[PATCH AUTOSEL 6.5 23/34] PCI: Use FIELD_GET() to extract Link Width

Sasha Levin
2023-11-07T16:10:40Z

From: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>

[ Upstream commit d1f9b39da4a5347150246871325190018cda8cb3 ]

Use FIELD_GET() to extract PCIe Negotiated and Maximum Link Width fields
instead of custom masking and shifting.

Link: https://lore.kernel.org/r/20230919125648.1920-7-ilpo.jarvinen@linux.intel.com
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
[bhelgaas: drop duplicate include of <linux/bitfield.h>]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/pci/pci-sysfs.c | 5 ++---
drivers/pci/pci.c | 5 ++---
2 files changed, 4 insertions(+), 6 deletions(-)

diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c
index ab32a91f287b4..4473773dc2af4 100644
--- a/drivers/pci/pci-sysfs.c
+++ b/drivers/pci/pci-sysfs.c
@@ -12,7 +12,7 @@
* Modeled after usb's driverfs.c
*/

-
+#include <linux/bitfield.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/pci.h>
@@ -230,8 +230,7 @@ static ssize_t current_link_width_show(struct device *dev,
if (err)
return -EINVAL;

- return sysfs_emit(buf, "%u\n",
- (linkstat & PCI_EXP_LNKSTA_NLW) >> PCI_EXP_LNKSTA_NLW_SHIFT);
+ return sysfs_emit(buf, "%u\n", FIELD_GET(PCI_EXP_LNKSTA_NLW, linkstat));
}
static DEVICE_ATTR_RO(current_link_width);

diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 3cd907eb67b74..2c5662d43df1b 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -6255,8 +6255,7 @@ u32 pcie_bandwidth_available(struct pci_dev *dev, struct pci_dev **limiting_dev,
pcie_capability_read_word(dev, PCI_EXP_LNKSTA, &lnksta);

next_speed = pcie_link_speed[lnksta & PCI_EXP_LNKSTA_CLS];
- next_width = (lnksta & PCI_EXP_LNKSTA_NLW) >>
- PCI_EXP_LNKSTA_NLW_SHIFT;
+ next_width = FIELD_GET(PCI_EXP_LNKSTA_NLW, lnksta);

next_bw = next_width * PCIE_SPEED2MBS_ENC(next_speed);

@@ -6328,7 +6327,7 @@ enum pcie_link_width pcie_get_width_cap(struct pci_dev *dev)

pcie_capability_read_dword(dev, PCI_EXP_LNKCAP, &lnkcap);
if (lnkcap)
- return (lnkcap & PCI_EXP_LNKCAP_MLW) >> 4;
+ return FIELD_GET(PCI_EXP_LNKCAP_MLW, lnkcap);

return PCIE_LNK_WIDTH_UNKNOWN;
}
--
2.42.0