[PATCH] ppc32: Add support for Freescale e200 (Book-E) core

The e200 core is a Book-E core (similar to e500) that has a unified L1 cache
and is not cache coherent on the bus.  The e200 core also adds a separate
exception level for debug exceptions.  Part of this patch helps to cleanup a
few cases that are true for all Freescale Book-E parts, not just e500.

Signed-off-by: Kim Phillips <kim.phillips@freescale.com>
Signed-off-by: Kumar Gala <kumar.gala@freescale.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

8 files changed, 179 insertions, 6 deletions

diff --git a/arch/ppc/kernel/Makefile b/arch/ppc/kernel/Makefile
index b284451802c9..8276c0b551d2 100644
--- a/arch/ppc/kernel/Makefile
+++ b/arch/ppc/kernel/Makefile
@@ -26,7 +26,9 @@ obj-$(CONFIG_KGDB)		+= ppc-stub.o
 obj-$(CONFIG_SMP)		+= smp.o smp-tbsync.o
 obj-$(CONFIG_TAU)		+= temp.o
 obj-$(CONFIG_ALTIVEC)		+= vecemu.o vector.o
+ifndef CONFIG_E200
 obj-$(CONFIG_FSL_BOOKE)		+= perfmon_fsl_booke.o
+endif
 
 ifndef CONFIG_MATH_EMULATION
 obj-$(CONFIG_8xx)		+= softemu8xx.o
diff --git a/arch/ppc/kernel/cputable.c b/arch/ppc/kernel/cputable.c
index 01c226008dbf..50936cda0af9 100644
--- a/arch/ppc/kernel/cputable.c
+++ b/arch/ppc/kernel/cputable.c
@@ -903,7 +903,30 @@ struct cpu_spec	cpu_specs[] = {
 		.dcache_bsize		= 32,
 	},
 #endif /* CONFIG_44x */
-#ifdef CONFIG_E500
+#ifdef CONFIG_FSL_BOOKE
+	{ 	/* e200z5 */
+		.pvr_mask		= 0xfff00000,
+		.pvr_value		= 0x81000000,
+		.cpu_name		= "e200z5",
+		/* xxx - galak: add CPU_FTR_MAYBE_CAN_DOZE */
+		.cpu_features		= CPU_FTR_USE_TB,
+		.cpu_user_features	= PPC_FEATURE_32 |
+			PPC_FEATURE_HAS_MMU | PPC_FEATURE_HAS_EFP_SINGLE |
+			PPC_FEATURE_UNIFIED_CACHE,
+		.dcache_bsize		= 32,
+	},
+	{ 	/* e200z6 */
+		.pvr_mask		= 0xfff00000,
+		.pvr_value		= 0x81100000,
+		.cpu_name		= "e200z6",
+		/* xxx - galak: add CPU_FTR_MAYBE_CAN_DOZE */
+		.cpu_features		= CPU_FTR_USE_TB,
+		.cpu_user_features	= PPC_FEATURE_32 |
+			PPC_FEATURE_HAS_MMU | PPC_FEATURE_SPE_COMP |
+			PPC_FEATURE_HAS_EFP_SINGLE |
+			PPC_FEATURE_UNIFIED_CACHE,
+		.dcache_bsize		= 32,
+	},
 	{ 	/* e500 */
 		.pvr_mask		= 0xffff0000,
 		.pvr_value		= 0x80200000,
diff --git a/arch/ppc/kernel/entry.S b/arch/ppc/kernel/entry.S
index 8377b6ca26da..d4df68629cc6 100644
--- a/arch/ppc/kernel/entry.S
+++ b/arch/ppc/kernel/entry.S
@@ -60,6 +60,11 @@ mcheck_transfer_to_handler:
 	TRANSFER_TO_HANDLER_EXC_LEVEL(MCHECK)
 	b	transfer_to_handler_full
 
+	.globl	debug_transfer_to_handler
+debug_transfer_to_handler:
+	TRANSFER_TO_HANDLER_EXC_LEVEL(DEBUG)
+	b	transfer_to_handler_full
+
 	.globl	crit_transfer_to_handler
 crit_transfer_to_handler:
 	TRANSFER_TO_HANDLER_EXC_LEVEL(CRIT)
@@ -835,6 +840,10 @@ ret_from_crit_exc:
 	RET_FROM_EXC_LEVEL(SPRN_CSRR0, SPRN_CSRR1, RFCI)
 
