diff options
Diffstat (limited to 'arch/mips/kernel/smtc-asm.S')
-rw-r--r-- | arch/mips/kernel/smtc-asm.S | 133 |
1 files changed, 0 insertions, 133 deletions
diff --git a/arch/mips/kernel/smtc-asm.S b/arch/mips/kernel/smtc-asm.S deleted file mode 100644 index 2866863a39df..000000000000 --- a/arch/mips/kernel/smtc-asm.S +++ /dev/null @@ -1,133 +0,0 @@ -/* - * Assembly Language Functions for MIPS MT SMTC support - */ - -/* - * This file should be built into the kernel only if CONFIG_MIPS_MT_SMTC is set. */ - -#include <asm/regdef.h> -#include <asm/asmmacro.h> -#include <asm/stackframe.h> -#include <asm/irqflags.h> - -/* - * "Software Interrupt" linkage. - * - * This is invoked when an "Interrupt" is sent from one TC to another, - * where the TC to be interrupted is halted, has it's Restart address - * and Status values saved by the "remote control" thread, then modified - * to cause execution to begin here, in kenel mode. This code then - * disguises the TC state as that of an exception and transfers - * control to the general exception or vectored interrupt handler. - */ - .set noreorder - -/* -The __smtc_ipi_vector would use k0 and k1 as temporaries and -1) Set EXL (this is per-VPE, so this can't be done by proxy!) -2) Restore the K/CU and IXMT bits to the pre "exception" state - (EXL means no interrupts and access to the kernel map). -3) Set EPC to be the saved value of TCRestart. -4) Jump to the exception handler entry point passed by the sender. - -CAN WE PROVE THAT WE WON'T DO THIS IF INTS DISABLED?? -*/ - -/* - * Reviled and slandered vision: Set EXL and restore K/CU/IXMT - * state of pre-halt thread, then save everything and call - * thought some function pointer to imaginary_exception, which - * will parse a register value or memory message queue to - * deliver things like interprocessor interrupts. On return - * from that function, jump to the global ret_from_irq code - * to invoke the scheduler and return as appropriate. - */ - -#define PT_PADSLOT4 (PT_R0-8) -#define PT_PADSLOT5 (PT_R0-4) - - .text - .align 5 -FEXPORT(__smtc_ipi_vector) -#ifdef CONFIG_CPU_MICROMIPS - nop -#endif - .set noat - /* Disable thread scheduling to make Status update atomic */ - DMT 27 # dmt k1 - _ehb - /* Set EXL */ - mfc0 k0,CP0_STATUS - ori k0,k0,ST0_EXL - mtc0 k0,CP0_STATUS - _ehb - /* Thread scheduling now inhibited by EXL. Restore TE state. */ - andi k1,k1,VPECONTROL_TE - beqz k1,1f - emt -1: - /* - * The IPI sender has put some information on the anticipated - * kernel stack frame. If we were in user mode, this will be - * built above the saved kernel SP. If we were already in the - * kernel, it will be built above the current CPU SP. - * - * Were we in kernel mode, as indicated by CU0? - */ - sll k1,k0,3 - .set noreorder - bltz k1,2f - move k1,sp - .set reorder - /* - * If previously in user mode, set CU0 and use kernel stack. - */ - li k1,ST0_CU0 - or k1,k1,k0 - mtc0 k1,CP0_STATUS - _ehb - get_saved_sp - /* Interrupting TC will have pre-set values in slots in the new frame */ -2: subu k1,k1,PT_SIZE - /* Load TCStatus Value */ - lw k0,PT_TCSTATUS(k1) - /* Write it to TCStatus to restore CU/KSU/IXMT state */ - mtc0 k0,$2,1 - _ehb - lw k0,PT_EPC(k1) - mtc0 k0,CP0_EPC - /* Save all will redundantly recompute the SP, but use it for now */ - SAVE_ALL - CLI - TRACE_IRQS_OFF - /* Function to be invoked passed stack pad slot 5 */ - lw t0,PT_PADSLOT5(sp) - /* Argument from sender passed in stack pad slot 4 */ - lw a0,PT_PADSLOT4(sp) - LONG_L s0, TI_REGS($28) - LONG_S sp, TI_REGS($28) - PTR_LA ra, ret_from_irq - jr t0 - -/* - * Called from idle loop to provoke processing of queued IPIs - * First IPI message in queue passed as argument. - */ - -LEAF(self_ipi) - /* Before anything else, block interrupts */ - mfc0 t0,CP0_TCSTATUS - ori t1,t0,TCSTATUS_IXMT - mtc0 t1,CP0_TCSTATUS - _ehb - /* We know we're in kernel mode, so prepare stack frame */ - subu t1,sp,PT_SIZE - sw ra,PT_EPC(t1) - sw a0,PT_PADSLOT4(t1) - la t2,ipi_decode - sw t2,PT_PADSLOT5(t1) - /* Save pre-disable value of TCStatus */ - sw t0,PT_TCSTATUS(t1) - j __smtc_ipi_vector - nop -END(self_ipi) |