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-rw-r--r--Documentation/fujitsu/frv/kernel-ABI.txt234
-rw-r--r--arch/frv/Makefile2
-rw-r--r--arch/frv/kernel/break.S77
-rw-r--r--arch/frv/kernel/entry-table.S39
-rw-r--r--arch/frv/kernel/entry.S65
-rw-r--r--arch/frv/kernel/head.S3
-rw-r--r--arch/frv/kernel/irq.c41
-rw-r--r--include/asm-frv/spr-regs.h1
-rw-r--r--include/asm-frv/system.h88
9 files changed, 489 insertions, 61 deletions
diff --git a/Documentation/fujitsu/frv/kernel-ABI.txt b/Documentation/fujitsu/frv/kernel-ABI.txt
new file mode 100644
index 0000000..0ed9b0a
--- /dev/null
+++ b/Documentation/fujitsu/frv/kernel-ABI.txt
@@ -0,0 +1,234 @@
+ =================================
+ INTERNAL KERNEL ABI FOR FR-V ARCH
+ =================================
+
+The internal FRV kernel ABI is not quite the same as the userspace ABI. A number of the registers
+are used for special purposed, and the ABI is not consistent between modules vs core, and MMU vs
+no-MMU.
+
+This partly stems from the fact that FRV CPUs do not have a separate supervisor stack pointer, and
+most of them do not have any scratch registers, thus requiring at least one general purpose
+register to be clobbered in such an event. Also, within the kernel core, it is possible to simply
+jump or call directly between functions using a relative offset. This cannot be extended to modules
+for the displacement is likely to be too far. Thus in modules the address of a function to call
+must be calculated in a register and then used, requiring two extra instructions.
+
+This document has the following sections:
+
+ (*) System call register ABI
+ (*) CPU operating modes
+ (*) Internal kernel-mode register ABI
+ (*) Internal debug-mode register ABI
+ (*) Virtual interrupt handling
+
+
+========================
+SYSTEM CALL REGISTER ABI
+========================
+
+When a system call is made, the following registers are effective:
+
+ REGISTERS CALL RETURN
+ =============== ======================= =======================
+ GR7 System call number Preserved
+ GR8 Syscall arg #1 Return value
+ GR9-GR13 Syscall arg #2-6 Preserved
+
+
+===================
+CPU OPERATING MODES
+===================
+
+The FR-V CPU has three basic operating modes. In order of increasing capability:
+
+ (1) User mode.
+
+ Basic userspace running mode.
+
+ (2) Kernel mode.
+
+ Normal kernel mode. There are many additional control registers available that may be
+ accessed in this mode, in addition to all the stuff available to user mode. This has two
+ submodes:
+
+ (a) Exceptions enabled (PSR.T == 1).
+
+ Exceptions will invoke the appropriate normal kernel mode handler. On entry to the
+ handler, the PSR.T bit will be cleared.
+
+ (b) Exceptions disabled (PSR.T == 0).
+
+ No exceptions or interrupts may happen. Any mandatory exceptions will cause the CPU to
+ halt unless the CPU is told to jump into debug mode instead.
+
+ (3) Debug mode.
+
+ No exceptions may happen in this mode. Memory protection and management exceptions will be
+ flagged for later consideration, but the exception handler won't be invoked. Debugging traps
+ such as hardware breakpoints and watchpoints will be ignored. This mode is entered only by
+ debugging events obtained from the other two modes.
+
+ All kernel mode registers may be accessed, plus a few extra debugging specific registers.
+
+
+=================================
+INTERNAL KERNEL-MODE REGISTER ABI
+=================================
+
+There are a number of permanent register assignments that are set up by entry.S in the exception
+prologue. Note that there is a complete set of exception prologues for each of user->kernel
+transition and kernel->kernel transition. There are also user->debug and kernel->debug mode
+transition prologues.
+
+
+ REGISTER FLAVOUR USE
+ =============== ======= ====================================================
+ GR1 Supervisor stack pointer
+ GR15 Current thread info pointer
+ GR16 GP-Rel base register for small data
+ GR28 Current exception frame pointer (__frame)
+ GR29 Current task pointer (current)
+ GR30 Destroyed by kernel mode entry
+ GR31 NOMMU Destroyed by debug mode entry
+ GR31 MMU Destroyed by TLB miss kernel mode entry
+ CCR.ICC2 Virtual interrupt disablement tracking
+ CCCR.CC3 Cleared by exception prologue (atomic op emulation)
+ SCR0 MMU See mmu-layout.txt.
