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-rw-r--r--arch/ia64/kernel/head.S996
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diff --git a/arch/ia64/kernel/head.S b/arch/ia64/kernel/head.S
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+/*
+ * Here is where the ball gets rolling as far as the kernel is concerned.
+ * When control is transferred to _start, the bootload has already
+ * loaded us to the correct address. All that's left to do here is
+ * to set up the kernel's global pointer and jump to the kernel
+ * entry point.
+ *
+ * Copyright (C) 1998-2001, 2003, 2005 Hewlett-Packard Co
+ * David Mosberger-Tang <davidm@hpl.hp.com>
+ * Stephane Eranian <eranian@hpl.hp.com>
+ * Copyright (C) 1999 VA Linux Systems
+ * Copyright (C) 1999 Walt Drummond <drummond@valinux.com>
+ * Copyright (C) 1999 Intel Corp.
+ * Copyright (C) 1999 Asit Mallick <Asit.K.Mallick@intel.com>
+ * Copyright (C) 1999 Don Dugger <Don.Dugger@intel.com>
+ * Copyright (C) 2002 Fenghua Yu <fenghua.yu@intel.com>
+ * -Optimize __ia64_save_fpu() and __ia64_load_fpu() for Itanium 2.
+ */
+
+#include <linux/config.h>
+
+#include <asm/asmmacro.h>
+#include <asm/fpu.h>
+#include <asm/kregs.h>
+#include <asm/mmu_context.h>
+#include <asm/offsets.h>
+#include <asm/pal.h>
+#include <asm/pgtable.h>
+#include <asm/processor.h>
+#include <asm/ptrace.h>
+#include <asm/system.h>
+
+ .section __special_page_section,"ax"
+
+ .global empty_zero_page
+empty_zero_page:
+ .skip PAGE_SIZE
+
+ .global swapper_pg_dir
+swapper_pg_dir:
+ .skip PAGE_SIZE
+
+ .rodata
+halt_msg:
+ stringz "Halting kernel\n"
+
+ .text
+
+ .global start_ap
+
+ /*
+ * Start the kernel. When the bootloader passes control to _start(), r28
+ * points to the address of the boot parameter area. Execution reaches
+ * here in physical mode.
+ */
+GLOBAL_ENTRY(_start)
+start_ap:
+ .prologue
+ .save rp, r0 // terminate unwind chain with a NULL rp
+ .body
+
+ rsm psr.i | psr.ic
+ ;;
+ srlz.i
+ ;;
+ /*
+ * Initialize kernel region registers:
+ * rr[0]: VHPT enabled, page size = PAGE_SHIFT
+ * rr[1]: VHPT enabled, page size = PAGE_SHIFT
+ * rr[2]: VHPT enabled, page size = PAGE_SHIFT
+ * rr[3]: VHPT enabled, page size = PAGE_SHIFT
+ * rr[4]: VHPT enabled, page size = PAGE_SHIFT
+ * rr[5]: VHPT enabled, page size = PAGE_SHIFT
+ * rr[6]: VHPT disabled, page size = IA64_GRANULE_SHIFT
+ * rr[7]: VHPT disabled, page size = IA64_GRANULE_SHIFT
+ * We initialize all of them to prevent inadvertently assuming
+ * something about the state of address translation early in boot.
+ */
+ mov r6=((ia64_rid(IA64_REGION_ID_KERNEL, (0<<61)) << 8) | (PAGE_SHIFT << 2) | 1)
+ movl r7=(0<<61)
+ mov r8=((ia64_rid(IA64_REGION_ID_KERNEL, (1<<61)) << 8) | (PAGE_SHIFT << 2) | 1)
+ movl r9=(1<<61)
+ mov r10=((ia64_rid(IA64_REGION_ID_KERNEL, (2<<61)) << 8) | (PAGE_SHIFT << 2) | 1)
+ movl r11=(2<<61)
+ mov r12=((ia64_rid(IA64_REGION_ID_KERNEL, (3<<61)) << 8) | (PAGE_SHIFT << 2) | 1)
