From: "Steven J. Hill" <sjhill@xxxxxxxx>
All exceptions must be taken in microMIPS mode, never in MIPS32R2
mode or the kernel falls apart. A few 'nop' instructions are used
to maintain the correct alignment of microMIPS versions of the
exception vectors.
Signed-off-by: Steven J. Hill <sjhill@xxxxxxxx>
---
arch/mips/include/asm/mipsregs.h | 1 +
arch/mips/include/asm/stackframe.h | 12 +-
arch/mips/kernel/cpu-probe.c | 3 +
arch/mips/kernel/genex.S | 78 +++++++---
arch/mips/kernel/scall32-o32.S | 18 ++-
arch/mips/kernel/smtc-asm.S | 3 +
arch/mips/kernel/traps.c | 300 ++++++++++++++++++++++++++-----------
arch/mips/mm/tlbex.c | 21 +++
arch/mips/mti-sead3/sead3-init.c | 48 ++++++
9 files changed, 370 insertions(+), 114 deletions(-)
diff --git a/arch/mips/include/asm/mipsregs.h b/arch/mips/include/asm/mipsregs.h
index 1b8db8d..7695edb 100644
--- a/arch/mips/include/asm/mipsregs.h
+++ b/arch/mips/include/asm/mipsregs.h
@@ -592,6 +592,7 @@
#define MIPS_CONF3_DSP (_ULCAST_(1) << 10)
#define MIPS_CONF3_ULRI (_ULCAST_(1) << 13)
#define MIPS_CONF3_ISA (_ULCAST_(3) << 14)
+#define MIPS_CONF3_ISA_OE (_ULCAST_(1) << 16)
#define MIPS_CONF4_MMUSIZEEXT (_ULCAST_(255) << 0)
#define MIPS_CONF4_MMUEXTDEF (_ULCAST_(3) << 14)
diff --git a/arch/mips/include/asm/stackframe.h b/arch/mips/include/asm/stackframe.h
index cb41af5..335ce06 100644
--- a/arch/mips/include/asm/stackframe.h
+++ b/arch/mips/include/asm/stackframe.h
@@ -139,7 +139,7 @@
1: move ra, k0
li k0, 3
mtc0 k0, $22
-#endif /* CONFIG_CPU_LOONGSON2F */
+#endif /* CONFIG_CPU_JUMP_WORKAROUNDS */
#if defined(CONFIG_32BIT) || defined(KBUILD_64BIT_SYM32)
lui k1, %hi(kernelsp)
#else
@@ -189,6 +189,7 @@
LONG_S $0, PT_R0(sp)
mfc0 v1, CP0_STATUS
LONG_S $2, PT_R2(sp)
+ LONG_S v1, PT_STATUS(sp)
#ifdef CONFIG_MIPS_MT_SMTC
/*
* Ideally, these instructions would be shuffled in
@@ -200,21 +201,20 @@
LONG_S k0, PT_TCSTATUS(sp)
#endif /* CONFIG_MIPS_MT_SMTC */
LONG_S $4, PT_R4(sp)
- LONG_S $5, PT_R5(sp)
- LONG_S v1, PT_STATUS(sp)
mfc0 v1, CP0_CAUSE
- LONG_S $6, PT_R6(sp)
- LONG_S $7, PT_R7(sp)
+ LONG_S $5, PT_R5(sp)
LONG_S v1, PT_CAUSE(sp)
+ LONG_S $6, PT_R6(sp)
MFC0 v1, CP0_EPC
+ LONG_S $7, PT_R7(sp)
#ifdef CONFIG_64BIT
LONG_S $8, PT_R8(sp)
LONG_S $9, PT_R9(sp)
#endif
+ LONG_S v1, PT_EPC(sp)
LONG_S $25, PT_R25(sp)
LONG_S $28, PT_R28(sp)
LONG_S $31, PT_R31(sp)
- LONG_S v1, PT_EPC(sp)
ori $28, sp, _THREAD_MASK
xori $28, _THREAD_MASK
#ifdef CONFIG_CPU_CAVIUM_OCTEON
diff --git a/arch/mips/kernel/cpu-probe.c b/arch/mips/kernel/cpu-probe.c
index f3f42d7..4842870 100644
--- a/arch/mips/kernel/cpu-probe.c
+++ b/arch/mips/kernel/cpu-probe.c
@@ -745,6 +745,9 @@ static inline unsigned int decode_config3(struct cpuinfo_mips *c)
c->options |= MIPS_CPU_ULRI;
if (config3 & MIPS_CONF3_ISA)
c->options |= MIPS_CPU_MICROMIPS;
+#ifdef CONFIG_CPU_MICROMIPS
+ write_c0_config3(read_c0_config3() | MIPS_CONF3_ISA_OE);
+#endif
return config3 & MIPS_CONF_M;
}
diff --git a/arch/mips/kernel/genex.S b/arch/mips/kernel/genex.S
index 8882e57..3494d68 100644
--- a/arch/mips/kernel/genex.S
+++ b/arch/mips/kernel/genex.S
@@ -5,8 +5,8 @@
*
* Copyright (C) 1994 - 2000, 2001, 2003 Ralf Baechle
* Copyright (C) 1999, 2000 Silicon Graphics, Inc.
