MM_CTXT_CYCLE_MASK)) + goto set_hw; + + /* move to new ASID and handle rollover */ + if (unlikely(!(++asid_cache & MM_CTXT_ASID_MASK))) { - /* move to new ASID */ - if (++asid_cache > MAX_ASID) { /* ASID roll-over */ - asid_cache = FIRST_ASID; flush_tlb_all(); - } - /* - * Is next ASID already owned by some-one else (we are stealing it). - * If so, let the orig owner be aware of this, so when it runs, it - * asks for a brand new ASID. This would only happen for a long-lived - * task with ASID from prev allocation cycle (before ASID roll-over). - * - * This might look wrong - if we are re-using some other task's ASID, - * won't we use it's stale TLB entries too. Actually switch_mm( ) takes - * care of such a case: it ensures that task with ASID from prev alloc - * cycle, when scheduled will refresh it's ASID: see switch_mm( ) below - * The stealing scenario described here will only happen if that task - * didn't get a chance to refresh it's ASID - implying stale entries - * won't exist. - */ - prev_owner = asid_mm_map[asid_cache]; - if (prev_owner) - prev_owner->context.asid = NO_ASID; + /* + * Above checke for rollover of 8 bit ASID in 32 bit container. + * If the container itself wrapped around, set it to a non zero + * "generation" to distinguish from no context + */ + if (!asid_cache) + asid_cache = MM_CTXT_FIRST_CYCLE; + } /* Assign new ASID to tsk */ - asid_mm_map[asid_cache] = mm; mm->context.asid = asid_cache; -#ifdef CONFIG_ARC_TLB_DBG - pr_info("ARC_TLB_DBG: NewMM=0x%x OldMM=0x%x task_struct=0x%x Task: %s," - " pid:%u, assigned asid:%lu\n", - (unsigned int)mm, (unsigned int)prev_owner, - (unsigned int)(mm->context.tsk), (mm->context.tsk)->comm, - (mm->context.tsk)->pid, mm->context.asid); -#endif - - write_aux_reg(ARC_REG_PID, asid_cache | MMU_ENABLE); +set_hw: + write_aux_reg(ARC_REG_PID, hw_pid(mm) | MMU_ENABLE); local_irq_restore(flags); } @@ -134,10 +104,7 @@ static inline void get_new_mmu_context(struct mm_struct *mm) static inline int init_new_context(struct task_struct *tsk, struct mm_struct *mm) { - mm->context.asid = NO_ASID; -#ifdef CONFIG_ARC_TLB_DBG - mm->context.tsk = tsk; -#endif + mm->context.asid = MM_CTXT_NO_ASID; return 0; } @@ -152,40 +119,21 @@ static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next, write_aux_reg(ARC_REG_SCRATCH_DATA0, next->pgd); #endif - /* - * Get a new ASID if task doesn't have a valid one. Possible when - * -task never had an ASID (fresh after fork) - * -it's ASID was stolen - past an ASID roll-over. - * -There's a third obscure scenario (if this task is running for the - * first time afer an ASID rollover), where despite having a valid - * ASID, we force a get for new ASID - see comments at top. - * - * Both the non-alloc scenario and first-use-after-rollover can be - * detected using the single condition below: NO_ASID = 256 - * while asid_cache is always a valid ASID value (0-255). - */ - if (next->context.asid > asid_cache) { - get_new_mmu_context(next); - } else { - /* - * XXX: This will never happen given the chks above - * BUG_ON(next->context.asid > MAX_ASID); - */ - write_aux_reg(ARC_REG_PID, next->context.asid | MMU_ENABLE); - } - + get_new_mmu_context(next); } +/* + * Called at the time of execve() to get a new ASID + * Note the subtlety here: get_new_mmu_context() behaves differently here + * vs. in switch_mm(). Here it always returns a new ASID, because mm has + * an unallocated "initial" value, while in latter, it moves to a new ASID, + * only if it was unallocated + */ +#define activate_mm(prev, next) switch_mm(prev, next, NULL) + static inline void destroy_context(struct mm_struct *mm) { - unsigned long flags; - - local_irq_save(flags); - - asid_mm_map[mm->context.asid] = NULL; - mm->context.asid = NO_ASID; - - local_irq_restore(flags); + mm->context.asid = MM_CTXT_NO_ASID; } /* it seemed that deactivate_mm( ) is a reasonable place to do book-keeping @@ -197,17 +145,6 @@ static inline void destroy_context(struct mm_struct *mm) */ #define deactivate_mm(tsk, mm) do { } while (0) -static inline void activate_mm(struct mm_struct *prev, struct mm_struct *next) -{ -#ifndef CONFIG_SMP - write_aux_reg(ARC_REG_SCRATCH_DATA0, next->pgd); -#endif - - /* Unconditionally get a new ASID */ - get_new_mmu_context(next); - -} - #define enter_lazy_tlb(mm, tsk) #endif /* __ASM_ARC_MMU_CONTEXT_H */ diff --git a/arch/arc/include/asm/pgtable.h b/arch/arc/include/asm/pgtable.h index 4749a0eee1cf..6b0b7f7ef783 100644 --- a/arch/arc/include/asm/pgtable.h +++ b/arch/arc/include/asm/pgtable.h @@ -57,43 +57,31 @@ #define _PAGE_ACCESSED (1<<1) /* Page is accessed (S) */ #define _PAGE_CACHEABLE (1<<2) /* Page is cached (H) */ -#define _PAGE_U_EXECUTE (1<<3) /* Page has user