Add PCIe 3.0+ decoding of the LnkCtl2 Compliance Preset/De-emphasis field

As of PCIe 3.0, the LnkCtl2 "Compliance De-emphasis" field has been
renamed to "Compliance Preset/De-emphasis", and there are several new
bit encodings for various de-emphasis and preshoot combinations.

The name of the PCI_EXP_LNKCTL2_COM_DEEMPHASIS() macro is not changed
by this commit, as it is part of the libpci API.

Reported-by: Tim CC Chen(陳志佳) <Tim.CC.Chen@wnc.com.tw>
Signed-off-by: Lennert Buytenhek <buytenh@arista.com>

diff --git a/lib/header.h b/lib/header.h
index 170e5c1812decc8859a8c38c9160a2ded45c0a7d..d4b40aad72f5e969d24a43725179fc1578be99dc 100644 (file)
--- a/lib/header.h
+++ b/lib/header.h
@@ -917,7 +917,7 @@
 #define  PCI_EXP_LNKCTL2_MARGIN(x)     (((x) >> 7) & 7) /* Transmit Margin */
 #define  PCI_EXP_LNKCTL2_MOD_CMPLNC    0x0400  /* Enter Modified Compliance */
 #define  PCI_EXP_LNKCTL2_CMPLNC_SOS    0x0800  /* Compliance SOS */
-#define  PCI_EXP_LNKCTL2_COM_DEEMPHASIS(x) (((x) >> 12) & 0xf) /* Compliance De-emphasis */
+#define  PCI_EXP_LNKCTL2_COM_DEEMPHASIS(x) (((x) >> 12) & 0xf) /* Compliance Preset/De-emphasis */
 #define PCI_EXP_LNKSTA2                        0x32    /* Link Status */
 #define  PCI_EXP_LINKSTA2_DEEMPHASIS(x)        ((x) & 1)       /* Current De-emphasis Level */
 #define  PCI_EXP_LINKSTA2_EQU_COMP     0x02    /* Equalization Complete */

diff --git a/ls-caps.c b/ls-caps.c
index 495d73a92e29b38aaf44aee91688f43a6e59ba1e..91acb59982ac2a32baafe9b81b584d5fdc004655 100644 (file)
--- a/ls-caps.c
+++ b/ls-caps.c
@@ -1233,6 +1233,35 @@ static const char *cap_express_link2_deemphasis(int type)
     }
 }
 
+static const char *cap_express_link2_compliance_preset(int type)
+{
+  switch (type)
+    {
+      case 0:
+       return "-6dB de-emphasis, 0dB preshoot";
+      case 1:
+       return "-3.5dB de-emphasis, 0dB preshoot";
+      case 2:
+       return "-4.4dB de-emphasis, 0dB preshoot";
+      case 3:
+       return "-2.5dB de-emphasis, 0dB preshoot";
+      case 4:
+       return "0dB de-emphasis, 0dB preshoot";
+      case 5:
+       return "0dB de-emphasis, 1.9dB preshoot";
+      case 6:
+       return "0dB de-emphasis, 2.5dB preshoot";
+      case 7:
+       return "-6.0dB de-emphasis, 3.5dB preshoot";
+      case 8:
+       return "-3.5dB de-emphasis, 3.5dB preshoot";
+      case 9:
+       return "0dB de-emphasis, 3.5dB preshoot";
+      default:
+       return "Unknown";
+    }
+}
+
 static const char *cap_express_link2_transmargin(int type)
 {
   switch (type)
@@ -1314,11 +1343,11 @@ static void cap_express_link2(struct device *d, int where, int type)
        cap_express_link2_deemphasis(PCI_EXP_LNKCTL2_DEEMPHASIS(w)));
     printf("\n"
        "\t\t\t Transmit Margin: %s, EnterModifiedCompliance%c ComplianceSOS%c\n"
-       "\t\t\t Compliance De-emphasis: %s\n",
+       "\t\t\t Compliance Preset/De-emphasis: %s\n",
        cap_express_link2_transmargin(PCI_EXP_LNKCTL2_MARGIN(w)),
        FLAG(w, PCI_EXP_LNKCTL2_MOD_CMPLNC),
        FLAG(w, PCI_EXP_LNKCTL2_CMPLNC_SOS),
-       cap_express_link2_deemphasis(PCI_EXP_LNKCTL2_COM_DEEMPHASIS(w)));
+       cap_express_link2_compliance_preset(PCI_EXP_LNKCTL2_COM_DEEMPHASIS(w)));
   }
 
   w = get_conf_word(d, where + PCI_EXP_LNKSTA2);