diff options
| author | Christophe Lombard <clombard@linux.vnet.ibm.com> | 2018-02-20 14:48:56 +0100 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2018-03-14 20:01:18 +1100 |
| commit | c2be663d5307fb9751a562ac664fa78cd7a00e2b (patch) | |
| tree | bda7db5d90520ac164fb3948d49677180201d29c /drivers/misc/cxl/sysfs.c | |
| parent | 014a32b30e9d81b47ef82b9995b52c3a0c8b4082 (diff) | |
cxl: Fix timebase synchronization status on P9
The PSL Timebase register is updated by the PSL to maintain the
timebase.
On P9, the Timebase value is only provided by the CAPP as received the
last time a timebase request was performed.
The timebase requests are initiated through the adapter configuration
or application registers.
The specific sysfs entry "/sys/class/cxl/cardxx/psl_timebase_synced"
is now dynamically updated according the content of the PSL Timebase
register.
Fixes: f24be42aab37 ("cxl: Add psl9 specific code")
Signed-off-by: Christophe Lombard <clombard@linux.vnet.ibm.com>
Reviewed-by: Vaibhav Jain <vaibhav@linux.vnet.ibm.com>
Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diffstat (limited to 'drivers/misc/cxl/sysfs.c')
| -rw-r--r-- | drivers/misc/cxl/sysfs.c | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/drivers/misc/cxl/sysfs.c b/drivers/misc/cxl/sysfs.c index a8b6d6a635e9..95285b7f636f 100644 --- a/drivers/misc/cxl/sysfs.c +++ b/drivers/misc/cxl/sysfs.c @@ -62,7 +62,19 @@ static ssize_t psl_timebase_synced_show(struct device *device, char *buf) { struct cxl *adapter = to_cxl_adapter(device); + u64 psl_tb, delta; + /* Recompute the status only in native mode */ + if (cpu_has_feature(CPU_FTR_HVMODE)) { + psl_tb = adapter->native->sl_ops->timebase_read(adapter); + delta = abs(mftb() - psl_tb); + + /* CORE TB and PSL TB difference <= 16usecs ? */ + adapter->psl_timebase_synced = (tb_to_ns(delta) < 16000) ? true : false; + pr_devel("PSL timebase %s - delta: 0x%016llx\n", + (tb_to_ns(delta) < 16000) ? "synchronized" : + "not synchronized", tb_to_ns(delta)); + } return scnprintf(buf, PAGE_SIZE, "%i\n", adapter->psl_timebase_synced); } |