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__ */
{
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);
}
* 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
#endif
.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
}
+#define readb_relaxed readb
+#define readw_relaxed readw
+#define readl_relaxed readl
+
#include <asm-generic/io.h>
#endif /* _ASM_ARC_IO_H */
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)
/* 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
#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__ */
* 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);
}
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;
}
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
*/
#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 */
#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
*/
#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)
#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)
#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)
/* 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;
/* 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)
#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;
--- /dev/null
+vmlinux.lds
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
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
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]
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
; ---------------------------------------------
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
; ---------------------------------------------
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
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]
#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]
ld r9, [r10, THREAD_INFO_FLAGS]
bbit0 r9, TIF_NEED_RESCHED, restore_regs
- IRQ_DISABLE r9
-
; Invoke PREEMPTION
bl preempt_schedule_irq
;
; 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
*/
root_mountflags &= ~MS_RDONLY;
- console_verbose();
-
#if defined(CONFIG_VT) && defined(CONFIG_DUMMY_CONSOLE)
conswitchp = &dummy_con;
#endif
#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" \
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)
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)
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" \
#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" \
/*
* 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)
{
*/
#include <linux/module.h>
+#include <linux/bug.h>
#include <asm/arcregs.h>
#include <asm/setup.h>
#include <asm/mmu_context.h>
/* 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);
}
}
{
#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
}
+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
*/
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);
}
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
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;
}
}
*/
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();
}
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
/* 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);
}
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);
* 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
#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)
.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
;============================================================================
; 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
; 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
#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
;----------------------------------------------------------------
; 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 )
;----------------------------------------------------------------
; 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
; 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
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
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
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
projects / ~andy / linux / commitdiff