+ SCR1 MMU See mmu-layout.txt.
+ SCR2 MMU Save for EAR0 (destroyed by icache insns in debug mode)
+ SCR3 MMU Save for GR31 during debug exceptions
+ DAMR/IAMR NOMMU Fixed memory protection layout.
+ DAMR/IAMR MMU See mmu-layout.txt.
+
+
+Certain registers are also used or modified across function calls:
+
+ REGISTER CALL RETURN
+ =============== =============================== ===============================
+ GR0 Fixed Zero -
+ GR2 Function call frame pointer
+ GR3 Special Preserved
+ GR3-GR7 - Clobbered
+ GR8 Function call arg #1 Return value (or clobbered)
+ GR9 Function call arg #2 Return value MSW (or clobbered)
+ GR10-GR13 Function call arg #3-#6 Clobbered
+ GR14 - Clobbered
+ GR15-GR16 Special Preserved
+ GR17-GR27 - Preserved
+ GR28-GR31 Special Only accessed explicitly
+ LR Return address after CALL Clobbered
+ CCR/CCCR - Mostly Clobbered
+
+
+================================
+INTERNAL DEBUG-MODE REGISTER ABI
+================================
+
+This is the same as the kernel-mode register ABI for functions calls. The difference is that in
+debug-mode there's a different stack and a different exception frame. Almost all the global
+registers from kernel-mode (including the stack pointer) may be changed.
+
+ REGISTER FLAVOUR USE
+ =============== ======= ====================================================
+ GR1 Debug stack pointer
+ GR16 GP-Rel base register for small data
+ GR31 Current debug exception frame pointer (__debug_frame)
+ SCR3 MMU Saved value of GR31
+
+
+Note that debug mode is able to interfere with the kernel's emulated atomic ops, so it must be
+exceedingly careful not to do any that would interact with the main kernel in this regard. Hence
+the debug mode code (gdbstub) is almost completely self-contained. The only external code used is
+the sprintf family of functions.
+
+Futhermore, break.S is so complicated because single-step mode does not switch off on entry to an
+exception. That means unless manually disabled, single-stepping will blithely go on stepping into
+things like interrupts. See gdbstub.txt for more information.
+
+
+==========================
+VIRTUAL INTERRUPT HANDLING
+==========================
+
+Because accesses to the PSR is so slow, and to disable interrupts we have to access it twice (once
+to read and once to write), we don't actually disable interrupts at all if we don't have to. What
+we do instead is use the ICC2 condition code flags to note virtual disablement, such that if we
+then do take an interrupt, we note the flag, really disable interrupts, set another flag and resume
+execution at the point the interrupt happened. Setting condition flags as a side effect of an
+arithmetic or logical instruction is really fast. This use of the ICC2 only occurs within the
+kernel - it does not affect userspace.
+
+The flags we use are:
+
+ (*) CCR.ICC2.Z [Zero flag]
+
+ Set to virtually disable interrupts, clear when interrupts are virtually enabled. Can be
+ modified by logical instructions without affecting the Carry flag.
+
+ (*) CCR.ICC2.C [Carry flag]
+
+ Clear to indicate hardware interrupts are really disabled, set otherwise.
+
+
+What happens is this:
+
+ (1) Normal kernel-mode operation.
+
+ ICC2.Z is 0, ICC2.C is 1.
+
+ (2) An interrupt occurs. The exception prologue examines ICC2.Z and determines that nothing needs
+ doing. This is done simply with an unlikely BEQ instruction.
+
+ (3) The interrupts are disabled (local_irq_disable)
+
+ ICC2.Z is set to 1.
+
+ (4) If interrupts were then re-enabled (local_irq_enable):
+
+ ICC2.Z would be set to 0.
+
+ A TIHI #2 instruction (trap #2 if condition HI - Z==0 && C==0) would be used to trap if
+ interrupts were now virtually enabled, but physically disabled - which they're not, so the
+ trap isn't taken. The kernel would then be back to state (1).
+
+ (5) An interrupt occurs. The exception prologue examines ICC2.Z and determines that the interrupt
+ shouldn't actually have happened. It jumps aside, and there disabled interrupts by setting
+ PSR.PIL to 14 and then it clears ICC2.C.
+
+ (6) If interrupts were then saved and disabled again (local_irq_save):
+
+ ICC2.Z would be shifted into the save variable and masked off (giving a 1).