- * Copyright (C) 2001 MIPS Technologies, Inc.
* Copyright (C) 2002, 2007 Maciej W. Rozycki
+ * Copyright (C) 2001, 2012 MIPS Technologies, Inc. All rights reserved.
*/
#include <linux/init.h>
@@ -22,8 +22,10 @@
#include <asm/page.h>
#include <asm/thread_info.h>
+#ifdef CONFIG_MIPS_MT_SMTC
#define PANIC_PIC(msg) \
- .set push; \
+ .set push; \
+ .set nomicromips; \
.set reorder; \
PTR_LA a0,8f; \
.set noat; \
@@ -32,17 +34,10 @@
9: b 9b; \
.set pop; \
TEXT(msg)
+#endif
__INIT
-NESTED(except_vec0_generic, 0, sp)
- PANIC_PIC("Exception vector 0 called")
- END(except_vec0_generic)
-
-NESTED(except_vec1_generic, 0, sp)
- PANIC_PIC("Exception vector 1 called")
- END(except_vec1_generic)
-
/*
* General exception vector for all other CPUs.
*
@@ -65,6 +60,7 @@ NESTED(except_vec3_generic, 0, sp)
.set pop
END(except_vec3_generic)
+#if (cpu_has_vce != 0)
/*
* General exception handler for CPUs with virtual coherency exception.
*
@@ -124,6 +120,7 @@ handle_vcei:
eret
.set pop
END(except_vec3_r4000)
+#endif /* (cpu_has_vce == 0) */
__FINIT
@@ -139,12 +136,19 @@ LEAF(r4k_wait)
nop
nop
nop
+#ifdef CONFIG_CPU_MICROMIPS
+ nop
+ nop
+ nop
+ nop
+#endif
.set mips3
wait
/* end of rollback region (the region size must be power of two) */
- .set pop
1:
jr ra
+ nop
+ .set pop
END(r4k_wait)
.macro BUILD_ROLLBACK_PROLOGUE handler
@@ -202,7 +206,11 @@ NESTED(handle_int, PT_SIZE, sp)
LONG_L s0, TI_REGS($28)
LONG_S sp, TI_REGS($28)
PTR_LA ra, ret_from_irq
- j plat_irq_dispatch
+ PTR_LA v0, plat_irq_dispatch
+ jr v0
+#ifdef CONFIG_CPU_MICROMIPS
+ nop
+#endif
END(handle_int)
__INIT
@@ -223,11 +231,14 @@ NESTED(except_vec4, 0, sp)
/*
* EJTAG debug exception handler.
* The EJTAG debug exception entry point is 0xbfc00480, which
- * normally is in the boot PROM, so the boot PROM must do a
+ * normally is in the boot PROM, so the boot PROM must do an
* unconditional jump to this vector.
*/
NESTED(except_vec_ejtag_debug, 0, sp)
j ejtag_debug_handler
+#ifdef CONFIG_CPU_MICROMIPS
+ nop
+#endif
END(except_vec_ejtag_debug)
__FINIT
@@ -252,9 +263,10 @@ NESTED(except_vec_vi, 0, sp)
FEXPORT(except_vec_vi_mori)
ori a0, $0, 0
#endif /* CONFIG_MIPS_MT_SMTC */
+ PTR_LA v1, except_vec_vi_handler
FEXPORT(except_vec_vi_lui)
lui v0, 0 /* Patched */
- j except_vec_vi_handler
+ jr v1
FEXPORT(except_vec_vi_ori)
ori v0, 0 /* Patched */
.set pop
@@ -355,6 +367,9 @@ EXPORT(ejtag_debug_buffer)
*/
NESTED(except_vec_nmi, 0, sp)
j nmi_handler
+#ifdef CONFIG_CPU_MICROMIPS
+ nop
+#endif
END(except_vec_nmi)
__FINIT
@@ -363,7 +378,7 @@ NESTED(nmi_handler, PT_SIZE, sp)
.set push
.set noat
SAVE_ALL
- move a0, sp
+ move a0, sp
jal nmi_exception_handler
RESTORE_ALL
.set mips3
@@ -501,13 +516,36 @@ NESTED(nmi_handler, PT_SIZE, sp)
.set push
.set noat
.set noreorder
- /* 0x7c03e83b: rdhwr v1,$29 */
+ /* MIPS32: 0x7c03e83b: rdhwr v1,$29 */
+ /* uMIPS: 0x007d6b3c: rdhwr v1,$29 -- in MIPS16e it is */
+ /* ADDIUSP $16,0x7d; LI $3,0x3c and never RI. LY22 */
MFC0 k1, CP0_EPC
- lui k0, 0x7c03
- lw k1, (k1)
- ori k0, 0xe83b
- .set reorder
+#if defined(CONFIG_CPU_MICROMIPS) || defined(CONFIG_CPU_MIPS32_R2) || defined(CONFIG_CPU_MIPS64_R2)
+ and k0, k1, 1
+ beqz k0, 1f
+ xor k1, k0
+ lhu k0, (k1)
+ lhu k1, 2(k1)
