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.
Signed-off-by: Christophe Lombard <clomb...@linux.vnet.ibm.com> --- This patch applies on top of this patch: http://patchwork.ozlabs.org/patch/873663/ Changelog[v4] - Rebased to latest upstream. - Added log message. Changelog[v3] - Rebased to latest upstream. - Dynamic update is now applied to P8. Changelog[v2] - Missing Signed-off-by. - Spaces required around the ':'. --- drivers/misc/cxl/pci.c | 17 ----------------- drivers/misc/cxl/sysfs.c | 11 +++++++++++ 2 files changed, 11 insertions(+), 17 deletions(-) diff --git a/drivers/misc/cxl/pci.c b/drivers/misc/cxl/pci.c index 66eed6a..3247eaf 100644 --- a/drivers/misc/cxl/pci.c +++ b/drivers/misc/cxl/pci.c @@ -606,9 +606,6 @@ static u64 timebase_read_xsl(struct cxl *adapter) static void cxl_setup_psl_timebase(struct cxl *adapter, struct pci_dev *dev) { - u64 psl_tb; - int delta; - unsigned int retry = 0; struct device_node *np; adapter->psl_timebase_synced = false; @@ -636,20 +633,6 @@ static void cxl_setup_psl_timebase(struct cxl *adapter, struct pci_dev *dev) cxl_p1_write(adapter, CXL_PSL_Control, 0x0000000000000000); cxl_p1_write(adapter, CXL_PSL_Control, CXL_PSL_Control_tb); - /* Wait until CORE TB and PSL TB difference <= 16usecs */ - do { - msleep(1); - if (retry++ > 5) { - dev_info(&dev->dev, "PSL timebase can't synchronize\n"); - return; - } - psl_tb = adapter->native->sl_ops->timebase_read(adapter); - delta = mftb() - psl_tb; - if (delta < 0) - delta = -delta; - } while (tb_to_ns(delta) > 16000); - - adapter->psl_timebase_synced = true; return; } diff --git a/drivers/misc/cxl/sysfs.c b/drivers/misc/cxl/sysfs.c index a8b6d6a..a816b93 100644 --- a/drivers/misc/cxl/sysfs.c +++ b/drivers/misc/cxl/sysfs.c @@ -62,6 +62,17 @@ static ssize_t psl_timebase_synced_show(struct device *device, char *buf) { struct cxl *adapter = to_cxl_adapter(device); + u64 psl_tb; + int delta; + + 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); } -- 2.7.4
