9 files changed, 71 insertions, 57 deletions

diff --git a/arch/powerpc/kernel/Makefile b/arch/powerpc/kernel/Makefile
index 9177b21b1a95..d14cebf62bb0 100644
--- a/arch/powerpc/kernel/Makefile
+++ b/arch/powerpc/kernel/Makefile
@@ -73,7 +73,6 @@ pci64-$(CONFIG_PPC64)		+= pci_dn.o isa-bridge.o
 obj-$(CONFIG_PCI)               += pci_$(CONFIG_WORD_SIZE).o $(pci64-y) \
                                    pci-common.o
 obj-$(CONFIG_PCI_MSI)           += msi.o
-obj-$(CONFIG_RAPIDIO)           += rio.o
 obj-$(CONFIG_KEXEC)             += machine_kexec.o crash.o \
                                    machine_kexec_$(CONFIG_WORD_SIZE).o
 obj-$(CONFIG_AUDIT)             += audit.o
diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c
index 59044e7ed6f4..ec9228d687b0 100644
--- a/arch/powerpc/kernel/asm-offsets.c
+++ b/arch/powerpc/kernel/asm-offsets.c
@@ -63,6 +63,7 @@ int main(void)
 #endif /* CONFIG_PPC64 */
 
         DEFINE(KSP, offsetof(struct thread_struct, ksp));
+        DEFINE(KSP_LIMIT, offsetof(struct thread_struct, ksp_limit));
         DEFINE(PT_REGS, offsetof(struct thread_struct, regs));
         DEFINE(THREAD_FPEXC_MODE, offsetof(struct thread_struct, fpexc_mode));
         DEFINE(THREAD_FPR0, offsetof(struct thread_struct, fpr[0]));
diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S
index 84c868633068..0c8614d9875c 100644
--- a/arch/powerpc/kernel/entry_32.S
+++ b/arch/powerpc/kernel/entry_32.S
@@ -137,11 +137,12 @@ transfer_to_handler:
 2:      /* if from kernel, check interrupted DOZE/NAP mode and
          * check for stack overflow
          */
-        lwz     r9,THREAD_INFO-THREAD(r12)
-        cmplw   r1,r9                   /* if r1 <= current->thread_info */
+        lwz     r9,KSP_LIMIT(r12)
+        cmplw   r1,r9                   /* if r1 <= ksp_limit */
         ble-    stack_ovf               /* then the kernel stack overflowed */
 5:
 #ifdef CONFIG_6xx
+        rlwinm  r9,r1,0,0,31-THREAD_SHIFT
         tophys(r9,r9)                   /* check local flags */
         lwz     r12,TI_LOCAL_FLAGS(r9)
         mtcrf   0x01,r12
diff --git a/arch/powerpc/kernel/head_64.S b/arch/powerpc/kernel/head_64.S
index 215973a2c8d5..024805e1747d 100644
--- a/arch/powerpc/kernel/head_64.S
+++ b/arch/powerpc/kernel/head_64.S
@@ -239,6 +239,10 @@ instruction_access_slb_pSeries:
         .globl  system_call_pSeries
 system_call_pSeries:
         HMT_MEDIUM
+BEGIN_FTR_SECTION
+        cmpdi   r0,0x1ebe
+        beq-    1f
+END_FTR_SECTION_IFSET(CPU_FTR_REAL_LE)
         mr      r9,r13
         mfmsr   r10
         mfspr   r13,SPRN_SPRG3
@@ -253,6 +257,13 @@ system_call_pSeries:
         rfid
         b       .       /* prevent speculative execution */
 