+ ins k1, k0, 16, 16
+ lui k0, 0x007d
+ b docheck
+ ori k0, 0x6b3c
+1:
+ lui k0, 0x7c03
+ lw k1, (k1)
+ ori k0, 0xe83b
+#else
+ andi k0, k1, 1
+ bnez k0, handle_ri
+ lui k0, 0x7c03
+ lw k1, (k1)
+ ori k0, 0xe83b
+#endif
+ .set reorder
+docheck:
bne k0, k1, handle_ri /* if not ours */
+
+isrdhwr:
/* The insn is rdhwr. No need to check CAUSE.BD here. */
get_saved_sp /* k1 := current_thread_info */
.set noreorder
diff --git a/arch/mips/kernel/scall32-o32.S b/arch/mips/kernel/scall32-o32.S
index a632bc1..bcb6982f 100644
--- a/arch/mips/kernel/scall32-o32.S
+++ b/arch/mips/kernel/scall32-o32.S
@@ -143,15 +143,25 @@ stackargs:
jr t1
addiu t1, 6f - 5f
-2: lw t8, 28(t0) # argument #8 from usp
-3: lw t7, 24(t0) # argument #7 from usp
-4: lw t6, 20(t0) # argument #6 from usp
-5: jr t1
+ lw t8, 28(t0) # argument #8 from usp
+ lw t7, 24(t0) # argument #7 from usp
+ lw t6, 20(t0) # argument #6 from usp
+ jr t1
sw t5, 16(sp) # argument #5 to ksp
+#ifdef CONFIG_CPU_MICROMIPS
+ ## FIXME:
+ sw t8, 28(sp) # argument #8 to ksp
+ nop
+ sw t7, 24(sp) # argument #7 to ksp
+ nop
+ sw t6, 20(sp) # argument #6 to ksp
+ nop
+#else
sw t8, 28(sp) # argument #8 to ksp
sw t7, 24(sp) # argument #7 to ksp
sw t6, 20(sp) # argument #6 to ksp
+#endif
6: j stack_done # go back
nop
.set pop
diff --git a/arch/mips/kernel/smtc-asm.S b/arch/mips/kernel/smtc-asm.S
index 20938a4..8e9ae50 100644
--- a/arch/mips/kernel/smtc-asm.S
+++ b/arch/mips/kernel/smtc-asm.S
@@ -49,6 +49,9 @@ CAN WE PROVE THAT WE WON'T DO THIS IF INTS DISABLED??
.text
.align 5
FEXPORT(__smtc_ipi_vector)
+#ifdef CONFIG_CPU_MICROMIPS
+ nop
+#endif
.set noat
/* Disable thread scheduling to make Status update atomic */
DMT 27 # dmt k1
diff --git a/arch/mips/kernel/traps.c b/arch/mips/kernel/traps.c
index 8322ce9..3d76ece 100644
--- a/arch/mips/kernel/traps.c
+++ b/arch/mips/kernel/traps.c
@@ -8,8 +8,8 @@
* Copyright (C) 1998 Ulf Carlsson
* Copyright (C) 1999 Silicon Graphics, Inc.
* Kevin D. Kissell, kevink@xxxxxxxx and Carsten Langgaard, carstenl@xxxxxxxx
- * Copyright (C) 2000, 01 MIPS Technologies, Inc.
* Copyright (C) 2002, 2003, 2004, 2005, 2007 Maciej W. Rozycki
+ * Copyright (C) 2000, 2001, 2012 MIPS Technologies, Inc. All rights reserved.
*/
#include <linux/bug.h>
#include <linux/compiler.h>
@@ -82,10 +82,6 @@ extern asmlinkage void handle_dsp(void);
extern asmlinkage void handle_mcheck(void);
extern asmlinkage void handle_reserved(void);
-extern int fpu_emulator_cop1Handler(struct pt_regs *xcp,
- struct mips_fpu_struct *ctx, int has_fpu,
- void *__user *fault_addr);
-
void (*board_be_init)(void);
int (*board_be_handler)(struct pt_regs *regs, int is_fixup);
void (*board_nmi_handler_setup)(void);
@@ -491,6 +487,12 @@ asmlinkage void do_be(struct pt_regs *regs)
#define SYNC 0x0000000f
#define RDHWR 0x0000003b
+/* microMIPS definitions */
+#define MM_POOL32A_FUNC 0xfc00ffff
+#define MM_RDHWR 0x00006b3c
+#define MM_RS 0x001f0000
+#define MM_RT 0x03e00000
+
/*
* The ll_bit is cleared by r*_switch.S
*/
@@ -605,42 +607,62 @@ static int simulate_llsc(struct pt_regs *regs, unsigned int opcode)
* Simulate trapping 'rdhwr' instructions to provide user accessible
* registers not implemented in hardware.
