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-rw-r--r--arch/arm/vfp/entry.S1
-rw-r--r--arch/arm/vfp/vfp.h4
-rw-r--r--arch/arm/vfp/vfphw.S26
-rw-r--r--arch/arm/vfp/vfpmodule.c30
4 files changed, 55 insertions, 6 deletions
diff --git a/arch/arm/vfp/entry.S b/arch/arm/vfp/entry.S
index 7b595547c1c8..ca2a5ad19ea6 100644
--- a/arch/arm/vfp/entry.S
+++ b/arch/arm/vfp/entry.S
@@ -25,6 +25,7 @@
25do_vfp: 25do_vfp:
26 enable_irq 26 enable_irq
27 ldr r4, .LCvfp 27 ldr r4, .LCvfp
28 ldr r11, [r10, #TI_CPU] @ CPU number
28 add r10, r10, #TI_VFPSTATE @ r10 = workspace 29 add r10, r10, #TI_VFPSTATE @ r10 = workspace
29 ldr pc, [r4] @ call VFP entry point 30 ldr pc, [r4] @ call VFP entry point
30 31
diff --git a/arch/arm/vfp/vfp.h b/arch/arm/vfp/vfp.h
index f2797896e6d5..54a2ad6d9ca2 100644
--- a/arch/arm/vfp/vfp.h
+++ b/arch/arm/vfp/vfp.h
@@ -370,3 +370,7 @@ struct op {
370 u32 (* const fn)(int dd, int dn, int dm, u32 fpscr); 370 u32 (* const fn)(int dd, int dn, int dm, u32 fpscr);
371 u32 flags; 371 u32 flags;
372}; 372};
373
374#ifdef CONFIG_SMP
375extern void vfp_save_state(void *location, u32 fpexc);
376#endif
diff --git a/arch/arm/vfp/vfphw.S b/arch/arm/vfp/vfphw.S
index e51e6679c402..d4b7b229631d 100644
--- a/arch/arm/vfp/vfphw.S
+++ b/arch/arm/vfp/vfphw.S
@@ -65,6 +65,7 @@
65@ r2 = faulted PC+4 65@ r2 = faulted PC+4
66@ r9 = successful return 66@ r9 = successful return
67@ r10 = vfp_state union 67@ r10 = vfp_state union
68@ r11 = CPU number
68@ lr = failure return 69@ lr = failure return
69 70
70 .globl vfp_support_entry 71 .globl vfp_support_entry
@@ -79,7 +80,7 @@ vfp_support_entry:
79 DBGSTR1 "enable %x", r10 80 DBGSTR1 "enable %x", r10
80 ldr r3, last_VFP_context_address 81 ldr r3, last_VFP_context_address
81 orr r1, r1, #FPEXC_ENABLE @ user FPEXC has the enable bit set 82 orr r1, r1, #FPEXC_ENABLE @ user FPEXC has the enable bit set
82 ldr r4, [r3] @ last_VFP_context pointer 83 ldr r4, [r3, r11, lsl #2] @ last_VFP_context pointer
83 bic r5, r1, #FPEXC_EXCEPTION @ make sure exceptions are disabled 84 bic r5, r1, #FPEXC_EXCEPTION @ make sure exceptions are disabled
84 cmp r4, r10 85 cmp r4, r10
85 beq check_for_exception @ we are returning to the same 86 beq check_for_exception @ we are returning to the same
@@ -91,7 +92,9 @@ vfp_support_entry:
91 @ exceptions, so we can get at the 92 @ exceptions, so we can get at the
92 @ rest of it 93 @ rest of it
93 94
95#ifndef CONFIG_SMP
94 @ Save out the current registers to the old thread state 96 @ Save out the current registers to the old thread state
97 @ No need for SMP since this is not done lazily
95 98
96 DBGSTR1 "save old state %p", r4 99 DBGSTR1 "save old state %p", r4
97 cmp r4, #0 100 cmp r4, #0
@@ -105,10 +108,11 @@ vfp_support_entry:
105 stmia r4, {r1, r5, r6, r8} @ save FPEXC, FPSCR, FPINST, FPINST2 108 stmia r4, {r1, r5, r6, r8} @ save FPEXC, FPSCR, FPINST, FPINST2
106 @ and point r4 at the word at the 109 @ and point r4 at the word at the
107 @ start of the register dump 110 @ start of the register dump
111#endif
108 112
109no_old_VFP_process: 113no_old_VFP_process:
110 DBGSTR1 "load state %p", r10 114 DBGSTR1 "load state %p", r10
111 str r10, [r3] @ update the last_VFP_context pointer 115 str r10, [r3, r11, lsl #2] @ update the last_VFP_context pointer
112 @ Load the saved state back into the VFP 116 @ Load the saved state back into the VFP
113 VFPFLDMIA r10 @ reload the working registers while 117 VFPFLDMIA r10 @ reload the working registers while
114 @ FPEXC is in a safe state 118 @ FPEXC is in a safe state
@@ -162,6 +166,24 @@ process_exception:
162 @ required. If not, the user code will 166 @ required. If not, the user code will
163 @ retry the faulted instruction 167 @ retry the faulted instruction
164 168
169#ifdef CONFIG_SMP
170 .globl vfp_save_state
171 .type vfp_save_state, %function
172vfp_save_state:
173 @ Save the current VFP state
174 @ r0 - save location
175 @ r1 - FPEXC
176 DBGSTR1 "save VFP state %p", r0
177 VFPFMRX r2, FPSCR @ current status
178 VFPFMRX r3, FPINST @ FPINST (always there, rev0 onwards)
179 tst r1, #FPEXC_FPV2 @ is there an FPINST2 to read?
