// TITLE("Cache Flush") //++ // // Copyright (c) 1991 Microsoft Corporation // // Module Name: // // j4cache.s // // Abstract: // // This module implements the code necessary for cache operations on // a MIPS R4000. // // Author: // // David N. Cutler (davec) 19-Dec-1991 // // Environment: // // Kernel mode only. // // Revision History: // //-- #include "halmips.h" // // Define cache operations constants. // #define COLOR_BITS (7 << PAGE_SHIFT) // color bit (R4000 - 8kb cache) #define COLOR_MASK (0x7fff) // color mask (R4000 - 8kb cache) #define FLUSH_BASE 0xfffe0000 // flush base address #define PROTECTION_BITS ((1 << ENTRYLO_V) | (1 << ENTRYLO_D)) // SBTTL("Change Color Page") //++ // // VOID // HalChangeColorPage ( // IN PVOID NewColor, // IN PVOID OldColor, // IN ULONG PageFrame // ) // // Routine Description: // // This function changes the color of a page if the old and new colors // do not match. // // The algorithm used to change colors for a page is as follows: // // 1. Purge (hit/invalidate) the page from the instruction cache // using the old color. // // 2. Purge (hit/invalidate) the page from the data cache using // the old color. // // Arguments: // // NewColor (a0) - Supplies the page aligned virtual address of the // new color of the page to change. // // OldColor (a1) - Supplies the page aligned virtual address of the // old color of the page to change. // // PageFrame (a2) - Supplies the page frame number of the page that // is changed. // // Return Value: // // None. // //-- .struct 0 .space 3 * 4 // fill CpRa: .space 4 // saved return address CpFrameLength: // length of stack frame CpA0: .space 4 // (a0) CpA1: .space 4 // (a1) CpA2: .space 4 // (a2) CpA3: .space 4 // (a3) NESTED_ENTRY(HalChangeColorPage, CpFrameLength, zero) subu sp,sp,CpFrameLength // allocate stack frame sw ra,CpRa(sp) // save return address PROLOGUE_END and a0,a0,COLOR_BITS // isolate new color bits and a1,a1,COLOR_BITS // isolate old color bits beq a0,a1,10f // if eq, colors match sw a1,CpA1(sp) // save old color bits sw a2,CpA2(sp) // save page frame // // Purge the instruction cache using the old page color. // move a0,a1 // set color value move a1,a2 // set page frame number li a2,PAGE_SIZE // set length of purge jal HalPurgeIcachePage // purge instruction cache page // // Flush the data cache using the old page color. // lw a0,CpA1(sp) // get old color bits lw a1,CpA2(sp) // get page frame number li a2,PAGE_SIZE // set length of purge jal HalFlushDcachePage // purge data cache page 10: lw ra,CpRa(sp) // get return address addu sp,sp,CpFrameLength // deallocate stack frame j ra // return .end HalChangeColorPage SBTTL("Flush Data Cache Page") //++ // // VOID // HalFlushDcachePage ( // IN PVOID Color, // IN ULONG PageFrame, // IN ULONG Length // ) // // Routine Description: // // This function flushes (hit/writeback/invalidate) up to a page of data // from the data cache. // // Arguments: // // Color (a0) - Supplies the starting virtual address and color of the // data that is flushed. // // PageFrame (a1) - Supplies the page frame number of the page that // is flushed. // // Length (a2) - Supplies the length of the region in the page that is // flushed. // // Return Value: // // None. // //-- LEAF_ENTRY(HalFlushDcachePage) #if DBG lw t0,KeDcacheFlushCount // get address of dcache flush count lw t1,0(t0) // increment the count of flushes addu t1,t1,1 // sw t1,0(t0) // store result #endif .set noreorder .set