*/
-static int simulate_rdhwr(struct pt_regs *regs, unsigned int opcode)
+static int simulate_rdhwr(struct pt_regs *regs, int rd, int rt)
{
struct thread_info *ti = task_thread_info(current);
+ perf_sw_event(PERF_COUNT_SW_EMULATION_FAULTS,
+ 1, regs, 0);
+ switch (rd) {
+ case 0: /* CPU number */
+ regs->regs[rt] = smp_processor_id();
+ return 0;
+ case 1: /* SYNCI length */
+ regs->regs[rt] = min(current_cpu_data.dcache.linesz,
+ current_cpu_data.icache.linesz);
+ return 0;
+ case 2: /* Read count register */
+ regs->regs[rt] = read_c0_count();
+ return 0;
+ case 3: /* Count register resolution */
+ switch (current_cpu_data.cputype) {
+ case CPU_20KC:
+ case CPU_25KF:
+ regs->regs[rt] = 1;
+ break;
+ default:
+ regs->regs[rt] = 2;
+ }
+ return 0;
+ case 29:
+ regs->regs[rt] = ti->tp_value;
+ return 0;
+ default:
+ return -1;
+ }
+}
+
+static int simulate_rdhwr_normal(struct pt_regs *regs, unsigned int opcode)
+{
if ((opcode & OPCODE) == SPEC3 && (opcode & FUNC) == RDHWR) {
int rd = (opcode & RD) >> 11;
int rt = (opcode & RT) >> 16;
- perf_sw_event(PERF_COUNT_SW_EMULATION_FAULTS,
- 1, regs, 0);
- switch (rd) {
- case 0: /* CPU number */
- regs->regs[rt] = smp_processor_id();
- return 0;
- case 1: /* SYNCI length */
- regs->regs[rt] = min(current_cpu_data.dcache.linesz,
- current_cpu_data.icache.linesz);
- return 0;
- case 2: /* Read count register */
- regs->regs[rt] = read_c0_count();
- return 0;
- case 3: /* Count register resolution */
- switch (current_cpu_data.cputype) {
- case CPU_20KC:
- case CPU_25KF:
- regs->regs[rt] = 1;
- break;
- default:
- regs->regs[rt] = 2;
- }
- return 0;
- case 29:
- regs->regs[rt] = ti->tp_value;
- return 0;
- default:
- return -1;
- }
+
+ simulate_rdhwr(regs, rd, rt);
+ return 0;
+ }
+
+ /* Not ours. */
+ return -1;
+}
+
+static int simulate_rdhwr_mm(struct pt_regs *regs, unsigned short opcode)
+{
+ if ((opcode & MM_POOL32A_FUNC) == MM_RDHWR) {
+ int rd = (opcode & MM_RS) >> 16;
+ int rt = (opcode & MM_RT) >> 21;
+ simulate_rdhwr(regs, rd, rt);
+ return 0;
}
/* Not ours. */
@@ -671,7 +693,7 @@ asmlinkage void do_ov(struct pt_regs *regs)
force_sig_info(SIGFPE, &info, current);
}
-static int process_fpemu_return(int sig, void __user *fault_addr)
+int process_fpemu_return(int sig, void __user *fault_addr)
{
if (sig == SIGSEGV || sig == SIGBUS) {
struct siginfo si = {0};
@@ -797,6 +819,7 @@ static void do_trap_or_bp(struct pt_regs *regs, unsigned int code,
die_if_kernel("Kernel bug detected", regs);
force_sig(SIGTRAP, current);
break;
+ case MM_BRK_MEMU:
case BRK_MEMU:
/*
* Address errors may be deliberately induced by the FPU
@@ -822,9 +845,29 @@ static void do_trap_or_bp(struct pt_regs *regs, unsigned int code,
asmlinkage void do_bp(struct pt_regs *regs)
{
unsigned int opcode, bcode;
-
- if (__get_user(opcode, (unsigned int __user *) exception_epc(regs)))
- goto out_sigsegv;
+ unsigned long epc;
+ u16 instr[2];
+
+ if (regs->cp0_epc & MIPS_ISA_MODE) {
+ /* calc exception pc */
+ epc = exception_epc(regs);
+ if (cpu_has_mmips) {
+ if ((__get_user(instr[0], (u16 __user *)(epc & ~MIPS_ISA_MODE))) ||
+ (__get_user(instr[1], (u16 __user *)((epc+2) & ~MIPS_ISA_MODE))))
+ goto out_sigsegv;
+ opcode = (instr[0] << 16) | instr[1];
+ } else {
+ /* MIPS16e mode */
+ if (__get_user(instr[0], (u16 __user *)(epc & ~MIPS_ISA_MODE)))
+ goto out_sigsegv;
+ bcode = (instr[0] >> 6) & 0x3f;
+ do_trap_or_bp(regs, bcode, "Break");
+ return;
+ }
+ } else {
+ if (__get_user(opcode, (unsigned int __user *) exception_epc(regs)))
+ goto out_sigsegv;
+ }
/*
* There is the ancient bug in the MIPS assemblers that the break
@@ -865,13 +908,22 @@ out_sigsegv:
asmlinkage void do_tr(struct pt_regs *regs)
{
unsigned int opcode, tcode = 0;
+ u16 instr[2];
+ unsigned long epc = exception_epc(regs);
