EDAC, pnd2: Fix Apollo Lake DIMM detection
Non-existent or empty DIMM slots result in error return from
RD_REGP(). But we shouldn't give up on failure.
So long as we find at least one DIMM we can continue.
Signed-off-by: Tony Luck <tony.luck@intel.com>
Cc: Qiuxu Zhuo <qiuxu.zhuo@intel.com>
Cc: linux-edac <linux-edac@vger.kernel.org>
Link: http://lkml.kernel.org/r/20170628234407.21521-1-tony.luck@intel.com
Signed-off-by: Borislav Petkov <bp@suse.de>
diff --git a/drivers/edac/pnd2_edac.c b/drivers/edac/pnd2_edac.c
index 407f239..8e59949 100644
--- a/drivers/edac/pnd2_edac.c
+++ b/drivers/edac/pnd2_edac.c
@@ -424,16 +424,21 @@
static int apl_get_registers(void)
{
+ int ret = -ENODEV;
int i;
if (RD_REG(&asym_2way, b_cr_asym_2way_mem_region_mchbar))
return -ENODEV;
+ /*
+ * RD_REGP() will fail for unpopulated or non-existent
+ * DIMM slots. Return success if we find at least one DIMM.
+ */
for (i = 0; i < APL_NUM_CHANNELS; i++)
- if (RD_REGP(&drp0[i], d_cr_drp0, apl_dports[i]))
- return -ENODEV;
+ if (!RD_REGP(&drp0[i], d_cr_drp0, apl_dports[i]))
+ ret = 0;
- return 0;
+ return ret;
}
static int dnv_get_registers(void)