+
+ ICC2.Z would then be set to 1 (thus unchanged), and ICC2.C would be unaffected (ie: 0).
+
+ (7) If interrupts were then restored from state (6) (local_irq_restore):
+
+ ICC2.Z would be set to indicate the result of XOR'ing the saved value (ie: 1) with 1, which
+ gives a result of 0 - thus leaving ICC2.Z set.
+
+ ICC2.C would remain unaffected (ie: 0).
+
+ A TIHI #2 instruction would be used to again assay the current state, but this would do
+ nothing as Z==1.
+
+ (8) If interrupts were then enabled (local_irq_enable):
+
+ ICC2.Z would be cleared. ICC2.C would be left unaffected. Both flags would now be 0.
+
+ A TIHI #2 instruction again issued to assay the current state would then trap as both Z==0
+ [interrupts virtually enabled] and C==0 [interrupts really disabled] would then be true.
+
+ (9) The trap #2 handler would simply enable hardware interrupts (set PSR.PIL to 0), set ICC2.C to
+ 1 and return.
+
+(10) Immediately upon returning, the pending interrupt would be taken.
+
+(11) The interrupt handler would take the path of actually processing the interrupt (ICC2.Z is
+ clear, BEQ fails as per step (2)).
+
+(12) The interrupt handler would then set ICC2.C to 1 since hardware interrupts are definitely
+ enabled - or else the kernel wouldn't be here.
+
+(13) On return from the interrupt handler, things would be back to state (1).
+
+This trap (#2) is only available in kernel mode. In user mode it will result in SIGILL.
diff --git a/arch/frv/Makefile b/arch/frv/Makefile
index 90c0fb8..d163747 100644
--- a/arch/frv/Makefile
+++ b/arch/frv/Makefile
@@ -81,7 +81,7 @@ endif
# - reserve CC3 for use with atomic ops
# - all the extra registers are dealt with only at context switch time
CFLAGS += -mno-fdpic -mgpr-32 -msoft-float -mno-media
-CFLAGS += -ffixed-fcc3 -ffixed-cc3 -ffixed-gr15
+CFLAGS += -ffixed-fcc3 -ffixed-cc3 -ffixed-gr15 -ffixed-icc2
AFLAGS += -mno-fdpic
ASFLAGS += -mno-fdpic
diff --git a/arch/frv/kernel/break.S b/arch/frv/kernel/break.S
index 33233dc..687c48d 100644
--- a/arch/frv/kernel/break.S
+++ b/arch/frv/kernel/break.S
@@ -200,12 +200,20 @@ __break_step:
movsg bpcsr,gr2
sethi.p %hi(__entry_kernel_external_interrupt),gr3
setlo %lo(__entry_kernel_external_interrupt),gr3
- subcc gr2,gr3,gr0,icc0
+ subcc.p gr2,gr3,gr0,icc0
+ sethi %hi(__entry_uspace_external_interrupt),gr3
+ setlo.p %lo(__entry_uspace_external_interrupt),gr3
beq icc0,#2,__break_step_kernel_external_interrupt
- sethi.p %hi(__entry_uspace_external_interrupt),gr3
- setlo %lo(__entry_uspace_external_interrupt),gr3
- subcc gr2,gr3,gr0,icc0
+ subcc.p gr2,gr3,gr0,icc0
+ sethi %hi(__entry_kernel_external_interrupt_virtually_disabled),gr3
+ setlo.p %lo(__entry_kernel_external_interrupt_virtually_disabled),gr3
beq icc0,#2,__break_step_uspace_external_interrupt
+ subcc.p gr2,gr3,gr0,icc0
+ sethi %hi(__entry_kernel_external_interrupt_virtual_reenable),gr3
+ setlo.p %lo(__entry_kernel_external_interrupt_virtual_reenable),gr3
+ beq icc0,#2,__break_step_kernel_external_interrupt_virtually_disabled
+ subcc gr2,gr3,gr0,icc0
+ beq icc0,#2,__break_step_kernel_external_interrupt_virtual_reenable
LEDS 0x2007,gr2
@@ -254,6 +262,9 @@ __break_step_kernel_softprog_interrupt:
# step through an external interrupt from kernel mode
.globl __break_step_kernel_external_interrupt