- if (__get_user(opcode, (unsigned int __user *) exception_epc(regs)))
- goto out_sigsegv;
+ if ((__get_user(instr[0], (u16 __user *)(epc & ~MIPS_ISA_MODE))) ||
+ (__get_user(instr[1], (u16 __user *)((epc+2) & ~MIPS_ISA_MODE))))
+ goto out_sigsegv;
+ opcode = (instr[0] << 16) | instr[1];
/* Immediate versions don't provide a code. */
- if (!(opcode & OPCODE))
- tcode = ((opcode >> 6) & ((1 << 10) - 1));
+ if (!(opcode & OPCODE)) {
+ if (is16mode(regs))
+ /* microMIPS */
+ tcode = (opcode >> 12) & 0x1f;
+ else
+ tcode = ((opcode >> 6) & ((1 << 10) - 1));
+ }
do_trap_or_bp(regs, tcode, "Trap");
return;
@@ -884,6 +936,7 @@ asmlinkage void do_ri(struct pt_regs *regs)
{
unsigned int __user *epc = (unsigned int __user *)exception_epc(regs);
unsigned long old_epc = regs->cp0_epc;
+ unsigned long old31 = regs->regs[31];
unsigned int opcode = 0;
int status = -1;
@@ -896,23 +949,37 @@ asmlinkage void do_ri(struct pt_regs *regs)
if (unlikely(compute_return_epc(regs) < 0))
return;
- if (unlikely(get_user(opcode, epc) < 0))
- status = SIGSEGV;
+ if (is16mode(regs)) {
+ unsigned short mmop[2] = { 0 };
- if (!cpu_has_llsc && status < 0)
- status = simulate_llsc(regs, opcode);
+ if (unlikely(get_user(mmop[0], epc) < 0))
+ status = SIGSEGV;
+ if (unlikely(get_user(mmop[1], epc) < 0))
+ status = SIGSEGV;
+ opcode = (mmop[0] << 16) | mmop[1];
- if (status < 0)
- status = simulate_rdhwr(regs, opcode);
+ if (status < 0)
+ status = simulate_rdhwr_mm(regs, opcode);
+ } else {
+ if (unlikely(get_user(opcode, epc) < 0))
+ status = SIGSEGV;
- if (status < 0)
- status = simulate_sync(regs, opcode);
+ if (!cpu_has_llsc && status < 0)
+ status = simulate_llsc(regs, opcode);
+
+ if (status < 0)
+ status = simulate_rdhwr_normal(regs, opcode);
+
+ if (status < 0)
+ status = simulate_sync(regs, opcode);
+ }
if (status < 0)
status = SIGILL;
if (unlikely(status > 0)) {
regs->cp0_epc = old_epc; /* Undo skip-over. */
+ regs->regs[31] = old31;
force_sig(status, current);
}
}
@@ -982,7 +1049,7 @@ static int default_cu2_call(struct notifier_block *nfb, unsigned long action,
asmlinkage void do_cpu(struct pt_regs *regs)
{
unsigned int __user *epc;
- unsigned long old_epc;
+ unsigned long old_epc, old31;
unsigned int opcode;
unsigned int cpid;
int status;
@@ -996,26 +1063,41 @@ asmlinkage void do_cpu(struct pt_regs *regs)
case 0:
epc = (unsigned int __user *)exception_epc(regs);
old_epc = regs->cp0_epc;
+ old31 = regs->regs[31];
opcode = 0;
status = -1;
if (unlikely(compute_return_epc(regs) < 0))
return;
- if (unlikely(get_user(opcode, epc) < 0))
- status = SIGSEGV;
+ if (is16mode(regs)) {
+ unsigned short mmop[2] = { 0 };
- if (!cpu_has_llsc && status < 0)
- status = simulate_llsc(regs, opcode);
+ if (unlikely(get_user(mmop[0], epc) < 0))
+ status = SIGSEGV;
+ if (unlikely(get_user(mmop[1], epc) < 0))
+ status = SIGSEGV;
+ opcode = (mmop[0] << 16) | mmop[1];
- if (status < 0)
- status = simulate_rdhwr(regs, opcode);
+ if (status < 0)
+ status = simulate_rdhwr_mm(regs, opcode);
+ } else {
+ if (unlikely(get_user(opcode, epc) < 0))
+ status = SIGSEGV;
+
+ if (!cpu_has_llsc && status < 0)
+ status = simulate_llsc(regs, opcode);
+
+ if (status < 0)
+ status = simulate_rdhwr_normal(regs, opcode);
+ }
if (status < 0)
status = SIGILL;
if (unlikely(status > 0)) {
regs->cp0_epc = old_epc; /* Undo skip-over. */
+ regs->regs[31] = old31;
force_sig(status, current);
}
@@ -1328,7 +1410,7 @@ asmlinkage void cache_parity_error(void)
void ejtag_exception_handler(struct pt_regs *regs)
{
const int field = 2 * sizeof(unsigned long);
- unsigned long depc, old_epc;
+ unsigned long depc, old_epc, old_ra;
unsigned int debug;
printk(KERN_DEBUG "SDBBP EJTAG debug exception - not handled yet, just ignored!\n");
@@ -1343,10 +1425,12 @@ void ejtag_exception_handler(struct pt_regs *regs)
* calculation.
