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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
commit5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch)
treea94efe259b9009378be6d90eb30d2b019d95c194 /drivers/xen/xen-pciback/conf_space_capability.c
parentInitial commit. (diff)
downloadlinux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.tar.xz
linux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.zip
Adding upstream version 5.10.209.upstream/5.10.209
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/xen/xen-pciback/conf_space_capability.c')
-rw-r--r--drivers/xen/xen-pciback/conf_space_capability.c305
1 files changed, 305 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..1948a9700
--- /dev/null
+++ b/drivers/xen/xen-pciback/conf_space_capability.c
@@ -0,0 +1,305 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * 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;
+
+ err = pci_read_config_word(dev, offset, &old_value);
+ if (err)
+ goto out;
+
+ 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 ? ERR_PTR(err) : NULL;
+}
+
+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 msi_msix_field_config {
+ u16 enable_bit; /* bit for enabling MSI/MSI-X */
+ u16 allowed_bits; /* bits allowed to be changed */
+ unsigned int int_type; /* interrupt type for exclusiveness check */
+} msi_field_config = {
+ .enable_bit = PCI_MSI_FLAGS_ENABLE,
+ .allowed_bits = PCI_MSI_FLAGS_ENABLE,
+ .int_type = INTERRUPT_TYPE_MSI,
+}, msix_field_config = {
+ .enable_bit = PCI_MSIX_FLAGS_ENABLE,
+ .allowed_bits = PCI_MSIX_FLAGS_ENABLE | PCI_MSIX_FLAGS_MASKALL,
+ .int_type = INTERRUPT_TYPE_MSIX,
+};
+
+static void *msi_field_init(struct pci_dev *dev, int offset)
+{
+ return &msi_field_config;
+}
+
+static void *msix_field_init(struct pci_dev *dev, int offset)
+{
+ return &msix_field_config;
+}
+
+static int msi_msix_flags_write(struct pci_dev *dev, int offset, u16 new_value,
+ void *data)
+{
+ int err;
+ u16 old_value;
+ const struct msi_msix_field_config *field_config = data;
+ const struct xen_pcibk_dev_data *dev_data = pci_get_drvdata(dev);
+
+ if (xen_pcibk_permissive || dev_data->permissive)
+ goto write;
+
+ err = pci_read_config_word(dev, offset, &old_value);
+ if (err)
+ return err;
+
+ if (new_value == old_value)
+ return 0;
+
+ if (!dev_data->allow_interrupt_control ||
+ (new_value ^ old_value) & ~field_config->allowed_bits)
+ return PCIBIOS_SET_FAILED;
+
+ if (new_value & field_config->enable_bit) {
+ /*
+ * Don't allow enabling together with other interrupt type, but do
+ * allow enabling MSI(-X) while INTx is still active to please Linuxes
+ * MSI(-X) startup sequence. It is safe to do, as according to PCI
+ * spec, device with enabled MSI(-X) shouldn't use INTx.
+ */
+ int int_type = xen_pcibk_get_interrupt_type(dev);
+
+ if (int_type == INTERRUPT_TYPE_NONE ||
+ int_type == INTERRUPT_TYPE_INTX ||
+ int_type == field_config->int_type)
+ goto write;
+ return PCIBIOS_SET_FAILED;
+ }
+
+write:
+ return pci_write_config_word(dev, offset, new_value);
+}
+
+static const struct config_field caplist_msix[] = {
+ {
+ .offset = PCI_MSIX_FLAGS,
+ .size = 2,
+ .init = msix_field_init,
+ .u.w.read = xen_pcibk_read_config_word,
+ .u.w.write = msi_msix_flags_write,
+ },
+ {}
+};
+
+static const struct config_field caplist_msi[] = {
+ {
+ .offset = PCI_MSI_FLAGS,
+ .size = 2,
+ .init = msi_field_init,
+ .u.w.read = xen_pcibk_read_config_word,
+ .u.w.write = msi_msix_flags_write,
+ },
+ {}
+};
+
+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,
+};
+static struct xen_pcibk_config_capability xen_pcibk_config_capability_msi = {
+ .capability = PCI_CAP_ID_MSI,
+ .fields = caplist_msi,
+};
+static struct xen_pcibk_config_capability xen_pcibk_config_capability_msix = {
+ .capability = PCI_CAP_ID_MSIX,
+ .fields = caplist_msix,
+};
+
+int xen_pcibk_config_capability_init(void)
+{
+ register_capability(&xen_pcibk_config_capability_vpd);
+ register_capability(&xen_pcibk_config_capability_pm);
+ register_capability(&xen_pcibk_config_capability_msi);
+ register_capability(&xen_pcibk_config_capability_msix);
+
+ return 0;
+}