__break_step_kernel_external_interrupt:
+ # deal with virtual interrupt disablement
+ beq icc2,#0,__break_step_kernel_external_interrupt_virtually_disabled
+
sethi.p %hi(__entry_kernel_external_interrupt_reentry),gr3
setlo %lo(__entry_kernel_external_interrupt_reentry),gr3
@@ -294,6 +305,64 @@ __break_return_as_kernel_prologue:
#endif
rett #1
+# we single-stepped into an interrupt handler whilst interrupts were merely virtually disabled
+# need to really disable interrupts, set flag, fix up and return
+__break_step_kernel_external_interrupt_virtually_disabled:
+ movsg psr,gr2
+ andi gr2,#~PSR_PIL,gr2
+ ori gr2,#PSR_PIL_14,gr2 /* debugging interrupts only */
+ movgs gr2,psr
+
+ ldi @(gr31,#REG_CCR),gr3
+ movgs gr3,ccr
+ subcc.p gr0,gr0,gr0,icc2 /* leave Z set, clear C */
+
+ # exceptions must've been enabled and we must've been in supervisor mode
+ setlos BPSR_BET|BPSR_BS,gr3
+ movgs gr3,bpsr
+
+ # return to where the interrupt happened
+ movsg pcsr,gr2
+ movgs gr2,bpcsr
+
+ lddi.p @(gr31,#REG_GR(2)),gr2
+
+ xor gr31,gr31,gr31
+ movgs gr0,brr
+#ifdef CONFIG_MMU
+ movsg scr3,gr31
+#endif
+ rett #1
+
+# we stepped through into the virtual interrupt reenablement trap
+#
+# we also want to single step anyway, but after fixing up so that we get an event on the
+# instruction after the broken-into exception returns
+ .globl __break_step_kernel_external_interrupt_virtual_reenable
+__break_step_kernel_external_interrupt_virtual_reenable:
+ movsg psr,gr2
+ andi gr2,#~PSR_PIL,gr2
+ movgs gr2,psr
+
+ ldi @(gr31,#REG_CCR),gr3
+ movgs gr3,ccr
+ subicc gr0,#1,gr0,icc2 /* clear Z, set C */
+
+ # save the adjusted ICC2
+ movsg ccr,gr3
+ sti gr3,@(gr31,#REG_CCR)
+
+ # exceptions must've been enabled and we must've been in supervisor mode
+ setlos BPSR_BET|BPSR_BS,gr3
+ movgs gr3,bpsr
+
+ # return to where the trap happened
+ movsg pcsr,gr2
+ movgs gr2,bpcsr
+
+ # and then process the single step
+ bra __break_continue
+
# step through an internal exception from uspace mode
.globl __break_step_uspace_softprog_interrupt
__break_step_uspace_softprog_interrupt:
diff --git a/arch/frv/kernel/entry-table.S b/arch/frv/kernel/entry-table.S
index 9b9243e..81568ac 100644
--- a/arch/frv/kernel/entry-table.S
+++ b/arch/frv/kernel/entry-table.S
@@ -116,6 +116,8 @@ __break_kerneltrap_fixup_table:
.long __break_step_uspace_external_interrupt
.section .trap.kernel
.org \tbr_tt
+ # deal with virtual interrupt disablement
+ beq icc2,#0,__entry_kernel_external_interrupt_virtually_disabled
bra __entry_kernel_external_interrupt
.section .trap.fixup.kernel
.org \tbr_tt >> 2
@@ -259,25 +261,52 @@ __trap_fixup_kernel_data_tlb_miss:
.org TBR_TT_TRAP0
.rept 127
bra __entry_uspace_softprog_interrupt
- bra __break_step_uspace_softprog_interrupt
- .long 0,0
+ .long 0,0,0
.endr
.org TBR_TT_BREAK
bra __entry_break
.long 0,0,0
+ .section .trap.fixup.user
+ .org TBR_TT_TRAP0 >> 2
+ .rept 127
+ .long __break_step_uspace_softprog_interrupt
+ .endr
+ .org TBR_TT_BREAK >> 2
+ .long 0
+
# miscellaneous kernel mode entry points
.section .trap.kernel
.org TBR_TT_TRAP0
- .rept 127
bra __entry_kernel_softprog_interrupt
- bra __break_step_kernel_softprog_interrupt
- .long 0,0
+ .org TBR_TT_TRAP1
+ bra __entry_kernel_softprog_interrupt
+
+ # trap #2 in kernel - reenable interrupts
+ .org TBR_TT_TRAP2
