Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wirel...

[firefly-linux-kernel-4.4.55.git] / drivers / char / uv_mmtimer.c

diff --git a/drivers/char/uv_mmtimer.c b/drivers/char/uv_mmtimer.c
index 867b67be9f0ac0db007cb8116d7f7b970ab1ba87..c7072ba14f48130d8f04977232bb38ed8dbe067e 100644 (file)
--- a/drivers/char/uv_mmtimer.c
+++ b/drivers/char/uv_mmtimer.c
@@ -89,13 +89,17 @@ static long uv_mmtimer_ioctl(struct file *file, unsigned int cmd,
        switch (cmd) {
        case MMTIMER_GETOFFSET: /* offset of the counter */
                /*
-                * UV RTC register is on its own page
+                * Starting with HUB rev 2.0, the UV RTC register is
+                * replicated across all cachelines of it's own page.
+                * This allows faster simultaneous reads from a given socket.
+                *
+                * The offset returned is in 64 bit units.
                 */
-               if (PAGE_SIZE <= (1 << 16))
-                       ret = ((UV_LOCAL_MMR_BASE | UVH_RTC) & (PAGE_SIZE-1))
-                               / 8;
+               if (uv_get_min_hub_revision_id() == 1)
+                       ret = 0;
                else
-                       ret = -ENOSYS;
+                       ret = ((uv_blade_processor_id() * L1_CACHE_BYTES) %
+                                       PAGE_SIZE) / 8;
                break;
 
        case MMTIMER_GETRES: /* resolution of the clock in 10^-15 s */
@@ -115,8 +119,8 @@ static long uv_mmtimer_ioctl(struct file *file, unsigned int cmd,
                ret = hweight64(UVH_RTC_REAL_TIME_CLOCK_MASK);
                break;
 
-       case MMTIMER_MMAPAVAIL: /* can we mmap the clock into userspace? */
-               ret = (PAGE_SIZE <= (1 << 16)) ? 1 : 0;
+       case MMTIMER_MMAPAVAIL:
+               ret = 1;
                break;
 
        case MMTIMER_GETCOUNTER: