diff options
Diffstat (limited to 'c/src/exec/score/cpu/hppa1.1/cpu_asm.S')
-rw-r--r-- | c/src/exec/score/cpu/hppa1.1/cpu_asm.S | 805 |
1 files changed, 0 insertions, 805 deletions
diff --git a/c/src/exec/score/cpu/hppa1.1/cpu_asm.S b/c/src/exec/score/cpu/hppa1.1/cpu_asm.S deleted file mode 100644 index 7ad9b39810..0000000000 --- a/c/src/exec/score/cpu/hppa1.1/cpu_asm.S +++ /dev/null @@ -1,805 +0,0 @@ -/* - * TODO: - * Context_switch needs to only save callee save registers - * I think this means can skip: r1, r2, r19-29, r31 - * Ref: p 3-2 of Procedure Calling Conventions Manual - * This should be #ifndef DEBUG so that debugger has - * accurate visibility into all registers - * - * This file contains the assembly code for the HPPA implementation - * of RTEMS. - * - * COPYRIGHT (c) 1994,95 by Division Incorporated - * - * The license and distribution terms for this file may be - * found in the file LICENSE in this distribution or at - * http://www.OARcorp.com/rtems/license.html. - * - * $Id$ - */ - -#include <rtems/score/hppa.h> -#include <rtems/score/cpu_asm.h> -#include <rtems/score/cpu.h> -#include <rtems/score/offsets.h> - -#if 0 -#define TEXT_SEGMENT \ - .SPACE $TEXT$ !\ - .SUBSPA $CODE$ -#define RO_SEGMENT \ - .SPACE $TEXT$ !\ - .SUBSPA $lit$ -#define DATA_SEGMENT \ - .SPACE $PRIVATE$ !\ - .SUBSPA $data$ -#define BSS_SEGMENT \ - .SPACE $PRIVATE$ !\ - .SUBSPA $bss$ -#else -#define TEXT_SEGMENT .text -#define RO_SEGMENT .rodata -#define DATA_SEGMENT .data -#define BSS_SEGMENT .bss -#endif - - - -#if 0 - .SPACE $PRIVATE$ - .SUBSPA $DATA$,QUAD=1,ALIGN=8,ACCESS=31 - .SUBSPA $BSS$,QUAD=1,ALIGN=8,ACCESS=31,ZERO,SORT=82 - .SPACE $TEXT$ - .SUBSPA $LIT$,QUAD=0,ALIGN=8,ACCESS=44 - .SUBSPA $CODE$,QUAD=0,ALIGN=8,ACCESS=44,CODE_ONLY - .SPACE $TEXT$ - .SUBSPA $CODE$ - -#endif - TEXT_SEGMENT - -/* - * Special register usage for context switch and interrupts - * Stay away from %cr28 which is used for TLB misses on 72000 - */ - -isr_arg0 .reg %cr24 -isr_r9 .reg %cr25 -isr_r8 .reg %cr26 - -/* - * Interrupt stack frame looks like this - * - * offset item - * ----------------------------------------------------------------- - * INTEGER_CONTEXT_OFFSET Context_Control - * FP_CONTEXT_OFFSET Context_Control_fp - * - * It is padded out to a multiple of 64 - */ - - -/*PAGE^L - * void _Generic_ISR_Handler() - * - * This routine provides the RTEMS interrupt management. - * - * We jump here from the interrupt vector. - * The HPPA hardware has done some stuff for us: - * PSW saved in IPSW - * PSW set to 0 - * PSW[E] set to default (0) - * PSW[M] set to 1 iff this is HPMC - * - * IIA queue is frozen (since PSW[Q] is now 0) - * privilege level promoted to 0 - * IIR, ISR, IOR potentially updated if PSW[Q] was 1 at trap - * registers GR 1,8,9,16,17,24,25 copied to shadow regs - * SHR 0 1 2 3 4 5 6 - * - * Our vector stub (in the BSP) MUST