[PATCH] ppc64: support 64k pages

Adds a new CONFIG_PPC_64K_PAGES which, when enabled, changes the kernel
base page size to 64K.  The resulting kernel still boots on any
hardware.  On current machines with 4K pages support only, the kernel
will maintain 16 "subpages" for each 64K page transparently.

Note that while real 64K capable HW has been tested, the current patch
will not enable it yet as such hardware is not released yet, and I'm
still verifying with the firmware architects the proper to get the
information from the newer hypervisors.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 586 insertions, 27 deletions

diff --git a/arch/powerpc/mm/hash_low_64.S b/arch/powerpc/mm/hash_low_64.S
index d6ed9102eeea..e0d02c4a2615 100644
--- a/arch/powerpc/mm/hash_low_64.S
+++ b/arch/powerpc/mm/hash_low_64.S
@@ -1,7 +1,7 @@
 /*
  * ppc64 MMU hashtable management routines
  *
- * (c) Copyright IBM Corp. 2003
+ * (c) Copyright IBM Corp. 2003, 2005
  *
  * Maintained by: Benjamin Herrenschmidt
  *                <benh@kernel.crashing.org>
@@ -10,6 +10,7 @@
  * described in the kernel's COPYING file.
  */
 
+#include <linux/config.h>
 #include <asm/reg.h>
 #include <asm/pgtable.h>
 #include <asm/mmu.h>
@@ -42,14 +43,24 @@
 /* Save non-volatile offsets */
 #define STK_REG(i)	(112 + ((i)-14)*8)
 
+
+#ifndef CONFIG_PPC_64K_PAGES
+
+/*****************************************************************************
+ *                                                                           *
+ *           4K SW & 4K HW pages implementation                              *
+ *                                                                           *
+ *****************************************************************************/
+
+
 /*
- * _hash_page(unsigned long ea, unsigned long access, unsigned long vsid,
- *		pte_t *ptep, unsigned long trap, int local)
+ * _hash_page_4K(unsigned long ea, unsigned long access, unsigned long vsid,
+ *		 pte_t *ptep, unsigned long trap, int local)
  *
- * Adds a page to the hash table. This is the non-LPAR version for now
+ * Adds a 4K page to the hash table in a segment of 4K pages only
  */
 
-_GLOBAL(__hash_page)
+_GLOBAL(__hash_page_4K)
 	mflr	r0
 	std	r0,16(r1)
 	stdu	r1,-STACKFRAMESIZE(r1)
@@ -88,7 +99,8 @@ _GLOBAL(__hash_page)
 	/* If so, just bail out and refault if needed. Someone else
 	 * is changing this PTE anyway and might hash it.
 	 */
-	bne-	bail_ok
+	bne-	htab_bail_ok
+
 	/* Prepare new PTE value (turn access RW into DIRTY, then
 	 * add BUSY,HASHPTE and ACCESSED)
 	 */
@@ -118,10 +130,10 @@ _GLOBAL(__hash_page)
 
 	/* Convert linux PTE bits into HW equivalents */
 	andi.	r3,r30,0x1fe		/* Get basic set of flags */
-	xori	r3,r3,HW_NO_EXEC	/* _PAGE_EXEC -> NOEXEC */
+	xori	r3,r3,HPTE_R_N		/* _PAGE_EXEC -> NOEXEC */
 	rlwinm	r0,r30,32-9+1,30,30	/* _PAGE_RW -> _PAGE_USER (r0) */
 	rlwinm	r4,r30,32-7+1,30,30	/* _PAGE_DIRTY -> _PAGE_USER (r4) */
-	and	r0,r0,r4		/* _PAGE_RW & _PAGE_DIRTY -> r0 bit 30 */
+	and	r0,r0,r4		/* _PAGE_RW & _PAGE_DIRTY ->r0 bit 30*/
 	andc	r0,r30,r0		/* r0 = pte & ~r0 */
 	rlwimi	r3,r0,32-1,31,31	/* Insert result into PP lsb */
 
