From b56a5a23bfecd9cac9187164a9d5f22d287c48b9 Mon Sep 17 00:00:00 2001 From: "Michael S. Tsirkin" Date: Mon, 21 Aug 2006 16:22:22 +0300 Subject: [PATCH] PCI: Restore PCI Express capability registers after PM event Restore PCI Express capability registers after PM event. This includes maxumum MTU for PCI express and other vital data. Signed-off-by: Michael S. Tsirkin Signed-off-by: Greg Kroah-Hartman --- drivers/pci/pci.c | 50 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 50 insertions(+) diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 590f4e6f505..a544997399b 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -445,6 +445,51 @@ pci_power_t pci_choose_state(struct pci_dev *dev, pm_message_t state) EXPORT_SYMBOL(pci_choose_state); +static int pci_save_pcie_state(struct pci_dev *dev) +{ + int pos, i = 0; + struct pci_cap_saved_state *save_state; + u16 *cap; + + pos = pci_find_capability(dev, PCI_CAP_ID_EXP); + if (pos <= 0) + return 0; + + save_state = kzalloc(sizeof(*save_state) + sizeof(u16) * 4, GFP_KERNEL); + if (!save_state) { + dev_err(&dev->dev, "Out of memory in pci_save_pcie_state\n"); + return -ENOMEM; + } + cap = (u16 *)&save_state->data[0]; + + pci_read_config_word(dev, pos + PCI_EXP_DEVCTL, &cap[i++]); + pci_read_config_word(dev, pos + PCI_EXP_LNKCTL, &cap[i++]); + pci_read_config_word(dev, pos + PCI_EXP_SLTCTL, &cap[i++]); + pci_read_config_word(dev, pos + PCI_EXP_RTCTL, &cap[i++]); + pci_add_saved_cap(dev, save_state); + return 0; +} + +static void pci_restore_pcie_state(struct pci_dev *dev) +{ + int i = 0, pos; + struct pci_cap_saved_state *save_state; + u16 *cap; + + save_state = pci_find_saved_cap(dev, PCI_CAP_ID_EXP); + pos = pci_find_capability(dev, PCI_CAP_ID_EXP); + if (!save_state || pos <= 0) + return; + cap = (u16 *)&save_state->data[0]; + + pci_write_config_word(dev, pos + PCI_EXP_DEVCTL, cap[i++]); + pci_write_config_word(dev, pos + PCI_EXP_LNKCTL, cap[i++]); + pci_write_config_word(dev, pos + PCI_EXP_SLTCTL, cap[i++]); + pci_write_config_word(dev, pos + PCI_EXP_RTCTL, cap[i++]); + pci_remove_saved_cap(save_state); + kfree(save_state); +} + /** * pci_save_state - save the PCI configuration space of a device before suspending * @dev: - PCI device that we're dealing with @@ -460,6 +505,8 @@ pci_save_state(struct pci_dev *dev) return i; if ((i = pci_save_msix_state(dev)) != 0) return i; + if ((i = pci_save_pcie_state(dev)) != 0) + return i; return 0; } @@ -473,6 +520,9 @@ pci_restore_state(struct pci_dev *dev) int i; int val; + /* PCI Express register must be restored first */ + pci_restore_pcie_state(dev); + /* * The Base Address register should be programmed before the command * register(s) -- 2.41.1