Initial import

1 files changed, 207 insertions, 0 deletions

diff --git a/drivers/xen/xen-pciback/conf_space_capability.c b/drivers/xen/xen-pciback/conf_space_capability.c
new file mode 100644
index 000000000..7f83e9083
--- /dev/null
+++ b/drivers/xen/xen-pciback/conf_space_capability.c
@@ -0,0 +1,207 @@
+/*
+ * 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;
+}