[PATCH] ppc64: SLB accounting fix

From: Anton Blanchard <anton@samba.org>

Even though we have a variable containing the number of entries in the SLB,
we hardwire the value at boot.  We also dont use the variable in the head.S
fastpath handler.

This patch removes it.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

arch/ppc64/kernel/asm-offsets.c

@@ -73,7 +73,6 @@ int main(void)
         DEFINE(ICACHEL1LINESIZE, offsetof(struct systemcfg, iCacheL1LineSize));
         DEFINE(ICACHEL1LOGLINESIZE, offsetof(struct naca_struct, iCacheL1LogLineSize));
         DEFINE(ICACHEL1LINESPERPAGE, offsetof(struct naca_struct, iCacheL1LinesPerPage));
-	DEFINE(SLBSIZE, offsetof(struct naca_struct, slb_size));
 	DEFINE(PLATFORM, offsetof(struct systemcfg, platform));
 
 	/* paca */

arch/ppc64/kernel/head.S

@@ -1123,8 +1123,6 @@ _GLOBAL(do_slb_bolted)
 	 */
 
 	/* r20 = paca */
-	/* use a cpu feature mask if we ever change our slb size */
-SLB_NUM_ENTRIES = 64
 1:	ld	r22,PACASTABRR(r20)
 	addi	r21,r22,1
 	cmpdi	r21,SLB_NUM_ENTRIES

arch/ppc64/kernel/iSeries_setup.c

@@ -563,11 +563,6 @@ static void __init build_iSeries_Memory_Map(void)
 	lmb_add(0, systemcfg->physicalMemorySize);
 	lmb_analyze();	/* ?? */
 	lmb_reserve(0, __pa(klimit));
-
-	/* 
-	 * Hardcode to GP size.  I am not sure where to get this info. DRENG
-	 */
-	naca->slb_size = 64;
 }
 
 /*

arch/ppc64/kernel/prom.c

@@ -458,13 +458,6 @@ static void __init prom_initialize_naca(void)
 		PROM_BUG();
 	}
 
-	/* 
-	 * Hardcode to GP size.  I am not sure where to get this info
-	 * in general, as there does not appear to be a slb-size OF
-	 * entry.  At least in Condor and earlier.  DRENG 
-	 */
-	_naca->slb_size = 64;
-
 	/* Add an eye catcher and the systemcfg layout version number */
 	strcpy(_systemcfg->eye_catcher, RELOC("SYSTEMCFG:PPC64"));
 	_systemcfg->version.major = SYSTEMCFG_MAJOR;

arch/ppc64/kernel/stab.c

@@ -356,7 +356,7 @@ static void make_slbe(unsigned long esid, unsigned long vsid, int large,
 		 * We bolt in the first kernel segment and the first
 		 * vmalloc segment.
 		 */
-		if (castout_entry >= naca->slb_size)
+		if (castout_entry >= SLB_NUM_ENTRIES)
 			castout_entry = 2;
 		asm volatile("slbmfee  %0,%1" : "=r" (esid_data) : "r" (entry));
 	} while (esid_data.data.v &&

arch/ppc64/xmon/xmon.c

@@ -2512,7 +2512,7 @@ static void dump_slb(void)
 
 	printf("SLB contents of cpu %x\n", smp_processor_id());
 
-	for (i = 0; i < naca->slb_size; i++) {
+	for (i = 0; i < SLB_NUM_ENTRIES; i++) {
 		asm volatile("slbmfee  %0,%1" : "=r" (tmp) : "r" (i));
 		printf("%02d %016lx ", i, tmp);
 

include/asm-ppc64/naca.h

@@ -30,7 +30,7 @@ struct naca_struct {
 	u64 log;                        /* Ptr to log buffer         0x30 */
 	u64 serialPortAddr;		/* Phy addr of serial port   0x38 */
 	u64 interrupt_controller;	/* Type of int controller    0x40 */ 
-	u64 slb_size;			/* SLB size in entries       0x48 */
+	u64 unused1;			/* was SLB size in entries   0x48 */
 	u64 pftSize;			/* Log 2 of page table size  0x50 */
 	void *systemcfg;		/* Pointer to systemcfg data 0x58 */
 	u32 dCacheL1LogLineSize;	/* L1 d-cache line size Log2 0x60 */

include/asm-ppc64/processor.h

@@ -634,4 +634,10 @@ static inline void prefetchw(const void *x)
 
 #endif /* ASSEMBLY */
 
+/*
+ * Number of entries in the SLB. If this ever changes we should handle
+ * it with a use a cpu feature fixup.
+ */
+#define SLB_NUM_ENTRIES 64
+
 #endif /* __ASM_PPC64_PROCESSOR_H */