ia64/xen-unstable

view xen/arch/ia64/linux/efi_stub.S @ 10888:5379548bfc79

[NET] Enable TCPv4 segmentation offload in front/back drivers.
Signed-off-by: Keir Fraser <keir@xensource.com>
author kfraser@localhost.localdomain
date Tue Aug 01 11:54:45 2006 +0100 (2006-08-01)
parents 9312a3e8a6f8
children
line source
1 /*
2 * EFI call stub.
3 *
4 * Copyright (C) 1999-2001 Hewlett-Packard Co
5 * David Mosberger <davidm@hpl.hp.com>
6 *
7 * This stub allows us to make EFI calls in physical mode with interrupts
8 * turned off. We need this because we can't call SetVirtualMap() until
9 * the kernel has booted far enough to allow allocation of struct vma_struct
10 * entries (which we would need to map stuff with memory attributes other
11 * than uncached or writeback...). Since the GetTime() service gets called
12 * earlier than that, we need to be able to make physical mode EFI calls from
13 * the kernel.
14 */
16 /*
17 * PSR settings as per SAL spec (Chapter 8 in the "IA-64 System
18 * Abstraction Layer Specification", revision 2.6e). Note that
19 * psr.dfl and psr.dfh MUST be cleared, despite what this manual says.
20 * Otherwise, SAL dies whenever it's trying to do an IA-32 BIOS call
21 * (the br.ia instruction fails unless psr.dfl and psr.dfh are
22 * cleared). Fortunately, SAL promises not to touch the floating
23 * point regs, so at least we don't have to save f2-f127.
24 */
25 #define PSR_BITS_TO_CLEAR \
26 (IA64_PSR_I | IA64_PSR_IT | IA64_PSR_DT | IA64_PSR_RT | \
27 IA64_PSR_DD | IA64_PSR_SS | IA64_PSR_RI | IA64_PSR_ED | \
28 IA64_PSR_DFL | IA64_PSR_DFH)
30 #define PSR_BITS_TO_SET \
31 (IA64_PSR_BN)
33 #include <asm/processor.h>
34 #include <asm/asmmacro.h>
36 /*
37 * Inputs:
38 * in0 = address of function descriptor of EFI routine to call
39 * in1..in7 = arguments to routine
40 *
41 * Outputs:
42 * r8 = EFI_STATUS returned by called function
43 */
45 GLOBAL_ENTRY(efi_call_phys)
46 .prologue ASM_UNW_PRLG_RP|ASM_UNW_PRLG_PFS, ASM_UNW_PRLG_GRSAVE(8)
47 alloc loc1=ar.pfs,8,7,7,0
48 ld8 r2=[in0],8 // load EFI function's entry point
49 mov loc0=rp
50 .body
51 ;;
52 mov loc2=gp // save global pointer
53 mov loc4=ar.rsc // save RSE configuration
54 mov ar.rsc=0 // put RSE in enforced lazy, LE mode
55 ;;
56 ld8 gp=[in0] // load EFI function's global pointer
57 movl r16=PSR_BITS_TO_CLEAR
58 mov loc3=psr // save processor status word
59 movl r17=PSR_BITS_TO_SET
60 ;;
61 or loc3=loc3,r17
62 mov b6=r2
63 ;;
64 andcm r16=loc3,r16 // get psr with IT, DT, and RT bits cleared
65 br.call.sptk.many rp=ia64_switch_mode_phys
66 .ret0: mov out4=in5
67 mov out0=in1
68 mov out1=in2
69 mov out2=in3
70 mov out3=in4
71 mov out5=in6
72 mov out6=in7
73 mov loc5=r19
74 mov loc6=r20
75 br.call.sptk.many rp=b6 // call the EFI function
76 .ret1: mov ar.rsc=0 // put RSE in enforced lazy, LE mode
77 mov r16=loc3
78 mov r19=loc5
79 mov r20=loc6
80 br.call.sptk.many rp=ia64_switch_mode_virt // return to virtual mode
81 .ret2: mov ar.rsc=loc4 // restore RSE configuration
82 mov ar.pfs=loc1
83 mov rp=loc0
84 mov gp=loc2
85 br.ret.sptk.many rp
86 END(efi_call_phys)