cxl: Allow initialization on timebase sync failures
Failure to synchronize the PSL timebase currently prevents the
initialization of the cxl card, thus rendering the card useless. This
is too extreme for a feature which is rarely used, if at all. No
hardware AFUs or software is currently using PSL timebase.
This patch still tries to synchronize the PSL timebase when the card
is initialized, but ignores the error if it can't. Instead, it reports
a status via /sys.
Signed-off-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Acked-by: Ian Munsie <imunsie@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
diff --git a/drivers/misc/cxl/pci.c b/drivers/misc/cxl/pci.c
index 94fd3f7..c6d5cf5 100644
--- a/drivers/misc/cxl/pci.c
+++ b/drivers/misc/cxl/pci.c
@@ -394,22 +394,24 @@
#define TBSYNC_CNT(n) (((u64)n & 0x7) << (63-6))
#define _2048_250MHZ_CYCLES 1
-static int cxl_setup_psl_timebase(struct cxl *adapter, struct pci_dev *dev)
+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;
+
if (!(np = pnv_pci_get_phb_node(dev)))
- return -ENODEV;
+ return;
/* Do not fail when CAPP timebase sync is not supported by OPAL */
of_node_get(np);
if (! of_get_property(np, "ibm,capp-timebase-sync", NULL)) {
of_node_put(np);
- pr_err("PSL: Timebase sync: OPAL support missing\n");
- return 0;
+ dev_info(&dev->dev, "PSL timebase inactive: OPAL support missing\n");
+ return;
}
of_node_put(np);
@@ -428,8 +430,8 @@
do {
msleep(1);
if (retry++ > 5) {
- pr_err("PSL: Timebase sync: giving up!\n");
- return -EIO;
+ dev_info(&dev->dev, "PSL timebase can't synchronize\n");
+ return;
}
psl_tb = cxl_p1_read(adapter, CXL_PSL_Timebase);
delta = mftb() - psl_tb;
@@ -437,7 +439,8 @@
delta = -delta;
} while (tb_to_ns(delta) > 16000);
- return 0;
+ adapter->psl_timebase_synced = true;
+ return;
}
static int init_implementation_afu_regs(struct cxl_afu *afu)
@@ -1183,8 +1186,8 @@
if ((rc = pnv_phb_to_cxl_mode(dev, OPAL_PHB_CAPI_MODE_SNOOP_ON)))
goto err;
- if ((rc = cxl_setup_psl_timebase(adapter, dev)))
- goto err;
+ /* Ignore error, adapter init is not dependant on timebase sync */
+ cxl_setup_psl_timebase(adapter, dev);
if ((rc = cxl_native_register_psl_err_irq(adapter)))
goto err;