execute perm (H) */ -#define _PAGE_U_WRITE (1<<4) /* Page has user write perm (H) */ -#define _PAGE_U_READ (1<<5) /* Page has user read perm (H) */ -#define _PAGE_K_EXECUTE (1<<6) /* Page has kernel execute perm (H) */ -#define _PAGE_K_WRITE (1<<7) /* Page has kernel write perm (H) */ -#define _PAGE_K_READ (1<<8) /* Page has kernel perm (H) */ -#define _PAGE_GLOBAL (1<<9) /* Page is global (H) */ -#define _PAGE_MODIFIED (1<<10) /* Page modified (dirty) (S) */ -#define _PAGE_FILE (1<<10) /* page cache/ swap (S) */ -#define _PAGE_PRESENT (1<<11) /* TLB entry is valid (H) */ +#define _PAGE_EXECUTE (1<<3) /* Page has user execute perm (H) */ +#define _PAGE_WRITE (1<<4) /* Page has user write perm (H) */ +#define _PAGE_READ (1<<5) /* Page has user read perm (H) */ +#define _PAGE_MODIFIED (1<<6) /* Page modified (dirty) (S) */ +#define _PAGE_FILE (1<<7) /* page cache/ swap (S) */ +#define _PAGE_GLOBAL (1<<8) /* Page is global (H) */ +#define _PAGE_PRESENT (1<<10) /* TLB entry is valid (H) */ -#else +#else /* MMU v3 onwards */ -/* PD1 */ #define _PAGE_CACHEABLE (1<<0) /* Page is cached (H) */ -#define _PAGE_U_EXECUTE (1<<1) /* Page has user execute perm (H) */ -#define _PAGE_U_WRITE (1<<2) /* Page has user write perm (H) */ -#define _PAGE_U_READ (1<<3) /* Page has user read perm (H) */ -#define _PAGE_K_EXECUTE (1<<4) /* Page has kernel execute perm (H) */ -#define _PAGE_K_WRITE (1<<5) /* Page has kernel write perm (H) */ -#define _PAGE_K_READ (1<<6) /* Page has kernel perm (H) */ -#define _PAGE_ACCESSED (1<<7) /* Page is accessed (S) */ - -/* PD0 */ +#define _PAGE_EXECUTE (1<<1) /* Page has user execute perm (H) */ +#define _PAGE_WRITE (1<<2) /* Page has user write perm (H) */ +#define _PAGE_READ (1<<3) /* Page has user read perm (H) */ +#define _PAGE_ACCESSED (1<<4) /* Page is accessed (S) */ +#define _PAGE_MODIFIED (1<<5) /* Page modified (dirty) (S) */ +#define _PAGE_FILE (1<<6) /* page cache/ swap (S) */ #define _PAGE_GLOBAL (1<<8) /* Page is global (H) */ #define _PAGE_PRESENT (1<<9) /* TLB entry is valid (H) */ -#define _PAGE_SHARED_CODE (1<<10) /* Shared Code page with cmn vaddr +#define _PAGE_SHARED_CODE (1<<11) /* Shared Code page with cmn vaddr usable for shared TLB entries (H) */ - -#define _PAGE_MODIFIED (1<<11) /* Page modified (dirty) (S) */ -#define _PAGE_FILE (1<<12) /* page cache/ swap (S) */ - -#define _PAGE_SHARED_CODE_H (1<<31) /* Hardware counterpart of above */ #endif -/* Kernel allowed all permissions for all pages */ -#define _K_PAGE_PERMS (_PAGE_K_EXECUTE | _PAGE_K_WRITE | _PAGE_K_READ | \ +/* vmalloc permissions */ +#define _K_PAGE_PERMS (_PAGE_EXECUTE | _PAGE_WRITE | _PAGE_READ | \ _PAGE_GLOBAL | _PAGE_PRESENT) #ifdef CONFIG_ARC_CACHE_PAGES @@ -109,10 +97,6 @@ */ #define ___DEF (_PAGE_PRESENT | _PAGE_DEF_CACHEABLE) -#define _PAGE_READ (_PAGE_U_READ | _PAGE_K_READ) -#define _PAGE_WRITE (_PAGE_U_WRITE | _PAGE_K_WRITE) -#define _PAGE_EXECUTE (_PAGE_U_EXECUTE | _PAGE_K_EXECUTE) - /* Set of bits not changed in pte_modify */ #define _PAGE_CHG_MASK (PAGE_MASK | _PAGE_ACCESSED | _PAGE_MODIFIED) @@ -126,8 +110,8 @@ #define PAGE_SHARED PAGE_U_W_R -/* While kernel runs out of unstrslated space, vmalloc/modules use a chunk of - * kernel vaddr space - visible in all addr spaces, but kernel mode only +/* While kernel runs out of unstranslated space, vmalloc/modules use a chunk of + * user vaddr space - visible in all addr spaces, but kernel mode only * Thus Global, all-kernel-access, no-user-access, cached */ #define PAGE_KERNEL __pgprot(_K_PAGE_PERMS | _PAGE_DEF_CACHEABLE) @@ -136,10 +120,9 @@ #define PAGE_KERNEL_NO_CACHE __pgprot(_K_PAGE_PERMS) /* Masks for actual TLB "PD"s */ -#define PTE_BITS_IN_PD0 (_PAGE_GLOBAL | _PAGE_PRESENT) -#define PTE_BITS_IN_PD1 (PAGE_MASK | _PAGE_CACHEABLE | \ - _PAGE_U_EXECUTE | _PAGE_U_WRITE | _PAGE_U_READ | \ - _PAGE_K_EXECUTE | _PAGE_K_WRITE | _PAGE_K_READ) +#define PTE_BITS_IN_PD0 (_PAGE_GLOBAL | _PAGE_PRESENT) +#define PTE_BITS_RWX (_PAGE_EXECUTE | _PAGE_WRITE | _PAGE_READ) +#define PTE_BITS_NON_RWX_IN_PD1 (PAGE_MASK | _PAGE_CACHEABLE) /************************************************************************** * Mapping of vm_flags (Generic VM) to PTE flags (arch specific) diff --git a/arch/arc/include/asm/ptrace.h b/arch/arc/include/asm/ptrace.h index c9938e7a7dbd..1bfeec2c0558 100644 --- a/arch/arc/include/asm/ptrace.h +++ b/arch/arc/include/asm/ptrace.h @@ -20,27 +20,17 @@ struct pt_regs { /* Real registers */ long bta; /* bta_l1, bta_l2, erbta */ - long lp_start; - long lp_end; - long lp_count; + + long lp_start, lp_end, lp_count; + long status32; /* status32_l1, status32_l2, erstatus */ long ret; /* ilink1, ilink2 or eret */ long blink; long fp; long r26; /* gp */ - long