noat lw v0,KiPcr + PcAlignedCachePolicy(zero) // get cache policy and a0,a0,COLOR_MASK // isolate color and offset bits li t0,FLUSH_BASE // get base flush address or t0,t0,a0 // compute color virtual address sll t1,a1,ENTRYLO_PFN // shift page frame into position or t1,t1,PROTECTION_BITS // merge protection bits or t1,t1,v0 // merge cache policy and a0,a0,0x1000 // isolate TB entry index beql zero,a0,10f // if eq, first entry move t2,zero // set second page table entry move t2,t1 // set second page table entry move t1,zero // set first page table entry 10: mfc0 t3,wired // get TB entry index lw v0,KiPcr + PcSecondLevelDcacheFillSize(zero) // get 2nd fill size lw t4,KiPcr + PcFirstLevelDcacheFillSize(zero) // get 1st fill size bnel zero,v0,15f // if ne, second level cache present move t4,v0 // set flush block size .set at .set reorder // // Flush a page from the data cache. // 15: DISABLE_INTERRUPTS(t5) // disable interrupts .set noreorder .set noat mfc0 t6,entryhi // get current PID and VPN2 srl t7,t0,ENTRYHI_VPN2 // isolate VPN2 of virtual address sll t7,t7,ENTRYHI_VPN2 // and t6,t6,0xff << ENTRYHI_PID // isolate current PID or t7,t7,t6 // merge PID with VPN2 of virtual address mtc0 t7,entryhi // set VPN2 and PID for probe mtc0 t1,entrylo0 // set first PTE value mtc0 t2,entrylo1 // set second PTE value mtc0 t3,index // set TB index value nop // fill tlbwi // write TB entry - 3 cycle hazzard subu t6,t4,1 // compute block size minus one and t7,t0,t6 // compute offset in block addu a2,a2,t6 // round up to next block addu a2,a2,t7 // nor t6,t6,zero // complement block size minus one and a2,a2,t6 // truncate length to even number beq zero,a2,30f // if eq, no blocks to flush and t8,t0,t6 // compute starting virtual address addu t9,t8,a2 // compute ending virtual address bne zero,v0,40f // if ne, second level cache present subu t9,t9,t4 // compute ending loop address // // Flush the primary data cache only. // 20: cache HIT_WRITEBACK_INVALIDATE_D,0(t8) // invalidate cache block bne t8,t9,20b // if ne, more blocks to invalidate addu t8,t8,t4 // compute next block address .set at .set reorder 30: ENABLE_INTERRUPTS(t5) // enable interrupts j ra // return // // Flush the primary and secondary data caches. // .set noreorder .set noat 40: cache HIT_WRITEBACK_INVALIDATE_SD,0(t8) // invalidate cache block bne t8,t9,40b // if ne, more blocks to invalidate addu t8,t8,t4 // compute next block address .set at .set reorder ENABLE_INTERRUPTS(t5) // enable interrupts j ra // return .end HalFlushDcachePage SBTTL("Purge Data Cache Page") //++ // // VOID // HalPurgeDcachePage ( // IN PVOID Color, // IN ULONG PageFrame, // IN ULONG Length // ) // // Routine Description: // // This function purges (hit/invalidate) up to a page of data from the // data cache. // // Arguments: // // Color (a0) - Supplies the starting virtual address and color of the // data that is purged. // // PageFrame (a1) - Supplies the page frame number of the page that // is purged. // // Length (a2) - Supplies the length of the region in the page that is // purged. // // Return Value: // // None. // //-- LEAF_ENTRY(HalPurgeDcachePage) #if DBG lw t0,KeDcacheFlushCount // get address of dcache flush count lw t1,0(t0) // increment the count of flushes addu t1,t1,1 // sw t1,0(t0) // store result #endif .set noreorder .set noat lw v0,KiPcr + PcAlignedCachePolicy(zero) // get cache policy and a0,a0,COLOR_MASK // isolate color bits li t0,FLUSH_BASE // get