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-rw-r--r--arch/powerpc/kernel/head_booke.h458
1 files changed, 458 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/head_booke.h b/arch/powerpc/kernel/head_booke.h
new file mode 100644
index 000000000..306e26c07
--- /dev/null
+++ b/arch/powerpc/kernel/head_booke.h
@@ -0,0 +1,458 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __HEAD_BOOKE_H__
+#define __HEAD_BOOKE_H__
+
+#include <asm/ptrace.h> /* for STACK_FRAME_REGS_MARKER */
+#include <asm/kvm_asm.h>
+#include <asm/kvm_booke_hv_asm.h>
+
+/*
+ * Macros used for common Book-e exception handling
+ */
+
+#define SET_IVOR(vector_number, vector_label) \
+ li r26,vector_label@l; \
+ mtspr SPRN_IVOR##vector_number,r26; \
+ sync
+
+#if (THREAD_SHIFT < 15)
+#define ALLOC_STACK_FRAME(reg, val) \
+ addi reg,reg,val
+#else
+#define ALLOC_STACK_FRAME(reg, val) \
+ addis reg,reg,val@ha; \
+ addi reg,reg,val@l
+#endif
+
+/*
+ * Macro used to get to thread save registers.
+ * Note that entries 0-3 are used for the prolog code, and the remaining
+ * entries are available for specific exception use in the event a handler
+ * requires more than 4 scratch registers.
+ */
+#define THREAD_NORMSAVE(offset) (THREAD_NORMSAVES + (offset * 4))
+
+#ifdef CONFIG_PPC_FSL_BOOK3E
+#define BOOKE_CLEAR_BTB(reg) \
+START_BTB_FLUSH_SECTION \
+ BTB_FLUSH(reg) \
+END_BTB_FLUSH_SECTION
+#else
+#define BOOKE_CLEAR_BTB(reg)
+#endif
+
+
+#define NORMAL_EXCEPTION_PROLOG(intno) \
+ mtspr SPRN_SPRG_WSCRATCH0, r10; /* save one register */ \
+ mfspr r10, SPRN_SPRG_THREAD; \
+ stw r11, THREAD_NORMSAVE(0)(r10); \
+ stw r13, THREAD_NORMSAVE(2)(r10); \
+ mfcr r13; /* save CR in r13 for now */\
+ mfspr r11, SPRN_SRR1; \
+ DO_KVM BOOKE_INTERRUPT_##intno SPRN_SRR1; \
+ andi. r11, r11, MSR_PR; /* check whether user or kernel */\
+ mr r11, r1; \
+ beq 1f; \
+ BOOKE_CLEAR_BTB(r11) \
+ /* if from user, start at top of this thread's kernel stack */ \
+ lwz r11, THREAD_INFO-THREAD(r10); \
+ ALLOC_STACK_FRAME(r11, THREAD_SIZE); \
+1 : subi r11, r11, INT_FRAME_SIZE; /* Allocate exception frame */ \
+ stw r13, _CCR(r11); /* save various registers */ \
+ stw r12,GPR12(r11); \
+ stw r9,GPR9(r11); \
+ mfspr r13, SPRN_SPRG_RSCRATCH0; \
+ stw r13, GPR10(r11); \
+ lwz r12, THREAD_NORMSAVE(0)(r10); \
+ stw r12,GPR11(r11); \
+ lwz r13, THREAD_NORMSAVE(2)(r10); /* restore r13 */ \
+ mflr r10; \
+ stw r10,_LINK(r11); \
+ mfspr r12,SPRN_SRR0; \
+ stw r1, GPR1(r11); \
+ mfspr r9,SPRN_SRR1; \
+ stw r1, 0(r11); \
+ mr r1, r11; \
+ rlwinm r9,r9,0,14,12; /* clear MSR_WE (necessary?) */\
+ stw r0,GPR0(r11); \
+ lis r10, STACK_FRAME_REGS_MARKER@ha;/* exception frame marker */ \
+ addi r10, r10, STACK_FRAME_REGS_MARKER@l; \
+ stw r10, 8(r11); \
+ SAVE_4GPRS(3, r11); \
+ SAVE_2GPRS(7, r11)
+
+/* To handle the additional exception priority levels on 40x and Book-E
+ * processors we allocate a stack per additional priority level.