r12; - long r11; - long r10; - long r9; - long r8; - long r7; - long r6; - long r5; - long r4; - long r3; - long r2; - long r1; - long r0; + + long r12, r11, r10, r9, r8, r7, r6, r5, r4, r3, r2, r1, r0; + long sp; /* user/kernel sp depending on where we came from */ long orig_r0; @@ -70,19 +60,7 @@ struct pt_regs { /* Callee saved registers - need to be saved only when you are scheduled out */ struct callee_regs { - long r25; - long r24; - long r23; - long r22; - long r21; - long r20; - long r19; - long r18; - long r17; - long r16; - long r15; - long r14; - long r13; + long r25, r24, r23, r22, r21, r20, r19, r18, r17, r16, r15, r14, r13; }; #define instruction_pointer(regs) ((regs)->ret) diff --git a/arch/arc/include/asm/spinlock_types.h b/arch/arc/include/asm/spinlock_types.h index 8276bfd61704..662627ced4f2 100644 --- a/arch/arc/include/asm/spinlock_types.h +++ b/arch/arc/include/asm/spinlock_types.h @@ -20,9 +20,9 @@ typedef struct { #define __ARCH_SPIN_LOCK_LOCKED { __ARCH_SPIN_LOCK_LOCKED__ } /* - * Unlocked: 0x01_00_00_00 - * Read lock(s): 0x00_FF_00_00 to say 0x01 - * Write lock: 0x0, but only possible if prior value "unlocked" 0x0100_0000 + * Unlocked : 0x0100_0000 + * Read lock(s) : 0x00FF_FFFF to 0x01 (Multiple Readers decrement it) + * Write lock : 0x0, but only if prior value is "unlocked" 0x0100_0000 */ typedef struct { volatile unsigned int counter; diff --git a/arch/arc/kernel/.gitignore b/arch/arc/kernel/.gitignore new file mode 100644 index 000000000000..c5f676c3c224 --- /dev/null +++ b/arch/arc/kernel/.gitignore @@ -0,0 +1 @@ +vmlinux.lds diff --git a/arch/arc/kernel/entry.S b/arch/arc/kernel/entry.S index 1d7165156e17..b908dde8a331 100644 --- a/arch/arc/kernel/entry.S +++ b/arch/arc/kernel/entry.S @@ -267,12 +267,7 @@ ARC_EXIT handle_interrupt_level1 ARC_ENTRY instr_service - EXCPN_PROLOG_FREEUP_REG r9 - - lr r9, [erstatus] - - SWITCH_TO_KERNEL_STK - SAVE_ALL_SYS + EXCEPTION_PROLOGUE lr r0, [efa] mov r1, sp @@ -289,15 +284,13 @@ ARC_EXIT instr_service ARC_ENTRY mem_service - EXCPN_PROLOG_FREEUP_REG r9 - - lr r9, [erstatus] - - SWITCH_TO_KERNEL_STK - SAVE_ALL_SYS + EXCEPTION_PROLOGUE lr r0, [efa] mov r1, sp + + FAKE_RET_FROM_EXCPN r9 + bl do_memory_error b ret_from_exception ARC_EXIT mem_service @@ -308,11 +301,7 @@ ARC_EXIT mem_service ARC_ENTRY EV_MachineCheck - EXCPN_PROLOG_FREEUP_REG r9 - lr r9, [erstatus] - - SWITCH_TO_KERNEL_STK - SAVE_ALL_SYS + EXCEPTION_PROLOGUE lr r2, [ecr] lr r0, [efa] @@ -342,13 +331,7 @@ ARC_EXIT EV_MachineCheck ARC_ENTRY EV_TLBProtV - EXCPN_PROLOG_FREEUP_REG r9 - - ;Which mode (user/kernel) was the system in when Exception occured - lr r9, [erstatus] - - SWITCH_TO_KERNEL_STK - SAVE_ALL_SYS + EXCEPTION_PROLOGUE ;---------(3) Save some more regs----------------- ; vineetg: Mar 6th: Random Seg Fault issue #1 @@ -406,12 +389,7 @@ ARC_EXIT EV_TLBProtV ; --------------------------------------------- ARC_ENTRY EV_PrivilegeV - EXCPN_PROLOG_FREEUP_REG r9 - - lr r9, [erstatus] - - SWITCH_TO_KERNEL_STK - SAVE_ALL_SYS + EXCEPTION_PROLOGUE lr r0, [efa] mov r1, sp @@ -427,14 +405,13 @@ ARC_EXIT EV_PrivilegeV ; --------------------------------------------- ARC_ENTRY EV_Extension - EXCPN_PROLOG_FREEUP_REG r9 - lr r9, [erstatus] - - SWITCH_TO_KERNEL_STK - SAVE_ALL_SYS + EXCEPTION_PROLOGUE lr r0, [efa] mov r1, sp + + FAKE_RET_FROM_EXCPN r9 + bl do_extension_fault b ret_from_exception ARC_EXIT EV_Extension @@ -526,14 +503,7 @@ trap_with_param: ARC_ENTRY EV_Trap - ; Need at least 1 reg to code the early exception prolog - EXCPN_PROLOG_FREEUP_REG r9 - - ;Which mode (user/kernel) was the system in when intr occured - lr r9, [erstatus] - - SWITCH_TO_KERNEL_STK - SAVE_ALL_SYS + EXCEPTION_PROLOGUE ;------- (4) What caused the Trap -------------- lr r12, [ecr] @@ -642,6 +612,9 @@ resume_kernel_mode: #ifdef CONFIG_PREEMPT + ; This is a must for preempt_schedule_irq() + IRQ_DISABLE r9 + ; Can't preempt if preemption disabled GET_CURR_THR_INFO_FROM_SP r10 ld r8, [r10, THREAD_INFO_PREEMPT_COUNT] @@ -651,8 +624,6 @@ resume_kernel_mode: ld r9, [r10, THREAD_INFO_FLAGS] bbit0 r9, TIF_NEED_RESCHED, restore_regs - IRQ_DISABLE r9 - ; Invoke PREEMPTION bl preempt_schedule_irq @@ -665,12 +636,11 @@ resume_kernel_mode: ; ; Restore the saved sys context (common exit-path for EXCPN/IRQ/Trap) ; IRQ shd definitely not happen between now and rtie +; All 2 entry points to here already disable interrupts restore_regs : - ; Disable Interrupts while restoring reg-file back - ; XXX can this be optimised out - IRQ_DISABLE_SAVE r9, r10 ;@r10 has prisitine (pre-disable) copy + lr r10, [status32] ; Restore REG File. In case multiple Events outstanding, ; use the same priorty as rtie: EXCPN, L2 IRQ, L1 IRQ, None diff --git