+/* Fast LE/BE switch system call */
+1:      mfspr   r12,SPRN_SRR1
+        xori    r12,r12,MSR_LE
+        mtspr   SPRN_SRR1,r12
+        rfid            /* return to userspace */
+        b       .
+
         STD_EXCEPTION_PSERIES(0xd00, single_step)
         STD_EXCEPTION_PSERIES(0xe00, trap_0e)
 
diff --git a/arch/powerpc/kernel/irq.c b/arch/powerpc/kernel/irq.c
index 425616f92d18..2f73f705d564 100644
--- a/arch/powerpc/kernel/irq.c
+++ b/arch/powerpc/kernel/irq.c
@@ -307,6 +307,7 @@ void do_IRQ(struct pt_regs *regs)
                 if (curtp != irqtp) {
                         struct irq_desc *desc = irq_desc + irq;
                         void *handler = desc->handle_irq;
+                        unsigned long saved_sp_limit = current->thread.ksp_limit;
                         if (handler == NULL)
                                 handler = &__do_IRQ;
                         irqtp->task = curtp->task;
@@ -319,7 +320,10 @@ void do_IRQ(struct pt_regs *regs)
                                 (irqtp->preempt_count & ~SOFTIRQ_MASK) |
                                 (curtp->preempt_count & SOFTIRQ_MASK);
 
+                        current->thread.ksp_limit = (unsigned long)irqtp +
+                                _ALIGN_UP(sizeof(struct thread_info), 16);
                         call_handle_irq(irq, desc, irqtp, handler);
+                        current->thread.ksp_limit = saved_sp_limit;
                         irqtp->task = NULL;
 
 
@@ -352,9 +356,7 @@ void __init init_IRQ(void)
 {
         if (ppc_md.init_IRQ)
                 ppc_md.init_IRQ();
-#ifdef CONFIG_PPC64
         irq_ctx_init();
-#endif
 }
 
 
@@ -383,11 +385,15 @@ void irq_ctx_init(void)
 static inline void do_softirq_onstack(void)
 {
         struct thread_info *curtp, *irqtp;
+        unsigned long saved_sp_limit = current->thread.ksp_limit;
 
         curtp = current_thread_info();
         irqtp = softirq_ctx[smp_processor_id()];
         irqtp->task = curtp->task;
+        current->thread.ksp_limit = (unsigned long)irqtp +
+                                    _ALIGN_UP(sizeof(struct thread_info), 16);
         call_do_softirq(irqtp);
+        current->thread.ksp_limit = saved_sp_limit;
         irqtp->task = NULL;
 }
 
diff --git a/arch/powerpc/kernel/misc_32.S b/arch/powerpc/kernel/misc_32.S
index 92ccc6fcc5b0..89aaaa6f3561 100644
--- a/arch/powerpc/kernel/misc_32.S
+++ b/arch/powerpc/kernel/misc_32.S
@@ -32,6 +32,31 @@
 
         .text
 
+#ifdef CONFIG_IRQSTACKS
+_GLOBAL(call_do_softirq)
+        mflr    r0
+        stw     r0,4(r1)
+        stwu    r1,THREAD_SIZE-STACK_FRAME_OVERHEAD(r3)
+        mr      r1,r3
+        bl      __do_softirq
+        lwz     r1,0(r1)
+        lwz     r0,4(r1)
+        mtlr    r0
+        blr
+
+_GLOBAL(call_handle_irq)
+        mflr    r0
+        stw     r0,4(r1)
+        mtctr   r6
+        stwu    r1,THREAD_SIZE-STACK_FRAME_OVERHEAD(r5)
+        mr      r1,r5
+        bctrl
+        lwz     r1,0(r1)
+        lwz     r0,4(r1)
+        mtlr    r0
+        blr
+#endif /* CONFIG_IRQSTACKS */
+
 /*
  * This returns the high 64 bits of the product of two 64-bit numbers.
  */
diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
index 6caad17ea72e..7de41c3948ec 100644
--- a/arch/powerpc/kernel/process.c
+++ b/arch/powerpc/kernel/process.c
@@ -589,6 +589,8 @@ int copy_thread(int nr, unsigned long clone_flags, unsigned long usp,
         kregs = (struct pt_regs *) sp;
         sp -= STACK_FRAME_OVERHEAD;
         p->thread.ksp = sp;
+        p->thread.ksp_limit = (unsigned long)task_stack_page(p) +
+                                _ALIGN_UP(sizeof(struct thread_info), 16);
 