base flush address or t0,t0,a0 // compute color virtual address sll t1,a1,ENTRYLO_PFN // shift page frame into position or t1,t1,PROTECTION_BITS // merge protection bits or t1,t1,v0 // merge cache policy and a0,a0,0x1000 // isolate TB entry index beql zero,a0,10f // if eq, first entry move t2,zero // set second page table entry move t2,t1 // set second page table entry move t1,zero // set first page table entry 10: mfc0 t3,wired // get TB entry index lw v0,KiPcr + PcSecondLevelDcacheFillSize(zero) // get 2nd fill size lw t4,KiPcr + PcFirstLevelDcacheFillSize(zero) // get 1st fill size bnel zero,v0,15f // if ne, second level cache present move t4,v0 // set purge block size .set at .set reorder // // Purge data from the data cache. // 15: DISABLE_INTERRUPTS(t5) // disable interrupts .set noreorder .set noat mfc0 t6,entryhi // get current PID and VPN2 srl t7,t0,ENTRYHI_VPN2 // isolate VPN2 of virtual address sll t7,t7,ENTRYHI_VPN2 // and t6,t6,0xff << ENTRYHI_PID // isolate current PID or t7,t7,t6 // merge PID with VPN2 of virtual address mtc0 t7,entryhi // set VPN2 and PID for probe mtc0 t1,entrylo0 // set first PTE value mtc0 t2,entrylo1 // set second PTE value mtc0 t3,index // set TB index value nop // fill tlbwi // write TB entry - 3 cycle hazzard subu t6,t4,1 // compute block size minus one and t7,t0,t6 // compute offset in block addu a2,a2,t6 // round up to next block addu a2,a2,t7 // nor t6,t6,zero // complement block size minus one and a2,a2,t6 // truncate length to even number beq zero,a2,30f // if eq, no blocks to purge and t8,t0,t6 // compute starting virtual address addu t9,t8,a2 // compute ending virtual address bne zero,v0,40f // if ne, second level cache present subu t9,t9,t4 // compute ending loop address // // Purge the primary data cache only. // 20: cache HIT_INVALIDATE_D,0(t8) // invalidate cache block bne t8,t9,20b // if ne, more blocks to invalidate addu t8,t8,t4 // compute next block address .set at .set reorder 30: ENABLE_INTERRUPTS(t5) // enable interrupts j ra // return // // Purge the primary and secondary data caches. // .set noreorder .set noat 40: cache HIT_INVALIDATE_SD,0(t8) // invalidate cache block bne t8,t9,40b // if ne, more blocks to invalidate addu t8,t8,t4 // compute next block address .set at .set reorder ENABLE_INTERRUPTS(t5) // enable interrupts j ra // return .end HalPurgeDcachePage SBTTL("Purge Instruction Cache Page") //++ // // VOID // HalPurgeIcachePage ( // IN PVOID Color, // IN ULONG PageFrame, // IN ULONG Length // ) // // Routine Description: // // This function purges (hit/invalidate) up to a page fo data from the // instruction cache. // // Arguments: // // Color (a0) - Supplies the starting virtual address and color of the // data that is purged. // // PageFrame (a1) - Supplies the page frame number of the page that // is purged. // // Length (a2) - Supplies the length of the region in the page that is // purged. // // Return Value: // // None. // //-- LEAF_ENTRY(HalPurgeIcachePage) #if DBG lw t0,KeIcacheFlushCount // get address of icache flush count lw t1,0(t0) // increment the count of flushes addu t1,t1,1 // sw t1,0(t0) // store result #endif .set noreorder .set noat lw v0,KiPcr + PcAlignedCachePolicy(zero) // get cache policy and a0,a0,COLOR_MASK // isolate color bits li t0,FLUSH_BASE // get base flush address or t0,t0,a0 // compute color virtual address sll t1,a1,ENTRYLO_PFN // shift page frame into position or t1,t1,PROTECTION_BITS // merge