a/arch/arc/kernel/setup.c b/arch/arc/kernel/setup.c index 6b083454d039..b011f8c164a1 100644 --- a/arch/arc/kernel/setup.c +++ b/arch/arc/kernel/setup.c @@ -357,8 +357,6 @@ void __init setup_arch(char **cmdline_p) */ root_mountflags &= ~MS_RDONLY; - console_verbose(); - #if defined(CONFIG_VT) && defined(CONFIG_DUMMY_CONSOLE) conswitchp = &dummy_con; #endif diff --git a/arch/arc/kernel/unaligned.c b/arch/arc/kernel/unaligned.c index c0f832f595d3..28d170060747 100644 --- a/arch/arc/kernel/unaligned.c +++ b/arch/arc/kernel/unaligned.c @@ -16,6 +16,16 @@ #include <linux/uaccess.h> #include <asm/disasm.h> +#ifdef CONFIG_CPU_BIG_ENDIAN +#define BE 1 +#define FIRST_BYTE_16 "swap %1, %1\n swape %1, %1\n" +#define FIRST_BYTE_32 "swape %1, %1\n" +#else +#define BE 0 +#define FIRST_BYTE_16 +#define FIRST_BYTE_32 +#endif + #define __get8_unaligned_check(val, addr, err) \ __asm__( \ "1: ldb.ab %1, [%2, 1]\n" \ @@ -36,9 +46,9 @@ do { \ unsigned int err = 0, v, a = addr; \ __get8_unaligned_check(v, a, err); \ - val = v ; \ + val = v << ((BE) ? 8 : 0); \ __get8_unaligned_check(v, a, err); \ - val |= v << 8; \ + val |= v << ((BE) ? 0 : 8); \ if (err) \ goto fault; \ } while (0) @@ -47,13 +57,13 @@ do { \ unsigned int err = 0, v, a = addr; \ __get8_unaligned_check(v, a, err); \ - val = v << 0; \ + val = v << ((BE) ? 24 : 0); \ __get8_unaligned_check(v, a, err); \ - val |= v << 8; \ + val |= v << ((BE) ? 16 : 8); \ __get8_unaligned_check(v, a, err); \ - val |= v << 16; \ + val |= v << ((BE) ? 8 : 16); \ __get8_unaligned_check(v, a, err); \ - val |= v << 24; \ + val |= v << ((BE) ? 0 : 24); \ if (err) \ goto fault; \ } while (0) @@ -63,6 +73,7 @@ unsigned int err = 0, v = val, a = addr;\ \ __asm__( \ + FIRST_BYTE_16 \ "1: stb.ab %1, [%2, 1]\n" \ " lsr %1, %1, 8\n" \ "2: stb %1, [%2]\n" \ @@ -87,8 +98,9 @@ #define put32_unaligned_check(val, addr) \ do { \ unsigned int err = 0, v = val, a = addr;\ - __asm__( \ \ + __asm__( \ + FIRST_BYTE_32 \ "1: stb.ab %1, [%2, 1]\n" \ " lsr %1, %1, 8\n" \ "2: stb.ab %1, [%2, 1]\n" \ diff --git a/arch/arc/mm/cache_arc700.c b/arch/arc/mm/cache_arc700.c index f415d851b765..5a1259cd948c 100644 --- a/arch/arc/mm/cache_arc700.c +++ b/arch/arc/mm/cache_arc700.c @@ -622,12 +622,12 @@ void flush_icache_range(unsigned long kstart, unsigned long kend) /* * General purpose helper to make I and D cache lines consistent. * @paddr is phy addr of region - * @vaddr is typically user or kernel vaddr (vmalloc) - * Howver in one instance, flush_icache_range() by kprobe (for a breakpt in + * @vaddr is typically user vaddr (breakpoint) or kernel vaddr (vmalloc) + * However in one instance, when called by kprobe (for a breakpt in * builtin kernel code) @vaddr will be paddr only, meaning CDU operation will * use a paddr to index the cache (despite VIPT). This is fine since since a - * built-in kernel page will not have any virtual mappings (not even kernel) - * kprobe on loadable module is different as it will have kvaddr. + * builtin kernel page will not have any virtual mappings. + * kprobe on loadable module will be kernel vaddr. */ void __sync_icache_dcache(unsigned long paddr, unsigned long vaddr, int len) { diff --git a/arch/arc/mm/tlb.c b/arch/arc/mm/tlb.c index 7957dc4e4d4a..71cb26df4255 100644 --- a/arch/arc/mm/tlb.c +++ b/arch/arc/mm/tlb.c @@ -52,6 +52,7 @@ */ #include <linux/module.h> +#include <linux/bug.h> #include <asm/arcregs.h> #include <asm/setup.h> #include <asm/mmu_context.h> @@ -99,48 +100,45 @@ /* A copy of the ASID from the PID reg is kept in asid_cache */ -int asid_cache = FIRST_ASID; - -/* ASID to mm struct mapping. We have one extra entry corresponding to - * NO_ASID to save us a compare when clearing the mm entry for old asid - * see get_new_mmu_context (asm-arc/mmu_context.h) - */ -struct mm_struct *asid_mm_map[NUM_ASID + 1]; +unsigned int asid_cache = MM_CTXT_FIRST_CYCLE; /* * Utility Routine to erase a J-TLB entry - * The procedure is to look it up in the MMU. If found, ERASE it by - * issuing a TlbWrite CMD with PD0 = PD1 = 0 + * Caller needs to setup Index Reg (manually or via getIndex) */ - -static void __tlb_entry_erase(void) +static inline void __tlb_entry_erase(void) { write_aux_reg(ARC_REG_TLBPD1, 0); write_aux_reg(ARC_REG_TLBPD0, 0); write_aux_reg(ARC_REG_TLBCOMMAND, TLBWrite); } -static void tlb_entry_erase(unsigned int vaddr_n_asid) +static inline unsigned int tlb_entry_lkup(unsigned long vaddr_n_asid) { unsigned int idx; - /* Locate the TLB entry for this vaddr + ASID */ write_aux_reg(ARC_REG_TLBPD0, vaddr_n_asid); + write_aux_reg(ARC_REG_TLBCOMMAND, TLBProbe); idx = read_aux_reg(ARC_REG_TLBINDEX); + return idx; +} + +static void tlb_entry_erase(unsigned int vaddr_n_asid) +{ + unsigned int idx; + + /* Locate the TLB entry for this vaddr + ASID */ + idx = tlb_entry_lkup(vaddr_n_asid); + /* No error means entry found, zero it out */ if (likely(!