*/
old_epc = regs->cp0_epc;
+ old_ra = regs->regs[31];
regs->cp0_epc = depc;
- __compute_return_epc(regs);
+ compute_return_epc(regs);
depc = regs->cp0_epc;
regs->cp0_epc = old_epc;
+ regs->regs[31] = old_ra;
} else
depc += 4;
write_c0_depc(depc);
@@ -1387,9 +1471,24 @@ void __init *set_except_vector(int n, void *addr)
unsigned long handler = (unsigned long) addr;
unsigned long old_handler = exception_handlers[n];
+#ifdef CONFIG_CPU_MICROMIPS
+ /*
+ * Only the TLB handlers are cache aligned with an even
+ * address. All other handlers are on an odd address and
+ * require no modification. Otherwise, MIPS32 mode will
+ * be entered when handling any TLB exceptions. That
+ * would be bad...since we must stay in microMIPS mode.
+ */
+ if (!(handler & 0x1))
+ handler |= 1;
+#endif
exception_handlers[n] = handler;
if (n == 0 && cpu_has_divec) {
+#ifdef CONFIG_CPU_MICROMIPS
+ unsigned long jump_mask = ~((1 << 27) - 1);
+#else
unsigned long jump_mask = ~((1 << 28) - 1);
+#endif
u32 *buf = (u32 *)(ebase + 0x200);
unsigned int k0 = 26;
if ((handler & jump_mask) == ((ebase + 0x200) & jump_mask)) {
@@ -1416,17 +1515,18 @@ static void *set_vi_srs_handler(int n, vi_handler_t addr, int srs)
unsigned long handler;
unsigned long old_handler = vi_handlers[n];
int srssets = current_cpu_data.srsets;
- u32 *w;
+ u16 *h;
unsigned char *b;
BUG_ON(!cpu_has_veic && !cpu_has_vint);
+ BUG_ON((n < 0) && (n > 9));
if (addr == NULL) {
handler = (unsigned long) do_default_vi;
srs = 0;
} else
handler = (unsigned long) addr;
- vi_handlers[n] = (unsigned long) addr;
+ vi_handlers[n] = handler;
b = (unsigned char *)(ebase + 0x200 + n*VECTORSPACING);
@@ -1445,9 +1545,8 @@ static void *set_vi_srs_handler(int n, vi_handler_t addr, int srs)
if (srs == 0) {
/*
* If no shadow set is selected then use the default handler
- * that does normal register saving and a standard interrupt exit
+ * that does normal register saving and standard interrupt exit
*/
-
extern char except_vec_vi, except_vec_vi_lui;
extern char except_vec_vi_ori, except_vec_vi_end;
extern char rollback_except_vec_vi;
@@ -1460,11 +1559,20 @@ static void *set_vi_srs_handler(int n, vi_handler_t addr, int srs)
* Status.IM bit to be masked before going there.