protection bits or t1,t1,v0 // merge cache policy and a0,a0,0x1000 // isolate TB entry index beql zero,a0,10f // if eq, first entry move t2,zero // set second page table entry move t2,t1 // set second page table entry move t1,zero // set first page table entry 10: mfc0 t3,wired // get TB entry index lw v0,KiPcr + PcSecondLevelIcacheFillSize(zero) // get 2nd fill size lw t4,KiPcr + PcFirstLevelIcacheFillSize(zero) // get 1st fill size bnel zero,v0,15f // if ne, second level cache present move t4,v0 // set purge block size .set at .set reorder // // Purge data from the instruction cache. // 15: DISABLE_INTERRUPTS(t5) // disable interrupts .set noreorder .set noat mfc0 t6,entryhi // get current PID and VPN2 srl t7,t0,ENTRYHI_VPN2 // isolate VPN2 of virtual address sll t7,t7,ENTRYHI_VPN2 // and t6,t6,0xff << ENTRYHI_PID // isolate current PID or t7,t7,t6 // merge PID with VPN2 of virtual address mtc0 t7,entryhi // set VPN2 and PID for probe mtc0 t1,entrylo0 // set first PTE value mtc0 t2,entrylo1 // set second PTE value mtc0 t3,index // set TB index value nop // fill tlbwi // write TB entry - 3 cycle hazzard subu t6,t4,1 // compute block size minus one and t7,t0,t6 // compute offset in block addu a2,a2,t6 // round up to next block addu a2,a2,t7 // nor t6,t6,zero // complement block size minus one and a2,a2,t6 // truncate length to even number beq zero,a2,30f // if eq, no blocks to purge and t8,t0,t6 // compute starting virtual address addu t9,t8,a2 // compute ending virtual address bne zero,v0,40f // if ne, second level cache present subu t9,t9,t4 // compute ending loop address // // Purge the primary instruction cache only. // 20: cache HIT_INVALIDATE_I,0(t8) // invalidate cache block bne t8,t9,20b // if ne, more blocks to invalidate addu t8,t8,t4 // compute next block address .set at .set reorder 30: ENABLE_INTERRUPTS(t5) // enable interrupts j ra // return // // Purge the primary and secondary instruction caches. // .set noreorder .set noat 40: cache HIT_INVALIDATE_SI,0(t8) // invalidate cache block bne t8,t9,40b // if ne, more blocks to invalidate addu t8,t8,t4 // compute next block address .set at .set reorder ENABLE_INTERRUPTS(t5) // enable interrupts j ra // return .end HalPurgeIcachePage SBTTL("Sweep Data Cache") //++ // // VOID // HalSweepDcache ( // VOID // ) // // Routine Description: // // This function sweeps (index/writeback/invalidate) the entire data cache. // // Arguments: // // None. // // Return Value: // // None. // //-- LEAF_ENTRY(HalSweepDcache) #if DBG lw t0,KeDcacheFlushCount // get address of dcache flush count lw t1,0(t0) // increment the count of flushes addu t1,t1,1 // sw t1,0(t0) // store result #endif lw t0,KiPcr + PcFirstLevelDcacheSize(zero) // get data cache size lw t1,KiPcr + PcFirstLevelDcacheFillSize(zero) // get block size li a0,KSEG0_BASE // set starting index value addu a1,a0,t0 // compute ending cache address subu a1,a1,t1 // compute ending block address // // Sweep the primary data cache. // .set noreorder .set noat 10: cache INDEX_WRITEBACK_INVALIDATE_D,0(a0) // writeback/invalidate on index #if defined(_MIPS_R4600) nop // fill cache INDEX_WRITEBACK_INVALIDATE_D,8192(a0) // writeback/invalidate on index #endif bne a0,a1,10b // if ne, more to invalidate addu a0,a0,t1 // compute address of next block .set at .set reorder lw t0,KiPcr + PcSecondLevelDcacheSize(zero) // get data cache size lw t1,KiPcr + PcSecondLevelDcacheFillSize(zero) // get block size beq zero,t1,30f // if eq, no second level cache li a0,KSEG0_BASE // set starting index value addu a1,a0,t0 // compute ending cache address subu a1,a1,t1 // compute ending block address // // Sweep the secondary data cache. // .set noreorder .set noat 20: cache INDEX_WRITEBACK_INVALIDATE_SD,0(a0) // writeback/invalidate on index bne a0,a1,20b // if ne, more to invalidate addu a0,a0,t1 // compute address of next block .set at .set reorder 30: j ra // return .end HalSweepDcache SBTTL("Sweep Data Cache Range") //++ // // VOID // HalSweepDcacheRange ( // IN PVOID BaseAddress, // IN ULONG Length // ) // // Routine Description: // // This function sweeps (index/writeback/invalidate) the specified range // of virtual addresses from the primary data cache. // // Arguments: // // BaseAddress (a0) - Supplies the base address of the range that is swept // from the data cache. // // Length (a1) - Supplies the length of the range that is swept from the // data cache. // // Return Value: // // None. // //-- LEAF_ENTRY(HalSweepDcacheRange) #if DBG lw t0,KeDcacheFlushCount // get address of dcache flush count lw t1,0(t0) // increment the count of flushes addu t1,t1,1 // sw t1,0(t0) // store result conditionally #endif and a0,a0,COLOR_MASK // isolate color and offset bits or a0,a0,KSEG0_BASE // convert to physical address lw t0,KiPcr + PcFirstLevelDcacheFillSize(zero) // get block size addu a1,a0,a1 // compute ending cache address subu a1,a1,t0 // compute ending block address // // Sweep the primary data cache. // .set noreorder .set noat 10: cache INDEX_WRITEBACK_INVALIDATE_D,0(a0) // writeback/invalidate on index #if defined(_MIPS_R4600) nop // fill cache INDEX_WRITEBACK_INVALIDATE_D,8192(a0) // writeback/invalidate on index #endif bne a0,a1,10b // if ne, more to invalidate addu a0,a0,t0 // compute address of next block .set at .set reorder j ra // return .end HalSweepDcacheRange SBTTL("Sweep Instruction Cache") //++ // // VOID // HalSweepIcache ( // VOID // ) // // Routine Description: // // This function sweeps (index/invalidate) the entire instruction cache. // // Arguments: // // None. // // Return Value: // // None. // //-- LEAF_ENTRY(HalSweepIcache) #if DBG lw t0,KeIcacheFlushCount // get address of icache flush count lw t1,0(t0) // increment the count of flushes addu t1,t1,1 // sw t1,0(t0) // store result #endif lw t0,KiPcr + PcSecondLevelIcacheSize(zero) // get instruction cache size lw t1,KiPcr + PcSecondLevelIcacheFillSize(zero) // get fill size beq zero,t1,20f // if eq, no second level cache li a0,KSEG0_BASE // set starting index value addu a1,a0,t0 // compute ending cache address subu a1,a1,t1 // compute ending block address // // Sweep the secondary instruction cache. // .set noreorder .set noat 10: cache INDEX_INVALIDATE_SI,0(a0) // invalidate cache line bne a0,a1,10b // if ne, more to invalidate addu a0,a0,t1 // compute address of next block .set at .set reorder 20: lw t0,KiPcr + PcFirstLevelIcacheSize(zero) // get instruction cache size lw t1,KiPcr + PcFirstLevelIcacheFillSize(zero) // get fill size li a0,KSEG0_BASE // set starting index value addu a1,a0,t0 // compute ending cache address subu a1,a1,t1 // compute ending block address // // Sweep the primary instruction cache. // #if defined(_MIPS_R4600) DISABLE_INTERRUPTS(t0) // disable interrupts #endif .set noreorder .set noat 30: cache INDEX_INVALIDATE_I,0(a0) // invalidate cache line #if defined(_MIPS_R4600) nop // fill cache INDEX_INVALIDATE_I,8192(a0) // writeback/invalidate