+ movl r13=(3<<61)
+ mov r14=((ia64_rid(IA64_REGION_ID_KERNEL, (4<<61)) << 8) | (PAGE_SHIFT << 2) | 1)
+ movl r15=(4<<61)
+ mov r16=((ia64_rid(IA64_REGION_ID_KERNEL, (5<<61)) << 8) | (PAGE_SHIFT << 2) | 1)
+ movl r17=(5<<61)
+ mov r18=((ia64_rid(IA64_REGION_ID_KERNEL, (6<<61)) << 8) | (IA64_GRANULE_SHIFT << 2))
+ movl r19=(6<<61)
+ mov r20=((ia64_rid(IA64_REGION_ID_KERNEL, (7<<61)) << 8) | (IA64_GRANULE_SHIFT << 2))
+ movl r21=(7<<61)
+ ;;
+ mov rr[r7]=r6
+ mov rr[r9]=r8
+ mov rr[r11]=r10
+ mov rr[r13]=r12
+ mov rr[r15]=r14
+ mov rr[r17]=r16
+ mov rr[r19]=r18
+ mov rr[r21]=r20
+ ;;
+ /*
+ * Now pin mappings into the TLB for kernel text and data
+ */
+ mov r18=KERNEL_TR_PAGE_SHIFT<<2
+ movl r17=KERNEL_START
+ ;;
+ mov cr.itir=r18
+ mov cr.ifa=r17
+ mov r16=IA64_TR_KERNEL
+ mov r3=ip
+ movl r18=PAGE_KERNEL
+ ;;
+ dep r2=0,r3,0,KERNEL_TR_PAGE_SHIFT
+ ;;
+ or r18=r2,r18
+ ;;
+ srlz.i
+ ;;
+ itr.i itr[r16]=r18
+ ;;
+ itr.d dtr[r16]=r18
+ ;;
+ srlz.i
+
+ /*
+ * Switch into virtual mode:
+ */
+ movl r16=(IA64_PSR_IT|IA64_PSR_IC|IA64_PSR_DT|IA64_PSR_RT|IA64_PSR_DFH|IA64_PSR_BN \
+ |IA64_PSR_DI)
+ ;;
+ mov cr.ipsr=r16
+ movl r17=1f
+ ;;
+ mov cr.iip=r17
+ mov cr.ifs=r0
+ ;;
+ rfi
+ ;;
+1: // now we are in virtual mode
+
+ // set IVT entry point---can't access I/O ports without it
+ movl r3=ia64_ivt
+ ;;
+ mov cr.iva=r3
+ movl r2=FPSR_DEFAULT
+ ;;
+ srlz.i
+ movl gp=__gp
+
+ mov ar.fpsr=r2
+ ;;
+
+#define isAP p2 // are we an Application Processor?
+#define isBP p3 // are we the Bootstrap Processor?
+
+#ifdef CONFIG_SMP
+ /*
+ * Find the init_task for the currently booting CPU. At poweron, and in
+ * UP mode, task_for_booting_cpu is NULL.
+ */
+ movl r3=task_for_booting_cpu
+ ;;
+ ld8 r3=[r3]
+ movl r2=init_task
+ ;;
+ cmp.eq isBP,isAP=r3,r0
+ ;;
+(isAP) mov r2=r3
+#else
+ movl r2=init_task
+ cmp.eq isBP,isAP=r0,r0
+#endif
+ ;;
+ tpa r3=r2 // r3 == phys addr of task struct
+ mov r16=-1
+(isBP) br.cond.dpnt .load_current // BP stack is on region 5 --- no need to map it
+
+ // load mapping for stack (virtaddr in r2, physaddr in r3)
+ rsm psr.ic
+ movl r17=PAGE_KERNEL
+ ;;
+ srlz.d
+ dep r18=0,r3,0,12
+ ;;
+ or r18=r17,r18
+ dep r2=-1,r3,61,3 // IMVA of task
+ ;;
+ mov r17=rr[r2]
+ shr.u r16=r3,IA64_GRANULE_SHIFT
+ ;;
+ dep r17=0,r17,8,24
+ ;;
+ mov cr.itir=r17
+ mov cr.ifa=r2
+
+ mov r19=IA64_TR_CURRENT_STACK
+ ;;
+ itr.d dtr[r19]=r18
+ ;;
+ ssm psr.ic
+ srlz.d
+ ;;
+
+.load_current:
+ // load the "current" pointer (r13) and ar.k6 with the current task
+ mov IA64_KR(CURRENT)=r2 // virtual address
+ mov IA64_KR(CURRENT_STACK)=r16
+ mov r13=r2
+ /*
+ * Reserve space at the top of the stack for "struct pt_regs". Kernel threads
+ * don't store interesting values in that structure, but the space still needs
+ * to be there because time-critical stuff such as the context switching can
+ * be implemented more efficiently (for example, __switch_to()
+ * always sets the psr.dfh bit of the task it is switching to).