@@ -158,19 +170,21 @@ htab_insert_pte:
 	andc	r30,r30,r0
 	ori	r30,r30,_PAGE_HASHPTE
 
-	/* page number in r5 */
-	rldicl	r5,r31,64-PTE_SHIFT,PTE_SHIFT
+	/* physical address r5 */
+	rldicl	r5,r31,64-PTE_RPN_SHIFT,PTE_RPN_SHIFT
+	sldi	r5,r5,PAGE_SHIFT
 
 	/* Calculate primary group hash */
 	and	r0,r28,r27
-	rldicr	r3,r0,3,63-3	/* r0 = (hash & mask) << 3 */
+	rldicr	r3,r0,3,63-3		/* r3 = (hash & mask) << 3 */
 
 	/* Call ppc_md.hpte_insert */
-	ld	r7,STK_PARM(r4)(r1)	/* Retreive new pp bits */
+	ld	r6,STK_PARM(r4)(r1)	/* Retreive new pp bits */
 	mr	r4,r29			/* Retreive va */
-	li	r6,0			/* no vflags */
+	li	r7,0			/* !bolted, !secondary */
+	li	r8,MMU_PAGE_4K		/* page size */
 _GLOBAL(htab_call_hpte_insert1)
-	bl	.			/* Will be patched by htab_finish_init() */
+	bl	.			/* Patched by htab_finish_init() */
 	cmpdi	0,r3,0
 	bge	htab_pte_insert_ok	/* Insertion successful */
 	cmpdi	0,r3,-2			/* Critical failure */
@@ -178,19 +192,21 @@ _GLOBAL(htab_call_hpte_insert1)
 
 	/* Now try secondary slot */
 	
-	/* page number in r5 */
-	rldicl	r5,r31,64-PTE_SHIFT,PTE_SHIFT
+	/* physical address r5 */
+	rldicl	r5,r31,64-PTE_RPN_SHIFT,PTE_RPN_SHIFT
+	sldi	r5,r5,PAGE_SHIFT
 
 	/* Calculate secondary group hash */
 	andc	r0,r27,r28
 	rldicr	r3,r0,3,63-3	/* r0 = (~hash & mask) << 3 */
 	
 	/* Call ppc_md.hpte_insert */
-	ld	r7,STK_PARM(r4)(r1)	/* Retreive new pp bits */
+	ld	r6,STK_PARM(r4)(r1)	/* Retreive new pp bits */
 	mr	r4,r29			/* Retreive va */
-	li	r6,HPTE_V_SECONDARY@l	/* secondary slot */
+	li	r7,HPTE_V_SECONDARY	/* !bolted, secondary */
+	li	r8,MMU_PAGE_4K		/* page size */
 _GLOBAL(htab_call_hpte_insert2)
-	bl	.			/* Will be patched by htab_finish_init() */
+	bl	.			/* Patched by htab_finish_init() */
 	cmpdi	0,r3,0
 	bge+	htab_pte_insert_ok	/* Insertion successful */
 	cmpdi	0,r3,-2			/* Critical failure */
@@ -207,14 +223,14 @@ _GLOBAL(htab_call_hpte_insert2)
 	rldicr	r3,r0,3,63-3	/* r0 = (hash & mask) << 3 */	
 	/* Call ppc_md.hpte_remove */
 _GLOBAL(htab_call_hpte_remove)
-	bl	.			/* Will be patched by htab_finish_init() */
+	bl	.			/* Patched by htab_finish_init() */
 
 	/* Try all again */
 	b	htab_insert_pte	
 
-bail_ok:
+htab_bail_ok:
 	li	r3,0
-	b	bail
+	b	htab_bail
 
 htab_pte_insert_ok:
 	/* Insert slot number & secondary bit in PTE */
@@ -227,7 +243,7 @@ htab_write_out_pte:
 	ld	r6,STK_PARM(r6)(r1)
 	std	r30,0(r6)
 	li	r3, 0
-bail:
+htab_bail:
 	ld	r27,STK_REG(r27)(r1)
 	ld	r28,STK_REG(r28)(r1)
 	ld	r29,STK_REG(r29)(r1)
@@ -256,10 +272,10 @@ htab_modify_pte:
 
 	/* Call ppc_md.hpte_updatepp */
 	mr	r5,r29			/* va */
-	li	r6,0			/* large is 0 */
+	li	r6,MMU_PAGE_4K		/* page size */
 	ld	r7,STK_PARM(r8)(r1)	/* get "local" param */
 _GLOBAL(htab_call_hpte_updatepp)
-	bl	.			/* Will be patched by htab_finish_init() */
+	bl	.			/* Patched by htab_finish_init() */
 
 	/* if we failed because typically the HPTE wasn't really here
 	 * we try an insertion. 
@@ -276,13 +292,556 @@ htab_wrong_access:
 	/* Bail out clearing reservation */
 	stdcx.	r31,0,r6
 	li	r3,1
-	b	bail
+	b	htab_bail
+
+htab_pte_insert_failure:
+	/* Bail out restoring old PTE */
+	ld	r6,STK_PARM(r6)(r1)
+	std	r31,0(r6)
+	li	r3,-1
+	b	htab_bail
+
+
+#else /* CONFIG_PPC_64K_PAGES */
+
+
+/*****************************************************************************
+ *                                                                           *
+ *           64K SW & 4K or 64K HW in a 4K segment pages implementation      *
+ *                                                                           *
+ *****************************************************************************/
+
+/* _hash_page_4K(unsigned long ea, unsigned long access, unsigned long vsid,
+ *		 pte_t *ptep, unsigned long trap, int local)
+ */
+
+/*
+ * For now, we do NOT implement Admixed pages
+ */
+_GLOBAL(__hash_page_4K)
+	mflr	r0
+	std	r0,16(r1)
+	stdu	r1,-STACKFRAMESIZE(r1)
+	/* Save all params that we need after a function call */
+	std	r6,STK_PARM(r6)(r1)
+	std	r8,STK_PARM(r8)(r1)
+
+	/* Add _PAGE_PRESENT to access */
+	ori	r4,r4,_PAGE_PRESENT
+
+	/* Save non-volatile registers.
+	 * r31 will hold "old PTE"
+	 * r30 is "new PTE"
+	 * r29 is "va"
+	 * r28 is a hash value
+	 * r27 is hashtab mask (maybe dynamic patched instead ?)
+	 * r26 is the hidx mask
+	 * r25 is the index in combo page
+	 */
+	std	r25,STK_REG(r25)(r1)
+	std	r26,STK_REG(r26)(r1)
+	std	r27,STK_REG(r27)(r1)
+	std	r28,STK_REG(r28)(r1)
+	std	r29,STK_REG(r29)(r1)
+	std	r30,STK_REG(r30)(r1)
+	std	r31,STK_REG(r31)(r1)
+
+	/* Step 1:
+	 *
+	 * Check permissions, atomically mark the linux PTE busy
+	 * and hashed.
+	 */
+1:
+	ldarx	r31,0,r6
+	/* Check access rights (access & ~(pte_val(*ptep))) */
+	andc.	r0,r4,r31
+	bne-	htab_wrong_access
+	/* Check if PTE is busy */
+	andi.	r0,r31,_PAGE_BUSY
+	/* If so, just bail out and refault if needed. Someone else
+	 * is changing this PTE anyway and might hash it.
+	 */
+	bne-	htab_bail_ok
+	/* Prepare new PTE value (turn access RW into DIRTY, then
+	 * add BUSY and ACCESSED)
+	 */
+	rlwinm	r30,r4,32-9+7,31-7,31-7	/* _PAGE_RW -> _PAGE_DIRTY */
+	or	r30,r30,r31
+	ori	r30,r30,_PAGE_BUSY | _PAGE_ACCESSED | _PAGE_HASHPTE
+	/* Write the linux PTE atomically (setting busy) */
+	stdcx.	r30,0,r6
+	bne-	1b
+	isync
+
+	/* Step 2:
+	 *
+	 * Insert/Update the HPTE in the hash table. At this point,