(idx & TLB_LKUP_ERR))) { __tlb_entry_erase(); - } else { /* Some sort of Error */ - + } else { /* Duplicate entry error */ - if (idx & 0x1) { - /* TODO we need to handle this case too */ - pr_emerg("unhandled Duplicate flush for %x\n", - vaddr_n_asid); - } - /* else entry not found so nothing to do */ + WARN(idx == TLB_DUP_ERR, "Probe returned Dup PD for %x\n", + vaddr_n_asid); } } @@ -159,7 +157,7 @@ static void utlb_invalidate(void) { #if (CONFIG_ARC_MMU_VER >= 2) -#if (CONFIG_ARC_MMU_VER < 3) +#if (CONFIG_ARC_MMU_VER == 2) /* MMU v2 introduced the uTLB Flush command. * There was however an obscure hardware bug, where uTLB flush would * fail when a prior probe for J-TLB (both totally unrelated) would @@ -182,6 +180,36 @@ static void utlb_invalidate(void) } +static void tlb_entry_insert(unsigned int pd0, unsigned int pd1) +{ + unsigned int idx; + + /* + * First verify if entry for this vaddr+ASID already exists + * This also sets up PD0 (vaddr, ASID..) for final commit + */ + idx = tlb_entry_lkup(pd0); + + /* + * If Not already present get a free slot from MMU. + * Otherwise, Probe would have located the entry and set INDEX Reg + * with existing location. This will cause Write CMD to over-write + * existing entry with new PD0 and PD1 + */ + if (likely(idx & TLB_LKUP_ERR)) + write_aux_reg(ARC_REG_TLBCOMMAND, TLBGetIndex); + + /* setup the other half of TLB entry (pfn, rwx..) */ + write_aux_reg(ARC_REG_TLBPD1, pd1); + + /* + * Commit the Entry to MMU + * It doesnt sound safe to use the TLBWriteNI cmd here + * which doesn't flush uTLBs. I'd rather be safe than sorry. + */ + write_aux_reg(ARC_REG_TLBCOMMAND, TLBWrite); +} + /* * Un-conditionally (without lookup) erase the entire MMU contents */ @@ -224,13 +252,14 @@ noinline void local_flush_tlb_mm(struct mm_struct *mm) return; /* - * Workaround for Android weirdism: - * A binder VMA could end up in a task such that vma->mm != tsk->mm - * old code would cause h/w - s/w ASID to get out of sync + * - Move to a new ASID, but only if the mm is still wired in + * (Android Binder ended up calling this for vma->mm != tsk->mm, + * causing h/w - s/w ASID to get out of sync) + * - Also get_new_mmu_context() new implementation allocates a new + * ASID only if it is not allocated already - so unallocate first */ - if (current->mm != mm) - destroy_context(mm); - else + destroy_context(mm); + if (current->mm == mm) get_new_mmu_context(mm); } @@ -246,7 +275,6 @@ void local_flush_tlb_range(struct vm_area_struct *vma, unsigned long start, unsigned long end) { unsigned long flags; - unsigned int asid; /* If range @start to @end is more than 32 TLB entries deep, * its better to move to a new ASID rather than searching for @@ -268,11 +296,10 @@ void local_flush_tlb_range(struct vm_area_struct *vma, unsigned long start, start &= PAGE_MASK; local_irq_save(flags); - asid = vma->vm_mm->context.asid; - if (asid != NO_ASID) { + if (vma->vm_mm->context.asid != MM_CTXT_NO_ASID) { while (start < end) { - tlb_entry_erase(start | (asid & 0xff)); + tlb_entry_erase(start | hw_pid(vma->vm_mm)); start += PAGE_SIZE; } } @@ -326,9 +353,8 @@ void local_flush_tlb_page(struct vm_area_struct *vma, unsigned long page) */ local_irq_save(flags); - if (vma->vm_mm->context.asid != NO_ASID) { - tlb_entry_erase((page & PAGE_MASK) | - (vma->vm_mm->context.asid & 0xff)); + if (vma->vm_mm->context.asid != MM_CTXT_NO_ASID) { + tlb_entry_erase((page & PAGE_MASK) | hw_pid(vma->vm_mm)); utlb_invalidate(); } @@ -341,8 +367,8 @@ void local_flush_tlb_page(struct vm_area_struct *vma, unsigned long page) void create_tlb(struct vm_area_struct *vma, unsigned long address, pte_t *ptep) { unsigned long flags; - unsigned int idx, asid_or_sasid; - unsigned long pd0_flags; + unsigned int asid_or_sasid, rwx; + unsigned long pd0, pd1; /* * create_tlb() assumes that current->mm == vma->mm, since @@ -381,40 +407,30 @@ void create_tlb(struct vm_area_struct *vma, unsigned long address, pte_t *ptep) /* update this PTE credentials */ pte_val(*ptep) |= (_PAGE_PRESENT | _PAGE_ACCESSED); - /* Create HW TLB entry Flags (in PD0) from PTE Flags */ -#if (CONFIG_ARC_MMU_VER <= 2) - pd0_flags = ((pte_val(*ptep) & PTE_BITS_IN_PD0) >> 1); -#else - pd0_flags = ((pte_val(*ptep) & PTE_BITS_IN_PD0)); -#endif + /* Create HW TLB(PD0,PD1) from PTE */ /* ASID for this task */ asid_or_sasid = read_aux_reg(ARC_REG_PID) & 0xff; - write_aux_reg(ARC_REG_TLBPD0, address | pd0_flags | asid_or_sasid); - - /* Load remaining info in PD1 (Page Frame Addr and Kx/Kw/Kr Flags) */ - write_aux_reg(ARC_REG_TLBPD1, (pte_val(*ptep) & PTE_BITS_IN_PD1)); - - /* First