PCI/PTM: Save/restore Precision Time Measurement Capability for suspend/resume

[linux-2.6-microblaze.git] / drivers / pci / pcie / ptm.c

diff --git a/drivers/pci/pcie/ptm.c b/drivers/pci/pcie/ptm.c
index 357a454..6b24a1c 100644 (file)
--- 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;