--- /dev/null
+/*
+ * PCI Backend - Handles the virtual fields found on the capability lists
+ * in the configuration space.
+ *
+ * Author: Ryan Wilson <hap9@epoch.ncsc.mil>
+ */
+
+#include <linux/kernel.h>
+#include <linux/pci.h>
+#include "pciback.h"
+#include "conf_space.h"
+
+static LIST_HEAD(capabilities);
+struct xen_pcibk_config_capability {
+ struct list_head cap_list;
+
+ int capability;
+
+ /* If the device has the capability found above, add these fields */
+ const struct config_field *fields;
+};
+
+static const struct config_field caplist_header[] = {
+ {
+ .offset = PCI_CAP_LIST_ID,
+ .size = 2, /* encompass PCI_CAP_LIST_ID & PCI_CAP_LIST_NEXT */
+ .u.w.read = xen_pcibk_read_config_word,
+ .u.w.write = NULL,
+ },
+ {}
+};
+
+static inline void register_capability(struct xen_pcibk_config_capability *cap)
+{
+ list_add_tail(&cap->cap_list, &capabilities);
+}
+
+int xen_pcibk_config_capability_add_fields(struct pci_dev *dev)
+{
+ int err = 0;
+ struct xen_pcibk_config_capability *cap;
+ int cap_offset;
+
+ list_for_each_entry(cap, &capabilities, cap_list) {
+ cap_offset = pci_find_capability(dev, cap->capability);
+ if (cap_offset) {
+ dev_dbg(&dev->dev, "Found capability 0x%x at 0x%x\n",
+ cap->capability, cap_offset);
+
+ err = xen_pcibk_config_add_fields_offset(dev,
+ caplist_header,
+ cap_offset);
+ if (err)
+ goto out;
+ err = xen_pcibk_config_add_fields_offset(dev,
+ cap->fields,
+ cap_offset);
+ if (err)
+ goto out;
+ }
+ }
+
+out:
+ return err;
+}
+
+static int vpd_address_write(struct pci_dev *dev, int offset, u16 value,
+ void *data)
+{
+ /* Disallow writes to the vital product data */
+ if (value & PCI_VPD_ADDR_F)
+ return PCIBIOS_SET_FAILED;
+ else
+ return pci_write_config_word(dev, offset, value);
+}
+
+static const struct config_field caplist_vpd[] = {
+ {
+ .offset = PCI_VPD_ADDR,
+ .size = 2,
+ .u.w.read = xen_pcibk_read_config_word,
+ .u.w.write = vpd_address_write,
+ },
+ {
+ .offset = PCI_VPD_DATA,
+ .size = 4,
+ .u.dw.read = xen_pcibk_read_config_dword,
+ .u.dw.write = NULL,
+ },
+ {}
+};
+
+static int pm_caps_read(struct pci_dev *dev, int offset, u16 *value,
+ void *data)
+{
+ int err;
+ u16 real_value;
+
+ err = pci_read_config_word(dev, offset, &real_value);
+ if (err)
+ goto out;
+
+ *value = real_value & ~PCI_PM_CAP_PME_MASK;
+
+out:
+ return err;
+}
+
+/* PM_OK_BITS specifies the bits that the driver domain is allowed to change.
+ * Can't allow driver domain to enable PMEs - they're shared */
+#define PM_OK_BITS (PCI_PM_CTRL_PME_STATUS|PCI_PM_CTRL_DATA_SEL_MASK)
+
+static int pm_ctrl_write(struct pci_dev *dev, int offset, u16 new_value,
+ void *data)
+{
+ int err;
+ u16 old_value;
+ pci_power_t new_state, old_state;
+
+ err = pci_read_config_word(dev, offset, &old_value);
+ if (err)
+ goto out;
+
+ old_state = (pci_power_t)(old_value & PCI_PM_CTRL_STATE_MASK);
+ new_state = (pci_power_t)(new_value & PCI_PM_CTRL_STATE_MASK);
+
+ new_value &= PM_OK_BITS;
+ if ((old_value & PM_OK_BITS) != new_value) {
+ new_value = (old_value & ~PM_OK_BITS) | new_value;
+ err = pci_write_config_word(dev, offset, new_value);
+ if (err)
+ goto out;
+ }
+
+ /* Let pci core handle the power management change */
+ dev_dbg(&dev->dev, "set power state to %x\n", new_state);
+ err = pci_set_power_state(dev, new_state);
+ if (err) {
+ err = PCIBIOS_SET_FAILED;
+ goto out;
+ }
+
+ out:
+ return err;
+}
+
+/* Ensure PMEs are disabled */
+static void *pm_ctrl_init(struct pci_dev *dev, int offset)
+{
+ int err;
+ u16 value;
+
+ err = pci_read_config_word(dev, offset, &value);
+ if (err)
+ goto out;
+
+ if (value & PCI_PM_CTRL_PME_ENABLE) {
+ value &= ~PCI_PM_CTRL_PME_ENABLE;
+ err = pci_write_config_word(dev, offset, value);
+ }
+
+out:
+ return ERR_PTR(err);
+}
+
+static const struct config_field caplist_pm[] = {
+ {
+ .offset = PCI_PM_PMC,
+ .size = 2,
+ .u.w.read = pm_caps_read,
+ },
+ {
+ .offset = PCI_PM_CTRL,
+ .size = 2,
+ .init = pm_ctrl_init,
+ .u.w.read = xen_pcibk_read_config_word,
+ .u.w.write = pm_ctrl_write,
+ },
+ {
+ .offset = PCI_PM_PPB_EXTENSIONS,
+ .size = 1,
+ .u.b.read = xen_pcibk_read_config_byte,
+ },
+ {
+ .offset = PCI_PM_DATA_REGISTER,
+ .size = 1,
+ .u.b.read = xen_pcibk_read_config_byte,
+ },
+ {}
+};
+
+static struct xen_pcibk_config_capability xen_pcibk_config_capability_pm = {
+ .capability = PCI_CAP_ID_PM,
+ .fields = caplist_pm,
+};
+static struct xen_pcibk_config_capability xen_pcibk_config_capability_vpd = {
+ .capability = PCI_CAP_ID_VPD,
+ .fields = caplist_vpd,
+};
+
+int xen_pcibk_config_capability_init(void)
+{
+ register_capability(&xen_pcibk_config_capability_vpd);
+ register_capability(&xen_pcibk_config_capability_pm);
+
+ return 0;
+}
Code Review / kvmfornfv.git / blobdiff