x86/platform/uv: Update UV5 TSC checking

Update check of BIOS TSC sync status to include both possible "invalid"
states provided by newer UV5 BIOS.

Signed-off-by: Mike Travis <mike.travis@hpe.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Steve Wahl <steve.wahl@hpe.com>
Link: https://lkml.kernel.org/r/20201005203929.148656-12-mike.travis@hpe.com

diff --git a/arch/x86/include/asm/uv/uv_hub.h b/arch/x86/include/asm/uv/uv_hub.h
index ecf5c93..07079b5 100644 (file)
--- a/arch/x86/include/asm/uv/uv_hub.h
+++ b/arch/x86/include/asm/uv/uv_hub.h
@@ -726,7 +726,7 @@ extern void uv_nmi_setup_hubless(void);
 #define UVH_TSC_SYNC_SHIFT_UV2K        16      /* UV2/3k have different bits */
 #define UVH_TSC_SYNC_MASK      3       /* 0011 */
 #define UVH_TSC_SYNC_VALID     3       /* 0011 */
-#define UVH_TSC_SYNC_INVALID   2       /* 0010 */
+#define UVH_TSC_SYNC_UNKNOWN   0       /* 0000 */
 
 /* BMC sets a bit this MMR non-zero before sending an NMI */
 #define UVH_NMI_MMR            UVH_BIOS_KERNEL_MMR

diff --git a/arch/x86/kernel/apic/x2apic_uv_x.c b/arch/x86/kernel/apic/x2apic_uv_x.c
index 9b44f45..9a83aa1 100644 (file)
--- a/arch/x86/kernel/apic/x2apic_uv_x.c
+++ b/arch/x86/kernel/apic/x2apic_uv_x.c
@@ -197,36 +197,32 @@ static void __init uv_tsc_check_sync(void)
        int sync_state;
        int mmr_shift;
        char *state;
-       bool valid;
 
-       /* Accommodate different UV arch BIOSes */
+       /* Different returns from different UV BIOS versions */
        mmr = uv_early_read_mmr(UVH_TSC_SYNC_MMR);
        mmr_shift =
                is_uv2_hub() ? UVH_TSC_SYNC_SHIFT_UV2K : UVH_TSC_SYNC_SHIFT;
        sync_state = (mmr >> mmr_shift) & UVH_TSC_SYNC_MASK;
 
+       /* Check if TSC is valid for all sockets */
        switch (sync_state) {
        case UVH_TSC_SYNC_VALID:
                state = "in sync";
-               valid = true;
+               mark_tsc_async_resets("UV BIOS");
                break;
 
-       case UVH_TSC_SYNC_INVALID:
-               state = "unstable";
-               valid = false;
+       /* If BIOS state unknown, don't do anything */
+       case UVH_TSC_SYNC_UNKNOWN:
+               state = "unknown";
                break;
+
+       /* Otherwise, BIOS indicates problem with TSC */
        default:
-               state = "unknown: assuming valid";
-               valid = true;
+               state = "unstable";
+               mark_tsc_unstable("UV BIOS");
                break;
        }
        pr_info("UV: TSC sync state from BIOS:0%d(%s)\n", sync_state, state);
-
-       /* Mark flag that says TSC != 0 is valid for socket 0 */
-       if (valid)
-               mark_tsc_async_resets("UV BIOS");
-       else
-               mark_tsc_unstable("UV BIOS");
 }
 
 /* Selector for (4|4A|5) structs */