[PATCH v2] PCI: Add PCIe 5.0 data rate (32 GT/s) support
From: Gustavo Pimentel
Date: Tue Jun 04 2019 - 12:28:45 EST
PCIe 5.0 allows an effective 32.0 GT/s speed per lane.
Currently if you read a PCIe 5.0 EP link data rate through sysfs, the
resulting output will be "Unknown speed" instead of "32.0 GT/s" as we
would be expect.
Signed-off-by: Gustavo Pimentel <gustavo.pimentel@xxxxxxxxxxxx>
---
Changes:
v1 -> v2
- Rebase patch
drivers/pci/pci-sysfs.c | 3 +++
drivers/pci/pci.c | 4 +++-
drivers/pci/probe.c | 2 +-
drivers/pci/slot.c | 1 +
include/linux/pci.h | 1 +
include/uapi/linux/pci_regs.h | 4 ++++
6 files changed, 13 insertions(+), 2 deletions(-)
diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c
index 6d27475..d52d304 100644
--- a/drivers/pci/pci-sysfs.c
+++ b/drivers/pci/pci-sysfs.c
@@ -182,6 +182,9 @@ static ssize_t current_link_speed_show(struct device *dev,
return -EINVAL;
switch (linkstat & PCI_EXP_LNKSTA_CLS) {
+ case PCI_EXP_LNKSTA_CLS_32_0GB:
+ speed = "32 GT/s";
+ break;
case PCI_EXP_LNKSTA_CLS_16_0GB:
speed = "16 GT/s";
break;
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 8abc843..4729a7c 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -5621,7 +5621,9 @@ enum pci_bus_speed pcie_get_speed_cap(struct pci_dev *dev)
*/
pcie_capability_read_dword(dev, PCI_EXP_LNKCAP2, &lnkcap2);
if (lnkcap2) { /* PCIe r3.0-compliant */
- if (lnkcap2 & PCI_EXP_LNKCAP2_SLS_16_0GB)
+ if (lnkcap2 & PCI_EXP_LNKCAP2_SLS_32_0GB)
+ return PCIE_SPEED_32_0GT;
+ else if (lnkcap2 & PCI_EXP_LNKCAP2_SLS_16_0GB)
return PCIE_SPEED_16_0GT;
else if (lnkcap2 & PCI_EXP_LNKCAP2_SLS_8_0GB)
return PCIE_SPEED_8_0GT;
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index 0e8e2c1..c5f27c8 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -668,7 +668,7 @@ const unsigned char pcie_link_speed[] = {
PCIE_SPEED_5_0GT, /* 2 */
PCIE_SPEED_8_0GT, /* 3 */
PCIE_SPEED_16_0GT, /* 4 */
- PCI_SPEED_UNKNOWN, /* 5 */
+ PCIE_SPEED_32_0GT, /* 5 */
PCI_SPEED_UNKNOWN, /* 6 */
PCI_SPEED_UNKNOWN, /* 7 */
PCI_SPEED_UNKNOWN, /* 8 */
diff --git a/drivers/pci/slot.c b/drivers/pci/slot.c
index f4d92b1..ae4aa0e 100644
--- a/drivers/pci/slot.c
+++ b/drivers/pci/slot.c
@@ -75,6 +75,7 @@ static const char *pci_bus_speed_strings[] = {
"5.0 GT/s PCIe", /* 0x15 */
"8.0 GT/s PCIe", /* 0x16 */
"16.0 GT/s PCIe", /* 0x17 */
+ "32.0 GT/s PCIe", /* 0x18 */
};
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 4a5a84d..2173e6b 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -258,6 +258,7 @@ enum pci_bus_speed {
PCIE_SPEED_5_0GT = 0x15,
PCIE_SPEED_8_0GT = 0x16,
PCIE_SPEED_16_0GT = 0x17,
+ PCIE_SPEED_32_0GT = 0x18,
PCI_SPEED_UNKNOWN = 0xff,
};
diff --git a/include/uapi/linux/pci_regs.h b/include/uapi/linux/pci_regs.h
index 2716476..f28e562 100644
--- a/include/uapi/linux/pci_regs.h
+++ b/include/uapi/linux/pci_regs.h
@@ -528,6 +528,7 @@
#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_SLS_32_0GB 0x00000005 /* LNKCAP2 SLS Vector bit 4 */
#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 */
@@ -556,6 +557,7 @@
#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_CLS_32_0GB 0x0005 /* Current Link Speed 32.0GT/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 */
@@ -661,6 +663,7 @@
#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_SLS_32_0GB 0x00000020 /* Supported Speed 32GT/s */
#define PCI_EXP_LNKCAP2_CROSSLINK 0x00000100 /* Crosslink supported */
#define PCI_EXP_LNKCTL2 48 /* Link Control 2 */
#define PCI_EXP_LNKCTL2_TLS 0x000f
@@ -668,6 +671,7 @@
#define PCI_EXP_LNKCTL2_TLS_5_0GT 0x0002 /* Supported Speed 5GT/s */
#define PCI_EXP_LNKCTL2_TLS_8_0GT 0x0003 /* Supported Speed 8GT/s */
#define PCI_EXP_LNKCTL2_TLS_16_0GT 0x0004 /* Supported Speed 16GT/s */
+#define PCI_EXP_LNKCTL2_TLS_32_0GT 0x0005 /* Supported Speed 32GT/s */
#define PCI_EXP_LNKSTA2 50 /* Link Status 2 */
#define PCI_CAP_EXP_ENDPOINT_SIZEOF_V2 52 /* v2 endpoints with link end here */
#define PCI_EXP_SLTCAP2 52 /* Slot Capabilities 2 */
--
2.7.4