+ *
+ * On 40x critical is the only additional level
+ * On 44x/e500 we have critical and machine check
+ * On e200 we have critical and debug (machine check occurs via critical)
+ *
+ * Additionally we reserve a SPRG for each priority level so we can free up a
+ * GPR to use as the base for indirect access to the exception stacks. This
+ * is necessary since the MMU is always on, for Book-E parts, and the stacks
+ * are offset from KERNELBASE.
+ *
+ * There is some space optimization to be had here if desired. However
+ * to allow for a common kernel with support for debug exceptions either
+ * going to critical or their own debug level we aren't currently
+ * providing configurations that micro-optimize space usage.
+ */
+
+#define MC_STACK_BASE mcheckirq_ctx
+#define CRIT_STACK_BASE critirq_ctx
+
+/* only on e500mc/e200 */
+#define DBG_STACK_BASE dbgirq_ctx
+
+#define EXC_LVL_FRAME_OVERHEAD (THREAD_SIZE - INT_FRAME_SIZE - EXC_LVL_SIZE)
+
+#ifdef CONFIG_SMP
+#define BOOKE_LOAD_EXC_LEVEL_STACK(level) \
+ mfspr r8,SPRN_PIR; \
+ slwi r8,r8,2; \
+ addis r8,r8,level##_STACK_BASE@ha; \
+ lwz r8,level##_STACK_BASE@l(r8); \
+ addi r8,r8,EXC_LVL_FRAME_OVERHEAD;
+#else
+#define BOOKE_LOAD_EXC_LEVEL_STACK(level) \
+ lis r8,level##_STACK_BASE@ha; \
+ lwz r8,level##_STACK_BASE@l(r8); \
+ addi r8,r8,EXC_LVL_FRAME_OVERHEAD;
+#endif
+
+/*
+ * Exception prolog for critical/machine check exceptions. This is a
+ * little different from the normal exception prolog above since a
+ * critical/machine check exception can potentially occur at any point
+ * during normal exception processing. Thus we cannot use the same SPRG
+ * registers as the normal prolog above. Instead we use a portion of the
+ * critical/machine check exception stack at low physical addresses.
+ */
+#define EXC_LEVEL_EXCEPTION_PROLOG(exc_level, intno, exc_level_srr0, exc_level_srr1) \
+ mtspr SPRN_SPRG_WSCRATCH_##exc_level,r8; \
+ BOOKE_LOAD_EXC_LEVEL_STACK(exc_level);/* r8 points to the exc_level stack*/ \
+ stw r9,GPR9(r8); /* save various registers */\
+ mfcr r9; /* save CR in r9 for now */\
+ stw r10,GPR10(r8); \
+ stw r11,GPR11(r8); \
+ stw r9,_CCR(r8); /* save CR on stack */\
+ mfspr r11,exc_level_srr1; /* check whether user or kernel */\
+ DO_KVM BOOKE_INTERRUPT_##intno exc_level_srr1; \
+ BOOKE_CLEAR_BTB(r10) \
+ andi. r11,r11,MSR_PR; \
+ mfspr r11,SPRN_SPRG_THREAD; /* if from user, start at top of */\