 #ifdef CONFIG_PPC64
         if (cpu_has_feature(CPU_FTR_SLB)) {
diff --git a/arch/powerpc/kernel/rio.c b/arch/powerpc/kernel/rio.c
deleted file mode 100644
index 29487fedfc76..000000000000
--- a/arch/powerpc/kernel/rio.c
+++ /dev/null
@@ -1,52 +0,0 @@
-/*
- * RapidIO PPC32 support
- *
- * Copyright 2005 MontaVista Software, Inc.
- * Matt Porter <mporter@kernel.crashing.org>
- *
- * This program is free software; you can redistribute  it and/or modify it
- * under  the terms of  the GNU General  Public License as published by the
- * Free Software Foundation;  either version 2 of the  License, or (at your
- * option) any later version.
- */
-
-#include <linux/init.h>
-#include <linux/kernel.h>
-#include <linux/rio.h>
-
-#include <asm/rio.h>
-
-/**
- * platform_rio_init - Do platform specific RIO init
- *
- * Any platform specific initialization of RapdIO
- * hardware is done here as well as registration
- * of any active master ports in the system.
- */
-void __attribute__ ((weak))
-    platform_rio_init(void)
-{
-        printk(KERN_WARNING "RIO: No platform_rio_init() present\n");
-}
-
-/**
- * ppc_rio_init - Do PPC32 RIO init
- *
- * Calls platform-specific RIO init code and then calls
- * rio_init_mports() to initialize any master ports that
- * have been registered with the RIO subsystem.
- */
-static int __init ppc_rio_init(void)
-{
-        printk(KERN_INFO "RIO: RapidIO init\n");
-
-        /* Platform specific initialization */
-        platform_rio_init();
-
-        /* Enumerate all registered ports */
-        rio_init_mports();
-
-        return 0;
-}
-
-subsys_initcall(ppc_rio_init);
diff --git a/arch/powerpc/kernel/setup_32.c b/arch/powerpc/kernel/setup_32.c
index 36f6779c88d4..5112a4aa801d 100644
--- a/arch/powerpc/kernel/setup_32.c
+++ b/arch/powerpc/kernel/setup_32.c
@@ -16,6 +16,7 @@
 #include <linux/root_dev.h>
 #include <linux/cpu.h>
 #include <linux/console.h>
+#include <linux/lmb.h>
 
 #include <asm/io.h>
 #include <asm/prom.h>
@@ -229,6 +230,24 @@ int __init ppc_init(void)
 
 arch_initcall(ppc_init);
 
+#ifdef CONFIG_IRQSTACKS
+static void __init irqstack_early_init(void)
+{
+        unsigned int i;
+
+        /* interrupt stacks must be in lowmem, we get that for free on ppc32
+         * as the lmb is limited to lowmem by LMB_REAL_LIMIT */
+        for_each_possible_cpu(i) {
+                softirq_ctx[i] = (struct thread_info *)
+                        __va(lmb_alloc(THREAD_SIZE, THREAD_SIZE));
+                hardirq_ctx[i] = (struct thread_info *)
+                        __va(lmb_alloc(THREAD_SIZE, THREAD_SIZE));
+        }
+}
+#else
+#define irqstack_early_init()
+#endif
+
 /* Warning, IO base is not yet inited */
 void __init setup_arch(char **cmdline_p)
 {
@@ -286,6 +305,8 @@ void __init setup_arch(char **cmdline_p)
         init_mm.end_data = (unsigned long) _edata;
         init_mm.brk = klimit;
 
+        irqstack_early_init();
+
         /* set up the bootmem stuff with available memory */
         do_init_bootmem();
         if ( ppc_md.progress ) ppc_md.progress("setup_arch: bootmem", 0x3eab);