+	 * r4 (access) is re-useable, we use it for the new HPTE flags
+	 */
+
+	/* Load the hidx index */
+	rldicl	r25,r3,64-12,60
+
+	/* Calc va and put it in r29 */
+	rldicr	r29,r5,28,63-28		/* r29 = (vsid << 28) */
+	rldicl	r3,r3,0,36		/* r3 = (ea & 0x0fffffff) */
+	or	r29,r3,r29		/* r29 = va
+
+	/* Calculate hash value for primary slot and store it in r28 */
+	rldicl	r5,r5,0,25		/* vsid & 0x0000007fffffffff */
+	rldicl	r0,r3,64-12,48		/* (ea >> 12) & 0xffff */
+	xor	r28,r5,r0
+
+	/* Convert linux PTE bits into HW equivalents */
+	andi.	r3,r30,0x1fe		/* Get basic set of flags */
+	xori	r3,r3,HPTE_R_N		/* _PAGE_EXEC -> NOEXEC */
+	rlwinm	r0,r30,32-9+1,30,30	/* _PAGE_RW -> _PAGE_USER (r0) */
+	rlwinm	r4,r30,32-7+1,30,30	/* _PAGE_DIRTY -> _PAGE_USER (r4) */
+	and	r0,r0,r4		/* _PAGE_RW & _PAGE_DIRTY ->r0 bit 30*/
+	andc	r0,r30,r0		/* r0 = pte & ~r0 */
+	rlwimi	r3,r0,32-1,31,31	/* Insert result into PP lsb */
+
+	/* We eventually do the icache sync here (maybe inline that
+	 * code rather than call a C function...)
+	 */
+BEGIN_FTR_SECTION
+	mr	r4,r30
+	mr	r5,r7
+	bl	.hash_page_do_lazy_icache
+END_FTR_SECTION(CPU_FTR_NOEXECUTE|CPU_FTR_COHERENT_ICACHE, CPU_FTR_NOEXECUTE)
+
+	/* At this point, r3 contains new PP bits, save them in
+	 * place of "access" in the param area (sic)
+	 */
+	std	r3,STK_PARM(r4)(r1)
+
+	/* Get htab_hash_mask */
+	ld	r4,htab_hash_mask@got(2)
+	ld	r27,0(r4)	/* htab_hash_mask -> r27 */
+
+	/* Check if we may already be in the hashtable, in this case, we
+	 * go to out-of-line code to try to modify the HPTE. We look for
+	 * the bit at (1 >> (index + 32))
+	 */
+	andi.	r0,r31,_PAGE_HASHPTE
+	li	r26,0			/* Default hidx */
+	beq	htab_insert_pte
+	ld	r6,STK_PARM(r6)(r1)
+	ori	r26,r6,0x8000		/* Load the hidx mask */
+	ld	r26,0(r26)
+	addi	r5,r25,36		/* Check actual HPTE_SUB bit, this */
+	rldcr.	r0,r31,r5,0		/* must match pgtable.h definition */
+	bne	htab_modify_pte
+
+htab_insert_pte:
+	/* real page number in r5, PTE RPN value + index */
+	rldicl	r5,r31,64-PTE_RPN_SHIFT,PTE_RPN_SHIFT
+	sldi	r5,r5,PAGE_SHIFT-HW_PAGE_SHIFT
+	add	r5,r5,r25
+	sldi	r5,r5,HW_PAGE_SHIFT
+
+	/* Calculate primary group hash */
+	and	r0,r28,r27
+	rldicr	r3,r0,3,63-3		/* r0 = (hash & mask) << 3 */
+
+	/* Call ppc_md.hpte_insert */
+	ld	r6,STK_PARM(r4)(r1)	/* Retreive new pp bits */
+	mr	r4,r29			/* Retreive va */
+	li	r7,0			/* !bolted, !secondary */
+	li	r8,MMU_PAGE_4K		/* page size */
+_GLOBAL(htab_call_hpte_insert1)
+	bl	.			/* patched by htab_finish_init() */
+	cmpdi	0,r3,0
+	bge	htab_pte_insert_ok	/* Insertion successful */
+	cmpdi	0,r3,-2			/* Critical failure */
+	beq-	htab_pte_insert_failure
+
+	/* Now try secondary slot */
+
+	/* real page number in r5, PTE RPN value + index */
+	rldicl	r5,r31,64-PTE_RPN_SHIFT,PTE_RPN_SHIFT
+	sldi	r5,r5,PAGE_SHIFT-HW_PAGE_SHIFT
+	add	r5,r5,r25
+	sldi	r5,r5,HW_PAGE_SHIFT