verify if entry for this vaddr+ASID already exists */ - write_aux_reg(ARC_REG_TLBCOMMAND, TLBProbe); - idx = read_aux_reg(ARC_REG_TLBINDEX); + pd0 = address | asid_or_sasid | (pte_val(*ptep) & PTE_BITS_IN_PD0); /* - * If Not already present get a free slot from MMU. - * Otherwise, Probe would have located the entry and set INDEX Reg - * with existing location. This will cause Write CMD to over-write - * existing entry with new PD0 and PD1 + * ARC MMU provides fully orthogonal access bits for K/U mode, + * however Linux only saves 1 set to save PTE real-estate + * Here we convert 3 PTE bits into 6 MMU bits: + * -Kernel only entries have Kr Kw Kx 0 0 0 + * -User entries have mirrored K and U bits */ - if (likely(idx & TLB_LKUP_ERR)) - write_aux_reg(ARC_REG_TLBCOMMAND, TLBGetIndex); + rwx = pte_val(*ptep) & PTE_BITS_RWX; - /* - * Commit the Entry to MMU - * It doesnt sound safe to use the TLBWriteNI cmd here - * which doesn't flush uTLBs. I'd rather be safe than sorry. - */ - write_aux_reg(ARC_REG_TLBCOMMAND, TLBWrite); + if (pte_val(*ptep) & _PAGE_GLOBAL) + rwx <<= 3; /* r w x => Kr Kw Kx 0 0 0 */ + else + rwx |= (rwx << 3); /* r w x => Kr Kw Kx Ur Uw Ux */ + + pd1 = rwx | (pte_val(*ptep) & PTE_BITS_NON_RWX_IN_PD1); + + tlb_entry_insert(pd0, pd1); local_irq_restore(flags); } @@ -553,13 +569,6 @@ void arc_mmu_init(void) if (mmu->pg_sz != PAGE_SIZE) panic("MMU pg size != PAGE_SIZE (%luk)\n", TO_KB(PAGE_SIZE)); - /* - * ASID mgmt data structures are compile time init - * asid_cache = FIRST_ASID and asid_mm_map[] all zeroes - */ - - local_flush_tlb_all(); - /* Enable the MMU */ write_aux_reg(ARC_REG_PID, MMU_ENABLE); @@ -671,25 +680,28 @@ void do_tlb_overlap_fault(unsigned long cause, unsigned long address, * Low Level ASM TLB handler calls this if it finds that HW and SW ASIDS * don't match */ -void print_asid_mismatch(int is_fast_path) +void print_asid_mismatch(int mm_asid, int mmu_asid, int is_fast_path) { - int pid_sw, pid_hw; - pid_sw = current->active_mm->context.asid; - pid_hw = read_aux_reg(ARC_REG_PID) & 0xff; - pr_emerg("ASID Mismatch in %s Path Handler: sw-pid=0x%x hw-pid=0x%x\n", - is_fast_path ? "Fast" : "Slow", pid_sw, pid_hw); + is_fast_path ? "Fast" : "Slow", mm_asid, mmu_asid); __asm__ __volatile__("flag 1"); } -void tlb_paranoid_check(unsigned int pid_sw, unsigned long addr) +void tlb_paranoid_check(unsigned int mm_asid, unsigned long addr) { - unsigned int pid_hw; + unsigned int mmu_asid; - pid_hw = read_aux_reg(ARC_REG_PID) & 0xff; + mmu_asid = read_aux_reg(ARC_REG_PID) & 0xff; - if (addr < 0x70000000 && ((pid_hw != pid_sw) || (pid_sw == NO_ASID))) - print_asid_mismatch(0); + /* + * At the time of a TLB miss/installation + * - HW version needs to match SW version + * - SW needs to have a valid ASID + */ + if (addr < 0x70000000 && + ((mm_asid == MM_CTXT_NO_ASID) || + (mmu_asid != (mm_asid & MM_CTXT_ASID_MASK)))) + print_asid_mismatch(mm_asid, mmu_asid, 0); } #endif diff --git a/arch/arc/mm/tlbex.S b/arch/arc/mm/tlbex.S index 5c5bb23001b0..cf7d7d9ad695 100644 --- a/arch/arc/mm/tlbex.S +++ b/arch/arc/mm/tlbex.S @@ -44,17 +44,36 @@ #include <asm/arcregs.h> #include <asm/cache.h> #include <asm/processor.h> -#if (CONFIG_ARC_MMU_VER == 1) #include <asm/tlb-mmu1.h> -#endif -;-------------------------------------------------------------------------- -; scratch memory to save the registers (r0-r3) used to code TLB refill Handler -; For details refer to comments before TLBMISS_FREEUP_REGS below +;----------------------------------------------------------------- +; ARC700 Exception Handling doesn't auto-switch stack and it only provides +; ONE scratch AUX reg "ARC_REG_SCRATCH_DATA0" +; +; For Non-SMP, the scratch AUX reg is repurposed to cache task PGD, so a +; "global" is used to free-up FIRST core reg to be able to code the rest of +; exception prologue (IRQ auto-disabled on Exceptions, so it's IRQ-safe). +; Since the Fast Path TLB Miss handler is coded with 4 regs, the remaining 3 +; need to be saved as well by extending the "global" to be 4 words. Hence +; ".size ex_saved_reg1, 16" +; [All of this dance is to avoid stack switching for each TLB Miss, since we +; only need to save only a handful of regs, as opposed to complete reg file] +; +; For ARC700 SMP, the "global" obviously can't be used for free up the FIRST +; core reg as it will not be SMP safe. +; Thus scratch AUX reg is used (and no longer used to cache task PGD). +; To save the rest of 3 regs - per cpu, the global is made "per-cpu". +; Epilogue thus has to locate the "per-cpu" storage for regs. +; To avoid cache line bouncing the per-cpu global is aligned/sized per +; L1_CACHE_SHIFT, despite fundamentally needing to be 12 