[PATCH] pciutils lspci: Add reporting of L1 PM Substate capability

["David Box" <david.e.box@linux.intel.com>]

L1 PM Substates is a new PCI power management feature that can enable
lower power consumption when a PCIe Link is idle. This change to the PCI
Base Specification is reflected in the PCI-SIG ECN titled
"L1 PM Substates with CLKREQ".

Signed-off-by: David E. Box <david.e.box@linux.intel.com>
---
 lib/header.h |  1 +
 ls-ecaps.c   | 54 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 55 insertions(+)

diff --git a/lib/header.h b/lib/header.h
index 69518fd..6608003 100644
--- a/lib/header.h
+++ b/lib/header.h
@@ -226,6 +226,7 @@
 #define PCI_EXT_CAP_ID_SRIOV	0x10	/* Single Root I/O Virtualization */
#define PCI_EXT_CAP_ID_TPH	0x17	/* Transaction processing hints */ #define
PCI_EXT_CAP_ID_LTR	0x18	/* Latency Tolerance Reporting */
+#define PCI_EXT_CAP_ID_L1PM	0x1e	/* L1 PM Substates */

 /*** Definitions of capabilities ***/

diff --git a/ls-ecaps.c b/ls-ecaps.c
index 161c275..7b28ce5 100644
--- a/ls-ecaps.c
+++ b/ls-ecaps.c
@@ -448,6 +448,57 @@ cap_evendor(struct device *d, int where)
     BITS(hdr, 20, 12));
 }

+static void
+cap_l1pm(struct device *d, int where)
+{
+  u32 l1_cap;
+  int power_on_scale;
+
+  printf("L1 PM Substates\n");
+
+  if (verbose < 2)
+    return;
+
+  if (!config_fetch(d, where + 4, 4)) {
+      printf("\t\t<unreadable>\n");
+      return;
+  }
+
+  l1_cap = get_conf_long(d, where + 4);
+
+  printf("\t\tL1SubCap: ");
+  printf("PCI-PM_L1.2%c, PCI-PM_L1.1%c, ASPM_L1.2%c, ASPM_L1.1%c," +    "
L1_PM_Substates%c\n",
+    FLAG(l1_cap, 1),
+    FLAG(l1_cap, 2),
+    FLAG(l1_cap, 4),
+    FLAG(l1_cap, 8),
+    FLAG(l1_cap, 16));
+
+  if (BITS(l1_cap, 0, 1) || BITS(l1_cap, 2, 1)) {
+    printf("\t\t\t  PortCommonModeRestoreTime=%dus, ",
+    	BITS(l1_cap, 8,8));
+
+    power_on_scale = BITS(l1_cap, 16, 2);
+
+    printf("PortTPowerOnTime=");
+    switch (power_on_scale) {
+      case 0:
+      	printf("%dus\n", BITS(l1_cap, 19, 5) * 2);
+      	break;
+      case 1:
+      	printf("%dus\n", BITS(l1_cap, 19, 5) * 10);
+      	break;
+      case 2:
+      	printf("%dus\n", BITS(l1_cap, 19, 5) * 100);
+      	break;
+      default:
+      	printf("<error>\n");
+      	break;
+    }
+  }
+}
+
 void
 show_ext_caps(struct device *d)
 {
@@ -526,6 +577,9 @@ show_ext_caps(struct device *d)
 	  case PCI_EXT_CAP_ID_LTR:
 	    cap_ltr(d, where);
 	    break;
+	  case PCI_EXT_CAP_ID_L1PM:
+	    cap_l1pm(d, where);
+	    break;
 	  default:
 	    printf("#%02x\n", id);
 	    break;
-- 
1.8.0