4 files changed, 139 insertions, 15 deletions

diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index d56d21c0573b..e2c79a24d3c6 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -999,8 +999,8 @@ source arch/arm/mm/Kconfig
 
 config IWMMXT
         bool "Enable iWMMXt support"
-        depends on CPU_XSCALE || CPU_XSC3 || CPU_MOHAWK
-        default y if PXA27x || PXA3xx || ARCH_MMP
+        depends on CPU_XSCALE || CPU_XSC3 || CPU_MOHAWK || CPU_PJ4
+        default y if PXA27x || PXA3xx || PXA95x || ARCH_MMP
         help
           Enable support for iWMMXt context switching at run time if
           running on a CPU that supports it.
diff --git a/arch/arm/kernel/Makefile b/arch/arm/kernel/Makefile
index 5b9b268f4fbb..b0f11fa7a4b4 100644
--- a/arch/arm/kernel/Makefile
+++ b/arch/arm/kernel/Makefile
@@ -50,6 +50,7 @@ AFLAGS_crunch-bits.o		:= -Wa,-mcpu=ep9312
 obj-$(CONFIG_CPU_XSCALE)        += xscale-cp0.o
 obj-$(CONFIG_CPU_XSC3)          += xscale-cp0.o
 obj-$(CONFIG_CPU_MOHAWK)        += xscale-cp0.o
+obj-$(CONFIG_CPU_PJ4)           += pj4-cp0.o
 obj-$(CONFIG_IWMMXT)            += iwmmxt.o
 obj-$(CONFIG_CPU_HAS_PMU)       += pmu.o
 obj-$(CONFIG_HW_PERF_EVENTS)    += perf_event.o
diff --git a/arch/arm/kernel/iwmmxt.S b/arch/arm/kernel/iwmmxt.S
index b63b528f22a6..7fa3bb0d2397 100644
--- a/arch/arm/kernel/iwmmxt.S
+++ b/arch/arm/kernel/iwmmxt.S
@@ -19,6 +19,14 @@
 #include <asm/thread_info.h>
 #include <asm/asm-offsets.h>
 
+#if defined(CONFIG_CPU_PJ4)
+#define PJ4(code...)            code
+#define XSC(code...)
+#else
+#define PJ4(code...)
+#define XSC(code...)            code
+#endif
+
 #define MMX_WR0                 (0x00)
 #define MMX_WR1                 (0x08)
 #define MMX_WR2                 (0x10)
@@ -58,11 +66,17 @@
 
 ENTRY(iwmmxt_task_enable)
 
-        mrc     p15, 0, r2, c15, c1, 0
-        tst     r2, #0x3                        @ CP0 and CP1 accessible?
+        XSC(mrc p15, 0, r2, c15, c1, 0)
+        PJ4(mrc p15, 0, r2, c1, c0, 2)
+        @ CP0 and CP1 accessible?
+        XSC(tst r2, #0x3)
+        PJ4(tst r2, #0xf)
         movne   pc, lr                          @ if so no business here
-        orr     r2, r2, #0x3                    @ enable access to CP0 and CP1
-        mcr     p15, 0, r2, c15, c1, 0
+        @ enable access to CP0 and CP1
+        XSC(orr r2, r2, #0x3)
+        XSC(mcr p15, 0, r2, c15, c1, 0)
+        PJ4(orr r2, r2, #0xf)
+        PJ4(mcr p15, 0, r2, c1, c0, 2)
 
         ldr     r3, =concan_owner
         add     r0, r10, #TI_IWMMXT_STATE       @ get task Concan save area
@@ -179,17 +193,26 @@ ENTRY(iwmmxt_task_disable)
         teqne   r1, r2                          @ or specified one?
         bne     1f                              @ no: quit
 
-        mrc     p15, 0, r4, c15, c1, 0
-        orr     r4, r4, #0x3                    @ enable access to CP0 and CP1
-        mcr     p15, 0, r4, c15, c1, 0
+        @ enable access to CP0 and CP1
+        XSC(mrc p15, 0, r4, c15, c1, 0)
+        XSC(orr r4, r4, #0xf)
+        XSC(mcr p15, 0, r4, c15, c1, 0)
+        PJ4(mrc p15, 0, r4, c1, c0, 2)
+        PJ4(orr r4, r4, #0x3)
+        PJ4(mcr p15, 0, r4, c1, c0, 2)
+
         mov     r0, #0                          @ nothing to load
         str     r0, [r3]                        @ no more current owner
         mrc     p15, 0, r2, c2, c0, 0
         mov     r2, r2                          @ cpwait
         bl      concan_save
 