+ lwz r11,THREAD_INFO-THREAD(r11); /* this thread's kernel stack */\
+ addi r11,r11,EXC_LVL_FRAME_OVERHEAD; /* allocate stack frame */\
+ beq 1f; \
+ /* COMING FROM USER MODE */ \
+ stw r9,_CCR(r11); /* save CR */\
+ lwz r10,GPR10(r8); /* copy regs from exception stack */\
+ lwz r9,GPR9(r8); \
+ stw r10,GPR10(r11); \
+ lwz r10,GPR11(r8); \
+ stw r9,GPR9(r11); \
+ stw r10,GPR11(r11); \
+ b 2f; \
+ /* COMING FROM PRIV MODE */ \
+1: lwz r9,TI_FLAGS-EXC_LVL_FRAME_OVERHEAD(r11); \
+ lwz r10,TI_PREEMPT-EXC_LVL_FRAME_OVERHEAD(r11); \
+ stw r9,TI_FLAGS-EXC_LVL_FRAME_OVERHEAD(r8); \
+ stw r10,TI_PREEMPT-EXC_LVL_FRAME_OVERHEAD(r8); \
+ lwz r9,TI_TASK-EXC_LVL_FRAME_OVERHEAD(r11); \
+ stw r9,TI_TASK-EXC_LVL_FRAME_OVERHEAD(r8); \
+ mr r11,r8; \
+2: mfspr r8,SPRN_SPRG_RSCRATCH_##exc_level; \
+ stw r12,GPR12(r11); /* save various registers */\
+ mflr r10; \
+ stw r10,_LINK(r11); \
+ mfspr r12,SPRN_DEAR; /* save DEAR and ESR in the frame */\
+ stw r12,_DEAR(r11); /* since they may have had stuff */\
+ mfspr r9,SPRN_ESR; /* in them at the point where the */\
+ stw r9,_ESR(r11); /* exception was taken */\
+ mfspr r12,exc_level_srr0; \
+ stw r1,GPR1(r11); \
+ mfspr r9,exc_level_srr1; \
+ stw r1,0(r11); \
+ mr r1,r11; \
+ rlwinm r9,r9,0,14,12; /* clear MSR_WE (necessary?) */\
+ stw r0,GPR0(r11); \
+ SAVE_4GPRS(3, r11); \
+ SAVE_2GPRS(7, r11)
+
+#define CRITICAL_EXCEPTION_PROLOG(intno) \
+ EXC_LEVEL_EXCEPTION_PROLOG(CRIT, intno, SPRN_CSRR0, SPRN_CSRR1)
+#define DEBUG_EXCEPTION_PROLOG \
+ EXC_LEVEL_EXCEPTION_PROLOG(DBG, DEBUG, SPRN_DSRR0, SPRN_DSRR1)
+#define MCHECK_EXCEPTION_PROLOG \
+ EXC_LEVEL_EXCEPTION_PROLOG(MC, MACHINE_CHECK, \
+ SPRN_MCSRR0, SPRN_MCSRR1)
+
+/*
+ * Guest Doorbell -- this is a bit odd in that uses GSRR0/1 despite
+ * being delivered to the host. This exception can only happen
+ * inside a KVM guest -- so we just handle up to the DO_KVM rather
+ * than try to fit this into one of the existing prolog macros.
+ */
+#define GUEST_DOORBELL_EXCEPTION \
+ START_EXCEPTION(GuestDoorbell); \
+ mtspr SPRN_SPRG_WSCRATCH0, r10; /* save one register */ \
+ mfspr r10, SPRN_SPRG_THREAD; \
+ stw r11, THREAD_NORMSAVE(0)(r10); \
+ mfspr r11, SPRN_SRR1; \
+ stw r13, THREAD_NORMSAVE(2)(r10); \
+ mfcr r13; /* save CR in r13 for now */\
+ DO_KVM BOOKE_INTERRUPT_GUEST_DBELL SPRN_GSRR1; \
+ trap
+
+/*
+ * Exception vectors.
