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//#pragma comment(exestr, "$Header: /usr4/winnt/SOURCES/halpcims/src/hal/halsnipm/mips/RCS/orcache.s,v 1.3 1996/02/23 17:55:12 pierre Exp $")
// TITLE("Cache Flush")
//++
//
// Copyright (c) 1991-1993 Microsoft Corporation
//
// Module Name:
//
// orcache.s
//
// Abstract:
//
// This module implements the code necessary for cache operations on
// R4600 orion Machines.
//
// Environment:
//
// Kernel mode only.
//
//--
#include "halmips.h"
#include "SNIdef.h"
#define ORION_REPLACE 0x17c00000
//
// some bitmap defines to display cache activities via the LED's
// in the SNI RM machines
//
#define SWEEP_DCACHE 0xc0 // 1100 0000
#define FLUSH_DCACHE_PAGE 0x80 // 1000 0000
#define PURGE_DCACHE_PAGE 0x40 // 0100 0000
#define ZERO_PAGE 0x0c // 0000 1100
#define SWEEP_ICACHE 0x30 // 0011 0000
#define PURGE_ICACHE_PAGE 0x10 // 0001 0000
//
// 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("Flush Data Cache Page")
//++
//
// VOID
// HalpFlushDcachePageOrion (
// IN PVOID Color,
// IN ULONG PageFrame,
// IN ULONG Length
// )
//
// Routine Description:
//
// This function flushes (cache replace) up to a page of data
// from the secondary data cache. (primary cache is already processed)
//
// 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(HalpFlushDcachePageOrion)
#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
15: DISABLE_INTERRUPTS(t5) // disable interrupts
.set noreorder
.set noat
//
// Flush the secondary data caches => cache replace.
//
.set noreorder
.set noat
40: and a0,a0,PAGE_SIZE -1 // PageOffset
sll t7,a1,PAGE_SHIFT // physical address
lw t4,KiPcr + PcSecondLevelDcacheFillSize(zero) // get 2nd fill size
or t0,t7,a0 // physical address + offset
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,a2,60f // if eq, no blocks to flush
and t8,t0,t6 // compute starting virtual address
addu t9,t8,a2 // compute ending virtual address
subu t9,t9,t4 // compute ending loop address
li a3,ORION_REPLACE // get base flush address
lw t0,KiPcr + PcSecondLevelDcacheSize(zero) // get cache size
add t0,t0,-1 // mask of the cache size
.set noreorder
.set noat
50: and t7,t8,t0 // offset
addu t7,t7,a3 // physical address + offset
lw zero,0(t7) // load Cache -> Write back old Data
bne t8,t9,50b // if ne, more blocks to invalidate
addu t8,t8,t4 // compute next block address (+Linesize)
60: ENABLE_INTERRUPTS(t5) // enable interrupts
j ra // return
.end HalpFlushDcachePageOrion
SBTTL("Purge Instruction Cache Page")
//++
//
// VOID
// HalpPurgeIcachePageOrion (
// IN PVOID Color,
// IN ULONG PageFrame,
// IN ULONG Length
// )
//
// Routine Description:
//
// This function purges (hit/invalidate) up to a page of 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(HalpPurgeIcachePageOrion)
#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
15: DISABLE_INTERRUPTS(t5) // disable interrupts
.set noreorder
.set noat
//
// Flush the secondary data caches => cache replace.
//
.set noreorder
.set noat
40: and a0,a0,PAGE_SIZE -1 // PageOffset
sll t7,a1,PAGE_SHIFT // physical address
lw t4,KiPcr + PcSecondLevelIcacheFillSize(zero) // get 2nd fill size
beq t4,zero,60f
or t0,t7,a0 // physical address + offset
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,a2,60f // if eq, no blocks to flush
and t8,t0,t6 // compute starting virtual address
addu t9,t8,a2 // compute ending virtual address
subu t9,t9,t4 // compute ending loop address
li a3,ORION_REPLACE // get base flush address
lw t0,KiPcr + PcSecondLevelIcacheSize(zero) // get cache size
add t0,t0,-1 // mask of the cache size
50: and t7,t8,t0 // offset
addu t7,t7,a3 // physical address + offset
lw zero,0(t7) // load Cache -> Write back old Data
bne t8,t9,50b // if ne, more blocks to invalidate
addu t8,t8,t4 // compute next block address (+Linesize)
60: ENABLE_INTERRUPTS(t5) // enable interrupts
j ra // return
.end HalpPurgeIcachePageOrion
SBTTL("Sweep Data Cache")
//++
//
// VOID
// HalpSweepDcacheOrion (
// VOID
// )
//
// Routine Description:
//
// This function sweeps (index/writeback/invalidate) the entire data cache.
