PCI: Add decoding for 16 GT/s link speed

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@huawei.com>
[bhelgaas: add PCI_EXP_LNKCAP2_SLS_16_0GB]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Dongdong Liu <liudongdong3@huawei.com>

diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c
index eb6bee8..7dc5be5 100644 (file)
--- 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 ef53774..86bf045 100644 (file)
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -592,7 +592,7 @@ 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 d10f556..191893e 100644 (file)
--- a/drivers/pci/slot.c
+++ b/drivers/pci/slot.c
@@ -76,6 +76,7 @@ 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 024a1be..8043a59 100644 (file)
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -256,6 +256,7 @@ 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 0c79eac..103ba79 100644 (file)
--- 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 */
@@ -648,8 +650,9 @@
 #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 */