 #ifdef CONFIG_BOOKE
+	.globl	ret_from_debug_exc
+ret_from_debug_exc:
+	RET_FROM_EXC_LEVEL(SPRN_DSRR0, SPRN_DSRR1, RFDI)
+
 	.globl	ret_from_mcheck_exc
 ret_from_mcheck_exc:
 	RET_FROM_EXC_LEVEL(SPRN_MCSRR0, SPRN_MCSRR1, RFMCI)
diff --git a/arch/ppc/kernel/head_booke.h b/arch/ppc/kernel/head_booke.h
index 9c50f9d2657c..9342acf12e72 100644
--- a/arch/ppc/kernel/head_booke.h
+++ b/arch/ppc/kernel/head_booke.h
@@ -49,6 +49,7 @@
  *
  * 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
@@ -60,12 +61,16 @@
 
 /* CRIT_SPRG only used in critical exception handling */
 #define CRIT_SPRG	SPRN_SPRG2
-/* MCHECK_SPRG only used in critical exception handling */
+/* MCHECK_SPRG only used in machine check exception handling */
 #define MCHECK_SPRG	SPRN_SPRG6W
 
 #define MCHECK_STACK_TOP	(exception_stack_top - 4096)
 #define CRIT_STACK_TOP		(exception_stack_top)
 
+/* only on e200 for now */
+#define DEBUG_STACK_TOP		(exception_stack_top - 4096)
+#define DEBUG_SPRG		SPRN_SPRG6W
+
 #ifdef CONFIG_SMP
 #define BOOKE_LOAD_EXC_LEVEL_STACK(level)		\
 	mfspr	r8,SPRN_PIR;				\
@@ -124,6 +129,8 @@
 
 #define CRITICAL_EXCEPTION_PROLOG \
 		EXC_LEVEL_EXCEPTION_PROLOG(CRIT, SPRN_CSRR0, SPRN_CSRR1)
+#define DEBUG_EXCEPTION_PROLOG \
+		EXC_LEVEL_EXCEPTION_PROLOG(DEBUG, SPRN_DSRR0, SPRN_DSRR1)
 #define MCHECK_EXCEPTION_PROLOG \
 		EXC_LEVEL_EXCEPTION_PROLOG(MCHECK, SPRN_MCSRR0, SPRN_MCSRR1)
 
@@ -205,6 +212,60 @@ label:
  * save (and later restore) the MSR via SPRN_CSRR1, which will still have
  * the MSR_DE bit set.
  */
+#ifdef CONFIG_E200
+#define DEBUG_EXCEPTION							      \
+	START_EXCEPTION(Debug);						      \
+	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 CSRR1 value and clearing the debug status.	      \
+	 */								      \
+	mfspr	r10,SPRN_DBSR;		/* check single-step/branch taken */  \
+	andis.	r10,r10,DBSR_IC@h;					      \
+	beq+	2f;							      \
+									      \
+	lis	r10,KERNELBASE@h;	/* check if exception in vectors */   \
+	ori	r10,r10,KERNELBASE@l;					      \
+	cmplw	r12,r10;						      \
+	blt+	2f;			/* addr below exception vectors */    \
+									      \
+	lis	r10,Debug@h;						      \
+	ori	r10,r10,Debug@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@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	DEBUG_SPRG,r8;						      \
+	BOOKE_LOAD_EXC_LEVEL_STACK(DEBUG); /* r8 points to the debug stack */ \
+	lwz	r10,GPR10-INT_FRAME_SIZE(r8);				      \
+	lwz	r11,GPR11-INT_FRAME_SIZE(r8);				      \
+	mfspr	r8,DEBUG_SPRG;						      \
+									      \
+	RFDI;								      \
+	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, debug_transfer_to_handler, ret_from_debug_exc)
+#else
 #define DEBUG_EXCEPTION							      \
 	START_EXCEPTION(Debug);						      \
 	CRITICAL_EXCEPTION_PROLOG;					      \
@@ -257,6 +318,7 @@ label:
 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)
+#endif
 
 #define INSTRUCTION_STORAGE_EXCEPTION					      \
 	START_EXCEPTION(InstructionStorage)				      \
diff --git a/arch/ppc/kernel/head_fsl_booke.S b/arch/ppc/kernel/head_fsl_booke.S
index ce36e88ba627..eb804b7a3cb2 100644
--- a/arch/ppc/kernel/head_fsl_booke.S
+++ b/arch/ppc/kernel/head_fsl_booke.S
@@ -102,6 +102,7 @@ invstr:	mflr	r6				/* Make it accessible */
 	or	r7,r7,r4
 	mtspr	SPRN_MAS6,r7
 	tlbsx	0,r6				/* search MSR[IS], SPID=PID0 */
+#ifndef CONFIG_E200
 	mfspr	r7,SPRN_MAS1
 	andis.	r7,r7,MAS1_VALID@h
 	bne	match_TLB
@@ -118,6 +119,7 @@ invstr:	mflr	r6				/* Make it accessible */
 	or	r7,r7,r4
 	mtspr	SPRN_MAS6,r7
 	tlbsx	0,r6				/* Fall through, we had to match */
+#endif
 match_TLB:
 	mfspr	r7,SPRN_MAS0
 	rlwinm	r3,r7,16,20,31			/* Extract MAS0(Entry) */
@@ -196,8 +198,10 @@ skpinv:	addi	r6,r6,1				/* Increment */
 /* 4. Clear out PIDs & Search info */
 	li	r6,0
 	mtspr	SPRN_PID0,r6
+#ifndef CONFIG_E200
 	mtspr	SPRN_PID1,r6
 	mtspr	SPRN_PID2,r6
+#endif
 	mtspr	SPRN_MAS6,r6
 
