KVM/MIPS32: KVM Guest kernel support.

Both Guest kernel and Guest Userspace execute in UM. The memory map is as follows:
Guest User address space:   0x00000000 -> 0x40000000
Guest Kernel Unmapped:      0x40000000 -> 0x60000000
Guest Kernel Mapped:        0x60000000 -> 0x80000000
- Guest Usermode virtual memory is limited to 1GB.

Signed-off-by: Sanjay Lal <sanjayl@kymasys.com>
Cc: kvm@vger.kernel.org
Cc: linux-mips@linux-mips.org
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

1 files changed, 15 insertions, 0 deletions

diff --git a/arch/mips/mti-malta/malta-time.c b/arch/mips/mti-malta/malta-time.c
index a144b89cf9ba..bc6ac00c0d57 100644
--- a/arch/mips/mti-malta/malta-time.c
+++ b/arch/mips/mti-malta/malta-time.c
@@ -76,6 +76,21 @@ static void __init estimate_frequencies(void)
         unsigned int count, start;
         unsigned int giccount = 0, gicstart = 0;
 
+#if defined (CONFIG_KVM_GUEST) && defined (CONFIG_KVM_HOST_FREQ)
+        unsigned int prid = read_c0_prid() & 0xffff00;
+
+        /*
+         * XXXKYMA: hardwire the CPU frequency to Host Freq/4
+         */
+        count = (CONFIG_KVM_HOST_FREQ * 1000000) >> 3;
+        if ((prid != (PRID_COMP_MIPS | PRID_IMP_20KC)) &&
+            (prid != (PRID_COMP_MIPS | PRID_IMP_25KF)))
+                count *= 2;
+
+        mips_hpt_frequency = count;
+        return;
+#endif
+
         local_irq_save(flags);
 
         /* Start counter exactly on falling edge of update flag. */