+ */
+ addl r12=IA64_STK_OFFSET-IA64_PT_REGS_SIZE-16,r2
+ addl r2=IA64_RBS_OFFSET,r2 // initialize the RSE
+ mov ar.rsc=0 // place RSE in enforced lazy mode
+ ;;
+ loadrs // clear the dirty partition
+ ;;
+ mov ar.bspstore=r2 // establish the new RSE stack
+ ;;
+ mov ar.rsc=0x3 // place RSE in eager mode
+
+(isBP) dep r28=-1,r28,61,3 // make address virtual
+(isBP) movl r2=ia64_boot_param
+ ;;
+(isBP) st8 [r2]=r28 // save the address of the boot param area passed by the bootloader
+
+#ifdef CONFIG_SMP
+(isAP) br.call.sptk.many rp=start_secondary
+.ret0:
+(isAP) br.cond.sptk self
+#endif
+
+ // This is executed by the bootstrap processor (bsp) only:
+
+#ifdef CONFIG_IA64_FW_EMU
+ // initialize PAL & SAL emulator:
+ br.call.sptk.many rp=sys_fw_init
+.ret1:
+#endif
+ br.call.sptk.many rp=start_kernel
+.ret2: addl r3=@ltoff(halt_msg),gp
+ ;;
+ alloc r2=ar.pfs,8,0,2,0
+ ;;
+ ld8 out0=[r3]
+ br.call.sptk.many b0=console_print
+
+self: hint @pause
+ br.sptk.many self // endless loop
+END(_start)
+
+GLOBAL_ENTRY(ia64_save_debug_regs)
+ alloc r16=ar.pfs,1,0,0,0
+ mov r20=ar.lc // preserve ar.lc
+ mov ar.lc=IA64_NUM_DBG_REGS-1
+ mov r18=0
+ add r19=IA64_NUM_DBG_REGS*8,in0
+ ;;
+1: mov r16=dbr[r18]
+#ifdef CONFIG_ITANIUM
+ ;;
+ srlz.d
+#endif
+ mov r17=ibr[r18]
+ add r18=1,r18
+ ;;
+ st8.nta [in0]=r16,8
+ st8.nta [r19]=r17,8
+ br.cloop.sptk.many 1b
+ ;;
+ mov ar.lc=r20 // restore ar.lc
+ br.ret.sptk.many rp
+END(ia64_save_debug_regs)
+
+GLOBAL_ENTRY(ia64_load_debug_regs)
+ alloc r16=ar.pfs,1,0,0,0
+ lfetch.nta [in0]
+ mov r20=ar.lc // preserve ar.lc
+ add r19=IA64_NUM_DBG_REGS*8,in0
+ mov ar.lc=IA64_NUM_DBG_REGS-1
+ mov r18=-1
+ ;;
+1: ld8.nta r16=[in0],8
+ ld8.nta r17=[r19],8
+ add r18=1,r18
+ ;;
+ mov dbr[r18]=r16
+#ifdef CONFIG_ITANIUM
+ ;;
+ srlz.d // Errata 132 (NoFix status)
+#endif
+ mov ibr[r18]=r17
+ br.cloop.sptk.many 1b
+ ;;
+ mov ar.lc=r20 // restore ar.lc
+ br.ret.sptk.many rp
+END(ia64_load_debug_regs)
+
+GLOBAL_ENTRY(__ia64_save_fpu)
+ alloc r2=ar.pfs,1,4,0,0
+ adds loc0=96*16-16,in0
+ adds loc1=96*16-16-128,in0
+ ;;
+ stf.spill.nta [loc0]=f127,-256
+ stf.spill.nta [loc1]=f119,-256
+ ;;
+ stf.spill.nta [loc0]=f111,-256
+ stf.spill.nta [loc1]=f103,-256
+ ;;
+ stf.spill.nta [loc0]=f95,-256
+ stf.spill.nta [loc1]=f87,-256
+ ;;
+ stf.spill.nta [loc0]=f79,-256
+ stf.spill.nta [loc1]=f71,-256
+ ;;
+ stf.spill.nta [loc0]=f63,-256
+ stf.spill.nta [loc1]=f55,-256
+ adds loc2=96*16-32,in0
+ ;;
+ stf.spill.nta [loc0]=f47,-256
+ stf.spill.nta [loc1]=f39,-256
+ adds loc3=96*16-32-128,in0
+ ;;
+ stf.spill.nta [loc2]=f126,-256
+ stf.spill.nta [loc3]=f118,-256
+ ;;
+ stf.spill.nta [loc2]=f110,-256
+ stf.spill.nta [loc3]=f102,-256
+ ;;
+ stf.spill.nta [loc2]=f94,-256
+ stf.spill.nta [loc3]=f86,-256
+ ;;
+ stf.spill.nta [loc2]=f78,-256
+ stf.spill.nta [loc3]=f70,-256
+ ;;
+ stf.spill.nta [loc2]=f62,-256
+ stf.spill.nta [loc3]=f54,-256
+ adds loc0=96*16-48,in0
+ ;;
+ stf.spill.nta [loc2]=f46,-256
+ stf.spill.nta [loc3]=f38,-256
