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PCI/ATS: Use FIELD_GET()

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Use FIELD_GET() to remove dependences on the field position, i.e., the
shift value.  No functional change intended.

Link: https://lore.kernel.org/r/20231010204436.1000644-6-helgaas@kernel.org
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
This commit is contained in:
Bjorn Helgaas 2023-10-10 15:44:31 -05:00
parent d30fea2584
commit e0701bd0e6
2 changed files with 3 additions and 5 deletions
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7
drivers/pci/ats.c
View file

@ -9,6 +9,7 @@
* Copyright (C) 2011 Advanced Micro Devices,
*/
#include <linux/bitfield.h>
#include <linux/export.h>
#include <linux/pci-ats.h>
#include <linux/pci.h>
@ -480,8 +481,6 @@ int pci_pasid_features(struct pci_dev *pdev)
}
EXPORT_SYMBOL_GPL(pci_pasid_features);
#define PASID_NUMBER_SHIFT 8
#define PASID_NUMBER_MASK (0x1f << PASID_NUMBER_SHIFT)
/**
* pci_max_pasids - Get maximum number of PASIDs supported by device
* @pdev: PCI device structure
@ -503,9 +502,7 @@ int pci_max_pasids(struct pci_dev *pdev)
pci_read_config_word(pdev, pasid + PCI_PASID_CAP, &supported);
supported = (supported & PASID_NUMBER_MASK) >> PASID_NUMBER_SHIFT;
return (1 << supported);
return (1 << FIELD_GET(PCI_PASID_CAP_WIDTH, supported));
}
EXPORT_SYMBOL_GPL(pci_max_pasids);
#endif /* CONFIG_PCI_PASID */

1
include/uapi/linux/pci_regs.h
View file

@ -932,6 +932,7 @@
#define PCI_PASID_CAP 0x04 /* PASID feature register */
#define PCI_PASID_CAP_EXEC 0x0002 /* Exec permissions Supported */
#define PCI_PASID_CAP_PRIV 0x0004 /* Privilege Mode Supported */
#define PCI_PASID_CAP_WIDTH 0x1f00
#define PCI_PASID_CTRL 0x06 /* PASID control register */
#define PCI_PASID_CTRL_ENABLE 0x0001 /* Enable bit */
#define PCI_PASID_CTRL_EXEC 0x0002 /* Exec permissions Enable */