[PATCH][SRU Bionic] PCI: Add decoding for 16 GT/s link speed
dann frazier
dann.frazier at canonical.com
Fri May 25 19:32:16 UTC 2018
BugLink: https://bugs.launchpad.net/bugs/1773243
PCIe 4.0 defines the 16.0 GT/s link speed. Links can run at that speed
without any Linux changes, but previously their sysfs "max_link_speed" and
"current_link_speed" files contained "Unknown speed", not the expected
"16.0 GT/s".
Add decoding for the new 16 GT/s link speed.
Signed-off-by: Jay Fang <f.fangjian at huawei.com>
[bhelgaas: add PCI_EXP_LNKCAP2_SLS_16_0GB]
Signed-off-by: Bjorn Helgaas <bhelgaas at google.com>
Reviewed-by: Dongdong Liu <liudongdong3 at huawei.com>
(cherry picked from commit 1acfb9b7ee0b1881bb8e875b6757976e48293ec4)
Signed-off-by: dann frazier <dann.frazier at canonical.com>
---
drivers/pci/pci-sysfs.c | 6 ++++++
drivers/pci/probe.c | 2 +-
drivers/pci/slot.c | 1 +
include/linux/pci.h | 1 +
include/uapi/linux/pci_regs.h | 7 +++++--
5 files changed, 14 insertions(+), 3 deletions(-)
diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c
index b7b4486c2755..612e523551f8 100644
--- a/drivers/pci/pci-sysfs.c
+++ b/drivers/pci/pci-sysfs.c
@@ -168,6 +168,9 @@ static ssize_t max_link_speed_show(struct device *dev,
return -EINVAL;
switch (linkcap & PCI_EXP_LNKCAP_SLS) {
+ case PCI_EXP_LNKCAP_SLS_16_0GB:
+ speed = "16 GT/s";
+ break;
case PCI_EXP_LNKCAP_SLS_8_0GB:
speed = "8 GT/s";
break;
@@ -213,6 +216,9 @@ static ssize_t current_link_speed_show(struct device *dev,
return -EINVAL;
switch (linkstat & PCI_EXP_LNKSTA_CLS) {
+ case PCI_EXP_LNKSTA_CLS_16_0GB:
+ speed = "16 GT/s";
+ break;
case PCI_EXP_LNKSTA_CLS_8_0GB:
speed = "8 GT/s";
break;
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index 070476036846..d0e7608dcb98 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -587,7 +587,7 @@ const unsigned char pcie_link_speed[] = {
PCIE_SPEED_2_5GT, /* 1 */
PCIE_SPEED_5_0GT, /* 2 */
PCIE_SPEED_8_0GT, /* 3 */
- PCI_SPEED_UNKNOWN, /* 4 */
+ PCIE_SPEED_16_0GT, /* 4 */
PCI_SPEED_UNKNOWN, /* 5 */
PCI_SPEED_UNKNOWN, /* 6 */
PCI_SPEED_UNKNOWN, /* 7 */
diff --git a/drivers/pci/slot.c b/drivers/pci/slot.c
index e42909524dee..7569e4e3a8a4 100644
--- a/drivers/pci/slot.c
+++ b/drivers/pci/slot.c
@@ -75,6 +75,7 @@ static const char *pci_bus_speed_strings[] = {
"2.5 GT/s PCIe", /* 0x14 */
"5.0 GT/s PCIe", /* 0x15 */
"8.0 GT/s PCIe", /* 0x16 */
+ "16.0 GT/s PCIe", /* 0x17 */
};
static ssize_t bus_speed_read(enum pci_bus_speed speed, char *buf)
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 0962a3a36d62..5320e9757219 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -259,6 +259,7 @@ enum pci_bus_speed {
PCIE_SPEED_2_5GT = 0x14,
PCIE_SPEED_5_0GT = 0x15,
PCIE_SPEED_8_0GT = 0x16,
+ PCIE_SPEED_16_0GT = 0x17,
PCI_SPEED_UNKNOWN = 0xff,
};
diff --git a/include/uapi/linux/pci_regs.h b/include/uapi/linux/pci_regs.h
index 70c2b2ade048..271f8f89f015 100644
--- a/include/uapi/linux/pci_regs.h
+++ b/include/uapi/linux/pci_regs.h
@@ -520,6 +520,7 @@
#define PCI_EXP_LNKCAP_SLS_2_5GB 0x00000001 /* LNKCAP2 SLS Vector bit 0 */
#define PCI_EXP_LNKCAP_SLS_5_0GB 0x00000002 /* LNKCAP2 SLS Vector bit 1 */
#define PCI_EXP_LNKCAP_SLS_8_0GB 0x00000003 /* LNKCAP2 SLS Vector bit 2 */
+#define PCI_EXP_LNKCAP_SLS_16_0GB 0x00000004 /* LNKCAP2 SLS Vector bit 3 */
#define PCI_EXP_LNKCAP_MLW 0x000003f0 /* Maximum Link Width */
#define PCI_EXP_LNKCAP_ASPMS 0x00000c00 /* ASPM Support */
#define PCI_EXP_LNKCAP_L0SEL 0x00007000 /* L0s Exit Latency */
@@ -547,6 +548,7 @@
#define PCI_EXP_LNKSTA_CLS_2_5GB 0x0001 /* Current Link Speed 2.5GT/s */
#define PCI_EXP_LNKSTA_CLS_5_0GB 0x0002 /* Current Link Speed 5.0GT/s */
#define PCI_EXP_LNKSTA_CLS_8_0GB 0x0003 /* Current Link Speed 8.0GT/s */
+#define PCI_EXP_LNKSTA_CLS_16_0GB 0x0004 /* Current Link Speed 16.0GT/s */
#define PCI_EXP_LNKSTA_NLW 0x03f0 /* Negotiated Link Width */
#define PCI_EXP_LNKSTA_NLW_X1 0x0010 /* Current Link Width x1 */
#define PCI_EXP_LNKSTA_NLW_X2 0x0020 /* Current Link Width x2 */
@@ -644,8 +646,9 @@
#define PCI_CAP_EXP_RC_ENDPOINT_SIZEOF_V2 44 /* v2 endpoints without link end here */
#define PCI_EXP_LNKCAP2 44 /* Link Capabilities 2 */
#define PCI_EXP_LNKCAP2_SLS_2_5GB 0x00000002 /* Supported Speed 2.5GT/s */
-#define PCI_EXP_LNKCAP2_SLS_5_0GB 0x00000004 /* Supported Speed 5.0GT/s */
-#define PCI_EXP_LNKCAP2_SLS_8_0GB 0x00000008 /* Supported Speed 8.0GT/s */
+#define PCI_EXP_LNKCAP2_SLS_5_0GB 0x00000004 /* Supported Speed 5GT/s */
+#define PCI_EXP_LNKCAP2_SLS_8_0GB 0x00000008 /* Supported Speed 8GT/s */
+#define PCI_EXP_LNKCAP2_SLS_16_0GB 0x00000010 /* Supported Speed 16GT/s */
#define PCI_EXP_LNKCAP2_CROSSLINK 0x00000100 /* Crosslink supported */
#define PCI_EXP_LNKCTL2 48 /* Link Control 2 */
#define PCI_EXP_LNKSTA2 50 /* Link Status 2 */
--
2.17.0
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