*/
extern char except_vec_vi_mori;
+#if defined(CONFIG_CPU_MICROMIPS) || defined(CONFIG_CPU_BIG_ENDIAN)
+ const int mori_offset = &except_vec_vi_mori - vec_start + 2;
+#else
const int mori_offset = &except_vec_vi_mori - vec_start;
+#endif
#endif /* CONFIG_MIPS_MT_SMTC */
- const int handler_len = &except_vec_vi_end - vec_start;
+#if defined(CONFIG_CPU_MICROMIPS) || defined(CONFIG_CPU_BIG_ENDIAN)
+ const int lui_offset = &except_vec_vi_lui - vec_start + 2;
+ const int ori_offset = &except_vec_vi_ori - vec_start + 2;
+#else
const int lui_offset = &except_vec_vi_lui - vec_start;
const int ori_offset = &except_vec_vi_ori - vec_start;
+#endif
+ const int handler_len = &except_vec_vi_end - vec_start;
if (handler_len > VECTORSPACING) {
/*
@@ -1474,30 +1582,44 @@ static void *set_vi_srs_handler(int n, vi_handler_t addr, int srs)
panic("VECTORSPACING too small");
}
- memcpy(b, vec_start, handler_len);
+ set_handler(((unsigned long)b - ebase), vec_start,
+#ifdef CONFIG_CPU_MICROMIPS
+ (handler_len - 1));
+#else
+ handler_len);
+#endif
#ifdef CONFIG_MIPS_MT_SMTC
BUG_ON(n > 7); /* Vector index %d exceeds SMTC maximum. */
- w = (u32 *)(b + mori_offset);
- *w = (*w & 0xffff0000) | (0x100 << n);
+ h = (u16 *)(b + mori_offset);
+ *h = (0x100 << n);
#endif /* CONFIG_MIPS_MT_SMTC */
- w = (u32 *)(b + lui_offset);
- *w = (*w & 0xffff0000) | (((u32)handler >> 16) & 0xffff);
- w = (u32 *)(b + ori_offset);
- *w = (*w & 0xffff0000) | ((u32)handler & 0xffff);
+ h = (u16 *)(b + lui_offset);
+ *h = (handler >> 16) & 0xffff;
+ h = (u16 *)(b + ori_offset);
+ *h = (handler & 0xffff);
local_flush_icache_range((unsigned long)b,
(unsigned long)(b+handler_len));
}
else {
/*
- * In other cases jump directly to the interrupt handler
- *
- * It is the handlers responsibility to save registers if required
- * (eg hi/lo) and return from the exception using "eret"
+ * In other cases jump directly to the interrupt handler. It
+ * is the handler's responsibility to save registers if required
+ * (eg hi/lo) and return from the exception using "eret".
*/
- w = (u32 *)b;
- *w++ = 0x08000000 | (((u32)handler >> 2) & 0x03fffff); /* j handler */
- *w = 0;
+ u32 insn;
+
+ h = (u16 *)b;
+ /* j handler */
+#ifdef CONFIG_CPU_MICROMIPS
+ insn = 0xd4000000 | (((u32)handler & 0x07ffffff) >> 1);
+#else
+ insn = 0x08000000 | (((u32)handler & 0x0fffffff) >> 2);
+#endif
+ h[0] = (insn >> 16) & 0xffff;
+ h[1] = insn & 0xffff;
+ h[2] = 0;
+ h[3] = 0;
local_flush_icache_range((unsigned long)b,
(unsigned long)(b+8));
}
@@ -1656,7 +1778,11 @@ void __cpuinit per_cpu_trap_init(bool is_boot_cpu)
/* Install CPU exception handler */
void __cpuinit set_handler(unsigned long offset, void *addr, unsigned long size)
{
+#ifdef CONFIG_CPU_MICROMIPS
+ memcpy((void *)(ebase + offset), ((unsigned char *)addr - 1), size);
+#else
memcpy((void *)(ebase + offset), addr, size);
+#endif
local_flush_icache_range(ebase + offset, ebase + offset + size);
}
@@ -1690,8 +1816,11 @@ __setup("rdhwr_noopt", set_rdhwr_noopt);
void __init trap_init(void)
{
- extern char except_vec3_generic, except_vec3_r4000;
+ extern char except_vec3_generic;
extern char except_vec4;
+#if (cpu_has_vce != 0)
+ extern char except_vec3_r4000;
+#endif
unsigned long i;
int rollback;
@@ -1822,13 +1951,16 @@ void __init trap_init(void)
if (board_cache_error_setup)
board_cache_error_setup();
+#if (cpu_has_vce != 0)
if (cpu_has_vce)
/* Special exception: R4[04]00 uses also the divec space. */
- memcpy((void *)(ebase + 0x180), &except_vec3_r4000, 0x100);
- else if (cpu_has_4kex)
- memcpy((void *)(ebase + 0x180), &except_vec3_generic, 0x80);
+ set_handler(0x180, &except_vec3_r4000, 0x100);
+ else
+#endif
+ if (cpu_has_4kex)
+ set_handler(0x180, &except_vec3_generic, 0x80);
else
- memcpy((void *)(ebase + 0x080), &except_vec3_generic, 0x80);
+ set_handler(0x080, &except_vec3_generic, 0x80);
local_flush_icache_range(ebase, ebase + 0x400);