+
+	/* Calculate secondary group hash */
+	andc	r0,r27,r28
+	rldicr	r3,r0,3,63-3		/* r0 = (~hash & mask) << 3 */
+
+	/* Call ppc_md.hpte_insert */
+	ld	r6,STK_PARM(r4)(r1)	/* Retreive new pp bits */
+	mr	r4,r29			/* Retreive va */
+	li	r7,HPTE_V_SECONDARY	/* !bolted, secondary */
+	li	r8,MMU_PAGE_4K		/* page size */
+_GLOBAL(htab_call_hpte_insert2)
+	bl	.			/* patched by htab_finish_init() */
+	cmpdi	0,r3,0
+	bge+	htab_pte_insert_ok	/* Insertion successful */
+	cmpdi	0,r3,-2			/* Critical failure */
+	beq-	htab_pte_insert_failure
+
+	/* Both are full, we need to evict something */
+	mftb	r0
+	/* Pick a random group based on TB */
+	andi.	r0,r0,1
+	mr	r5,r28
+	bne	2f
+	not	r5,r5
+2:	and	r0,r5,r27
+	rldicr	r3,r0,3,63-3		/* r0 = (hash & mask) << 3 */
+	/* Call ppc_md.hpte_remove */
+_GLOBAL(htab_call_hpte_remove)
+	bl	.			/* patched by htab_finish_init() */
+
+	/* Try all again */
+	b	htab_insert_pte
+
+htab_bail_ok:
+	li	r3,0
+	b	htab_bail
+
+htab_pte_insert_ok:
+	/* Insert slot number & secondary bit in PTE second half,
+	 * clear _PAGE_BUSY and set approriate HPTE slot bit
+	 */
+	ld	r6,STK_PARM(r6)(r1)
+	li	r0,_PAGE_BUSY
+	andc	r30,r30,r0
+	/* HPTE SUB bit */
+	li	r0,1
+	subfic	r5,r25,27		/* Must match bit position in */
+	sld	r0,r0,r5		/* pgtable.h */
+	or	r30,r30,r0
+	/* hindx */
+	sldi	r5,r25,2
+	sld	r3,r3,r5
+	li	r4,0xf
+	sld	r4,r4,r5
+	andc	r26,r26,r4
+	or	r26,r26,r3
+	ori	r5,r6,0x8000
+	std	r26,0(r5)
+	lwsync
+	std	r30,0(r6)
+	li	r3, 0
+htab_bail:
+	ld	r25,STK_REG(r25)(r1)
+	ld	r26,STK_REG(r26)(r1)
+	ld	r27,STK_REG(r27)(r1)
+	ld	r28,STK_REG(r28)(r1)
+	ld	r29,STK_REG(r29)(r1)
+	ld      r30,STK_REG(r30)(r1)
+	ld      r31,STK_REG(r31)(r1)
+	addi    r1,r1,STACKFRAMESIZE
+	ld      r0,16(r1)
+	mtlr    r0
+	blr
+
+htab_modify_pte:
+	/* Keep PP bits in r4 and slot idx from the PTE around in r3 */
+	mr	r4,r3
+	sldi	r5,r25,2
+	srd	r3,r26,r5
+
+	/* Secondary group ? if yes, get a inverted hash value */
+	mr	r5,r28
+	andi.	r0,r3,0x8 /* page secondary ? */
+	beq	1f
+	not	r5,r5
+1:	andi.	r3,r3,0x7 /* extract idx alone */
+
+	/* Calculate proper slot value for ppc_md.hpte_updatepp */
+	and	r0,r5,r27
+	rldicr	r0,r0,3,63-3	/* r0 = (hash & mask) << 3 */
+	add	r3,r0,r3	/* add slot idx */
+
+	/* Call ppc_md.hpte_updatepp */
+	mr	r5,r29			/* va */
+	li	r6,MMU_PAGE_4K		/* page size */
+	ld	r7,STK_PARM(r8)(r1)	/* get "local" param */
+_GLOBAL(htab_call_hpte_updatepp)
+	bl	.			/* patched by htab_finish_init() */
+
+	/* if we failed because typically the HPTE wasn't really here
+	 * we try an insertion.
+	 */
+	cmpdi	0,r3,-1
+	beq-	htab_insert_pte
+
+	/* Clear the BUSY bit and Write out the PTE */
+	li	r0,_PAGE_BUSY
+	andc	r30,r30,r0
+	ld	r6,STK_PARM(r6)(r1)
+	std	r30,0(r6)
+	li	r3,0
+	b	htab_bail
+
+htab_wrong_access:
+	/* Bail out clearing reservation */
+	stdcx.	r31,0,r6
+	li	r3,1
+	b	htab_bail
 