+ */
+#define START_EXCEPTION(label) \
+ .align 5; \
+label:
+
+#define EXCEPTION(n, intno, label, hdlr, xfer) \
+ START_EXCEPTION(label); \
+ NORMAL_EXCEPTION_PROLOG(intno); \
+ addi r3,r1,STACK_FRAME_OVERHEAD; \
+ xfer(n, hdlr)
+
+#define CRITICAL_EXCEPTION(n, intno, label, hdlr) \
+ START_EXCEPTION(label); \
+ CRITICAL_EXCEPTION_PROLOG(intno); \
+ addi r3,r1,STACK_FRAME_OVERHEAD; \
+ EXC_XFER_TEMPLATE(hdlr, n+2, (MSR_KERNEL & ~(MSR_ME|MSR_DE|MSR_CE)), \
+ NOCOPY, crit_transfer_to_handler, \
+ ret_from_crit_exc)
+
+#define MCHECK_EXCEPTION(n, label, hdlr) \
+ START_EXCEPTION(label); \
+ MCHECK_EXCEPTION_PROLOG; \
+ mfspr r5,SPRN_ESR; \
+ stw r5,_ESR(r11); \
+ addi r3,r1,STACK_FRAME_OVERHEAD; \
+ EXC_XFER_TEMPLATE(hdlr, n+4, (MSR_KERNEL & ~(MSR_ME|MSR_DE|MSR_CE)), \
+ NOCOPY, mcheck_transfer_to_handler, \
+ ret_from_mcheck_exc)
+
+#define EXC_XFER_TEMPLATE(hdlr, trap, msr, copyee, tfer, ret) \
+ li r10,trap; \
+ stw r10,_TRAP(r11); \
+ lis r10,msr@h; \
+ ori r10,r10,msr@l; \
+ copyee(r10, r9); \
+ bl tfer; \
+ .long hdlr; \
+ .long ret
+
+#define COPY_EE(d, s) rlwimi d,s,0,16,16
+#define NOCOPY(d, s)
+
+#define EXC_XFER_STD(n, hdlr) \
+ EXC_XFER_TEMPLATE(hdlr, n, MSR_KERNEL, NOCOPY, transfer_to_handler_full, \
+ ret_from_except_full)
+
+#define EXC_XFER_LITE(n, hdlr) \
+ EXC_XFER_TEMPLATE(hdlr, n+1, MSR_KERNEL, NOCOPY, transfer_to_handler, \
+ ret_from_except)
+
+#define EXC_XFER_EE(n, hdlr) \
+ EXC_XFER_TEMPLATE(hdlr, n, MSR_KERNEL, COPY_EE, transfer_to_handler_full, \
+ ret_from_except_full)
+
+#define EXC_XFER_EE_LITE(n, hdlr) \
+ EXC_XFER_TEMPLATE(hdlr, n+1, MSR_KERNEL, COPY_EE, transfer_to_handler, \
+ ret_from_except)
+
+/* Check for a single step debug exception while in an exception
+ * handler before state has been saved. This is to catch the case
+ * where an instruction that we are trying to single step causes
+ * an exception (eg ITLB/DTLB miss) and thus the first instruction of
+ * the exception handler generates a single step debug exception.
+ *
+ * If we get a debug trap on the first instruction of an exception handler,
+ * we reset the MSR_DE in the _exception handler's_ MSR (the debug trap is
+ * a critical exception, so we are using SPRN_CSRR1 to manipulate the MSR).
+ * The exception handler was handling a non-critical interrupt, so it will
+ * save (and later restore) the MSR via SPRN_CSRR1, which will still have
+ * the MSR_DE bit set.
+ */
+#define DEBUG_DEBUG_EXCEPTION \
+ START_EXCEPTION(DebugDebug); \
+ DEBUG_EXCEPTION_PROLOG; \
+ \
+ /* \
+ * If there is a single step or branch-taken exception in an \
+ * exception entry sequence, it was probably meant to apply to \
+ * the code where the exception occurred (since exception entry \
+ * doesn't turn off DE automatically). We simulate the effect \
+ * of turning off DE on entry to an exception handler by turning \
