[SPARC64]: Detect sun4v early in boot process.

We look for "SUNW,sun4v" in the 'compatible' property
of the root OBP device tree node.

Protect every %ver register access, to make sure it is
not touched on sun4v, as %ver is hyperprivileged there.

Lock kernel TLB entries using hypervisor calls instead of
calls into OBP.

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 3 insertions, 0 deletions

diff --git a/arch/sparc64/kernel/us3_cpufreq.c b/arch/sparc64/kernel/us3_cpufreq.c
index 6d1f9a3c464f..a912c45bdc05 100644
--- a/arch/sparc64/kernel/us3_cpufreq.c
+++ b/arch/sparc64/kernel/us3_cpufreq.c
@@ -203,6 +203,9 @@ static int __init us3_freq_init(void)
         unsigned long manuf, impl, ver;
         int ret;
 
+        if (tlb_type != cheetah && tlb_type != cheetah_plus)
+                return -ENODEV;
+
         __asm__("rdpr %%ver, %0" : "=r" (ver));
         manuf = ((ver >> 48) & 0xffff);
         impl  = ((ver >> 32) & 0xffff);