have done the following: - * - * a) Saved the original %r9 into %isr_r9 (%cr25) - * b) Placed the vector number in %r9 - * c) Was allowed to also destroy $isr_r8 (%cr26), - * but the stub was NOT allowed to destroy any other registers. - * - * The typical stub sequence (in the BSP) should look like this: - * - * a) mtctl %r9,isr_r9 ; (save r9 in cr25) - * b) ldi vector,%r9 ; (load constant vector number in r9) - * c) mtctl %r8,isr_r8 ; (save r8 in cr26) - * d) ldil L%MY_BSP_first_level_interrupt_handler,%r8 - * e) ldo R%MY_BSP_first_level_interrupt_handler(%r8),%r8 - * ; (point to BSP raw handler table) - * f) ldwx,s %r9(%r8),%r8 ; (load value from raw handler table) - * g) bv 0(%r8) ; (call raw handler: _Generic_ISR_Handler) - * h) mfctl isr_r8,%r8 ; (restore r8 from cr26 in delay slot) - * - * Optionally, steps (c) thru (h) _could_ be replaced with a single - * bl,n _Generic_ISR_Handler,%r0 - * - * - */ - .EXPORT _Generic_ISR_Handler,ENTRY,PRIV_LEV=0 -_Generic_ISR_Handler: - .PROC - .CALLINFO FRAME=0,NO_CALLS - .ENTRY - - mtctl arg0, isr_arg0 - -/* - * save interrupt state - */ - mfctl ipsw, arg0 - stw arg0, IPSW_OFFSET(sp) - - mfctl iir, arg0 - stw arg0, IIR_OFFSET(sp) - - mfctl ior, arg0 - stw arg0, IOR_OFFSET(sp) - - mfctl pcoq, arg0 - stw arg0, PCOQFRONT_OFFSET(sp) - - mtctl %r0, pcoq - mfctl pcoq, arg0 - stw arg0, PCOQBACK_OFFSET(sp) - - mfctl %sar, arg0 - stw arg0, SAR_OFFSET(sp) - -/* - * Build an interrupt frame to hold the contexts we will need. - * We have already saved the interrupt items on the stack - * - * At this point the following registers are damaged wrt the interrupt - * reg current value saved value - * ------------------------------------------------ - * arg0 scratch isr_arg0 (cr24) - * r9 vector number isr_r9 (cr25) - * - * Point to beginning of integer context and - * save the integer context - */ - stw %r1,R1_OFFSET(sp) - stw %r2,R2_OFFSET(sp) - stw %r3,R3_OFFSET(sp) - stw %r4,R4_OFFSET(sp) - stw %r5,R5_OFFSET(sp) - stw %r6,R6_OFFSET(sp) - stw %r7,R7_OFFSET(sp) - stw %r8,R8_OFFSET(sp) -/* - * skip r9 - */ - stw %r10,R10_OFFSET(sp) - stw %r11,R11_OFFSET(sp) - stw %r12,R12_OFFSET(sp) - stw %r13,R13_OFFSET(sp) - stw %r14,R14_OFFSET(sp) - stw %r15,R15_OFFSET(sp) - stw %r16,R16_OFFSET(sp) - stw %r17,R17_OFFSET(sp) - stw %r18,R18_OFFSET(sp) - stw %r19,R19_OFFSET(sp) - stw %r20,R20_OFFSET(sp) - stw %r21,R21_OFFSET(sp) - stw %r22,R22_OFFSET(sp) - stw %r23,R23_OFFSET(sp) - stw %r24,R24_OFFSET(sp) - stw %r25,R25_OFFSET(sp) -/* - * skip arg0 - */ - stw %r27,R27_OFFSET(sp) - stw %r28,R28_OFFSET(sp) - stw %r29,R29_OFFSET(sp) - stw %r30,R30_OFFSET(sp) - stw %r31,R31_OFFSET(sp) - -/* Now most registers are available since they have been saved - * - * The following items are currently wrong in the integer context - * reg current value saved value - * ------------------------------------------------ - * arg0 scratch isr_arg0 (cr24) - * r9 vector number isr_r9 (cr25) - * - * Fix them - */ - - mfctl isr_arg0,%r3 - stw %r3,ARG0_OFFSET(sp) - - mfctl isr_r9,%r3 - stw %r3,R9_OFFSET(sp) - -/* - * At this point we are done with isr_arg0, and isr_r9 control registers - * - * Prepare to re-enter virtual mode - * We need Q in case the interrupt handler enables interrupts - */ - - ldil L%CPU_PSW_DEFAULT, arg0 - ldo R%CPU_PSW_DEFAULT(arg0), arg0 - mtctl arg0, ipsw - -/* - * Now jump to "rest_of_isr_handler" with the rfi - * We are assuming the space queues are all correct already - */ - - ldil L%rest_of_isr_handler, arg0 - ldo R%rest_of_isr_handler(arg0), arg0 - mtctl arg0, pcoq - ldo 4(arg0), arg0 - mtctl arg0, pcoq - - rfi - nop - -/* - * At this point we are back in virtual mode and all our - * normal addressing is once again ok. - * - * It is now ok to take an exception or trap - */ - -rest_of_isr_handler: - -/* - * Point to beginning of float context and - * save the floating point context -- doing whatever patches are necessary - */ - - .call ARGW0=GR - bl _CPU_Save_float_context,%r2 - ldo FP_CONTEXT_OFFSET(sp),arg0 - -/* - * save the ptr to interrupt frame as an argument for the interrupt handler - */ - - copy sp, arg1 - -/* - * Advance the frame to point beyond all interrupt contexts (integer & float) - * this also includes the pad to align to 64byte stack boundary - */ - ldo CPU_INTERRUPT_FRAME_SIZE(sp), sp - -/* - * r3 -- &_ISR_Nest_level - * r5 -- value _ISR_Nest_level - * r4 -- &_Thread_Dispatch_disable_level - * r6 -- value _Thread_Dispatch_disable_level - * r9 -- vector number - */ - - .import _ISR_Nest_level,data - ldil L%_ISR_Nest_level,%r3 - ldo R%_ISR_Nest_level(%r3),%r3 - ldw 0(%r3),%r5 - - .import _Thread_Dispatch_disable_level,data - ldil L%_Thread_Dispatch_disable_level,%r4 - ldo R%_Thread_Dispatch_disable_level(%r4),%r4 - ldw 0(%r4),%r6 - -/* - * increment interrupt nest level counter. If outermost interrupt - * switch the stack and squirrel away the previous sp. - */ - addi 1,%r5,%r5 - stw %r5, 0(%r3) - -/* - * compute and save new stack (with frame) - * just in case we are nested -- simpler this way - */ - comibf,= 1,%r5,stack_done - ldo 128(sp),%r7 - -/* - * Switch to interrupt stack allocated by the interrupt manager (intr.c) - */ - .import _CPU_Interrupt_stack_low,data - ldil L%_CPU_Interrupt_stack_low,%r7 - ldw R%_CPU_Interrupt_stack_low(%r7),%r7 - ldo 128(%r7),%r7 - -stack_done: -/* - * save our current stack pointer where the "old sp" is supposed to be - */ - stw sp, -4(%r7) -/* - * and switch stacks (or advance old stack in nested case) - */ - copy %r7, sp - -/* - * increment the dispatch disable level counter. - */ - addi 1,%r6,%r6 - stw %r6, 0(%r4) - -/* - * load address of user handler - * Note: No error checking is done, it is assumed that the - * vector table contains a valid