Commit 795033c3 authored by Dave Kleikamp's avatar Dave Kleikamp Committed by Josh Boyer
Browse files

powerpc/44x: break out cpu init code into stand-alone function 



The 47x platform supports multiple cores and shares code with 44x.
Break out code that is common for initializing the primary and secondary
cpus into a function which can be called for both.

Signed-off-by: default avatarDave Kleikamp <shaggy@linux.vnet.ibm.com>
Signed-off-by: default avatarJosh Boyer <jwboyer@linux.vnet.ibm.com>
parent 471c70ff

arch/powerpc/kernel/head_44x.S

+171 −159
Original line number Diff line number Diff line
@@ -69,165 +69,7 @@ _ENTRY(_start); 
	mr	r27,r7

	li	r24,0		/* CPU number */



/*

 * In case the firmware didn't do it, we apply some workarounds

 * that are good for all 440 core variants here

 */

	mfspr	r3,SPRN_CCR0

	rlwinm	r3,r3,0,0,27	/* disable icache prefetch */

	isync

	mtspr	SPRN_CCR0,r3

	isync

	sync



/*

 * Set up the initial MMU state

 *

 * We are still executing code at the virtual address

 * mappings set by the firmware for the base of RAM.

 *

 * We first invalidate all TLB entries but the one

 * we are running from.  We then load the KERNELBASE

 * mappings so we can begin to use kernel addresses

 * natively and so the interrupt vector locations are

 * permanently pinned (necessary since Book E

 * implementations always have translation enabled).

 *

 * TODO: Use the known TLB entry we are running from to

 *	 determine which physical region we are located

 *	 in.  This can be used to determine where in RAM

 *	 (on a shared CPU system) or PCI memory space

 *	 (on a DRAMless system) we are located.

 *       For now, we assume a perfect world which means

 *	 we are located at the base of DRAM (physical 0).

 */



/*

 * Search TLB for entry that we are currently using.

 * Invalidate all entries but the one we are using.

 */

	/* Load our current PID->MMUCR TID and MSR IS->MMUCR STS */

	mfspr	r3,SPRN_PID			/* Get PID */

	mfmsr	r4				/* Get MSR */

	andi.	r4,r4,MSR_IS@l			/* TS=1? */

	beq	wmmucr				/* If not, leave STS=0 */

	oris	r3,r3,PPC44x_MMUCR_STS@h	/* Set STS=1 */

wmmucr:	mtspr	SPRN_MMUCR,r3			/* Put MMUCR */

	sync



	bl	invstr				/* Find our address */

invstr:	mflr	r5				/* Make it accessible */

	tlbsx	r23,0,r5			/* Find entry we are in */

	li	r4,0				/* Start at TLB entry 0 */

	li	r3,0				/* Set PAGEID inval value */

1:	cmpw	r23,r4				/* Is this our entry? */

	beq	skpinv				/* If so, skip the inval */

	tlbwe	r3,r4,PPC44x_TLB_PAGEID		/* If not, inval the entry */

skpinv:	addi	r4,r4,1				/* Increment */

	cmpwi	r4,64				/* Are we done? */

	bne	1b				/* If not, repeat */

	isync					/* If so, context change */



/*

 * Configure and load pinned entry into TLB slot 63.

 */



	lis	r3,PAGE_OFFSET@h

	ori	r3,r3,PAGE_OFFSET@l



	/* Kernel is at the base of RAM */

	li r4, 0			/* Load the kernel physical address */



	/* Load the kernel PID = 0 */

	li	r0,0

	mtspr	SPRN_PID,r0

	sync



	/* Initialize MMUCR */

	li	r5,0

	mtspr	SPRN_MMUCR,r5

	sync



 	/* pageid fields */

	clrrwi	r3,r3,10		/* Mask off the effective page number */

	ori	r3,r3,PPC44x_TLB_VALID | PPC44x_TLB_256M



	/* xlat fields */

	clrrwi	r4,r4,10		/* Mask off the real page number */

					/* ERPN is 0 for first 4GB page */



	/* attrib fields */

	/* Added guarded bit to protect against speculative loads/stores */

	li	r5,0

	ori	r5,r5,(PPC44x_TLB_SW | PPC44x_TLB_SR | PPC44x_TLB_SX | PPC44x_TLB_G)



        li      r0,63                    /* TLB slot 63 */



	tlbwe	r3,r0,PPC44x_TLB_PAGEID	/* Load the pageid fields */

	tlbwe	r4,r0,PPC44x_TLB_XLAT	/* Load the translation fields */

	tlbwe	r5,r0,PPC44x_TLB_ATTRIB	/* Load the attrib/access fields */



	/* Force context change */

	mfmsr	r0

	mtspr	SPRN_SRR1, r0

	lis	r0,3f@h

	ori	r0,r0,3f@l

	mtspr	SPRN_SRR0,r0

	sync

	rfi



	/* If necessary, invalidate original entry we used */

3:	cmpwi	r23,63

	beq	4f

	li	r6,0

	tlbwe   r6,r23,PPC44x_TLB_PAGEID

	isync



4:

#ifdef CONFIG_PPC_EARLY_DEBUG_44x

	/* Add UART mapping for early debug. */



 	/* pageid fields */

	lis	r3,PPC44x_EARLY_DEBUG_VIRTADDR@h

	ori	r3,r3,PPC44x_TLB_VALID|PPC44x_TLB_TS|PPC44x_TLB_64K



	/* xlat fields */

	lis	r4,CONFIG_PPC_EARLY_DEBUG_44x_PHYSLOW@h

	ori	r4,r4,CONFIG_PPC_EARLY_DEBUG_44x_PHYSHIGH



	/* attrib fields */

	li	r5,(PPC44x_TLB_SW|PPC44x_TLB_SR|PPC44x_TLB_I|PPC44x_TLB_G)

        li      r0,62                    /* TLB slot 0 */



	tlbwe	r3,r0,PPC44x_TLB_PAGEID

	tlbwe	r4,r0,PPC44x_TLB_XLAT

	tlbwe	r5,r0,PPC44x_TLB_ATTRIB



	/* Force context change */

	isync

#endif /* CONFIG_PPC_EARLY_DEBUG_44x */



	/* Establish the interrupt vector offsets */

	SET_IVOR(0,  CriticalInput);

	SET_IVOR(1,  MachineCheck);

	SET_IVOR(2,  DataStorage);

	SET_IVOR(3,  InstructionStorage);

	SET_IVOR(4,  ExternalInput);

	SET_IVOR(5,  Alignment);

	SET_IVOR(6,  Program);

	SET_IVOR(7,  FloatingPointUnavailable);

	SET_IVOR(8,  SystemCall);

	SET_IVOR(9,  AuxillaryProcessorUnavailable);

	SET_IVOR(10, Decrementer);

	SET_IVOR(11, FixedIntervalTimer);

	SET_IVOR(12, WatchdogTimer);

	SET_IVOR(13, DataTLBError);

	SET_IVOR(14, InstructionTLBError);

	SET_IVOR(15, DebugCrit);



	/* Establish the interrupt vector base */

	lis	r4,interrupt_base@h	/* IVPR only uses the high 16-bits */

	mtspr	SPRN_IVPR,r4

	bl	init_cpu_state



	/*

	 * This is where the main kernel code starts.
@@ -646,6 +488,176 @@ _GLOBAL(set_context) 
	isync			/* Force context change */

	blr



/*

 * Init CPU state. This is called at boot time or for secondary CPUs

 * to setup initial TLB entries, setup IVORs, etc...

 */

_GLOBAL(init_cpu_state)

	mflr	r22

/*

 * In case the firmware didn't do it, we apply some workarounds

 * that are good for all 440 core variants here

 */

	mfspr	r3,SPRN_CCR0

	rlwinm	r3,r3,0,0,27	/* disable icache prefetch */

	isync

	mtspr	SPRN_CCR0,r3

	isync

	sync



/*

 * Set up the initial MMU state

 *

 * We are still executing code at the virtual address

 * mappings set by the firmware for the base of RAM.

 *

 * We first invalidate all TLB entries but the one

 * we are running from.  We then load the KERNELBASE

 * mappings so we can begin to use kernel addresses

 * natively and so the interrupt vector locations are

 * permanently pinned (necessary since Book E

 * implementations always have translation enabled).

 *

 * TODO: Use the known TLB entry we are running from to

 *	 determine which physical region we are located

 *	 in.  This can be used to determine where in RAM

 *	 (on a shared CPU system) or PCI memory space

 *	 (on a DRAMless system) we are located.

 *       For now, we assume a perfect world which means

 *	 we are located at the base of DRAM (physical 0).

 */



/*

 * Search TLB for entry that we are currently using.

 * Invalidate all entries but the one we are using.

 */

	/* Load our current PID->MMUCR TID and MSR IS->MMUCR STS */

	mfspr	r3,SPRN_PID			/* Get PID */

	mfmsr	r4				/* Get MSR */

	andi.	r4,r4,MSR_IS@l			/* TS=1? */

	beq	wmmucr				/* If not, leave STS=0 */

	oris	r3,r3,PPC44x_MMUCR_STS@h	/* Set STS=1 */

wmmucr:	mtspr	SPRN_MMUCR,r3			/* Put MMUCR */

	sync



	bl	invstr				/* Find our address */

invstr:	mflr	r5				/* Make it accessible */

	tlbsx	r23,0,r5			/* Find entry we are in */

	li	r4,0				/* Start at TLB entry 0 */

	li	r3,0				/* Set PAGEID inval value */

1:	cmpw	r23,r4				/* Is this our entry? */

	beq	skpinv				/* If so, skip the inval */

	tlbwe	r3,r4,PPC44x_TLB_PAGEID		/* If not, inval the entry */

skpinv:	addi	r4,r4,1				/* Increment */

	cmpwi	r4,64				/* Are we done? */

	bne	1b				/* If not, repeat */

	isync					/* If so, context change */



/*

 * Configure and load pinned entry into TLB slot 63.