flush_tlb_handlers();
diff --git a/arch/mips/mm/tlbex.c b/arch/mips/mm/tlbex.c
index 1566297..202908e 100644
--- a/arch/mips/mm/tlbex.c
+++ b/arch/mips/mm/tlbex.c
@@ -2012,6 +2012,13 @@ static void __cpuinit build_r4000_tlb_load_handler(void)
uasm_l_nopage_tlbl(&l, p);
build_restore_work_registers(&p);
+#ifdef CONFIG_CPU_MICROMIPS
+ if ((unsigned long)tlb_do_page_fault_0 & 1) {
+ uasm_i_lui(&p, K0, uasm_rel_hi((long)tlb_do_page_fault_0));
+ uasm_i_addiu(&p, K0, K0, uasm_rel_lo((long)tlb_do_page_fault_0));
+ uasm_i_jr(&p, K0);
+ } else
+#endif
uasm_i_j(&p, (unsigned long)tlb_do_page_fault_0 & 0x0fffffff);
uasm_i_nop(&p);
@@ -2059,6 +2066,13 @@ static void __cpuinit build_r4000_tlb_store_handler(void)
uasm_l_nopage_tlbs(&l, p);
build_restore_work_registers(&p);
+#ifdef CONFIG_CPU_MICROMIPS
+ if ((unsigned long)tlb_do_page_fault_1 & 1) {
+ uasm_i_lui(&p, K0, uasm_rel_hi((long)tlb_do_page_fault_1));
+ uasm_i_addiu(&p, K0, K0, uasm_rel_lo((long)tlb_do_page_fault_1));
+ uasm_i_jr(&p, K0);
+ } else
+#endif
uasm_i_j(&p, (unsigned long)tlb_do_page_fault_1 & 0x0fffffff);
uasm_i_nop(&p);
@@ -2107,6 +2121,13 @@ static void __cpuinit build_r4000_tlb_modify_handler(void)
uasm_l_nopage_tlbm(&l, p);
build_restore_work_registers(&p);
+#ifdef CONFIG_CPU_MICROMIPS
+ if ((unsigned long)tlb_do_page_fault_1 & 1) {
+ uasm_i_lui(&p, K0, uasm_rel_hi((long)tlb_do_page_fault_1));
+ uasm_i_addiu(&p, K0, K0, uasm_rel_lo((long)tlb_do_page_fault_1));
+ uasm_i_jr(&p, K0);
+ } else
+#endif
uasm_i_j(&p, (unsigned long)tlb_do_page_fault_1 & 0x0fffffff);
uasm_i_nop(&p);
diff --git a/arch/mips/mti-sead3/sead3-init.c b/arch/mips/mti-sead3/sead3-init.c
index 215b710..2d2f54b 100644
--- a/arch/mips/mti-sead3/sead3-init.c
+++ b/arch/mips/mti-sead3/sead3-init.c
@@ -131,7 +131,41 @@ static void __init mips_nmi_setup(void)
base = cpu_has_veic ?
(void *)(CAC_BASE + 0xa80) :
(void *)(CAC_BASE + 0x380);
+#ifdef CONFIG_CPU_MICROMIPS
+ /*
+ * Decrement the exception vector address by one for microMIPS.
+ */
+ memcpy(base, (&except_vec_nmi - 1), 0x80);
+
+ /*
+ * This is a hack. We do not know if the boot loader was built with
+ * microMIPS instructions or not. If it was not, the NMI exception
+ * code at 0x80000a80 will be taken in MIPS32 mode. The hand coded
+ * assembly below forces us into microMIPS mode if we are a pure
+ * microMIPS kernel. The assembly instructions are:
+ *
+ * 3C1A8000 lui k0,0x8000
+ * 375A0381 ori k0,k0,0x381
+ * 03400008 jr k0
+ * 00000000 nop
+ *
+ * The mode switch occurs by jumping to the unaligned exception
+ * vector address at 0x80000381 which would have been 0x80000380
+ * in MIPS32 mode. The jump to the unaligned address transitions
+ * us into microMIPS mode.
+ */
+ if (!cpu_has_veic) {
+ void *base2 = (void *)(CAC_BASE + 0xa80);
+ *((unsigned int *)base2) = 0x3c1a8000;
+ *((unsigned int *)base2 + 1) = 0x375a0381;
+ *((unsigned int *)base2 + 2) = 0x03400008;
+ *((unsigned int *)base2 + 3) = 0x00000000;
+ flush_icache_range((unsigned long)base2,
+ (unsigned long)base2 + 0x10);
+ }
+#else
memcpy(base, &except_vec_nmi, 0x80);
+#endif
flush_icache_range((unsigned long)base, (unsigned long)base + 0x80);
}
@@ -142,7 +176,21 @@ static void __init mips_ejtag_setup(void)
base = cpu_has_veic ?
(void *)(CAC_BASE + 0xa00) :
(void *)(CAC_BASE + 0x300);
+#ifdef CONFIG_CPU_MICROMIPS
+ /* Deja vu... */
+ memcpy(base, (&except_vec_ejtag_debug - 1), 0x80);
+ if (!cpu_has_veic) {
+ void *base2 = (void *)(CAC_BASE + 0xa00);
+ *((unsigned int *)base2) = 0x3c1a8000;
+ *((unsigned int *)base2 + 1) = 0x375a0301;
+ *((unsigned int *)base2 + 2) = 0x03400008;
+ *((unsigned int *)base2 + 3) = 0x00000000;
+ flush_icache_range((unsigned long)base2,
+ (unsigned long)base2 + 0x10);
+ }
+#else
memcpy(base, &except_vec_ejtag_debug, 0x80);
+#endif
flush_icache_range((unsigned long)base, (unsigned long)base + 0x80);
}
--
1.7.11.1
