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Subject[PATCH v5 14/14] PCI: Remove unused pcie_get_minimum_link()
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From: Bjorn Helgaas <bhelgaas@google.com>

In some cases pcie_get_minimum_link() returned misleading information
because it found the slowest link and the narrowest link without
considering the total bandwidth of the link. For example, if the path
contained a 16 GT/s x1 link and a 2.5 GT/s x16 link,
pcie_get_minimum_link() returned 2.5 GT/s x1, which corresponds to 250 MB/s
of bandwidth, not the actual available bandwidth of about 2000 MB/s for a
16 GT/s x1 link.

Callers should use pcie_print_link_status() instead, or
pcie_bandwidth_available() if they need more detailed information.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
---
drivers/pci/pci.c | 43 -------------------------------------------
include/linux/pci.h | 2 --
2 files changed, 45 deletions(-)

diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index cec7aed09f6b..b6951c44ae6c 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -5103,49 +5103,6 @@ int pcie_set_mps(struct pci_dev *dev, int mps)
}
EXPORT_SYMBOL(pcie_set_mps);

-/**
- * pcie_get_minimum_link - determine minimum link settings of a PCI device
- * @dev: PCI device to query
- * @speed: storage for minimum speed
- * @width: storage for minimum width
- *
- * This function will walk up the PCI device chain and determine the minimum
- * link width and speed of the device.
- */
-int pcie_get_minimum_link(struct pci_dev *dev, enum pci_bus_speed *speed,
- enum pcie_link_width *width)
-{
- int ret;
-
- *speed = PCI_SPEED_UNKNOWN;
- *width = PCIE_LNK_WIDTH_UNKNOWN;
-
- while (dev) {
- u16 lnksta;
- enum pci_bus_speed next_speed;
- enum pcie_link_width next_width;
-
- ret = pcie_capability_read_word(dev, PCI_EXP_LNKSTA, &lnksta);
- if (ret)
- return ret;
-
- next_speed = pcie_link_speed[lnksta & PCI_EXP_LNKSTA_CLS];
- next_width = (lnksta & PCI_EXP_LNKSTA_NLW) >>
- PCI_EXP_LNKSTA_NLW_SHIFT;
-
- if (next_speed < *speed)
- *speed = next_speed;
-
- if (next_width < *width)
- *width = next_width;
-
- dev = dev->bus->self;
- }
-
- return 0;
-}
-EXPORT_SYMBOL(pcie_get_minimum_link);
-
/**
* pcie_bandwidth_available - determine minimum link settings of a PCIe
* device and its bandwidth limitation
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 38f7957121ef..5ccee29fe1b1 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -1081,8 +1081,6 @@ int pcie_get_readrq(struct pci_dev *dev);
int pcie_set_readrq(struct pci_dev *dev, int rq);
int pcie_get_mps(struct pci_dev *dev);
int pcie_set_mps(struct pci_dev *dev, int mps);
-int pcie_get_minimum_link(struct pci_dev *dev, enum pci_bus_speed *speed,
- enum pcie_link_width *width);
u32 pcie_bandwidth_available(struct pci_dev *dev, struct pci_dev **limiting_dev,
enum pci_bus_speed *speed,
enum pcie_link_width *width);
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