+ bra __entry_kernel_external_interrupt_virtual_reenable
+
+ # miscellaneous kernel traps
+ .org TBR_TT_TRAP3
+ .rept 124
+ bra __entry_kernel_softprog_interrupt
+ .long 0,0,0
.endr
.org TBR_TT_BREAK
bra __entry_break
.long 0,0,0
+ .section .trap.fixup.kernel
+ .org TBR_TT_TRAP0 >> 2
+ .long __break_step_kernel_softprog_interrupt
+ .long __break_step_kernel_softprog_interrupt
+ .long __break_step_kernel_external_interrupt_virtual_reenable
+ .rept 124
+ .long __break_step_kernel_softprog_interrupt
+ .endr
+ .org TBR_TT_BREAK >> 2
+ .long 0
+
# miscellaneous debug mode entry points
.section .trap.break
.org TBR_TT_BREAK
diff --git a/arch/frv/kernel/entry.S b/arch/frv/kernel/entry.S
index c69d499..1d21c8d 100644
--- a/arch/frv/kernel/entry.S
+++ b/arch/frv/kernel/entry.S
@@ -141,7 +141,10 @@ __entry_uspace_external_interrupt_reentry:
movsg gner0,gr4
movsg gner1,gr5
- stdi gr4,@(gr28,#REG_GNER0)
+ stdi.p gr4,@(gr28,#REG_GNER0)
+
+ # interrupts start off fully disabled in the interrupt handler
+ subcc gr0,gr0,gr0,icc2 /* set Z and clear C */
# set up kernel global registers
sethi.p %hi(__kernel_current_task),gr5
@@ -193,9 +196,8 @@ __entry_uspace_external_interrupt_reentry:
.type __entry_kernel_external_interrupt,@function
__entry_kernel_external_interrupt:
LEDS 0x6210
-
- sub sp,gr15,gr31
- LEDS32
+// sub sp,gr15,gr31
+// LEDS32
# set up the stack pointer
or.p sp,gr0,gr30
@@ -231,7 +233,10 @@ __entry_kernel_external_interrupt_reentry:
stdi gr24,@(gr28,#REG_GR(24))
stdi gr26,@(gr28,#REG_GR(26))
sti gr29,@(gr28,#REG_GR(29))
- stdi gr30,@(gr28,#REG_GR(30))
+ stdi.p gr30,@(gr28,#REG_GR(30))
+
+ # note virtual interrupts will be fully enabled upon return
+ subicc gr0,#1,gr0,icc2 /* clear Z, set C */
movsg tbr ,gr20
movsg psr ,gr22
@@ -267,7 +272,10 @@ __entry_kernel_external_interrupt_reentry:
movsg gner0,gr4
movsg gner1,gr5
- stdi gr4,@(gr28,#REG_GNER0)
+ stdi.p gr4,@(gr28,#REG_GNER0)
+
+ # interrupts start off fully disabled in the interrupt handler
+ subcc gr0,gr0,gr0,icc2 /* set Z and clear C */
# set the return address
sethi.p %hi(__entry_return_from_kernel_interrupt),gr4
@@ -291,6 +299,45 @@ __entry_kernel_external_interrupt_reentry:
.size __entry_kernel_external_interrupt,.-__entry_kernel_external_interrupt
+###############################################################################
+#
+# deal with interrupts that were actually virtually disabled
+# - we need to really disable them, flag the fact and return immediately
+# - if you change this, you must alter break.S also
+#
+###############################################################################
+ .balign L1_CACHE_BYTES
+ .globl __entry_kernel_external_interrupt_virtually_disabled
+ .type __entry_kernel_external_interrupt_virtually_disabled,@function
+__entry_kernel_external_interrupt_virtually_disabled:
+ movsg psr,gr30
+ andi gr30,#~PSR_PIL,gr30
+ ori gr30,#PSR_PIL_14,gr30 ; debugging interrupts only
+ movgs gr30,psr
+ subcc gr0,gr0,gr0,icc2 ; leave Z set, clear C
+ rett #0
+
+ .size __entry_kernel_external_interrupt_virtually_disabled,.-__entry_kernel_external_interrupt_virtually_disabled
+
+###############################################################################
+#
+# deal with re-enablement of interrupts that were pending when virtually re-enabled
