[PATCH 1/3] PCI/IDE: Add/export mini helpers for platform TSM drivers

[Xu Yilun <yilun.xu@linux.intel.com>]

These mini helpers are mainly for platform TSM drivers to setup root
port side configuration. Root port side IDE settings may require
platform specific firmware calls (e.g. TDX Connect [1]) so could not use
pci_ide_stream_setup(), but may still share these mini helpers cause
they also refer to definitions in IDE specification.

[1]: https://lore.kernel.org/linux-coco/20250919142237.418648-28-dan.j.williams@intel.com/

Signed-off-by: Xu Yilun <yilun.xu@linux.intel.com>
---
 include/linux/pci-ide.h | 6 ++++++
 drivers/pci/ide.c       | 8 +++-----
 2 files changed, 9 insertions(+), 5 deletions(-)

diff --git a/include/linux/pci-ide.h b/include/linux/pci-ide.h
index a30f9460b04a..5adbd8b81f65 100644
--- a/include/linux/pci-ide.h
+++ b/include/linux/pci-ide.h
@@ -6,6 +6,11 @@
 #ifndef __PCI_IDE_H__
 #define __PCI_IDE_H__
 
+#define PREP_PCI_IDE_SEL_RID_2(base, domain)               \
+	(FIELD_PREP(PCI_IDE_SEL_RID_2_VALID, 1) |          \
+	 FIELD_PREP(PCI_IDE_SEL_RID_2_BASE, (base)) | \
+	 FIELD_PREP(PCI_IDE_SEL_RID_2_SEG, (domain)))
+
 enum pci_ide_partner_select {
 	PCI_IDE_EP,
 	PCI_IDE_RP,
@@ -61,6 +66,7 @@ struct pci_ide {
 	struct tsm_dev *tsm_dev;
 };
 
+int pci_ide_domain(struct pci_dev *pdev);
 struct pci_ide_partner *pci_ide_to_settings(struct pci_dev *pdev, struct pci_ide *ide);
 struct pci_ide *pci_ide_stream_alloc(struct pci_dev *pdev);
 void pci_ide_stream_free(struct pci_ide *ide);
diff --git a/drivers/pci/ide.c b/drivers/pci/ide.c
index 10603f2d2319..7633b8e52399 100644
--- a/drivers/pci/ide.c
+++ b/drivers/pci/ide.c
@@ -345,12 +345,13 @@ void pci_ide_stream_unregister(struct pci_ide *ide)
 }
 EXPORT_SYMBOL_GPL(pci_ide_stream_unregister);
 
-static int pci_ide_domain(struct pci_dev *pdev)
+int pci_ide_domain(struct pci_dev *pdev)
 {
 	if (pdev->fm_enabled)
 		return pci_domain_nr(pdev->bus);
 	return 0;
 }
+EXPORT_SYMBOL_GPL(pci_ide_domain);
 
 struct pci_ide_partner *pci_ide_to_settings(struct pci_dev *pdev, struct pci_ide *ide)
 {
@@ -420,10 +421,7 @@ void pci_ide_stream_setup(struct pci_dev *pdev, struct pci_ide *ide)
 	val = FIELD_PREP(PCI_IDE_SEL_RID_1_LIMIT, settings->rid_end);
 	pci_write_config_dword(pdev, pos + PCI_IDE_SEL_RID_1, val);
 
-	val = FIELD_PREP(PCI_IDE_SEL_RID_2_VALID, 1) |
-	      FIELD_PREP(PCI_IDE_SEL_RID_2_BASE, settings->rid_start) |
-	      FIELD_PREP(PCI_IDE_SEL_RID_2_SEG, pci_ide_domain(pdev));
-
+	val = PREP_PCI_IDE_SEL_RID_2(settings->rid_start, pci_ide_domain(pdev));
 	pci_write_config_dword(pdev, pos + PCI_IDE_SEL_RID_2, val);
 
 	/*
-- 
2.25.1