[PATCH] Remove NACA fixed address constraint

Comments in head.S suggest that the iSeries naca has a fixed address,
because tools expect to find it there.  The only tool which appears to
access the naca is addRamDisk, but both the in-kernel version and the
version used in RHEL and SuSE in fact locate the NACA the same way as
the hypervisor does, by following the pointer in the hvReleaseData
structure.

Since the requirement for a fixed address seems to be obsolete, this
patch removes the naca from head.S and replaces it with a normal C
initializer.

For good measure, it removes an old version of addRamDisk.c which was
sitting, unused, in the ppc32 tree.

Signed-off-by: David Gibson <dwg@au1.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>

arch/ppc64/kernel/LparData.c

@@ -51,6 +51,17 @@ struct HvReleaseData hvReleaseData = {
 		0xf4, 0x4b, 0xf6, 0xf4 },
 };
 
+/*
+ * The NACA.  The first dword of the naca is required by the iSeries
+ * hypervisor to point to itVpdAreas.  The hypervisor finds the NACA
+ * through the pointer in hvReleaseData.
+ */
+struct naca_struct naca = {
+	.xItVpdAreas = &itVpdAreas,
+	.xRamDisk = 0,
+	.xRamDiskSize = 0,
+};
+
 extern void system_reset_iSeries(void);
 extern void machine_check_iSeries(void);
 extern void data_access_iSeries(void);

arch/ppc64/kernel/head.S

@@ -30,7 +30,6 @@
 #include <asm/processor.h>
 #include <asm/page.h>
 #include <asm/mmu.h>
-#include <asm/naca.h>
 #include <asm/systemcfg.h>
 #include <asm/ppc_asm.h>
 #include <asm/offsets.h>
@@ -511,24 +510,10 @@ _GLOBAL(do_stab_bolted_pSeries)
 	mfspr	r12,SPRG2
 	EXCEPTION_PROLOG_PSERIES(PACA_EXSLB, .do_stab_bolted)
 
-
-	/* Space for the naca.  Architected to be located at real address
-	 * NACA_PHYS_ADDR.  Various tools rely on this location being fixed.
-	 * The first dword of the naca is required by iSeries LPAR to
-	 * point to itVpdAreas.  On pSeries native, this value is not used.
-	 */
-	. = NACA_PHYS_ADDR
-	.globl __end_interrupts
-__end_interrupts:
-#ifdef CONFIG_PPC_ISERIES
-	.globl naca
-naca:
-	.llong	itVpdAreas
-	.llong	0		/* xRamDisk */
-	.llong	0		/* xRamDiskSize */
 
 	. = 0x6100
 
+#ifdef CONFIG_PPC_ISERIES
 /***  ISeries-LPAR interrupt handlers ***/
 
 	STD_EXCEPTION_ISERIES(0x200, machine_check, PACA_EXMC)

include/asm-ppc64/naca.h

@@ -12,8 +12,6 @@
 
 #include <asm/types.h>
 
-#ifndef __ASSEMBLY__
-
 struct naca_struct {
 	/* Kernel only data - undefined for user space */
 	void *xItVpdAreas;              /* VPD Data                  0x00 */
@@ -23,9 +21,4 @@ struct naca_struct {
 
 extern struct naca_struct naca;
 
-#endif /* __ASSEMBLY__ */
-
-#define NACA_PAGE      0x4
-#define NACA_PHYS_ADDR (NACA_PAGE<<PAGE_SHIFT)
-
 #endif /* _NACA_H */