 */



	lis	r3,PAGE_OFFSET@h

	ori	r3,r3,PAGE_OFFSET@l



	/* Kernel is at the base of RAM */

	li r4, 0			/* Load the kernel physical address */



	/* Load the kernel PID = 0 */

	li	r0,0

	mtspr	SPRN_PID,r0

	sync



	/* Initialize MMUCR */

	li	r5,0

	mtspr	SPRN_MMUCR,r5

	sync



	/* pageid fields */

	clrrwi	r3,r3,10		/* Mask off the effective page number */

	ori	r3,r3,PPC44x_TLB_VALID | PPC44x_TLB_256M



	/* xlat fields */

	clrrwi	r4,r4,10		/* Mask off the real page number */

					/* ERPN is 0 for first 4GB page */



	/* attrib fields */

	/* Added guarded bit to protect against speculative loads/stores */

	li	r5,0

	ori	r5,r5,(PPC44x_TLB_SW | PPC44x_TLB_SR | PPC44x_TLB_SX | PPC44x_TLB_G)



        li      r0,63                    /* TLB slot 63 */



	tlbwe	r3,r0,PPC44x_TLB_PAGEID	/* Load the pageid fields */

	tlbwe	r4,r0,PPC44x_TLB_XLAT	/* Load the translation fields */

	tlbwe	r5,r0,PPC44x_TLB_ATTRIB	/* Load the attrib/access fields */



	/* Force context change */

	mfmsr	r0

	mtspr	SPRN_SRR1, r0

	lis	r0,3f@h

	ori	r0,r0,3f@l

	mtspr	SPRN_SRR0,r0

	sync

	rfi



	/* If necessary, invalidate original entry we used */

3:	cmpwi	r23,63

	beq	4f

	li	r6,0

	tlbwe   r6,r23,PPC44x_TLB_PAGEID

	isync



4:

#ifdef CONFIG_PPC_EARLY_DEBUG_44x

	/* Add UART mapping for early debug. */



	/* pageid fields */

	lis	r3,PPC44x_EARLY_DEBUG_VIRTADDR@h

	ori	r3,r3,PPC44x_TLB_VALID|PPC44x_TLB_TS|PPC44x_TLB_64K



	/* xlat fields */

	lis	r4,CONFIG_PPC_EARLY_DEBUG_44x_PHYSLOW@h

	ori	r4,r4,CONFIG_PPC_EARLY_DEBUG_44x_PHYSHIGH



	/* attrib fields */

	li	r5,(PPC44x_TLB_SW|PPC44x_TLB_SR|PPC44x_TLB_I|PPC44x_TLB_G)

        li      r0,62                    /* TLB slot 0 */



	tlbwe	r3,r0,PPC44x_TLB_PAGEID

	tlbwe	r4,r0,PPC44x_TLB_XLAT

	tlbwe	r5,r0,PPC44x_TLB_ATTRIB



	/* Force context change */

	isync

#endif /* CONFIG_PPC_EARLY_DEBUG_44x */



	/* Establish the interrupt vector offsets */

	SET_IVOR(0,  CriticalInput);

	SET_IVOR(1,  MachineCheck);

	SET_IVOR(2,  DataStorage);

	SET_IVOR(3,  InstructionStorage);

	SET_IVOR(4,  ExternalInput);

	SET_IVOR(5,  Alignment);

	SET_IVOR(6,  Program);

	SET_IVOR(7,  FloatingPointUnavailable);

	SET_IVOR(8,  SystemCall);

	SET_IVOR(9,  AuxillaryProcessorUnavailable);

	SET_IVOR(10, Decrementer);

	SET_IVOR(11, FixedIntervalTimer);

	SET_IVOR(12, WatchdogTimer);

	SET_IVOR(13, DataTLBError);

	SET_IVOR(14, InstructionTLBError);

	SET_IVOR(15, DebugCrit);



	/* Establish the interrupt vector base */

	lis	r4,interrupt_base@h	/* IVPR only uses the high 16-bits */

	mtspr	SPRN_IVPR,r4



	addis	r22,r22,KERNELBASE@h

	mtlr	r22

	blr



/*

 * We put a few things here that have to be page-aligned. This stuff

 * goes at the beginning of the data segment, which is page-aligned.