+ adds loc1=96*16-48-128,in0
+ ;;
+ stf.spill.nta [loc0]=f125,-256
+ stf.spill.nta [loc1]=f117,-256
+ ;;
+ stf.spill.nta [loc0]=f109,-256
+ stf.spill.nta [loc1]=f101,-256
+ ;;
+ stf.spill.nta [loc0]=f93,-256
+ stf.spill.nta [loc1]=f85,-256
+ ;;
+ stf.spill.nta [loc0]=f77,-256
+ stf.spill.nta [loc1]=f69,-256
+ ;;
+ stf.spill.nta [loc0]=f61,-256
+ stf.spill.nta [loc1]=f53,-256
+ adds loc2=96*16-64,in0
+ ;;
+ stf.spill.nta [loc0]=f45,-256
+ stf.spill.nta [loc1]=f37,-256
+ adds loc3=96*16-64-128,in0
+ ;;
+ stf.spill.nta [loc2]=f124,-256
+ stf.spill.nta [loc3]=f116,-256
+ ;;
+ stf.spill.nta [loc2]=f108,-256
+ stf.spill.nta [loc3]=f100,-256
+ ;;
+ stf.spill.nta [loc2]=f92,-256
+ stf.spill.nta [loc3]=f84,-256
+ ;;
+ stf.spill.nta [loc2]=f76,-256
+ stf.spill.nta [loc3]=f68,-256
+ ;;
+ stf.spill.nta [loc2]=f60,-256
+ stf.spill.nta [loc3]=f52,-256
+ adds loc0=96*16-80,in0
+ ;;
+ stf.spill.nta [loc2]=f44,-256
+ stf.spill.nta [loc3]=f36,-256
+ adds loc1=96*16-80-128,in0
+ ;;
+ stf.spill.nta [loc0]=f123,-256
+ stf.spill.nta [loc1]=f115,-256
+ ;;
+ stf.spill.nta [loc0]=f107,-256
+ stf.spill.nta [loc1]=f99,-256
+ ;;
+ stf.spill.nta [loc0]=f91,-256
+ stf.spill.nta [loc1]=f83,-256
+ ;;
+ stf.spill.nta [loc0]=f75,-256
+ stf.spill.nta [loc1]=f67,-256
+ ;;
+ stf.spill.nta [loc0]=f59,-256
+ stf.spill.nta [loc1]=f51,-256
+ adds loc2=96*16-96,in0
+ ;;
+ stf.spill.nta [loc0]=f43,-256
+ stf.spill.nta [loc1]=f35,-256
+ adds loc3=96*16-96-128,in0
+ ;;
+ stf.spill.nta [loc2]=f122,-256
+ stf.spill.nta [loc3]=f114,-256
+ ;;
+ stf.spill.nta [loc2]=f106,-256
+ stf.spill.nta [loc3]=f98,-256
+ ;;
+ stf.spill.nta [loc2]=f90,-256
+ stf.spill.nta [loc3]=f82,-256
+ ;;
+ stf.spill.nta [loc2]=f74,-256
+ stf.spill.nta [loc3]=f66,-256
+ ;;
+ stf.spill.nta [loc2]=f58,-256
+ stf.spill.nta [loc3]=f50,-256
+ adds loc0=96*16-112,in0
+ ;;
+ stf.spill.nta [loc2]=f42,-256
+ stf.spill.nta [loc3]=f34,-256
+ adds loc1=96*16-112-128,in0
+ ;;
+ stf.spill.nta [loc0]=f121,-256
+ stf.spill.nta [loc1]=f113,-256
+ ;;
+ stf.spill.nta [loc0]=f105,-256
+ stf.spill.nta [loc1]=f97,-256
+ ;;
+ stf.spill.nta [loc0]=f89,-256
+ stf.spill.nta [loc1]=f81,-256
+ ;;
+ stf.spill.nta [loc0]=f73,-256
+ stf.spill.nta [loc1]=f65,-256
+ ;;
+ stf.spill.nta [loc0]=f57,-256
+ stf.spill.nta [loc1]=f49,-256
+ adds loc2=96*16-128,in0
+ ;;
+ stf.spill.nta [loc0]=f41,-256
+ stf.spill.nta [loc1]=f33,-256
+ adds loc3=96*16-128-128,in0
+ ;;
+ stf.spill.nta [loc2]=f120,-256
+ stf.spill.nta [loc3]=f112,-256
+ ;;
+ stf.spill.nta [loc2]=f104,-256
+ stf.spill.nta [loc3]=f96,-256
+ ;;
+ stf.spill.nta [loc2]=f88,-256
+ stf.spill.nta [loc3]=f80,-256
+ ;;
+ stf.spill.nta [loc2]=f72,-256
+ stf.spill.nta [loc3]=f64,-256
+ ;;
+ stf.spill.nta [loc2]=f56,-256
+ stf.spill.nta [loc3]=f48,-256
+ ;;
+ stf.spill.nta [loc2]=f40
+ stf.spill.nta [loc3]=f32
+ br.ret.sptk.many rp
+END(__ia64_save_fpu)
+
+GLOBAL_ENTRY(__ia64_load_fpu)
+ alloc r2=ar.pfs,1,2,0,0
+ adds r3=128,in0
+ adds r14=256,in0
+ adds r15=384,in0
