[RFC PATCH 3/3] PCI: Update bandwidth control and thermal cooling for Gen 7 (128 GT/s)
From: Ionut Nechita (Sunlight Linux)
Date: Tue Feb 17 2026 - 03:03:50 EST
From: Ionut Nechita <ionut_n2001@xxxxxxxxx>
Update PCIe subsystem components to support 128 GT/s link speed:
- bwctrl: Extend pcie_valid_speed() range to PCIE_SPEED_128_0GT,
add PCIE_SPEED_128_0GT to speed conversion table, widen
supported_speeds variables from u8 to u16
- portdrv: Switch hweight8() to hweight16() for supported_speeds
to match the widened type
- pcie_cooling: Add static_assert for PCIE_SPEED_128_0GT enum
contiguity check
Signed-off-by: Ionut Nechita <ionut_n2001@xxxxxxxxx>
---
drivers/pci/pcie/bwctrl.c | 7 ++++---
drivers/pci/pcie/portdrv.c | 2 +-
drivers/thermal/pcie_cooling.c | 1 +
3 files changed, 6 insertions(+), 4 deletions(-)
diff --git a/drivers/pci/pcie/bwctrl.c b/drivers/pci/pcie/bwctrl.c
index 36f939f23d34e..b9125b40cb860 100644
--- a/drivers/pci/pcie/bwctrl.c
+++ b/drivers/pci/pcie/bwctrl.c
@@ -50,7 +50,7 @@ static DECLARE_RWSEM(pcie_bwctrl_setspeed_rwsem);
static bool pcie_valid_speed(enum pci_bus_speed speed)
{
- return (speed >= PCIE_SPEED_2_5GT) && (speed <= PCIE_SPEED_64_0GT);
+ return (speed >= PCIE_SPEED_2_5GT) && (speed <= PCIE_SPEED_128_0GT);
}
static u16 pci_bus_speed2lnkctl2(enum pci_bus_speed speed)
@@ -62,6 +62,7 @@ static u16 pci_bus_speed2lnkctl2(enum pci_bus_speed speed)
[PCIE_SPEED_16_0GT] = PCI_EXP_LNKCTL2_TLS_16_0GT,
[PCIE_SPEED_32_0GT] = PCI_EXP_LNKCTL2_TLS_32_0GT,
[PCIE_SPEED_64_0GT] = PCI_EXP_LNKCTL2_TLS_64_0GT,
+ [PCIE_SPEED_128_0GT] = PCI_EXP_LNKCTL2_TLS_128_0GT,
};
if (WARN_ON_ONCE(!pcie_valid_speed(speed)))
@@ -70,7 +71,7 @@ static u16 pci_bus_speed2lnkctl2(enum pci_bus_speed speed)
return speed_conv[speed];
}
-static inline u16 pcie_supported_speeds2target_speed(u8 supported_speeds)
+static inline u16 pcie_supported_speeds2target_speed(u16 supported_speeds)
{
return __fls(supported_speeds);
}
@@ -88,7 +89,7 @@ static inline u16 pcie_supported_speeds2target_speed(u8 supported_speeds)
static u16 pcie_bwctrl_select_speed(struct pci_dev *port, enum pci_bus_speed speed_req)
{
struct pci_bus *bus = port->subordinate;
- u8 desired_speeds, supported_speeds;
+ u16 desired_speeds, supported_speeds;
struct pci_dev *dev;
desired_speeds = GENMASK(pci_bus_speed2lnkctl2(speed_req),
diff --git a/drivers/pci/pcie/portdrv.c b/drivers/pci/pcie/portdrv.c
index 38a41ccf79b9a..5ee8795107f26 100644
--- a/drivers/pci/pcie/portdrv.c
+++ b/drivers/pci/pcie/portdrv.c
@@ -274,7 +274,7 @@ static int get_port_device_capability(struct pci_dev *dev)
pcie_capability_read_dword(dev, PCI_EXP_LNKCAP, &linkcap);
if (linkcap & PCI_EXP_LNKCAP_LBNC &&
- hweight8(dev->supported_speeds) > 1)
+ hweight16(dev->supported_speeds) > 1)
services |= PCIE_PORT_SERVICE_BWCTRL;
}
diff --git a/drivers/thermal/pcie_cooling.c b/drivers/thermal/pcie_cooling.c
index a876d64f15827..9a2e39398674b 100644
--- a/drivers/thermal/pcie_cooling.c
+++ b/drivers/thermal/pcie_cooling.c
@@ -75,6 +75,7 @@ static_assert(PCIE_SPEED_5_0GT + 1 == PCIE_SPEED_8_0GT);
static_assert(PCIE_SPEED_8_0GT + 1 == PCIE_SPEED_16_0GT);
static_assert(PCIE_SPEED_16_0GT + 1 == PCIE_SPEED_32_0GT);
static_assert(PCIE_SPEED_32_0GT + 1 == PCIE_SPEED_64_0GT);
+static_assert(PCIE_SPEED_64_0GT + 1 == PCIE_SPEED_128_0GT);
MODULE_AUTHOR("Ilpo Järvinen <ilpo.jarvinen@xxxxxxxxxxxxxxx>");
MODULE_DESCRIPTION("PCIe cooling driver");
--
2.53.0