platform/x86: ISST: Remove 8 socket limit

Stop restricting the PCI search to a range of PCI domains fed to
pci_get_domain_bus_and_slot().  Instead, use for_each_pci_dev() and
look at all PCI domains in one pass.

On systems with more than 8 sockets, this avoids error messages like
"Information: Invalid level, Can't get TDP control information at
specified levels on cpu 480" from the intel speed select utility.

Fixes: aa2ddd242572 ("platform/x86: ISST: Use numa node id for cpu pci dev mapping")
Signed-off-by: Steve Wahl <steve.wahl@hpe.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20230519160420.2588475-1-steve.wahl@hpe.com
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
diff --git a/drivers/platform/x86/intel/speed_select_if/isst_if_common.c b/drivers/platform/x86/intel/speed_select_if/isst_if_common.c
index e0572a2..02fe360 100644
--- a/drivers/platform/x86/intel/speed_select_if/isst_if_common.c
+++ b/drivers/platform/x86/intel/speed_select_if/isst_if_common.c
@@ -304,14 +304,13 @@ struct isst_if_pkg_info {
 static struct isst_if_cpu_info *isst_cpu_info;
 static struct isst_if_pkg_info *isst_pkg_info;
 
-#define ISST_MAX_PCI_DOMAINS	8
-
 static struct pci_dev *_isst_if_get_pci_dev(int cpu, int bus_no, int dev, int fn)
 {
 	struct pci_dev *matched_pci_dev = NULL;
 	struct pci_dev *pci_dev = NULL;
+	struct pci_dev *_pci_dev = NULL;
 	int no_matches = 0, pkg_id;
-	int i, bus_number;
+	int bus_number;
 
 	if (bus_no < 0 || bus_no >= ISST_MAX_BUS_NUMBER || cpu < 0 ||
 	    cpu >= nr_cpu_ids || cpu >= num_possible_cpus())
@@ -323,12 +322,11 @@ static struct pci_dev *_isst_if_get_pci_dev(int cpu, int bus_no, int dev, int fn
 	if (bus_number < 0)
 		return NULL;
 
-	for (i = 0; i < ISST_MAX_PCI_DOMAINS; ++i) {
-		struct pci_dev *_pci_dev;
+	for_each_pci_dev(_pci_dev) {
 		int node;
 
-		_pci_dev = pci_get_domain_bus_and_slot(i, bus_number, PCI_DEVFN(dev, fn));
-		if (!_pci_dev)
+		if (_pci_dev->bus->number != bus_number ||
+		    _pci_dev->devfn != PCI_DEVFN(dev, fn))
 			continue;
 
 		++no_matches;