+ mov loc0=512
+ mov loc1=-1024+16
+ ;;
+ ldf.fill.nta f32=[in0],loc0
+ ldf.fill.nta f40=[ r3],loc0
+ ldf.fill.nta f48=[r14],loc0
+ ldf.fill.nta f56=[r15],loc0
+ ;;
+ ldf.fill.nta f64=[in0],loc0
+ ldf.fill.nta f72=[ r3],loc0
+ ldf.fill.nta f80=[r14],loc0
+ ldf.fill.nta f88=[r15],loc0
+ ;;
+ ldf.fill.nta f96=[in0],loc1
+ ldf.fill.nta f104=[ r3],loc1
+ ldf.fill.nta f112=[r14],loc1
+ ldf.fill.nta f120=[r15],loc1
+ ;;
+ ldf.fill.nta f33=[in0],loc0
+ ldf.fill.nta f41=[ r3],loc0
+ ldf.fill.nta f49=[r14],loc0
+ ldf.fill.nta f57=[r15],loc0
+ ;;
+ ldf.fill.nta f65=[in0],loc0
+ ldf.fill.nta f73=[ r3],loc0
+ ldf.fill.nta f81=[r14],loc0
+ ldf.fill.nta f89=[r15],loc0
+ ;;
+ ldf.fill.nta f97=[in0],loc1
+ ldf.fill.nta f105=[ r3],loc1
+ ldf.fill.nta f113=[r14],loc1
+ ldf.fill.nta f121=[r15],loc1
+ ;;
+ ldf.fill.nta f34=[in0],loc0
+ ldf.fill.nta f42=[ r3],loc0
+ ldf.fill.nta f50=[r14],loc0
+ ldf.fill.nta f58=[r15],loc0
+ ;;
+ ldf.fill.nta f66=[in0],loc0
+ ldf.fill.nta f74=[ r3],loc0
+ ldf.fill.nta f82=[r14],loc0
+ ldf.fill.nta f90=[r15],loc0
+ ;;
+ ldf.fill.nta f98=[in0],loc1
+ ldf.fill.nta f106=[ r3],loc1
+ ldf.fill.nta f114=[r14],loc1
+ ldf.fill.nta f122=[r15],loc1
+ ;;
+ ldf.fill.nta f35=[in0],loc0
+ ldf.fill.nta f43=[ r3],loc0
+ ldf.fill.nta f51=[r14],loc0
+ ldf.fill.nta f59=[r15],loc0
+ ;;
+ ldf.fill.nta f67=[in0],loc0
+ ldf.fill.nta f75=[ r3],loc0
+ ldf.fill.nta f83=[r14],loc0
+ ldf.fill.nta f91=[r15],loc0
+ ;;
+ ldf.fill.nta f99=[in0],loc1
+ ldf.fill.nta f107=[ r3],loc1
+ ldf.fill.nta f115=[r14],loc1
+ ldf.fill.nta f123=[r15],loc1
+ ;;
+ ldf.fill.nta f36=[in0],loc0
+ ldf.fill.nta f44=[ r3],loc0
+ ldf.fill.nta f52=[r14],loc0
+ ldf.fill.nta f60=[r15],loc0
+ ;;
+ ldf.fill.nta f68=[in0],loc0
+ ldf.fill.nta f76=[ r3],loc0
+ ldf.fill.nta f84=[r14],loc0
+ ldf.fill.nta f92=[r15],loc0
+ ;;
+ ldf.fill.nta f100=[in0],loc1
+ ldf.fill.nta f108=[ r3],loc1
+ ldf.fill.nta f116=[r14],loc1
+ ldf.fill.nta f124=[r15],loc1
+ ;;
+ ldf.fill.nta f37=[in0],loc0
+ ldf.fill.nta f45=[ r3],loc0
+ ldf.fill.nta f53=[r14],loc0
+ ldf.fill.nta f61=[r15],loc0
+ ;;
+ ldf.fill.nta f69=[in0],loc0
+ ldf.fill.nta f77=[ r3],loc0
+ ldf.fill.nta f85=[r14],loc0
+ ldf.fill.nta f93=[r15],loc0
+ ;;
+ ldf.fill.nta f101=[in0],loc1
+ ldf.fill.nta f109=[ r3],loc1
+ ldf.fill.nta f117=[r14],loc1
+ ldf.fill.nta f125=[r15],loc1
+ ;;
+ ldf.fill.nta f38 =[in0],loc0
+ ldf.fill.nta f46 =[ r3],loc0
+ ldf.fill.nta f54 =[r14],loc0
+ ldf.fill.nta f62 =[r15],loc0
+ ;;
+ ldf.fill.nta f70 =[in0],loc0
+ ldf.fill.nta f78 =[ r3],loc0
+ ldf.fill.nta f86 =[r14],loc0
+ ldf.fill.nta f94 =[r15],loc0
+ ;;
+ ldf.fill.nta f102=[in0],loc1
+ ldf.fill.nta f110=[ r3],loc1
+ ldf.fill.nta f118=[r14],loc1
+ ldf.fill.nta f126=[r15],loc1
+ ;;
+ ldf.fill.nta f39 =[in0],loc0
+ ldf.fill.nta f47 =[ r3],loc0
+ ldf.fill.nta f55 =[r14],loc0
+ ldf.fill.nta f63 =[r15],loc0
+ ;;
+ ldf.fill.nta f71 =[in0],loc0
+ ldf.fill.nta f79 =[ r3],loc0
+ ldf.fill.nta f87 =[r14],loc0
+ ldf.fill.nta f95 =[r15],loc0