bytes only. Hence +; ".size ex_saved_reg1, (CONFIG_NR_CPUS << L1_CACHE_SHIFT)" + +; As simple as that.... ;-------------------------------------------------------------------------- +; scratch memory to save [r0-r3] used to code TLB refill Handler ARCFP_DATA ex_saved_reg1 - .align 1 << L1_CACHE_SHIFT ; IMP: Must be Cache Line aligned + .align 1 << L1_CACHE_SHIFT .type ex_saved_reg1, @object #ifdef CONFIG_SMP .size ex_saved_reg1, (CONFIG_NR_CPUS << L1_CACHE_SHIFT) @@ -66,6 +85,44 @@ ex_saved_reg1: .zero 16 #endif +.macro TLBMISS_FREEUP_REGS +#ifdef CONFIG_SMP + sr r0, [ARC_REG_SCRATCH_DATA0] ; freeup r0 to code with + GET_CPU_ID r0 ; get to per cpu scratch mem, + lsl r0, r0, L1_CACHE_SHIFT ; cache line wide per cpu + add r0, @ex_saved_reg1, r0 +#else + st r0, [@ex_saved_reg1] + mov_s r0, @ex_saved_reg1 +#endif + st_s r1, [r0, 4] + st_s r2, [r0, 8] + st_s r3, [r0, 12] + + ; VERIFY if the ASID in MMU-PID Reg is same as + ; one in Linux data structures + + tlb_paranoid_check_asm +.endm + +.macro TLBMISS_RESTORE_REGS +#ifdef CONFIG_SMP + GET_CPU_ID r0 ; get to per cpu scratch mem + lsl r0, r0, L1_CACHE_SHIFT ; each is cache line wide + add r0, @ex_saved_reg1, r0 + ld_s r3, [r0,12] + ld_s r2, [r0, 8] + ld_s r1, [r0, 4] + lr r0, [ARC_REG_SCRATCH_DATA0] +#else + mov_s r0, @ex_saved_reg1 + ld_s r3, [r0,12] + ld_s r2, [r0, 8] + ld_s r1, [r0, 4] + ld_s r0, [r0] +#endif +.endm + ;============================================================================ ; Troubleshooting Stuff ;============================================================================ @@ -76,34 +133,35 @@ ex_saved_reg1: ; In bizzare scenrios SW and HW ASID can get out-of-sync which is trouble. ; So we try to detect this in TLB Mis shandler - -.macro DBG_ASID_MISMATCH +.macro tlb_paranoid_check_asm #ifdef CONFIG_ARC_DBG_TLB_PARANOIA - ; make sure h/w ASID is same as s/w ASID - GET_CURR_TASK_ON_CPU r3 ld r0, [r3, TASK_ACT_MM] ld r0, [r0, MM_CTXT+MM_CTXT_ASID] + breq r0, 0, 55f ; Error if no ASID allocated lr r1, [ARC_REG_PID] and r1, r1, 0xFF - breq r1, r0, 5f + and r2, r0, 0xFF ; MMU PID bits only for comparison + breq r1, r2, 5f + +55: ; Error if H/w and S/w ASID don't match, but NOT if in kernel mode - lr r0, [erstatus] - bbit0 r0, STATUS_U_BIT, 5f + lr r2, [erstatus] + bbit0 r2, STATUS_U_BIT, 5f ; We sure are in troubled waters, Flag the error, but to do so ; need to switch to kernel mode stack to call error routine GET_TSK_STACK_BASE r3, sp ; Call printk to shoutout aloud - mov r0, 1 + mov r2, 1 j print_asid_mismatch -5: ; ASIDs match so proceed normally +5: ; ASIDs match so proceed normally nop #endif @@ -161,13 +219,17 @@ ex_saved_reg1: ; IN: r0 = PTE, r1 = ptr to PTE .macro CONV_PTE_TO_TLB - and r3, r0, PTE_BITS_IN_PD1 ; Extract permission flags+PFN from PTE - sr r3, [ARC_REG_TLBPD1] ; these go in PD1 + and r3, r0, PTE_BITS_RWX ; r w x + lsl r2, r3, 3 ; r w x 0 0 0 + and.f 0, r0, _PAGE_GLOBAL + or.z r2, r2, r3 ; r w x r w x + + and r3, r0, PTE_BITS_NON_RWX_IN_PD1 ; Extract PFN+cache bits from PTE + or r3, r3, r2 + + sr r3, [ARC_REG_TLBPD1] ; these go in PD1 and r2, r0, PTE_BITS_IN_PD0 ; Extract other PTE flags: (V)alid, (G)lb -#if (CONFIG_ARC_MMU_VER <= 2) /* Neednot be done with v3 onwards */ - lsr r2, r2 ; shift PTE flags to match layout in PD0 -#endif lr r3,[ARC_REG_TLBPD0] ; MMU prepares PD0 with vaddr and asid @@ -191,68 +253,6 @@ ex_saved_reg1: #endif .endm -;----------------------------------------------------------------- -; ARC700 Exception Handling doesn't auto-switch stack and it only provides -; ONE scratch AUX reg "ARC_REG_SCRATCH_DATA0" -; -; For Non-SMP, the scratch AUX reg is repurposed to cache task PGD, so a -; "global" is used to free-up FIRST core reg to be able to code the rest of -; exception prologue (IRQ auto-disabled on Exceptions, so it's IRQ-safe). -; Since the Fast Path TLB Miss handler is coded with 4 regs, the remaining 3 -; need to be saved as well by extending the "global" to be 4 words. Hence -; ".size ex_saved_reg1, 16" -; [All of this dance is to avoid stack switching for each TLB Miss, since we -; only need to save only a handful of regs, as opposed to complete reg file] -; -; For ARC700 SMP, the "global" obviously can't be used for free up the FIRST -; core reg as it will not be SMP safe. -; Thus scratch AUX reg is used (and no longer used to cache task PGD). -; To save the rest of 3 regs - per cpu, the global is made "per-cpu". -; Epilogue thus has to locate the "per-cpu" storage for regs. -; To avoid cache line bouncing the per-cpu global is aligned/sized per -; L1_CACHE_SHIFT, despite fundamentally needing to be 12 bytes only. Hence -; ".size ex_saved_reg1, (CONFIG_NR_CPUS << L1_CACHE_SHIFT)" - -; As simple as