+ * off DE in the DSRR1 value and clearing the debug status. \
+ */ \
+ mfspr r10,SPRN_DBSR; /* check single-step/branch taken */ \
+ andis. r10,r10,(DBSR_IC|DBSR_BT)@h; \
+ beq+ 2f; \
+ \
+ lis r10,interrupt_base@h; /* check if exception in vectors */ \
+ ori r10,r10,interrupt_base@l; \
+ cmplw r12,r10; \
+ blt+ 2f; /* addr below exception vectors */ \
+ \
+ lis r10,interrupt_end@h; \
+ ori r10,r10,interrupt_end@l; \
+ cmplw r12,r10; \
+ bgt+ 2f; /* addr above exception vectors */ \
+ \
+ /* here it looks like we got an inappropriate debug exception. */ \
+1: rlwinm r9,r9,0,~MSR_DE; /* clear DE in the CDRR1 value */ \
+ lis r10,(DBSR_IC|DBSR_BT)@h; /* clear the IC event */ \
+ mtspr SPRN_DBSR,r10; \
+ /* restore state and get out */ \
+ lwz r10,_CCR(r11); \
+ lwz r0,GPR0(r11); \
+ lwz r1,GPR1(r11); \
+ mtcrf 0x80,r10; \
+ mtspr SPRN_DSRR0,r12; \
+ mtspr SPRN_DSRR1,r9; \
+ lwz r9,GPR9(r11); \
+ lwz r12,GPR12(r11); \
+ mtspr SPRN_SPRG_WSCRATCH_DBG,r8; \
+ BOOKE_LOAD_EXC_LEVEL_STACK(DBG); /* r8 points to the debug stack */ \
+ lwz r10,GPR10(r8); \
+ lwz r11,GPR11(r8); \
+ mfspr r8,SPRN_SPRG_RSCRATCH_DBG; \
+ \
+ PPC_RFDI; \
+ b .; \
+ \
+ /* continue normal handling for a debug exception... */ \
+2: mfspr r4,SPRN_DBSR; \
+ addi r3,r1,STACK_FRAME_OVERHEAD; \
+ EXC_XFER_TEMPLATE(DebugException, 0x2008, (MSR_KERNEL & ~(MSR_ME|MSR_DE|MSR_CE)), NOCOPY, debug_transfer_to_handler, ret_from_debug_exc)
+
+#define DEBUG_CRIT_EXCEPTION \
+ START_EXCEPTION(DebugCrit); \
+ CRITICAL_EXCEPTION_PROLOG(DEBUG); \
+ \
+ /* \
+ * If there is a single step or branch-taken exception in an \
+ * exception entry sequence, it was probably meant to apply to \
+ * the code where the exception occurred (since exception entry \
+ * doesn't turn off DE automatically). We simulate the effect \
+ * of turning off DE on entry to an exception handler by turning \
+ * off DE in the CSRR1 value and clearing the debug status. \
+ */ \
+ mfspr r10,SPRN_DBSR; /* check single-step/branch taken */ \
+ andis. r10,r10,(DBSR_IC|DBSR_BT)@h; \
+ beq+ 2f; \
+ \
+ lis r10,interrupt_base@h; /* check if exception in vectors */ \
+ ori r10,r10,interrupt_base@l; \
+ cmplw r12,r10; \
+ blt+ 2f; /* addr below exception vectors */ \
+ \
+ lis r10,interrupt_end@h; \
+ ori r10,r10,interrupt_end@l; \
+ cmplw r12,r10; \
+ bgt+ 2f; /* addr above exception vectors */ \
+ \
+ /* here it looks like we got an inappropriate debug exception. */ \
+1: rlwinm r9,r9,0,~MSR_DE; /* clear DE in the CSRR1 value */ \
+ lis r10,(DBSR_IC|DBSR_BT)@h; /* clear the IC event */ \
+ mtspr SPRN_DBSR,r10; \
+ /* restore state and get out */ \
+ lwz r10,_CCR(r11); \
+ lwz r0,GPR0(r11); \
+ lwz r1,GPR1(r11); \
+ mtcrf 0x80,r10; \
+ mtspr SPRN_CSRR0,r12; \
+ mtspr SPRN_CSRR1,r9; \
+ lwz r9,GPR9(r11); \
+ lwz r12,GPR12(r11); \
+ mtspr SPRN_SPRG_WSCRATCH_CRIT,r8; \