address or a stub - * spurious handler. - */ - .import _ISR_Vector_table,data - ldil L%_ISR_Vector_table,%r8 - ldo R%_ISR_Vector_table(%r8),%r8 - ldw 0(%r8),%r8 - ldwx,s %r9(%r8),%r8 - -/* - * invoke user interrupt handler - * Interrupts are currently disabled, as per RTEMS convention - * The handler has the option of re-enabling interrupts - * NOTE: can not use 'bl' since it uses "pc-relative" addressing - * and we are using a hard coded address from a table - * So... we fudge r2 ourselves (ala dynacall) - * arg0 = vector number, arg1 = ptr to rtems_interrupt_frame - */ - copy %r9, %r26 - .call ARGW0=GR, ARGW1=GR - blr %r0, rp - bv,n 0(%r8) - -post_user_interrupt_handler: - -/* - * Back from user handler(s) - * Disable external interrupts (since the interrupt handler could - * have turned them on) and return to the interrupted task stack (assuming - * (_ISR_Nest_level == 0) - */ - - rsm HPPA_PSW_I + HPPA_PSW_R, %r0 - ldw -4(sp), sp - -/* - * r3 -- (most of) &_ISR_Nest_level - * r5 -- value _ISR_Nest_level - * r4 -- (most of) &_Thread_Dispatch_disable_level - * r6 -- value _Thread_Dispatch_disable_level - * r7 -- (most of) &_ISR_Signals_to_thread_executing - * r8 -- value _ISR_Signals_to_thread_executing - */ - - .import _ISR_Nest_level,data - ldil L%_ISR_Nest_level,%r3 - ldw R%_ISR_Nest_level(%r3),%r5 - - .import _Thread_Dispatch_disable_level,data - ldil L%_Thread_Dispatch_disable_level,%r4 - ldw R%_Thread_Dispatch_disable_level(%r4),%r6 - - .import _ISR_Signals_to_thread_executing,data - ldil L%_ISR_Signals_to_thread_executing,%r7 - -/* - * decrement isr nest level - */ - addi -1, %r5, %r5 - stw %r5, R%_ISR_Nest_level(%r3) - -/* - * decrement dispatch disable level counter and, if not 0, go on - */ - addi -1,%r6,%r6 - comibf,= 0,%r6,isr_restore - stw %r6, R%_Thread_Dispatch_disable_level(%r4) - -/* - * check whether or not a context switch is necessary - */ - .import _Context_Switch_necessary,data - ldil L%_Context_Switch_necessary,%r8 - ldw R%_Context_Switch_necessary(%r8),%r8 - comibf,=,n 0,%r8,ISR_dispatch - -/* - * check whether or not a context switch is necessary because an ISR - * sent signals to the interrupted task - */ - ldw R%_ISR_Signals_to_thread_executing(%r7),%r8 - comibt,=,n 0,%r8,isr_restore - - -/* - * OK, something happened while in ISR and we need to switch to a task - * other than the one which was interrupted or the - * ISR_Signals_to_thread_executing case - * We also turn on interrupts, since the interrupted task had them - * on (obviously :-) and Thread_Dispatch is happy to leave ints on. - */ - -ISR_dispatch: - stw %r0, R%_ISR_Signals_to_thread_executing(%r7) - - ssm HPPA_PSW_I, %r0 - - .import _Thread_Dispatch,code - .call - bl _Thread_Dispatch,%r2 - ldo 128(sp),sp - - ldo -128(sp),sp - -isr_restore: - -/* - * enable interrupts during most of restore - */ - ssm HPPA_PSW_I, %r0 - -/* - * Get a pointer to beginning of our stack frame - */ - ldo -CPU_INTERRUPT_FRAME_SIZE(sp), %arg1 - -/* - * restore float - */ - .call ARGW0=GR - bl _CPU_Restore_float_context,%r2 - ldo FP_CONTEXT_OFFSET(%arg1), arg0 - - copy %arg1, %arg0 - -/* - * ********** FALL THRU ********** - */ - -/* - * Jump here from bottom of Context_Switch - * Also called directly by _CPU_Context_Restart_self via _Thread_Restart_self - * restore interrupt state - */ - - .EXPORT _CPU_Context_restore -_CPU_Context_restore: - -/* - * restore integer state - */ - ldw R1_OFFSET(arg0),%r1 - ldw R2_OFFSET(arg0),%r2 - ldw R3_OFFSET(arg0),%r3 - ldw R4_OFFSET(arg0),%r4 - ldw R5_OFFSET(arg0),%r5 - ldw R6_OFFSET(arg0),%r6 - ldw R7_OFFSET(arg0),%r7 - ldw R8_OFFSET(arg0),%r8 - ldw R9_OFFSET(arg0),%r9 - ldw R10_OFFSET(arg0),%r10 - ldw R11_OFFSET(arg0),%r11 - ldw R12_OFFSET(arg0),%r12 - ldw R13_OFFSET(arg0),%r13 - ldw R14_OFFSET(arg0),%r14 - ldw R15_OFFSET(arg0),%r15 - ldw R16_OFFSET(arg0),%r16 - ldw R17_OFFSET(arg0),%r17 - ldw R18_OFFSET(arg0),%r18 - ldw R19_OFFSET(arg0),%r19 - ldw R20_OFFSET(arg0),%r20 - ldw R21_OFFSET(arg0),%r21 - ldw R22_OFFSET(arg0),%r22 - ldw R23_OFFSET(arg0),%r23 - ldw R24_OFFSET(arg0),%r24 -/* - * skipping r25; used as scratch register below - * skipping r26 (arg0) until we are done with it - */ - ldw R27_OFFSET(arg0),%r27 - ldw R28_OFFSET(arg0),%r28 - ldw R29_OFFSET(arg0),%r29 -/* - * skipping r30 (sp) until we turn off interrupts - */ - ldw R31_OFFSET(arg0),%r31 - -/* - * Turn off Q & R & I so we can write r30 and interrupt control registers - */ - rsm HPPA_PSW_Q + HPPA_PSW_R + HPPA_PSW_I, %r0 - -/* - * now safe to restore r30 - */ - ldw R30_OFFSET(arg0),%r30 - - ldw IPSW_OFFSET(arg0), %r25 - mtctl %r25, ipsw - - ldw SAR_OFFSET(arg0), %r25 - mtctl %r25, sar - - ldw PCOQFRONT_OFFSET(arg0), %r25 - mtctl %r25, pcoq - - ldw PCOQBACK_OFFSET(arg0), %r25 - mtctl %r25, pcoq - -/* - * Load r25 with interrupts off - */ - ldw R25_OFFSET(arg0),%r25 -/* - * Must load r26 (arg0) last - */ - ldw R26_OFFSET(arg0),%r26 - -isr_exit: - rfi - .EXIT - .PROCEND - -/* - * This section is used to context switch floating point registers. - * Ref: 6-35 of Architecture 1.1 - * - * NOTE: since integer multiply uses the floating point unit, - * we have to save/restore fp on every trap. We cannot - * just try to keep track of fp usage. - */ - - .align 32 - .EXPORT _CPU_Save_float_context,ENTRY,PRIV_LEV=0 -_CPU_Save_float_context: - .PROC - .CALLINFO FRAME=0,NO_CALLS - .ENTRY - fstds,ma %fr0,8(%arg0) - fstds,ma %fr1,8(%arg0) - fstds,ma %fr2,8(%arg0) - fstds,ma %fr3,8(%arg0) - fstds,ma %fr4,8(%arg0) - fstds,ma %fr5,8(%arg0) - fstds,ma %fr6,8(%arg0) - fstds,ma %fr7,8(%arg0) - fstds,ma %fr8,8(%arg0) - fstds,ma %fr9,8(%arg0) - fstds,ma %fr10,8(%arg0) - fstds,ma %fr11,8(%arg0) - fstds,ma %fr12,8(%arg0) - fstds,ma %fr13,8(%arg0) - fstds,ma %fr14,8(%arg0) - fstds,ma %fr15,8(%arg0) - fstds,ma %fr16,8(%arg0) - fstds,ma %fr17,8(%arg0) - fstds,ma %fr18,8(%arg0) - fstds,ma %fr19,8(%arg0) - fstds,ma %fr20,8(%arg0) - fstds,ma %fr21,8(%arg0) - fstds,ma %fr22,8(%arg0) - fstds,ma %fr23,8(%arg0) - fstds,ma %fr24,8(%arg0) - fstds,ma %fr25,8(%arg0) - fstds,ma %fr26,8(%arg0) - fstds,ma %fr27,8(%arg0) - fstds,ma %fr28,8(%arg0) - fstds,ma %fr29,8(%arg0) - fstds,ma %fr30,8(%arg0) - fstds %fr31,0(%arg0) - bv 0(%r2) - addi -(31*8), %arg0, %arg0 ; restore arg0 just for fun - .EXIT - .PROCEND - - .align 32 - .EXPORT _CPU_Restore_float_context,ENTRY,PRIV_LEV=0 -_CPU_Restore_float_context: - .PROC - .CALLINFO FRAME=0,NO_CALLS - .ENTRY - addi (31*8), %arg0, %arg0 ; point at last double - fldds 0(%arg0),%fr31 - fldds,mb -8(%arg0),%fr30 - fldds,mb -8(%arg0),%fr29 - fldds,mb -8(%arg0),%fr28 - fldds,mb -8(%arg0),%fr27 - fldds,mb -8(%arg0),%fr26 - fldds,mb -8(%arg0),%fr25 - fldds,mb -8(%arg0),%fr24 - fldds,mb -8(%arg0),%fr23 - fldds,mb -8(%arg0),%fr22 - fldds,mb -8(%arg0),%fr21 - fldds,mb -8(%arg0),%fr20 - fldds,mb -8(%arg0),%fr19 - fldds,mb -8(%arg0),%fr18 - fldds,mb -8(%arg0),%fr17 - fldds,mb -8(%arg0),%fr16 - fldds,mb -8(%arg0),%fr15 - fldds,mb -8(%arg0),%fr14 - fldds,mb -8(%arg0),%fr13 - fldds,mb -8(%arg0),%fr12 - fldds,mb -8(%arg0),%fr11 - fldds,mb -8(%arg0),%fr10 - fldds,mb -8(%arg0),%fr9 - fldds,mb -8(%arg0),%fr8 - fldds,mb -8(%arg0),%fr7 - fldds,mb -8(%arg0),%fr6 - fldds,mb -8(%arg0),%fr5 - fldds,mb -8(%arg0),%fr4 - fldds,mb -8(%arg0),%fr3 - fldds,mb -8(%arg0),%fr2 - fldds,mb -8(%arg0),%fr1 - bv 0(%r2) - fldds,mb -8(%arg0),%fr0 - .EXIT - .PROCEND - -/* - * These 2 small routines are unused right now. - * Normally we just go thru _CPU_Save_float_context (and Restore) - * - * Here we just deref the ptr and jump up, letting _CPU_Save_float_context - * do the return for us. - */ - - .EXPORT _CPU_Context_save_fp,ENTRY,PRIV_LEV=0 -_CPU_Context_save_fp: - .PROC - .CALLINFO FRAME=0,NO_CALLS - .ENTRY - bl _CPU_Save_float_context, %r0 - ldw 0(%arg0), %arg0 - .EXIT - .PROCEND - - .EXPORT _CPU_Context_restore_fp,ENTRY,PRIV_LEV=0 -_CPU_Context_restore_fp: - .PROC - .CALLINFO FRAME=0,NO_CALLS - .ENTRY - bl _CPU_Restore_float_context, %r0 - ldw 0(%arg0), %arg0 - .EXIT - .PROCEND - - -/* - * void _CPU_Context_switch( run_context, heir_context ) - * - * This routine performs a normal non-FP context switch. - */ - - .align 32 - .EXPORT _CPU_Context_switch,ENTRY,PRIV_LEV=0,ARGW0=GR,ARGW1=GR -_CPU_Context_switch: - .PROC - .CALLINFO FRAME=64 - .ENTRY - -/* - * Save the integer context - */ - stw %r1,R1_OFFSET(arg0) - stw %r2,R2_OFFSET(arg0) - stw %r3,R3_OFFSET(arg0) - stw %r4,R4_OFFSET(arg0) - stw %r5,R5_OFFSET(arg0) - stw %r6,R6_OFFSET(arg0) - stw %r7,R7_OFFSET(arg0) - stw %r8,R8_OFFSET(arg0) - stw %r9,R9_OFFSET(arg0) - stw %r10,R10_OFFSET(arg0) - stw %r11,R11_OFFSET(arg0) - stw %r12,R12_OFFSET(arg0) - stw %r13,R13_OFFSET(arg0) - stw %r14,R14_OFFSET(arg0) - stw %r15,R15_OFFSET(arg0) - stw %r16,R16_OFFSET(arg0) - stw %r17,R17_OFFSET(arg0) - stw %r18,R18_OFFSET(arg0) - stw %r19,R19_OFFSET(arg0) - stw %r20,R20_OFFSET(arg0) - stw %r21,R21_OFFSET(arg0) - stw %r22,R22_OFFSET(arg0) - stw %r23,R23_OFFSET(arg0) - stw %r24,R24_OFFSET(arg0) - stw %r25,R25_OFFSET(arg0) - stw %r26,R26_OFFSET(arg0) - stw %r27,R27_OFFSET(arg0) - stw %r28,R28_OFFSET(arg0) - stw %r29,R29_OFFSET(arg0) - stw %r30,R30_OFFSET(arg0) - stw %r31,R31_OFFSET(arg0) - -/* - * fill in interrupt context section - */ - stw %r2, PCOQFRONT_OFFSET(%arg0) - ldo 4(%r2), %r2 - stw %r2, PCOQBACK_OFFSET(%arg0) - -/* - * Generate a suitable IPSW by using the system default psw - * with the current low bits added in. - */ - - ldil L%CPU_PSW_DEFAULT, %r2 - ldo R%CPU_PSW_DEFAULT(%r2), %r2 - ssm 0, %arg2 - dep %arg2, 31, 8, %r2 - stw %r2, IPSW_OFFSET(%arg0) - -/* - * at this point, the running task context is completely saved - * Now jump to the bottom of the interrupt handler to load the - * heirs context - */ - - b _CPU_Context_restore - copy %arg1, %arg0 - - .EXIT - .PROCEND - - -/* - * Find first bit - * NOTE: - * This is used (and written) only for the ready chain code and - * priority bit maps. - * Any other use constitutes fraud. - * Returns first bit from the least significant side. - * Eg: if input is 0x8001 - * output will indicate the '1' bit and return 0. - * This is counter to HPPA bit numbering which calls this - * bit 31. This way simplifies the macros _CPU_Priority_Mask - * and _CPU_Priority_Bits_index. - * - * NOTE: - * We just use 16 bit version - * does not handle zero case - * - * Based on the UTAH Mach libc version of ffs. - */ - - .align 32 - .EXPORT hppa_rtems_ffs,ENTRY,PRIV_LEV=0,ARGW0=GR -hppa_rtems_ffs: - .PROC - .CALLINFO FRAME=0,NO_CALLS - .ENTRY - -#ifdef RETURN_ERROR_ON_ZERO - comb,= %arg0,%r0,ffsdone ; If arg0 is 0 - ldi -1,%ret0 ; return -1 -#endif - -#if BITFIELD_SIZE == 32 - ldi 31,%ret0 ; Set return to high bit - extru,= %arg0,31,16,%r0 ; If low 16 bits are non-zero - addi,tr -16,%ret0,%ret0 ; subtract 16 from bitpos - shd %r0,%arg0,16,%arg0 ; else shift right 16 bits -#else - ldi 15,%ret0 ; Set return to high bit -#endif - extru,= %arg0,31,8,%r0 ; If low 8 bits are non-zero - addi,tr -8,%ret0,%ret0 ; subtract 8 from bitpos - shd %r0,%arg0,8,%arg0 ; else shift right 8 bits - extru,= %arg0,31,4,%r0 ; If low 4 bits are non-zero - addi,tr -4,%ret0,%ret0 ; subtract 4 from bitpos - shd %r0,%arg0,4,%arg0 ; else shift right 4 bits - extru,= %arg0,31,2,%r0 ; If low 2 bits are non-zero - addi,tr -2,%ret0,%ret0 ; subtract 2 from bitpos - shd %r0,%arg0,2,%arg0 ; else shift right 2 bits - extru,= %arg0,31,1,%r0 ; If low bit is non-zero - addi -1,%ret0,%ret0 ; subtract 1 from bitpos -ffsdone: - bv,n 0(%r2) - nop - .EXIT - .PROCEND |