 htab_pte_insert_failure:
 	/* Bail out restoring old PTE */
 	ld	r6,STK_PARM(r6)(r1)
 	std	r31,0(r6)
 	li	r3,-1
-	b	bail
+	b	htab_bail
+
+
+/*****************************************************************************
+ *                                                                           *
+ *           64K SW & 64K HW in a 64K segment pages implementation           *
+ *                                                                           *
+ *****************************************************************************/
+
+_GLOBAL(__hash_page_64K)
+	mflr	r0
+	std	r0,16(r1)
+	stdu	r1,-STACKFRAMESIZE(r1)
+	/* Save all params that we need after a function call */
+	std	r6,STK_PARM(r6)(r1)
+	std	r8,STK_PARM(r8)(r1)
+
+	/* Add _PAGE_PRESENT to access */
+	ori	r4,r4,_PAGE_PRESENT
+
+	/* Save non-volatile registers.
+	 * r31 will hold "old PTE"
+	 * r30 is "new PTE"
+	 * r29 is "va"
+	 * r28 is a hash value
+	 * r27 is hashtab mask (maybe dynamic patched instead ?)
+	 */
+	std	r27,STK_REG(r27)(r1)
+	std	r28,STK_REG(r28)(r1)
+	std	r29,STK_REG(r29)(r1)
+	std	r30,STK_REG(r30)(r1)
+	std	r31,STK_REG(r31)(r1)
+
+	/* Step 1:
+	 *
+	 * Check permissions, atomically mark the linux PTE busy
+	 * and hashed.
+	 */
+1:
+	ldarx	r31,0,r6
+	/* Check access rights (access & ~(pte_val(*ptep))) */
+	andc.	r0,r4,r31
+	bne-	ht64_wrong_access
+	/* Check if PTE is busy */
+	andi.	r0,r31,_PAGE_BUSY
+	/* If so, just bail out and refault if needed. Someone else
+	 * is changing this PTE anyway and might hash it.
+	 */
+	bne-	ht64_bail_ok
+	/* Prepare new PTE value (turn access RW into DIRTY, then
+	 * add BUSY,HASHPTE and ACCESSED)
+	 */
+	rlwinm	r30,r4,32-9+7,31-7,31-7	/* _PAGE_RW -> _PAGE_DIRTY */
+	or	r30,r30,r31
+	ori	r30,r30,_PAGE_BUSY | _PAGE_ACCESSED | _PAGE_HASHPTE
+	/* Write the linux PTE atomically (setting busy) */
+	stdcx.	r30,0,r6
+	bne-	1b
+	isync
+
+	/* Step 2:
+	 *
+	 * Insert/Update the HPTE in the hash table. At this point,
+	 * r4 (access) is re-useable, we use it for the new HPTE flags
+	 */
+
+	/* Calc va and put it in r29 */
+	rldicr	r29,r5,28,63-28
+	rldicl	r3,r3,0,36
+	or	r29,r3,r29
+
+	/* Calculate hash value for primary slot and store it in r28 */
+	rldicl	r5,r5,0,25		/* vsid & 0x0000007fffffffff */
+	rldicl	r0,r3,64-16,52		/* (ea >> 16) & 0xfff */
+	xor	r28,r5,r0
+
+	/* Convert linux PTE bits into HW equivalents */
+	andi.	r3,r30,0x1fe		/* Get basic set of flags */
+	xori	r3,r3,HPTE_R_N		/* _PAGE_EXEC -> NOEXEC */