+ ;;
+ ldf.fill.nta f103=[in0]
+ ldf.fill.nta f111=[ r3]
+ ldf.fill.nta f119=[r14]
+ ldf.fill.nta f127=[r15]
+ br.ret.sptk.many rp
+END(__ia64_load_fpu)
+
+GLOBAL_ENTRY(__ia64_init_fpu)
+ stf.spill [sp]=f0 // M3
+ mov f32=f0 // F
+ nop.b 0
+
+ ldfps f33,f34=[sp] // M0
+ ldfps f35,f36=[sp] // M1
+ mov f37=f0 // F
+ ;;
+
+ setf.s f38=r0 // M2
+ setf.s f39=r0 // M3
+ mov f40=f0 // F
+
+ ldfps f41,f42=[sp] // M0
+ ldfps f43,f44=[sp] // M1
+ mov f45=f0 // F
+
+ setf.s f46=r0 // M2
+ setf.s f47=r0 // M3
+ mov f48=f0 // F
+
+ ldfps f49,f50=[sp] // M0
+ ldfps f51,f52=[sp] // M1
+ mov f53=f0 // F
+
+ setf.s f54=r0 // M2
+ setf.s f55=r0 // M3
+ mov f56=f0 // F
+
+ ldfps f57,f58=[sp] // M0
+ ldfps f59,f60=[sp] // M1
+ mov f61=f0 // F
+
+ setf.s f62=r0 // M2
+ setf.s f63=r0 // M3
+ mov f64=f0 // F
+
+ ldfps f65,f66=[sp] // M0
+ ldfps f67,f68=[sp] // M1
+ mov f69=f0 // F
+
+ setf.s f70=r0 // M2
+ setf.s f71=r0 // M3
+ mov f72=f0 // F
+
+ ldfps f73,f74=[sp] // M0
+ ldfps f75,f76=[sp] // M1
+ mov f77=f0 // F
+
+ setf.s f78=r0 // M2
+ setf.s f79=r0 // M3
+ mov f80=f0 // F
+
+ ldfps f81,f82=[sp] // M0
+ ldfps f83,f84=[sp] // M1
+ mov f85=f0 // F
+
+ setf.s f86=r0 // M2
+ setf.s f87=r0 // M3
+ mov f88=f0 // F
+
+ /*
+ * When the instructions are cached, it would be faster to initialize
+ * the remaining registers with simply mov instructions (F-unit).
+ * This gets the time down to ~29 cycles. However, this would use up
+ * 33 bundles, whereas continuing with the above pattern yields
+ * 10 bundles and ~30 cycles.
+ */
+
+ ldfps f89,f90=[sp] // M0
+ ldfps f91,f92=[sp] // M1
+ mov f93=f0 // F
+
+ setf.s f94=r0 // M2
+ setf.s f95=r0 // M3
+ mov f96=f0 // F
+
+ ldfps f97,f98=[sp] // M0
+ ldfps f99,f100=[sp] // M1
+ mov f101=f0 // F
+
+ setf.s f102=r0 // M2
+ setf.s f103=r0 // M3
+ mov f104=f0 // F
+
+ ldfps f105,f106=[sp] // M0
+ ldfps f107,f108=[sp] // M1
+ mov f109=f0 // F
+
+ setf.s f110=r0 // M2
+ setf.s f111=r0 // M3
+ mov f112=f0 // F
+
+ ldfps f113,f114=[sp] // M0
+ ldfps f115,f116=[sp] // M1
+ mov f117=f0 // F
+
+ setf.s f118=r0 // M2
+ setf.s f119=r0 // M3
+ mov f120=f0 // F
+
+ ldfps f121,f122=[sp] // M0
+ ldfps f123,f124=[sp] // M1
+ mov f125=f0 // F
+
+ setf.s f126=r0 // M2
+ setf.s f127=r0 // M3
+ br.ret.sptk.many rp // F
+END(__ia64_init_fpu)
+
+/*
+ * Switch execution mode from virtual to physical
+ *
+ * Inputs:
+ * r16 = new psr to establish
+ * Output:
+ * r19 = old virtual address of ar.bsp
+ * r20 = old virtual address of sp
+ *
+ * Note: RSE must already be in enforced lazy mode
+ */
+GLOBAL_ENTRY(ia64_switch_mode_phys)
+ {
+ alloc r2=ar.pfs,0,0,0,0
+ rsm psr.i | psr.ic // disable interrupts and interrupt collection
+ mov r15=ip
+ }
+ ;;
+ {
+ flushrs // must be first insn in group
+ srlz.i
+ }
+ ;;
+ mov cr.ipsr=r16 // set new PSR
+ add r3=1f-ia64_switch_mode_phys,r15
+
+ mov r19=ar.bsp
+ mov r20=sp
+ mov r14=rp // get return address into a general register
+ ;;
+
+ // going to physical mode, use tpa to translate virt->phys
