3 files changed, 53 insertions, 0 deletions

diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index e578d34095e9..12ba6351c05b 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -1566,6 +1566,7 @@ int pci_save_state(struct pci_dev *dev)
 	pci_save_ltr_state(dev);
 	pci_save_dpc_state(dev);
 	pci_save_aer_state(dev);
+	pci_save_ptm_state(dev);
 	return pci_save_vc_state(dev);
 }
 EXPORT_SYMBOL(pci_save_state);
@@ -1677,6 +1678,7 @@ void pci_restore_state(struct pci_dev *dev)
 	pci_restore_vc_state(dev);
 	pci_restore_rebar_state(dev);
 	pci_restore_dpc_state(dev);
+	pci_restore_ptm_state(dev);
 
 	pci_aer_clear_status(dev);
 	pci_restore_aer_state(dev);
diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
index f86cae9aa1f4..e0f9e7259e47 100644
--- a/drivers/pci/pci.h
+++ b/drivers/pci/pci.h
@@ -516,6 +516,14 @@ static inline int pci_iov_bus_range(struct pci_bus *bus)
 
 #endif /* CONFIG_PCI_IOV */
 
+#ifdef CONFIG_PCIE_PTM
+void pci_save_ptm_state(struct pci_dev *dev);
+void pci_restore_ptm_state(struct pci_dev *dev);
+#else
+static inline void pci_save_ptm_state(struct pci_dev *dev) { }
+static inline void pci_restore_ptm_state(struct pci_dev *dev) { }
+#endif
+
 unsigned long pci_cardbus_resource_alignment(struct resource *);
 
 static inline resource_size_t pci_resource_alignment(struct pci_dev *dev,
diff --git a/drivers/pci/pcie/ptm.c b/drivers/pci/pcie/ptm.c
index 357a454cafa0..6b24a1c9327a 100644
--- a/drivers/pci/pcie/ptm.c
+++ b/drivers/pci/pcie/ptm.c
@@ -29,6 +29,47 @@ static void pci_ptm_info(struct pci_dev *dev)
 		 dev->ptm_root ? " (root)" : "", clock_desc);
 }
 
+void pci_save_ptm_state(struct pci_dev *dev)
+{
+	int ptm;
+	struct pci_cap_saved_state *save_state;
+	u16 *cap;
+
+	if (!pci_is_pcie(dev))
+		return;
+
+	ptm = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_PTM);
+	if (!ptm)
+		return;
+
+	save_state = pci_find_saved_ext_cap(dev, PCI_EXT_CAP_ID_PTM);
+	if (!save_state) {
+		pci_err(dev, "no suspend buffer for PTM\n");
+		return;
+	}
+
+	cap = (u16 *)&save_state->cap.data[0];
+	pci_read_config_word(dev, ptm + PCI_PTM_CTRL, cap);
+}
+
+void pci_restore_ptm_state(struct pci_dev *dev)
+{
+	struct pci_cap_saved_state *save_state;
+	int ptm;
+	u16 *cap;
+
+	if (!pci_is_pcie(dev))
+		return;
+
+	save_state = pci_find_saved_ext_cap(dev, PCI_EXT_CAP_ID_PTM);
+	ptm = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_PTM);
+	if (!save_state || !ptm)
+		return;
+
+	cap = (u16 *)&save_state->cap.data[0];
+	pci_write_config_word(dev, ptm + PCI_PTM_CTRL, *cap);
+}
+
 void pci_ptm_init(struct pci_dev *dev)
 {
 	int pos;
@@ -65,6 +106,8 @@ void pci_ptm_init(struct pci_dev *dev)
 	if (!pos)
 		return;
 
+	pci_add_ext_cap_save_buffer(dev, PCI_EXT_CAP_ID_PTM, sizeof(u16));
+
 	pci_read_config_dword(dev, pos + PCI_PTM_CAP, &cap);
 	local_clock = (cap & PCI_PTM_GRANULARITY_MASK) >> 8;