+# - set ICC2.C, re-enable the real interrupts and return
+# - we can clear ICC2.Z because we shouldn't be here if it's not 0 [due to TIHI]
+# - if you change this, you must alter break.S also
+#
+###############################################################################
+ .balign L1_CACHE_BYTES
+ .globl __entry_kernel_external_interrupt_virtual_reenable
+ .type __entry_kernel_external_interrupt_virtual_reenable,@function
+__entry_kernel_external_interrupt_virtual_reenable:
+ movsg psr,gr30
+ andi gr30,#~PSR_PIL,gr30 ; re-enable interrupts
+ movgs gr30,psr
+ subicc gr0,#1,gr0,icc2 ; clear Z, set C
+ rett #0
+
+ .size __entry_kernel_external_interrupt_virtual_reenable,.-__entry_kernel_external_interrupt_virtual_reenable
###############################################################################
#
@@ -335,6 +382,7 @@ __entry_uspace_softprog_interrupt_reentry:
sethi.p %hi(__entry_return_from_user_exception),gr23
setlo %lo(__entry_return_from_user_exception),gr23
+
bra __entry_common
.size __entry_uspace_softprog_interrupt,.-__entry_uspace_softprog_interrupt
@@ -495,7 +543,10 @@ __entry_common:
movsg gner0,gr4
movsg gner1,gr5
- stdi gr4,@(gr28,#REG_GNER0)
+ stdi.p gr4,@(gr28,#REG_GNER0)
+
+ # set up virtual interrupt disablement
+ subicc gr0,#1,gr0,icc2 /* clear Z flag, set C flag */
# set up kernel global registers
sethi.p %hi(__kernel_current_task),gr5
diff --git a/arch/frv/kernel/head.S b/arch/frv/kernel/head.S
index c73b4fe..29a5265 100644
--- a/arch/frv/kernel/head.S
+++ b/arch/frv/kernel/head.S
@@ -513,6 +513,9 @@ __head_mmu_enabled:
movgs gr0,ccr
movgs gr0,cccr
+ # initialise the virtual interrupt handling
+ subcc gr0,gr0,gr0,icc2 /* set Z, clear C */
+
#ifdef CONFIG_MMU
movgs gr3,scr2
movgs gr3,scr3
diff --git a/arch/frv/kernel/irq.c b/arch/frv/kernel/irq.c
index 59580c5..27ab4c3 100644
--- a/arch/frv/kernel/irq.c
+++ b/arch/frv/kernel/irq.c
@@ -287,18 +287,11 @@ asmlinkage void do_IRQ(void)
struct irq_source *source;
int level, cpu;
+ irq_enter();
+
level = (__frame->tbr >> 4) & 0xf;
cpu = smp_processor_id();
-#if 0
- {
- static u32 irqcount;
- *(volatile u32 *) 0xe1200004 = ~((irqcount++ << 8) | level);
- *(volatile u16 *) 0xffc00100 = (u16) ~0x9999;
- mb();
- }
-#endif
-
if ((unsigned long) __frame - (unsigned long) (current + 1) < 512)
BUG();
@@ -308,40 +301,12 @@ asmlinkage void do_IRQ(void)
kstat_this_cpu.irqs[level]++;
- irq_enter();
-
for (source = frv_irq_levels[level].sources; source; source = source->next)
source->doirq(source);
- irq_exit();
-
__clr_MASK(level);
- /* only process softirqs if we didn't interrupt another interrupt handler */
- if ((__frame->psr & PSR_PIL) == PSR_PIL_0)
- if (local_softirq_pending())
- do_softirq();
-
-#ifdef CONFIG_PREEMPT
- local_irq_disable();
- while (--current->preempt_count == 0) {
- if (!(__frame->psr & PSR_S) ||
- current->need_resched == 0 ||
- in_interrupt())
- break;
- current->preempt_count++;
- local_irq_enable();
- preempt_schedule();
- local_irq_disable();
- }
-#endif
-
-#if 0
- {
- *(volatile u16 *) 0xffc00100 = (u16) ~0x6666;
- mb();
- }
-#endif
+ irq_exit();
} /* end do_IRQ() */
diff --git a/include/asm-frv/spr-regs.h b/include/asm-frv/spr-regs.h
index ef472f0..c2a541e 100644
--- a/include/asm-frv/spr-regs.h
+++ b/include/asm-frv/spr-regs.h
@@ -98,6 +98,7 @@
