Merge branch 'devel' of master.kernel.org:/home/rmk/linux-2.6-arm

* 'devel' of master.kernel.org:/home/rmk/linux-2.6-arm: (416 commits)
  ARM: DMA: add support for DMA debugging
  ARM: PL011: add DMA burst threshold support for ST variants
  ARM: PL011: Add support for transmit DMA
  ARM: PL011: Ensure IRQs are disabled in UART interrupt handler
  ARM: PL011: Separate hardware FIFO size from TTY FIFO size
  ARM: PL011: Allow better handling of vendor data
  ARM: PL011: Ensure error flags are clear at startup
  ARM: PL011: include revision number in boot-time port printk
  ARM: vexpress: add sched_clock() for Versatile Express
  ARM i.MX53: Make MX53 EVK bootable
  ARM i.MX53: Some bug fix about MX53 MSL code
  ARM: 6607/1: sa1100: Update platform device registration
  ARM: 6606/1: sa1100: Fix platform device registration
  ARM i.MX51: rename IPU irqs
  ARM i.MX51: Add ipu clock support
  ARM: imx/mx27_3ds: Add PMIC support
  ARM: DMA: Replace page_to_dma()/dma_to_page() with pfn_to_dma()/dma_to_pfn()
  mx51: fix usb clock support
  MX51: Add support for usb host 2
  arch/arm/plat-mxc/ehci.c: fix errors/typos
  ...

1 files changed, 23 insertions, 1 deletions

diff --git a/arch/arm/vfp/vfpmodule.c b/arch/arm/vfp/vfpmodule.c
index 8063a322c790..0797cb528b46 100644
--- a/arch/arm/vfp/vfpmodule.c
+++ b/arch/arm/vfp/vfpmodule.c
@@ -10,9 +10,12 @@
  */
 #include <linux/module.h>
 #include <linux/types.h>
+#include <linux/cpu.h>
 #include <linux/kernel.h>
+#include <linux/notifier.h>
 #include <linux/signal.h>
 #include <linux/sched.h>
+#include <linux/smp.h>
 #include <linux/init.h>
 
 #include <asm/cputype.h>
@@ -484,7 +487,24 @@ void vfp_flush_hwstate(struct thread_info *thread)
 	put_cpu();
 }
 
-#include <linux/smp.h>
+/*
+ * VFP hardware can lose all context when a CPU goes offline.
+ * Safely clear our held state when a CPU has been killed, and
+ * re-enable access to VFP when the CPU comes back online.
+ *
+ * Both CPU_DYING and CPU_STARTING are called on the CPU which
+ * is being offlined/onlined.
+ */
+static int vfp_hotplug(struct notifier_block *b, unsigned long action,
+	void *hcpu)
+{
+	if (action == CPU_DYING || action == CPU_DYING_FROZEN) {
+		unsigned int cpu = (long)hcpu;
+		last_VFP_context[cpu] = NULL;
+	} else if (action == CPU_STARTING || action == CPU_STARTING_FROZEN)
+		vfp_enable(NULL);
+	return NOTIFY_OK;
+}
 
 /*
  * VFP support code initialisation.
@@ -514,6 +534,8 @@ static int __init vfp_init(void)
 	else if (vfpsid & FPSID_NODOUBLE) {
 		printk("no double precision support\n");
 	} else {
+		hotcpu_notifier(vfp_hotplug, 0);
+
 		smp_call_function(vfp_enable, NULL, 1);
 
 		VFP_arch = (vfpsid & FPSID_ARCH_MASK) >> FPSID_ARCH_BIT;  /* Extract the architecture version */