-        bic     r4, r4, #0x3                    @ disable access to CP0 and CP1
-        mcr     p15, 0, r4, c15, c1, 0
+        @ disable access to CP0 and CP1
+        XSC(bic r4, r4, #0x3)
+        XSC(mcr p15, 0, r4, c15, c1, 0)
+        PJ4(bic r4, r4, #0xf)
+        PJ4(mcr p15, 0, r4, c1, c0, 2)
+
         mrc     p15, 0, r2, c2, c0, 0
         mov     r2, r2                          @ cpwait
 
@@ -277,8 +300,11 @@ ENTRY(iwmmxt_task_restore)
  */
 ENTRY(iwmmxt_task_switch)
 
-        mrc     p15, 0, r1, c15, c1, 0
-        tst     r1, #0x3                        @ CP0 and CP1 accessible?
+        XSC(mrc p15, 0, r1, c15, c1, 0)
+        PJ4(mrc p15, 0, r1, c1, c0, 2)
+        @ CP0 and CP1 accessible?
+        XSC(tst r1, #0x3)
+        PJ4(tst r1, #0xf)
         bne     1f                              @ yes: block them for next task
 
         ldr     r2, =concan_owner
@@ -287,8 +313,11 @@ ENTRY(iwmmxt_task_switch)
         teq     r2, r3                          @ next task owns it?
         movne   pc, lr                          @ no: leave Concan disabled
 
-1:      eor     r1, r1, #3                      @ flip Concan access
-        mcr     p15, 0, r1, c15, c1, 0
+1:      @ flip Conan access
+        XSC(eor r1, r1, #0x3)
+        XSC(mcr p15, 0, r1, c15, c1, 0)
+        PJ4(eor r1, r1, #0xf)
+        PJ4(mcr p15, 0, r1, c1, c0, 2)
 
         mrc     p15, 0, r1, c2, c0, 0
         sub     pc, lr, r1, lsr #32             @ cpwait and return
diff --git a/arch/arm/kernel/pj4-cp0.c b/arch/arm/kernel/pj4-cp0.c
new file mode 100644
index 000000000000..a4b1b0748fd3
--- /dev/null
+++ b/arch/arm/kernel/pj4-cp0.c
@@ -0,0 +1,94 @@
+/*
+ * linux/arch/arm/kernel/pj4-cp0.c
+ *
+ * PJ4 iWMMXt coprocessor context switching and handling
+ *
+ * Copyright (c) 2010 Marvell International Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/signal.h>
+#include <linux/sched.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <asm/thread_notify.h>
+
+static int iwmmxt_do(struct notifier_block *self, unsigned long cmd, void *t)
+{
+        struct thread_info *thread = t;
+
+        switch (cmd) {
+        case THREAD_NOTIFY_FLUSH:
+                /*
+                 * flush_thread() zeroes thread->fpstate, so no need
+                 * to do anything here.
+                 *
+                 * FALLTHROUGH: Ensure we don't try to overwrite our newly
+                 * initialised state information on the first fault.
+                 */
+
+        case THREAD_NOTIFY_EXIT:
+                iwmmxt_task_release(thread);
+                break;
+
+        case THREAD_NOTIFY_SWITCH:
+                iwmmxt_task_switch(thread);
+                break;
+        }
+
+        return NOTIFY_DONE;
+}
+
+static struct notifier_block iwmmxt_notifier_block = {
+        .notifier_call  = iwmmxt_do,
+};
+
+
+static u32 __init pj4_cp_access_read(void)
+{
+        u32 value;
+
+        __asm__ __volatile__ (
+                "mrc    p15, 0, %0, c1, c0, 2\n\t"
+                : "=r" (value));
+        return value;
+}
+
+static void __init pj4_cp_access_write(u32 value)
+{
+        u32 temp;
+
+        __asm__ __volatile__ (
+                "mcr    p15, 0, %1, c1, c0, 2\n\t"
+                "mrc    p15, 0, %0, c1, c0, 2\n\t"
+                "mov    %0, %0\n\t"
+                "sub    pc, pc, #4\n\t"
+                : "=r" (temp) : "r" (value));
+}
+
+
+/*
+ * Disable CP0/CP1 on boot, and let call_fpe() and the iWMMXt lazy
+ * switch code handle iWMMXt context switching.
+ */
+static int __init pj4_cp0_init(void)
+{
+        u32 cp_access;
+
+        cp_access = pj4_cp_access_read() & ~0xf;
+        pj4_cp_access_write(cp_access);
+
+        printk(KERN_INFO "PJ4 iWMMXt coprocessor enabled.\n");
+        elf_hwcap |= HWCAP_IWMMXT;
+        thread_register_notifier(&iwmmxt_notifier_block);
+
+        return 0;
+}
+
+late_initcall(pj4_cp0_init);