Changes in kernel/arch/ppc32/src/exception.S [9d58539:3fde837] in mainline

File:

• kernel/arch/ppc32/src/exception.S (modified) (4 diffs)

kernel/arch/ppc32/src/exception.S

@@ -30 +30 @@
 #include <arch/msr.h>
 #include <arch/mm/page.h>
+#include <arch/istate_struct.h>
+#include <arch/stack.h>
+#include <align.h>
 
 .section K_UNMAPPED_TEXT_START, "ax"
@@ -42 +45 @@
         mtsprg2 sp
         
-        # check whether SP is in kernel
-        
-        andis. sp, sp, 0x8000
+        # check whether the previous mode was user or kernel
+        
+        mfsrr1 sp # use sp as a temporary register to hold SRR1
+        andi. sp, sp, MSR_PR 
         bne 1f
-        
-                # stack is in user-space
-                
-                mfsprg0 sp
-        
-        b 2f
-        
-        1:
-        
-                # stack is in kernel
+                # previous mode was kernel
                 
                 mfsprg2 sp
                 subis sp, sp, 0x8000
-        
+        b 2f
+        
+        1:
+                # previous mode was user
+                
+                mfsprg0 sp
         2:
         
-        subi sp, sp, 164
-        stw r0, 8(sp)
-        stw r2, 12(sp)
-        stw r3, 16(sp)
-        stw r4, 20(sp)
-        stw r5, 24(sp)
-        stw r6, 28(sp)
-        stw r7, 32(sp)
-        stw r8, 36(sp)
-        stw r9, 40(sp)
-        stw r10, 44(sp)
-        stw r11, 48(sp)
-        stw r13, 52(sp)
-        stw r14, 56(sp)
-        stw r15, 60(sp)
-        stw r16, 64(sp)
-        stw r17, 68(sp)
-        stw r18, 72(sp)
-        stw r19, 76(sp)
-        stw r20, 80(sp)
-        stw r21, 84(sp)
-        stw r22, 88(sp)
-        stw r23, 92(sp)
-        stw r24, 96(sp)
-        stw r25, 100(sp)
-        stw r26, 104(sp)
-        stw r27, 108(sp)
-        stw r28, 112(sp)
-        stw r29, 116(sp)
-        stw r30, 120(sp)
-        stw r31, 124(sp)
-        
-        stw r12, 128(sp)
+        subi sp, sp, ALIGN_UP(ISTATE_SIZE, STACK_ALIGNMENT)
+        stw r0, ISTATE_OFFSET_R0(sp)
+        stw r2, ISTATE_OFFSET_R2(sp)
+        stw r3, ISTATE_OFFSET_R3(sp)
+        stw r4, ISTATE_OFFSET_R4(sp)
+        stw r5, ISTATE_OFFSET_R5(sp)
+        stw r6, ISTATE_OFFSET_R6(sp)
+        stw r7, ISTATE_OFFSET_R7(sp)
+        stw r8, ISTATE_OFFSET_R8(sp)
+        stw r9, ISTATE_OFFSET_R9(sp)
+        stw r10, ISTATE_OFFSET_R10(sp)
+        stw r11, ISTATE_OFFSET_R11(sp)
+        stw r13, ISTATE_OFFSET_R13(sp)
+        stw r14, ISTATE_OFFSET_R14(sp)
+        stw r15, ISTATE_OFFSET_R15(sp)
+        stw r16, ISTATE_OFFSET_R16(sp)
+        stw r17, ISTATE_OFFSET_R17(sp)
+        stw r18, ISTATE_OFFSET_R18(sp)
+        stw r19, ISTATE_OFFSET_R19(sp)
+        stw r20, ISTATE_OFFSET_R20(sp)
+        stw r21, ISTATE_OFFSET_R21(sp)
+        stw r22, ISTATE_OFFSET_R22(sp)
+        stw r23, ISTATE_OFFSET_R23(sp)
+        stw r24, ISTATE_OFFSET_R24(sp)
+        stw r25, ISTATE_OFFSET_R25(sp)
+        stw r26, ISTATE_OFFSET_R26(sp)
+        stw r27, ISTATE_OFFSET_R27(sp)
+        stw r28, ISTATE_OFFSET_R28(sp)
+        stw r29, ISTATE_OFFSET_R29(sp)
+        stw r30, ISTATE_OFFSET_R30(sp)
+        stw r31, ISTATE_OFFSET_R31(sp)
+        
+        stw r12, ISTATE_OFFSET_CR(sp)
         
         mfsrr0 r12
-        stw r12, 132(sp)
+        stw r12, ISTATE_OFFSET_PC(sp)
         
         mfsrr1 r12
-        stw r12, 136(sp)
+        stw r12, ISTATE_OFFSET_SRR1(sp)
         
         mflr r12
-        stw r12, 140(sp)
+        stw r12, ISTATE_OFFSET_LR(sp)
         
         mfctr r12
-        stw r12, 144(sp)
+        stw r12, ISTATE_OFFSET_CTR(sp)
         
         mfxer r12
-        stw r12, 148(sp)
+        stw r12, ISTATE_OFFSET_XER(sp)
         
         mfdar r12
-        stw r12, 152(sp)
+        stw r12, ISTATE_OFFSET_DAR(sp)
         
         mfsprg1 r12
-        stw r12, 156(sp)
+        stw r12, ISTATE_OFFSET_R12(sp)
         
         mfsprg2 r12
-        stw r12, 160(sp)
+        stw r12, ISTATE_OFFSET_SP(sp)
+
+        li r12, 0
+        stw r12, ISTATE_OFFSET_LR_FRAME(sp)
+        stw r12, ISTATE_OFFSET_SP_FRAME(sp)
 .endm
 
@@ -250 +254 @@
 .org 0x4000
 jump_to_kernel:
+        mfsrr1 r5
+        andi. r5, r5, MSR_PR
+        bne 1f
+                # Previous mode was kernel.
+                # We can construct a proper frame linkage.
+                
+                mfsrr0 r12
+                stw r12, ISTATE_OFFSET_LR_FRAME(sp)
+                mfsprg2 r12
+                stw r12, ISTATE_OFFSET_SP_FRAME(sp)
+        1:
+
         lis r12, iret@ha
         addi r12, r12, iret@l
         mtlr r12
-        
+
         lis r12, exc_dispatch@ha
         addi r12, r12, exc_dispatch@l
         mtsrr0 r12
-        
+
         mfmsr r12
-        ori r12, r12, (MSR_IR | MSR_DR)@l
+        mfsrr1 r5
+        andi. r5, r5, MSR_FP
+        or r12, r12, r5         # Propagate MSR_FP from SRR1 to MSR
+        ori r12, r12, (MSR_IR | MSR_DR)
         mtsrr1 r12
         
         addis sp, sp, 0x8000
         mr r4, sp
-        addi r4, r4, 8
         
         rfi
@@ -276 +294 @@
         addi r12, r12, iret_syscall@l
         mtlr r12
-        
+
+        mfsrr1 r0
+        andi. r0, r0, MSR_FP
         mfmsr r12
-        ori r12, r12, (MSR_IR | MSR_DR)@l
+        or r12, r12, r0         # Propagate MSR_FP from SRR1 to MSR
+        ori r12, r12, (MSR_IR | MSR_DR)
         mtsrr1 r12