[PATCH 1/3] PCI: Remove unused PCI_SUBTRACTIVE_DECODE

Ilpo Järvinen
2024-10-17T14:11:25Z

The commit 2fe2abf896c1 ("PCI: augment bus resource table with a list")
added PCI_SUBTRACTIVE_DECODE which is put into the struct
pci_bus_resource flags field but is never read. There seems to never
have been users for it. Remove both PCI_SUBTRACTIVE_DECODE and the
flags field from the struct pci_bus_resource.

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
---
arch/s390/pci/pci_bus.c | 2 +-
arch/x86/pci/fixup.c | 2 +-
drivers/pci/bus.c | 4 +---
drivers/pci/probe.c | 5 ++---
include/linux/pci.h | 12 +-----------
5 files changed, 6 insertions(+), 19 deletions(-)

diff --git a/arch/s390/pci/pci_bus.c b/arch/s390/pci/pci_bus.c
index daa5d7450c7d..5630af5deb8b 100644
--- a/arch/s390/pci/pci_bus.c
+++ b/arch/s390/pci/pci_bus.c
@@ -53,7 +53,7 @@ static int zpci_bus_prepare_device(struct zpci_dev *zdev)
zpci_setup_bus_resources(zdev);
for (i = 0; i < PCI_STD_NUM_BARS; i++) {
if (zdev->bars[i].res)
- pci_bus_add_resource(zdev->zbus->bus, zdev->bars[i].res, 0);
+ pci_bus_add_resource(zdev->zbus->bus, zdev->bars[i].res);
}
}

diff --git a/arch/x86/pci/fixup.c b/arch/x86/pci/fixup.c
index 98a9bb92d75c..0681ecfe3430 100644
--- a/arch/x86/pci/fixup.c
+++ b/arch/x86/pci/fixup.c
@@ -757,7 +757,7 @@ static void pci_amd_enable_64bit_bar(struct pci_dev *dev)
dev_info(&dev->dev, "adding root bus resource %pR (tainting kernel)\n",
res);
add_taint(TAINT_FIRMWARE_WORKAROUND, LOCKDEP_STILL_OK);
- pci_bus_add_resource(dev->bus, res, 0);
+ pci_bus_add_resource(dev->bus, res);
}

base = ((res->start >> 8) & AMD_141b_MMIO_BASE_MMIOBASE_MASK) |
diff --git a/drivers/pci/bus.c b/drivers/pci/bus.c
index 55c853686051..9cf6d0f3ab2b 100644
--- a/drivers/pci/bus.c
+++ b/drivers/pci/bus.c
@@ -46,8 +46,7 @@ void pci_free_resource_list(struct list_head *resources)
}
EXPORT_SYMBOL(pci_free_resource_list);

-void pci_bus_add_resource(struct pci_bus *bus, struct resource *res,
- unsigned int flags)
+void pci_bus_add_resource(struct pci_bus *bus, struct resource *res)
{
struct pci_bus_resource *bus_res;

@@ -58,7 +57,6 @@ void pci_bus_add_resource(struct pci_bus *bus, struct resource *res,
}

bus_res->res = res;
- bus_res->flags = flags;
list_add_tail(&bus_res->list, &bus->resources);
}

diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index 4f68414c3086..4243b1e6ece2 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -546,8 +546,7 @@ void pci_read_bridge_bases(struct pci_bus *child)
if (dev->transparent) {
pci_bus_for_each_resource(child->parent, res) {
if (res && res->flags) {
- pci_bus_add_resource(child, res,
- PCI_SUBTRACTIVE_DECODE);
+ pci_bus_add_resource(child, res);
pci_info(dev, " bridge window %pR (subtractive decode)\n",
res);
}
@@ -1032,7 +1031,7 @@ static int pci_register_host_bridge(struct pci_host_bridge *bridge)
if (res->flags & IORESOURCE_BUS)
pci_bus_insert_busn_res(bus, bus->number, res->end);
else
- pci_bus_add_resource(bus, res, 0);
+ pci_bus_add_resource(bus, res);

if (offset) {
if (resource_type(res) == IORESOURCE_IO)
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 573b4c4c2be6..6a9cf80d0d4b 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -633,18 +633,9 @@ int pcibios_root_bridge_prepare(struct pci_host_bridge *bridge);
* Use pci_bus_for_each_resource() to iterate through all the resources.
*/

-/*
- * PCI_SUBTRACTIVE_DECODE means the bridge forwards the window implicitly
- * and there's no way to program the bridge with the details of the window.
- * This does not apply to ACPI _CRS windows, even with the _DEC subtractive-
- * decode bit set, because they are explicit and can be programmed with _SRS.
- */
-#define PCI_SUBTRACTIVE_DECODE 0x1
-
struct pci_bus_resource {
struct list_head list;
struct resource *res;
- unsigned int flags;
};

#define PCI_REGION_FLAG_MASK 0x0fU /* These bits of resource flags tell us the PCI region flags */
@@ -1498,8 +1489,7 @@ void pci_add_resource(struct list_head *resources, struct resource *res);
void pci_add_resource_offset(struct list_head *resources, struct resource *res,
resource_size_t offset);
void pci_free_resource_list(struct list_head *resources);
-void pci_bus_add_resource(struct pci_bus *bus, struct resource *res,
- unsigned int flags);
+void pci_bus_add_resource(struct pci_bus *bus, struct resource *res);
struct resource *pci_bus_resource_n(const struct pci_bus *bus, int n);
void pci_bus_remove_resources(struct pci_bus *bus);
void pci_bus_remove_resource(struct pci_bus *bus, struct resource *res);
--
2.39.5