+ BOOKE_LOAD_EXC_LEVEL_STACK(CRIT); /* r8 points to the debug stack */ \
+ lwz r10,GPR10(r8); \
+ lwz r11,GPR11(r8); \
+ mfspr r8,SPRN_SPRG_RSCRATCH_CRIT; \
+ \
+ rfci; \
+ b .; \
+ \
+ /* continue normal handling for a critical exception... */ \
+2: mfspr r4,SPRN_DBSR; \
+ addi r3,r1,STACK_FRAME_OVERHEAD; \
+ EXC_XFER_TEMPLATE(DebugException, 0x2002, (MSR_KERNEL & ~(MSR_ME|MSR_DE|MSR_CE)), NOCOPY, crit_transfer_to_handler, ret_from_crit_exc)
+
+#define DATA_STORAGE_EXCEPTION \
+ START_EXCEPTION(DataStorage) \
+ NORMAL_EXCEPTION_PROLOG(DATA_STORAGE); \
+ mfspr r5,SPRN_ESR; /* Grab the ESR and save it */ \
+ stw r5,_ESR(r11); \
+ mfspr r4,SPRN_DEAR; /* Grab the DEAR */ \
+ EXC_XFER_LITE(0x0300, handle_page_fault)
+
+#define INSTRUCTION_STORAGE_EXCEPTION \
+ START_EXCEPTION(InstructionStorage) \
+ NORMAL_EXCEPTION_PROLOG(INST_STORAGE); \
+ mfspr r5,SPRN_ESR; /* Grab the ESR and save it */ \
+ stw r5,_ESR(r11); \
+ mr r4,r12; /* Pass SRR0 as arg2 */ \
+ li r5,0; /* Pass zero as arg3 */ \
+ EXC_XFER_LITE(0x0400, handle_page_fault)
+
+#define ALIGNMENT_EXCEPTION \
+ START_EXCEPTION(Alignment) \
+ NORMAL_EXCEPTION_PROLOG(ALIGNMENT); \
+ mfspr r4,SPRN_DEAR; /* Grab the DEAR and save it */ \
+ stw r4,_DEAR(r11); \
+ addi r3,r1,STACK_FRAME_OVERHEAD; \
+ EXC_XFER_EE(0x0600, alignment_exception)
+
+#define PROGRAM_EXCEPTION \
+ START_EXCEPTION(Program) \
+ NORMAL_EXCEPTION_PROLOG(PROGRAM); \
+ mfspr r4,SPRN_ESR; /* Grab the ESR and save it */ \
+ stw r4,_ESR(r11); \
+ addi r3,r1,STACK_FRAME_OVERHEAD; \
+ EXC_XFER_STD(0x0700, program_check_exception)
+
+#define DECREMENTER_EXCEPTION \
+ START_EXCEPTION(Decrementer) \
+ NORMAL_EXCEPTION_PROLOG(DECREMENTER); \
+ lis r0,TSR_DIS@h; /* Setup the DEC interrupt mask */ \
+ mtspr SPRN_TSR,r0; /* Clear the DEC interrupt */ \
+ addi r3,r1,STACK_FRAME_OVERHEAD; \
+ EXC_XFER_LITE(0x0900, timer_interrupt)
+
+#define FP_UNAVAILABLE_EXCEPTION \
+ START_EXCEPTION(FloatingPointUnavailable) \
+ NORMAL_EXCEPTION_PROLOG(FP_UNAVAIL); \
+ beq 1f; \
+ bl load_up_fpu; /* if from user, just load it up */ \
+ b fast_exception_return; \
+1: addi r3,r1,STACK_FRAME_OVERHEAD; \
+ EXC_XFER_EE_LITE(0x800, kernel_fp_unavailable_exception)
+
+#ifndef __ASSEMBLY__
+struct exception_regs {
+ unsigned long mas0;
+ unsigned long mas1;
+ unsigned long mas2;
+ unsigned long mas3;
+ unsigned long mas6;
+ unsigned long mas7;
+ unsigned long srr0;
+ unsigned long srr1;
+ unsigned long csrr0;
+ unsigned long csrr1;
+ unsigned long dsrr0;
+ unsigned long dsrr1;
+ unsigned long saved_ksp_limit;
+};
+
+/* ensure this structure is always sized to a multiple of the stack alignment */
+#define STACK_EXC_LVL_FRAME_SIZE _ALIGN_UP(sizeof (struct exception_regs), 16)
+
+#endif /* __ASSEMBLY__ */
+#endif /* __HEAD_BOOKE_H__ */
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