//
// Arguments:
//
// None.
//
// Return Value:
//
// None.
//
//--
LEAF_ENTRY(HalpSweepDcacheOrion)
#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 at
.set reorder
DISABLE_INTERRUPTS(t3) // disable interrupts
.set noreorder
.set noat
//
// Sweep the primary data cache.
//
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
//
// the size is configured on SNI machines as 16KB
// we invalidate in both sets - so divide the configured size by 2
//
srl t0,t0,1
addu a1,a0,t0 // compute ending cache address
subu a1,a1,t1 // compute ending block address
10:
cache INDEX_WRITEBACK_INVALIDATE_D,0(a0) // writeback/invalidate on index
cache INDEX_WRITEBACK_INVALIDATE_D,8192(a0)
bne a0,a1,10b // if ne, more to invalidate
addu a0,a0,t1 // compute address of next block
//
// sweep secondary cache
//
lw t0,KiPcr + PcSecondLevelDcacheSize(zero) // get data cache size
lw t1,KiPcr + PcSecondLevelDcacheFillSize(zero) // get block size
li a0,ORION_REPLACE // starting address
addu a1,a0,t0 // compute ending cache address
subu a1,a1,t1 // compute ending block address
25:
lw zero,0(a0)
bne a0,a1,25b // if ne, more to invalidate
addu a0,a0,t1 // compute address of next block
ENABLE_INTERRUPTS(t3) // enable interrupts
.set at
.set reorder
j ra // return
.end HalpSweepDcacheMulti
SBTTL("Sweep Instruction Cache")
//++
//
// VOID
// HalpSweepIcacheOrion (
// VOID
// )
//
// Routine Description:
//
// This function sweeps (index/invalidate) the entire instruction cache.
//
// Arguments:
//
// None.
//
// Return Value:
//
// None.
//
//--
LEAF_ENTRY(HalpSweepIcacheOrion)
#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
//
// Sweep the secondary instruction cache.
//
.set noreorder
.set noat
DISABLE_INTERRUPTS(t3) // disable interrupts
.set noreorder
.set noat
//
// sweep secondary cache
//
lw t0,KiPcr + PcSecondLevelIcacheSize(zero) // get instruction cache size
lw t1,KiPcr + PcSecondLevelIcacheFillSize(zero) // get fill size
beq zero,t0,20f // if eq, no second level cache
li a0,ORION_REPLACE // set starting index value
addu a1,a0,t0 // compute ending cache address
subu a1,a1,t1 // compute ending block address
10: lw zero,0(a0)
bne a0,a1,10b // if ne, more to invalidate
addu a0,a0,t1 // compute address of next block
//
// Sweep the primary instruction cache.
//
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
//
// the size is configured on SNI machines as 16KB
// we invalidate in both sets - so divide the configured size by 2
//
srl t0,t0,1
addu a1,a0,t0 // compute ending cache address
subu a1,a1,t1 // compute ending block address
//
// Sweep the primary instruction cache.
//
30: cache INDEX_INVALIDATE_I,0(a0) // invalidate cache line
cache INDEX_INVALIDATE_I,8192(a0)
bne a0,a1,30b // if ne, more to invalidate
addu a0,a0,t1 // compute address of next block
.set at
.set reorder
20: ENABLE_INTERRUPTS(t3) // enable interrupts
.set at
.set reorder
j ra // return
.end HalpSweepIcacheOrion
SBTTL("Zero Page")
//++
//
// VOID
// HalpZeroPageOrion (
// 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(HalpZeroPageOrion, 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 a1,ZpA1(sp) // save old 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
and t8,t4,0x10 // test if 16-byte cache block
//
// Zero page in primary and secondary data caches.
//
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) //
.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 HalpZeroPageOrion
|