 /* 5. Invalidate mapping we started in */
@@ -277,7 +281,9 @@ skpinv:	addi	r6,r6,1				/* Increment */
 	SET_IVOR(32, SPEUnavailable);
 	SET_IVOR(33, SPEFloatingPointData);
 	SET_IVOR(34, SPEFloatingPointRound);
+#ifndef CONFIG_E200
 	SET_IVOR(35, PerformanceMonitor);
+#endif
 
 	/* Establish the interrupt vector base */
 	lis	r4,interrupt_base@h	/* IVPR only uses the high 16-bits */
@@ -285,6 +291,9 @@ skpinv:	addi	r6,r6,1				/* Increment */
 
 	/* Setup the defaults for TLB entries */
 	li	r2,(MAS4_TSIZED(BOOKE_PAGESZ_4K))@l
+#ifdef CONFIG_E200
+	oris	r2,r2,MAS4_TLBSELD(1)@h
+#endif
    	mtspr	SPRN_MAS4, r2
 
 #if 0
@@ -293,6 +302,12 @@ skpinv:	addi	r6,r6,1				/* Increment */
 	oris	r2,r2,HID0_DOZE@h
 	mtspr	SPRN_HID0, r2
 #endif
+#ifdef CONFIG_E200
+	/* enable dedicated debug exception handling resources (Debug APU) */
+	mfspr	r2,SPRN_HID0
+	ori 	r2,r2,HID0_DAPUEN@l
+	mtspr	SPRN_HID0,r2
+#endif
 
 #if !defined(CONFIG_BDI_SWITCH)
 	/*
@@ -414,7 +429,12 @@ interrupt_base:
 	CRITICAL_EXCEPTION(0x0100, CriticalInput, UnknownException)
 
 	/* Machine Check Interrupt */
+#ifdef CONFIG_E200
+	/* no RFMCI, MCSRRs on E200 */
+	CRITICAL_EXCEPTION(0x0200, MachineCheck, MachineCheckException)
+#else
 	MCHECK_EXCEPTION(0x0200, MachineCheck, MachineCheckException)
+#endif
 
 	/* Data Storage Interrupt */
 	START_EXCEPTION(DataStorage)
@@ -520,8 +540,13 @@ interrupt_base:
 #ifdef CONFIG_PPC_FPU
 	FP_UNAVAILABLE_EXCEPTION
 #else
+#ifdef CONFIG_E200
+	/* E200 treats 'normal' floating point instructions as FP Unavail exception */
+	EXCEPTION(0x0800, FloatingPointUnavailable, ProgramCheckException, EXC_XFER_EE)
+#else
 	EXCEPTION(0x0800, FloatingPointUnavailable, UnknownException, EXC_XFER_EE)
 #endif
+#endif
 
 	/* System Call Interrupt */
 	START_EXCEPTION(SystemCall)
@@ -691,6 +716,7 @@ interrupt_base:
 /*
  * Local functions
  */
+
 	/*
 	 * Data TLB exceptions will bail out to this point
 	 * if they can't resolve the lightweight TLB fault.
@@ -761,6 +787,31 @@ END_FTR_SECTION_IFSET(CPU_FTR_BIG_PHYS)
 2:	rlwimi	r11, r12, 0, 20, 31	/* Extract RPN from PTE and merge with perms */
 	mtspr	SPRN_MAS3, r11
 #endif
+#ifdef CONFIG_E200
+	/* Round robin TLB1 entries assignment */
+	mfspr	r12, SPRN_MAS0
+
+	/* Extract TLB1CFG(NENTRY) */
+	mfspr	r11, SPRN_TLB1CFG
+	andi.	r11, r11, 0xfff
+
+	/* Extract MAS0(NV) */
+	andi.	r13, r12, 0xfff
+	addi	r13, r13, 1
+	cmpw	0, r13, r11
+	addi	r12, r12, 1
+
+	/* check if we need to wrap */
+	blt	7f
+
+	/* wrap back to first free tlbcam entry */
+	lis	r13, tlbcam_index@ha
+	lwz	r13, tlbcam_index@l(r13)
+	rlwimi	r12, r13, 0, 20, 31
+7:
+	mtspr   SPRN_MAS0,r12
+#endif /* CONFIG_E200 */
+
 	tlbwe
 