that.... - -.macro TLBMISS_FREEUP_REGS -#ifdef CONFIG_SMP - sr r0, [ARC_REG_SCRATCH_DATA0] ; freeup r0 to code with - GET_CPU_ID r0 ; get to per cpu scratch mem, - lsl r0, r0, L1_CACHE_SHIFT ; cache line wide per cpu - add r0, @ex_saved_reg1, r0 -#else - st r0, [@ex_saved_reg1] - mov_s r0, @ex_saved_reg1 -#endif - st_s r1, [r0, 4] - st_s r2, [r0, 8] - st_s r3, [r0, 12] - - ; VERIFY if the ASID in MMU-PID Reg is same as - ; one in Linux data structures - - DBG_ASID_MISMATCH -.endm - -;----------------------------------------------------------------- -.macro TLBMISS_RESTORE_REGS -#ifdef CONFIG_SMP - GET_CPU_ID r0 ; get to per cpu scratch mem - lsl r0, r0, L1_CACHE_SHIFT ; each is cache line wide - add r0, @ex_saved_reg1, r0 - ld_s r3, [r0,12] - ld_s r2, [r0, 8] - ld_s r1, [r0, 4] - lr r0, [ARC_REG_SCRATCH_DATA0] -#else - mov_s r0, @ex_saved_reg1 - ld_s r3, [r0,12] - ld_s r2, [r0, 8] - ld_s r1, [r0, 4] - ld_s r0, [r0] -#endif -.endm ARCFP_CODE ;Fast Path Code, candidate for ICCM @@ -277,8 +277,8 @@ ARC_ENTRY EV_TLBMissI ;---------------------------------------------------------------- ; VERIFY_PTE: Check if PTE permissions approp for executing code cmp_s r2, VMALLOC_START - mov.lo r2, (_PAGE_PRESENT | _PAGE_U_EXECUTE) - mov.hs r2, (_PAGE_PRESENT | _PAGE_K_EXECUTE) + mov_s r2, (_PAGE_PRESENT | _PAGE_EXECUTE) + or.hs r2, r2, _PAGE_GLOBAL and r3, r0, r2 ; Mask out NON Flag bits from PTE xor.f r3, r3, r2 ; check ( ( pte & flags_test ) == flags_test ) @@ -317,26 +317,21 @@ ARC_ENTRY EV_TLBMissD ;---------------------------------------------------------------- ; VERIFY_PTE: Chk if PTE permissions approp for data access (R/W/R+W) - mov_s r2, 0 + cmp_s r2, VMALLOC_START + mov_s r2, _PAGE_PRESENT ; common bit for K/U PTE + or.hs r2, r2, _PAGE_GLOBAL ; kernel PTE only + + ; Linux PTE [RWX] bits are semantically overloaded: + ; -If PAGE_GLOBAL set, they refer to kernel-only flags (vmalloc) + ; -Otherwise they are user-mode permissions, and those are exactly + ; same for kernel mode as well (e.g. copy_(to|from)_user) + lr r3, [ecr] btst_s r3, ECR_C_BIT_DTLB_LD_MISS ; Read Access - or.nz r2, r2, _PAGE_U_READ ; chk for Read flag in PTE + or.nz r2, r2, _PAGE_READ ; chk for Read flag in PTE btst_s r3, ECR_C_BIT_DTLB_ST_MISS ; Write Access - or.nz r2, r2, _PAGE_U_WRITE ; chk for Write flag in PTE - ; Above laddering takes care of XCHG access - ; which is both Read and Write - - ; If kernel mode access, ; make _PAGE_xx flags as _PAGE_K_xx - ; For copy_(to|from)_user, despite exception taken in kernel mode, - ; this code is not hit, because EFA would still be the user mode - ; address (EFA < 0x6000_0000). - ; This code is for legit kernel mode faults, vmalloc specifically - ; (EFA: 0x7000_0000 to 0x7FFF_FFFF) - - lr r3, [efa] - cmp r3, VMALLOC_START - 1 ; If kernel mode access - asl.hi r2, r2, 3 ; make _PAGE_xx flags as _PAGE_K_xx - or r2, r2, _PAGE_PRESENT ; Common flag for K/U mode + or.nz r2, r2, _PAGE_WRITE ; chk for Write flag in PTE + ; Above laddering takes care of XCHG access (both R and W) ; By now, r2 setup with all the Flags we need to check in PTE and r3, r0, r2 ; Mask out NON Flag bits from PTE @@ -371,13 +366,7 @@ do_slow_path_pf: ; Slow path TLB Miss handled as a regular ARC Exception ; (stack switching / save the complete reg-file). - ; That requires freeing up r9 - EXCPN_PROLOG_FREEUP_REG r9 - - lr r9, [erstatus] - - SWITCH_TO_KERNEL_STK - SAVE_ALL_SYS + EXCEPTION_PROLOGUE ; ------- setup args for Linux Page fault Hanlder --------- mov_s r0, sp diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index 444e1c12fea9..652bea9054f0 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -908,7 +908,7 @@ config LOCKDEP bool depends on DEBUG_KERNEL && TRACE_IRQFLAGS_SUPPORT && STACKTRACE_SUPPORT && LOCKDEP_SUPPORT select STACKTRACE - select FRAME_POINTER if !MIPS && !PPC && !ARM_UNWIND && !S390 && !MICROBLAZE + select FRAME_POINTER if !MIPS && !PPC && !ARM_UNWIND && !S390 && !MICROBLAZE && !ARC select KALLSYMS select KALLSYMS_ALL @@ -1366,7 +1366,7 @@ config FAULT_INJECTION_STACKTRACE_FILTER depends on FAULT_INJECTION_DEBUG_FS && STACKTRACE_SUPPORT depends on !X86_64 select STACKTRACE - select FRAME_POINTER if !MIPS && !PPC && !S390 && !MICROBLAZE && !ARM_UNWIND + select FRAME_POINTER if !MIPS && !PPC && !S390 && !MICROBLAZE && !ARM_UNWIND && !ARC help Provide stacktrace filter for fault-injection capabilities @@ -1376,7 +1376,7 @@ config LATENCYTOP depends on DEBUG_KERNEL depends on STACKTRACE_SUPPORT depends on PROC_FS - select FRAME_POINTER if !MIPS && !PPC && !S390 && !MICROBLAZE && !ARM_UNWIND + select FRAME_POINTER if !MIPS && !PPC && !S390 && !MICROBLAZE && !ARM_UNWIND && !ARC select KALLSYMS select KALLSYMS_ALL select STACKTRACE |