on index #endif bne a0,a1,30b // if ne, more to invalidate addu a0,a0,t1 // compute address of next block .set at .set reorder #if defined(_MIPS_R4600) ENABLE_INTERRUPTS(t0) // enable interrupts #endif j ra // return .end HalSweepIcache SBTTL("Sweep Instruction Cache Range") //++ // // VOID // HalSweepIcacheRange ( // IN PVOID BaseAddress, // IN ULONG Length // ) // // Routine Description: // // This function sweeps (index/invalidate) the specified range of addresses // from the instruction cache. // // Arguments: // // BaseAddress (a0) - Supplies the base address of the range that is swept // from the instruction cache. // // Length (a1) - Supplies the length of the range that is swept from the // instruction cache. // // Return Value: // // None. // //-- LEAF_ENTRY(HalSweepIcacheRange) #if DBG lw t0,KeIcacheFlushCount // get address of icache flush count lw t1,0(t0) // increment the count of flushes addu t1,t1,1 // sw t1,0(t0) // store result #endif and a0,a0,COLOR_MASK // isolate color and offset bits or a0,a0,KSEG0_BASE // convert to physical address lw t0,KiPcr + PcFirstLevelIcacheFillSize(zero) // get fill size addu a1,a0,a1 // compute ending cache address subu a1,a1,t0 // compute ending block address // // Sweep the primary instruction cache. // #if defined(_MIPS_R4600) DISABLE_INTERRUPTS(t1) // disable interrupts #endif .set noreorder .set noat 10: cache INDEX_INVALIDATE_I,0(a0) // invalidate cache line #if defined(_MIPS_R4600) nop // fill cache INDEX_INVALIDATE_I,8192(a0) // writeback/invalidate on index #endif bne a0,a1,10b // if ne, more to invalidate addu a0,a0,t0 // compute address of next block .set at .set reorder #if defined(_MIPS_R4600) ENABLE_INTERRUPTS(t1) // enable interrupts #endif j ra // return .end HalSweepIcacheRange SBTTL("Zero Page") //++ // // VOID // HalZeroPage ( // IN PVOID NewColor, // IN PVOID OldColor, // IN ULONG PageFrame // ) // // Routine Description: // // This function zeros a page of memory. // // The algorithm used to zero a page is as follows: // // 1. Purge (hit/invalidate) the page from the instruction cache // using the old color iff the old color is not the same as // the new color. // // 2. Purge (hit/invalidate) the page from the data cache using // the old color iff the old color is not the same as the new // color. // // 3. Create (create/dirty/exclusive) the page in the data cache // using the new color. // // 4. Write zeros to the page using the new color. // // Arguments: // // NewColor (a0) - Supplies the page aligned virtual address of the // new color of the page that is zeroed. // // OldColor (a1) - Supplies the page aligned virtual address of the // old color of the page that is zeroed. // // PageFrame (a2) - Supplies the page frame number of the page that // is zeroed. // // Return Value: // // None. // //-- .struct 0 .space 3 * 4 // fill ZpRa: .space 4 // saved return address ZpFrameLength: // length of stack frame ZpA0: .space 4 // (a0) ZpA1: .space 4 // (a1) ZpA2: .space 4 // (a2) ZpA3: .space 4 // (a3) NESTED_ENTRY(HalZeroPage, ZpFrameLength, zero) subu sp,sp,ZpFrameLength // allocate stack frame sw ra,ZpRa(sp) // save return address PROLOGUE_END and a0,a0,COLOR_BITS // isolate new color bits and a1,a1,COLOR_BITS // isolate old color bits sw a0,ZpA0(sp) // save new color bits sw a2,ZpA2(sp) // save page frame // // If the old page color is not equal to the new page color, then change // the color of the page. // beq