+	rlwinm	r0,r30,32-9+1,30,30	/* _PAGE_RW -> _PAGE_USER (r0) */
+	rlwinm	r4,r30,32-7+1,30,30	/* _PAGE_DIRTY -> _PAGE_USER (r4) */
+	and	r0,r0,r4		/* _PAGE_RW & _PAGE_DIRTY ->r0 bit 30*/
+	andc	r0,r30,r0		/* r0 = pte & ~r0 */
+	rlwimi	r3,r0,32-1,31,31	/* Insert result into PP lsb */
+
+	/* We eventually do the icache sync here (maybe inline that
+	 * code rather than call a C function...)
+	 */
+BEGIN_FTR_SECTION
+	mr	r4,r30
+	mr	r5,r7
+	bl	.hash_page_do_lazy_icache
+END_FTR_SECTION(CPU_FTR_NOEXECUTE|CPU_FTR_COHERENT_ICACHE, CPU_FTR_NOEXECUTE)
+
+	/* At this point, r3 contains new PP bits, save them in
+	 * place of "access" in the param area (sic)
+	 */
+	std	r3,STK_PARM(r4)(r1)
+
+	/* Get htab_hash_mask */
+	ld	r4,htab_hash_mask@got(2)
+	ld	r27,0(r4)	/* htab_hash_mask -> r27 */
+
+	/* Check if we may already be in the hashtable, in this case, we
+	 * go to out-of-line code to try to modify the HPTE
+	 */
+	andi.	r0,r31,_PAGE_HASHPTE
+	bne	ht64_modify_pte
+
+ht64_insert_pte:
+	/* Clear hpte bits in new pte (we also clear BUSY btw) and
+	 * add _PAGE_HASHPTE
+	 */
+	lis	r0,_PAGE_HPTEFLAGS@h
+	ori	r0,r0,_PAGE_HPTEFLAGS@l
+	andc	r30,r30,r0
+	ori	r30,r30,_PAGE_HASHPTE
+
+	/* Phyical address in r5 */
+	rldicl	r5,r31,64-PTE_RPN_SHIFT,PTE_RPN_SHIFT
+	sldi	r5,r5,PAGE_SHIFT
+
+	/* Calculate primary group hash */
+	and	r0,r28,r27
+	rldicr	r3,r0,3,63-3	/* r0 = (hash & mask) << 3 */
+
+	/* Call ppc_md.hpte_insert */
+	ld	r6,STK_PARM(r4)(r1)	/* Retreive new pp bits */
+	mr	r4,r29			/* Retreive va */
+	li	r7,0			/* !bolted, !secondary */
+	li	r8,MMU_PAGE_64K
+_GLOBAL(ht64_call_hpte_insert1)
+	bl	.			/* patched by htab_finish_init() */
+	cmpdi	0,r3,0
+	bge	ht64_pte_insert_ok	/* Insertion successful */
+	cmpdi	0,r3,-2			/* Critical failure */
+	beq-	ht64_pte_insert_failure
+
+	/* Now try secondary slot */
+
+	/* Phyical address in r5 */
+	rldicl	r5,r31,64-PTE_RPN_SHIFT,PTE_RPN_SHIFT
+	sldi	r5,r5,PAGE_SHIFT
+
+	/* Calculate secondary group hash */
+	andc	r0,r27,r28
+	rldicr	r3,r0,3,63-3	/* r0 = (~hash & mask) << 3 */
+
+	/* Call ppc_md.hpte_insert */
+	ld	r6,STK_PARM(r4)(r1)	/* Retreive new pp bits */
+	mr	r4,r29			/* Retreive va */
+	li	r7,HPTE_V_SECONDARY	/* !bolted, secondary */
+	li	r8,MMU_PAGE_64K
+_GLOBAL(ht64_call_hpte_insert2)
+	bl	.			/* patched by htab_finish_init() */
+	cmpdi	0,r3,0
+	bge+	ht64_pte_insert_ok	/* Insertion successful */
+	cmpdi	0,r3,-2			/* Critical failure */
+	beq-	ht64_pte_insert_failure