+ tpa r17=r19
+ tpa r3=r3
+ tpa sp=sp
+ tpa r14=r14
+ ;;
+
+ mov r18=ar.rnat // save ar.rnat
+ mov ar.bspstore=r17 // this steps on ar.rnat
+ mov cr.iip=r3
+ mov cr.ifs=r0
+ ;;
+ mov ar.rnat=r18 // restore ar.rnat
+ rfi // must be last insn in group
+ ;;
+1: mov rp=r14
+ br.ret.sptk.many rp
+END(ia64_switch_mode_phys)
+
+/*
+ * Switch execution mode from physical to virtual
+ *
+ * Inputs:
+ * r16 = new psr to establish
+ * r19 = new bspstore to establish
+ * r20 = new sp to establish
+ *
+ * Note: RSE must already be in enforced lazy mode
+ */
+GLOBAL_ENTRY(ia64_switch_mode_virt)
+ {
+ alloc r2=ar.pfs,0,0,0,0
+ rsm psr.i | psr.ic // disable interrupts and interrupt collection
+ mov r15=ip
+ }
+ ;;
+ {
+ flushrs // must be first insn in group
+ srlz.i
+ }
+ ;;
+ mov cr.ipsr=r16 // set new PSR
+ add r3=1f-ia64_switch_mode_virt,r15
+
+ mov r14=rp // get return address into a general register
+ ;;
+
+ // going to virtual
+ // - for code addresses, set upper bits of addr to KERNEL_START
+ // - for stack addresses, copy from input argument
+ movl r18=KERNEL_START
+ dep r3=0,r3,KERNEL_TR_PAGE_SHIFT,64-KERNEL_TR_PAGE_SHIFT
+ dep r14=0,r14,KERNEL_TR_PAGE_SHIFT,64-KERNEL_TR_PAGE_SHIFT
+ mov sp=r20
+ ;;
+ or r3=r3,r18
+ or r14=r14,r18
+ ;;
+
+ mov r18=ar.rnat // save ar.rnat
+ mov ar.bspstore=r19 // this steps on ar.rnat
+ mov cr.iip=r3
+ mov cr.ifs=r0
+ ;;
+ mov ar.rnat=r18 // restore ar.rnat
+ rfi // must be last insn in group
+ ;;
+1: mov rp=r14
+ br.ret.sptk.many rp
+END(ia64_switch_mode_virt)
+
+GLOBAL_ENTRY(ia64_delay_loop)
+ .prologue
+{ nop 0 // work around GAS unwind info generation bug...
+ .save ar.lc,r2
+ mov r2=ar.lc
+ .body
+ ;;
+ mov ar.lc=r32
+}
+ ;;
+ // force loop to be 32-byte aligned (GAS bug means we cannot use .align
+ // inside function body without corrupting unwind info).
+{ nop 0 }
+1: br.cloop.sptk.few 1b
+ ;;
+ mov ar.lc=r2
+ br.ret.sptk.many rp
+END(ia64_delay_loop)
+
+/*
+ * Return a CPU-local timestamp in nano-seconds. This timestamp is
+ * NOT synchronized across CPUs its return value must never be
+ * compared against the values returned on another CPU. The usage in
+ * kernel/sched.c ensures that.
+ *
+ * The return-value of sched_clock() is NOT supposed to wrap-around.
+ * If it did, it would cause some scheduling hiccups (at the worst).
+ * Fortunately, with a 64-bit cycle-counter ticking at 100GHz, even
+ * that would happen only once every 5+ years.
+ *
+ * The code below basically calculates:
+ *
+ * (ia64_get_itc() * local_cpu_data->nsec_per_cyc) >> IA64_NSEC_PER_CYC_SHIFT
+ *
+ * except that the multiplication and the shift are done with 128-bit
+ * intermediate precision so that we can produce a full 64-bit result.
+ */
+GLOBAL_ENTRY(sched_clock)
+ addl r8=THIS_CPU(cpu_info) + IA64_CPUINFO_NSEC_PER_CYC_OFFSET,r0
+ mov.m r9=ar.itc // fetch cycle-counter (35 cyc)
+ ;;
+ ldf8 f8=[r8]
+ ;;
+ setf.sig f9=r9 // certain to stall, so issue it _after_ ldf8...