a0,a1,10f // if eq, colors match jal KeChangeColorPage // chagne page color // // Create dirty exclusive cache blocks and zero the data. // 10: lw a3,ZpA0(sp) // get new color bits lw a1,ZpA2(sp) // get page frame number .set noreorder .set noat lw v0,KiPcr + PcAlignedCachePolicy(zero) // get cache polciy li t0,FLUSH_BASE // get base flush address or t0,t0,a3 // compute new color virtual address sll t1,a1,ENTRYLO_PFN // shift page frame into position or t1,t1,PROTECTION_BITS // merge protection bits or t1,t1,v0 // merge cache policy and a3,a3,0x1000 // isolate TB entry index beql zero,a3,20f // if eq, first entry move t2,zero // set second page table entry move t2,t1 // set second page table entry move t1,zero // set first page table entry 20: mfc0 t3,wired // get TB entry index lw t4,KiPcr + PcFirstLevelDcacheFillSize(zero) // get 1st fill size lw v0,KiPcr + PcSecondLevelDcacheFillSize(zero) // get 2nd fill size .set at .set reorder DISABLE_INTERRUPTS(t5) // disable interrupts .set noreorder .set noat mfc0 t6,entryhi // get current PID and VPN2 srl t7,t0,ENTRYHI_VPN2 // isolate VPN2 of virtual address sll t7,t7,ENTRYHI_VPN2 // and t6,t6,0xff << ENTRYHI_PID // isolate current PID or t7,t7,t6 // merge PID with VPN2 of virtual address mtc0 t7,entryhi // set VPN2 and PID for probe mtc0 t1,entrylo0 // set first PTE value mtc0 t2,entrylo1 // set second PTE value mtc0 t3,index // set TB index value nop // fill tlbwi // write TB entry - 3 cycle hazzard addu t9,t0,PAGE_SIZE // compute ending address of block dmtc1 zero,f0 // set write pattern bne zero,v0,50f // if ne, second level cache present and t8,t4,0x10 // test if 16-byte cache block // // Zero page in primary data cache only. // #if defined(_DUO_) 30: sdc1 f0,0(t0) // zero 64-byte block sdc1 f0,8(t0) // sdc1 f0,16(t0) // sdc1 f0,24(t0) // sdc1 f0,32(t0) // sdc1 f0,40(t0) // sdc1 f0,48(t0) // addu t0,t0,64 // advance to next 64-byte block bne t0,t9,30b // if ne, more to zero sdc1 f0,-8(t0) // #else 30: cache CREATE_DIRTY_EXCLUSIVE_D,0(t0) // create cache block addu t0,t0,t4 // compute next block address bne zero,t8,40f // if ne, 16-byte cache line sdc1 f0,-16(t0) // sdc1 f0,-24(t0) // zero 16 bytes sdc1 f0,-32(t0) // 40: bne t0,t9,30b // if ne, more blocks to zero sdc1 f0,-8(t0) // zero 16 bytes #endif .set at .set reorder ENABLE_INTERRUPTS(t5) // enable interrupts lw ra,ZpRa(sp) // get return address addu sp,sp,ZpFrameLength // deallocate stack frame j ra // return // // Zero page in primary and secondary data caches. // .set noreorder .set noat #if defined(_DUO_) 50: sdc1 f0,0(t0) // zero 64-byte block sdc1 f0,8(t0) // sdc1 f0,16(t0) // sdc1 f0,24(t0) // sdc1 f0,32(t0) // sdc1 f0,40(t0) // sdc1 f0,48(t0) // addu t0,t0,64 // advance to next 64-byte block bne t0,t9,50b // if ne, more to zero sdc1 f0,-8(t0) // #else 50: cache CREATE_DIRTY_EXCLUSIVE_SD,0(t0) // create secondary cache block addu v1,v0,t0 // compute ending primary block address 60: addu t0,t0,t4 // compute next block address bne zero,t8,70f // if ne, 16-byte primary cache line sdc1 f0,-16(t0) // sdc1 f0,-24(t0) // zero 16 bytes sdc1 f0,-32(t0) // 70: bne t0,v1,60b // if ne, more primary blocks to zero sdc1 f0,-8(t0) // zero 16 bytes bne t0,t9,50b // if ne, more secondary blocks to zero nop // fill #endif .set at .set reorder ENABLE_INTERRUPTS(t5) // enable interrupts lw ra,ZpRa(sp) // get return address addu sp,sp,ZpFrameLength // deallocate stack frame j ra // return .end HalZeroPage