#define TBR_TT_TRAP0 (0x80 << 4)
#define TBR_TT_TRAP1 (0x81 << 4)
#define TBR_TT_TRAP2 (0x82 << 4)
+#define TBR_TT_TRAP3 (0x83 << 4)
#define TBR_TT_TRAP126 (0xfe << 4)
#define TBR_TT_BREAK (0xff << 4)
diff --git a/include/asm-frv/system.h b/include/asm-frv/system.h
index d2aea70..f72ff0c 100644
--- a/include/asm-frv/system.h
+++ b/include/asm-frv/system.h
@@ -40,8 +40,84 @@ do { \
/*
* interrupt flag manipulation
+ * - use virtual interrupt management since touching the PSR is slow
+ * - ICC2.Z: T if interrupts virtually disabled
+ * - ICC2.C: F if interrupts really disabled
+ * - if Z==1 upon interrupt:
+ * - C is set to 0
+ * - interrupts are really disabled
+ * - entry.S returns immediately
+ * - uses TIHI (TRAP if Z==0 && C==0) #2 to really reenable interrupts
+ * - if taken, the trap:
+ * - sets ICC2.C
+ * - enables interrupts
*/
-#define local_irq_disable() \
+#define local_irq_disable() \
+do { \
+ /* set Z flag, but don't change the C flag */ \
+ asm volatile(" andcc gr0,gr0,gr0,icc2 \n" \
+ : \
+ : \
+ : "memory", "icc2" \
+ ); \
+} while(0)
+
+#define local_irq_enable() \
+do { \
+ /* clear Z flag and then test the C flag */ \
+ asm volatile(" oricc gr0,#1,gr0,icc2 \n" \
+ " tihi icc2,gr0,#2 \n" \
+ : \
+ : \
+ : "memory", "icc2" \
+ ); \
+} while(0)
+
+#define local_save_flags(flags) \
+do { \
+ typecheck(unsigned long, flags); \
+ asm volatile("movsg ccr,%0" \
+ : "=r"(flags) \
+ : \
+ : "memory"); \
+ \
+ /* shift ICC2.Z to bit 0 */ \
+ flags >>= 26; \
+ \
+ /* make flags 1 if interrupts disabled, 0 otherwise */ \
+ flags &= 1UL; \
+} while(0)
+
+#define irqs_disabled() \
+ ({unsigned long flags; local_save_flags(flags); flags; })
+
+#define local_irq_save(flags) \
+do { \
+ typecheck(unsigned long, flags); \
+ local_save_flags(flags); \
+ local_irq_disable(); \
+} while(0)
+
+#define local_irq_restore(flags) \
+do { \
+ typecheck(unsigned long, flags); \
+ \
+ /* load the Z flag by turning 1 if disabled into 0 if disabled \
+ * and thus setting the Z flag but not the C flag */ \
+ asm volatile(" xoricc %0,#1,gr0,icc2 \n" \
+ /* then test Z=0 and C=0 */ \
+ " tihi icc2,gr0,#2 \n" \
+ : \
+ : "r"(flags) \
+ : "memory", "icc2" \
+ ); \
+ \
+} while(0)
+
+/*
+ * real interrupt flag manipulation
+ */
+#define __local_irq_disable() \
do { \
unsigned long psr; \
asm volatile(" movsg psr,%0 \n" \
@@ -53,7 +129,7 @@ do { \
: "memory"); \
} while(0)
-#define local_irq_enable() \
+#define __local_irq_enable() \
do { \
unsigned long psr; \
asm volatile(" movsg psr,%0 \n" \
@@ -64,7 +140,7 @@ do { \
: "memory"); \
} while(0)
-#define local_save_flags(flags) \
+#define __local_save_flags(flags) \
do { \
typecheck(unsigned long, flags); \
asm("movsg psr,%0" \
@@ -73,7 +149,7 @@ do { \
: "memory"); \
} while(0)
-#define local_irq_save(flags) \
+#define __local_irq_save(flags) \
do { \
unsigned long npsr; \
typecheck(unsigned long, flags); \
@@ -86,7 +162,7 @@ do { \
: "memory"); \
} while(0)
-#define local_irq_restore(flags) \
+#define __local_irq_restore(flags) \
do { \
typecheck(unsigned long, flags); \
asm volatile(" movgs %0,psr \n" \
@@ -95,7 +171,7 @@ do { \
: "memory"); \
} while(0)
-#define irqs_disabled() \
+#define __irqs_disabled() \
((__get_PSR() & PSR_PIL) >= PSR_PIL_14)
/*
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