+
+	/* Both are full, we need to evict something */
+	mftb	r0
+	/* Pick a random group based on TB */
+	andi.	r0,r0,1
+	mr	r5,r28
+	bne	2f
+	not	r5,r5
+2:	and	r0,r5,r27
+	rldicr	r3,r0,3,63-3	/* r0 = (hash & mask) << 3 */
+	/* Call ppc_md.hpte_remove */
+_GLOBAL(ht64_call_hpte_remove)
+	bl	.			/* patched by htab_finish_init() */
+
+	/* Try all again */
+	b	ht64_insert_pte
+
+ht64_bail_ok:
+	li	r3,0
+	b	ht64_bail
+
+ht64_pte_insert_ok:
+	/* Insert slot number & secondary bit in PTE */
+	rldimi	r30,r3,12,63-15
+
+	/* Write out the PTE with a normal write
+	 * (maybe add eieio may be good still ?)
+	 */
+ht64_write_out_pte:
+	ld	r6,STK_PARM(r6)(r1)
+	std	r30,0(r6)
+	li	r3, 0
+ht64_bail:
+	ld	r27,STK_REG(r27)(r1)
+	ld	r28,STK_REG(r28)(r1)
+	ld	r29,STK_REG(r29)(r1)
+	ld      r30,STK_REG(r30)(r1)
+	ld      r31,STK_REG(r31)(r1)
+	addi    r1,r1,STACKFRAMESIZE
+	ld      r0,16(r1)
+	mtlr    r0
+	blr
+
+ht64_modify_pte:
+	/* Keep PP bits in r4 and slot idx from the PTE around in r3 */
+	mr	r4,r3
+	rlwinm	r3,r31,32-12,29,31
+
+	/* Secondary group ? if yes, get a inverted hash value */
+	mr	r5,r28
+	andi.	r0,r31,_PAGE_F_SECOND
+	beq	1f
+	not	r5,r5
+1:
+	/* Calculate proper slot value for ppc_md.hpte_updatepp */
+	and	r0,r5,r27
+	rldicr	r0,r0,3,63-3	/* r0 = (hash & mask) << 3 */
+	add	r3,r0,r3	/* add slot idx */
+
+	/* Call ppc_md.hpte_updatepp */
+	mr	r5,r29			/* va */
+	li	r6,MMU_PAGE_64K
+	ld	r7,STK_PARM(r8)(r1)	/* get "local" param */
+_GLOBAL(ht64_call_hpte_updatepp)
+	bl	.			/* patched by htab_finish_init() */
+
+	/* if we failed because typically the HPTE wasn't really here
+	 * we try an insertion.
+	 */
+	cmpdi	0,r3,-1
+	beq-	ht64_insert_pte
+
+	/* Clear the BUSY bit and Write out the PTE */
+	li	r0,_PAGE_BUSY
+	andc	r30,r30,r0
+	b	ht64_write_out_pte
+
+ht64_wrong_access:
+	/* Bail out clearing reservation */
+	stdcx.	r31,0,r6
+	li	r3,1
+	b	ht64_bail
+
+ht64_pte_insert_failure:
+	/* Bail out restoring old PTE */
+	ld	r6,STK_PARM(r6)(r1)
+	std	r31,0(r6)
+	li	r3,-1
+	b	ht64_bail
+
+
+#endif /* CONFIG_PPC_64K_PAGES */
 
 
+/*****************************************************************************
+ *                                                                           *
+ *           Huge pages implementation is in hugetlbpage.c                   *
+ *                                                                           *
+ *****************************************************************************/