180 VFPFMRX r12, FPINST2, NE @ FPINST2 if needed - avoids reading
181 @ nonexistant reg on rev0
182 VFPFSTMIA r0 @ save the working registers
183 stmia r0, {r1, r2, r3, r12} @ save FPEXC, FPSCR, FPINST, FPINST2
184 mov pc, lr
185#endif
186
165last_VFP_context_address: 187last_VFP_context_address:
166 .word last_VFP_context 188 .word last_VFP_context
167 189
diff --git a/arch/arm/vfp/vfpmodule.c b/arch/arm/vfp/vfpmodule.c
index 490d9d18a7d1..f1e5951dc721 100644
--- a/arch/arm/vfp/vfpmodule.c
+++ b/arch/arm/vfp/vfpmodule.c
@@ -28,7 +28,7 @@ void vfp_testing_entry(void);
28void vfp_support_entry(void); 28void vfp_support_entry(void);
29 29
30void (*vfp_vector)(void) = vfp_testing_entry; 30void (*vfp_vector)(void) = vfp_testing_entry;
31union vfp_state *last_VFP_context; 31union vfp_state *last_VFP_context[NR_CPUS];
32 32
33/* 33/*
34 * Dual-use variable. 34 * Dual-use variable.
@@ -41,13 +41,35 @@ static int vfp_notifier(struct notifier_block *self, unsigned long cmd, void *v)
41{ 41{
42 struct thread_info *thread = v; 42 struct thread_info *thread = v;
43 union vfp_state *vfp; 43 union vfp_state *vfp;
44 __u32 cpu = thread->cpu;
44 45
45 if (likely(cmd == THREAD_NOTIFY_SWITCH)) { 46 if (likely(cmd == THREAD_NOTIFY_SWITCH)) {
47 u32 fpexc = fmrx(FPEXC);
48
49#ifdef CONFIG_SMP
50 /*
51 * On SMP, if VFP is enabled, save the old state in
52 * case the thread migrates to a different CPU. The
53 * restoring is done lazily.
54 */
55 if ((fpexc & FPEXC_ENABLE) && last_VFP_context[cpu]) {
56 vfp_save_state(last_VFP_context[cpu], fpexc);
57 last_VFP_context[cpu]->hard.cpu = cpu;
58 }
59 /*
60 * Thread migration, just force the reloading of the
61 * state on the new CPU in case the VFP registers
62 * contain stale data.
63 */
64 if (thread->vfpstate.hard.cpu != cpu)
65 last_VFP_context[cpu] = NULL;
66#endif
67
46 /* 68 /*
47 * Always disable VFP so we can lazily save/restore the 69 * Always disable VFP so we can lazily save/restore the
48 * old state. 70 * old state.
49 */ 71 */
50 fmxr(FPEXC, fmrx(FPEXC) & ~FPEXC_ENABLE); 72 fmxr(FPEXC, fpexc & ~FPEXC_ENABLE);
51 return NOTIFY_DONE; 73 return NOTIFY_DONE;
52 } 74 }
53 75
@@ -68,8 +90,8 @@ static int vfp_notifier(struct notifier_block *self, unsigned long cmd, void *v)
68 } 90 }
69 91
70 /* flush and release case: Per-thread VFP cleanup. */ 92 /* flush and release case: Per-thread VFP cleanup. */
71 if (last_VFP_context == vfp) 93 if (last_VFP_context[cpu] == vfp)
72 last_VFP_context = NULL; 94 last_VFP_context[cpu] = NULL;
73 95
74 return NOTIFY_DONE; 96 return NOTIFY_DONE;
75} 97}