+ ;;
+ xmpy.lu f10=f9,f8 // calculate low 64 bits of 128-bit product (4 cyc)
+ xmpy.hu f11=f9,f8 // calculate high 64 bits of 128-bit product
+ ;;
+ getf.sig r8=f10 // (5 cyc)
+ getf.sig r9=f11
+ ;;
+ shrp r8=r9,r8,IA64_NSEC_PER_CYC_SHIFT
+ br.ret.sptk.many rp
+END(sched_clock)
+
+GLOBAL_ENTRY(start_kernel_thread)
+ .prologue
+ .save rp, r0 // this is the end of the call-chain
+ .body
+ alloc r2 = ar.pfs, 0, 0, 2, 0
+ mov out0 = r9
+ mov out1 = r11;;
+ br.call.sptk.many rp = kernel_thread_helper;;
+ mov out0 = r8
+ br.call.sptk.many rp = sys_exit;;
+1: br.sptk.few 1b // not reached
+END(start_kernel_thread)
+
+#ifdef CONFIG_IA64_BRL_EMU
+
+/*
+ * Assembly routines used by brl_emu.c to set preserved register state.
+ */
+
+#define SET_REG(reg) \
+ GLOBAL_ENTRY(ia64_set_##reg); \
+ alloc r16=ar.pfs,1,0,0,0; \
+ mov reg=r32; \
+ ;; \
+ br.ret.sptk.many rp; \
+ END(ia64_set_##reg)
+
+SET_REG(b1);
+SET_REG(b2);
+SET_REG(b3);
+SET_REG(b4);
+SET_REG(b5);
+
+#endif /* CONFIG_IA64_BRL_EMU */
+
+#ifdef CONFIG_SMP
+ /*
+ * This routine handles spinlock contention. It uses a non-standard calling
+ * convention to avoid converting leaf routines into interior routines. Because
+ * of this special convention, there are several restrictions:
+ *
+ * - do not use gp relative variables, this code is called from the kernel
+ * and from modules, r1 is undefined.
+ * - do not use stacked registers, the caller owns them.
+ * - do not use the scratch stack space, the caller owns it.
+ * - do not use any registers other than the ones listed below
+ *
+ * Inputs:
+ * ar.pfs - saved CFM of caller
+ * ar.ccv - 0 (and available for use)
+ * r27 - flags from spin_lock_irqsave or 0. Must be preserved.
+ * r28 - available for use.
+ * r29 - available for use.
+ * r30 - available for use.
+ * r31 - address of lock, available for use.
+ * b6 - return address
+ * p14 - available for use.
+ * p15 - used to track flag status.
+ *
+ * If you patch this code to use more registers, do not forget to update
+ * the clobber lists for spin_lock() in include/asm-ia64/spinlock.h.
+ */
+
+#if __GNUC__ < 3 || (__GNUC__ == 3 && __GNUC_MINOR__ < 3)
+
+GLOBAL_ENTRY(ia64_spinlock_contention_pre3_4)
+ .prologue
+ .save ar.pfs, r0 // this code effectively has a zero frame size
+ .save rp, r28
+ .body
+ nop 0
+ tbit.nz p15,p0=r27,IA64_PSR_I_BIT
+ .restore sp // pop existing prologue after next insn
+ mov b6 = r28
+ .prologue
+ .save ar.pfs, r0
+ .altrp b6
+ .body
+ ;;
+(p15) ssm psr.i // reenable interrupts if they were on
+ // DavidM says that srlz.d is slow and is not required in this case
+.wait:
+ // exponential backoff, kdb, lockmeter etc. go in here
+ hint @pause
+ ld4 r30=[r31] // don't use ld4.bias; if it's contended, we won't write the word
+ nop 0
+ ;;
+ cmp4.ne p14,p0=r30,r0
+(p14) br.cond.sptk.few .wait
+(p15) rsm psr.i // disable interrupts if we reenabled them
+ br.cond.sptk.few b6 // lock is now free, try to acquire
+ .global ia64_spinlock_contention_pre3_4_end // for kernprof
+ia64_spinlock_contention_pre3_4_end:
+END(ia64_spinlock_contention_pre3_4)
+
+#else
+
+GLOBAL_ENTRY(ia64_spinlock_contention)
+ .prologue
+ .altrp b6
+ .body
+ tbit.nz p15,p0=r27,IA64_PSR_I_BIT
+ ;;
+.wait:
+(p15) ssm psr.i // reenable interrupts if they were on
+ // DavidM says that srlz.d is slow and is not required in this case
+.wait2:
+ // exponential backoff, kdb, lockmeter etc. go in here
+ hint @pause
+ ld4 r30=[r31] // don't use ld4.bias; if it's contended, we won't write the word
+ ;;
+ cmp4.ne p14,p0=r30,r0
+ mov r30 = 1
+(p14) br.cond.sptk.few .wait2
+(p15) rsm psr.i // disable interrupts if we reenabled them
+ ;;
+ cmpxchg4.acq r30=[r31], r30, ar.ccv
+ ;;
+ cmp4.ne p14,p0=r0,r30
+(p14) br.cond.sptk.few .wait
+
+ br.ret.sptk.many b6 // lock is now taken
+END(ia64_spinlock_contention)
+
+#endif
+
+#endif /* CONFIG_SMP */