 	/* Done...restore registers and get out of here.  */
diff --git a/arch/ppc/kernel/misc.S b/arch/ppc/kernel/misc.S
index 7329ef177a18..a3132f8e799c 100644
--- a/arch/ppc/kernel/misc.S
+++ b/arch/ppc/kernel/misc.S
@@ -593,6 +593,14 @@ _GLOBAL(flush_instruction_cache)
 	iccci	0,r3
 #endif
 #elif CONFIG_FSL_BOOKE
+BEGIN_FTR_SECTION
+	mfspr   r3,SPRN_L1CSR0
+	ori     r3,r3,L1CSR0_CFI|L1CSR0_CLFC
+	/* msync; isync recommended here */
+	mtspr   SPRN_L1CSR0,r3
+	isync
+	blr
+END_FTR_SECTION_IFCLR(CPU_FTR_SPLIT_ID_CACHE)
 	mfspr	r3,SPRN_L1CSR1
 	ori	r3,r3,L1CSR1_ICFI|L1CSR1_ICLFR
 	mtspr	SPRN_L1CSR1,r3
diff --git a/arch/ppc/kernel/perfmon.c b/arch/ppc/kernel/perfmon.c
index 918f6b252e45..fa1dad96b830 100644
--- a/arch/ppc/kernel/perfmon.c
+++ b/arch/ppc/kernel/perfmon.c
@@ -36,7 +36,7 @@
 /* A lock to regulate grabbing the interrupt */
 DEFINE_SPINLOCK(perfmon_lock);
 
-#ifdef CONFIG_FSL_BOOKE
+#if defined (CONFIG_FSL_BOOKE) && !defined (CONFIG_E200)
 static void dummy_perf(struct pt_regs *regs)
 {
 	unsigned int pmgc0 = mfpmr(PMRN_PMGC0);
diff --git a/arch/ppc/kernel/traps.c b/arch/ppc/kernel/traps.c
index 2ca8ecfeefd9..9e6ae5696650 100644
--- a/arch/ppc/kernel/traps.c
+++ b/arch/ppc/kernel/traps.c
@@ -173,13 +173,13 @@ static inline int check_io_access(struct pt_regs *regs)
 /* On 4xx, the reason for the machine check or program exception
    is in the ESR. */
 #define get_reason(regs)	((regs)->dsisr)
-#ifndef CONFIG_E500
+#ifndef CONFIG_FSL_BOOKE
 #define get_mc_reason(regs)	((regs)->dsisr)
 #else
 #define get_mc_reason(regs)	(mfspr(SPRN_MCSR))
 #endif
 #define REASON_FP		ESR_FP
-#define REASON_ILLEGAL		ESR_PIL
+#define REASON_ILLEGAL		(ESR_PIL | ESR_PUO)
 #define REASON_PRIVILEGED	ESR_PPR
 #define REASON_TRAP		ESR_PTR
 
@@ -302,7 +302,25 @@ void MachineCheckException(struct pt_regs *regs)
 		printk("Bus - Instruction Parity Error\n");
 	if (reason & MCSR_BUS_RPERR)
 		printk("Bus - Read Parity Error\n");
-#else /* !CONFIG_4xx && !CONFIG_E500 */
+#elif defined (CONFIG_E200)
+	printk("Machine check in kernel mode.\n");
+	printk("Caused by (from MCSR=%lx): ", reason);
+
+	if (reason & MCSR_MCP)
+		printk("Machine Check Signal\n");
+	if (reason & MCSR_CP_PERR)
+		printk("Cache Push Parity Error\n");
+	if (reason & MCSR_CPERR)
+		printk("Cache Parity Error\n");
+	if (reason & MCSR_EXCP_ERR)
+		printk("ISI, ITLB, or Bus Error on first instruction fetch for an exception handler\n");
+	if (reason & MCSR_BUS_IRERR)
+		printk("Bus - Read Bus Error on instruction fetch\n");
+	if (reason & MCSR_BUS_DRERR)
+		printk("Bus - Read Bus Error on data load\n");
+	if (reason & MCSR_BUS_WRERR)
+		printk("Bus - Write Bus Error on buffered store or cache line push\n");
+#else /* !CONFIG_4xx && !CONFIG_E500 && !CONFIG_E200 */
 	printk("Machine check in kernel mode.\n");
 	printk("Caused by (from SRR1=%lx): ", reason);
 	switch (reason & 0x601F0000) {