@@ -39,30 +39,38 @@ int pci_find_cap_offset(pci_sbdf_t sbdf, u8 cap)
return 0;
}
-int pci_find_next_cap(pci_sbdf_t sbdf, u8 pos, int cap)
+uint8_t pci_find_next_cap_ttl(pci_sbdf_t sbdf, uint8_t pos,
+ bool (*is_match)(uint8_t), unsigned int *ttl)
{
- u8 id;
- int ttl = 48;
+ uint8_t id;
- while ( ttl-- )
+ while ( (*ttl)-- )
{
pos = pci_conf_read8(sbdf, pos);
if ( pos < 0x40 )
break;
- pos &= ~3;
- id = pci_conf_read8(sbdf, pos + PCI_CAP_LIST_ID);
+ id = pci_conf_read8(sbdf, (pos & ~3) + PCI_CAP_LIST_ID);
if ( id == 0xff )
break;
- if ( id == cap )
+ if ( is_match(id) )
return pos;
- pos += PCI_CAP_LIST_NEXT;
+ pos = (pos & ~3) + PCI_CAP_LIST_NEXT;
}
+
return 0;
}
+uint8_t pci_find_next_cap(pci_sbdf_t sbdf, uint8_t pos,
+ bool (*is_match)(uint8_t))
+{
+ unsigned int ttl = 48;
+
+ return pci_find_next_cap_ttl(sbdf, pos, is_match, &ttl) & ~3;
+}
+
/**
* pci_find_ext_capability - Find an extended capability
* @sbdf: PCI device to query
@@ -513,6 +513,18 @@ static void cf_check rom_write(
rom->addr = val & PCI_ROM_ADDRESS_MASK;
}
+static bool cf_check vpci_cap_supported(uint8_t id)
+{
+ switch ( id )
+ {
+ case PCI_CAP_ID_MSI:
+ case PCI_CAP_ID_MSIX:
+ return true;
+ default:
+ return false;
+ }
+}
+
static int cf_check init_bars(struct pci_dev *pdev)
{
uint16_t cmd;
@@ -544,6 +556,63 @@ static int cf_check init_bars(struct pci_dev *pdev)
if ( rc )
return rc;
+ if ( !is_hardware_domain(pdev->domain) )
+ {
+ if ( !(pci_conf_read16(pdev->sbdf, PCI_STATUS) & PCI_STATUS_CAP_LIST) )
+ {
+ /* RAZ/WI */
+ rc = vpci_add_register(pdev->vpci, vpci_read_val, NULL,
+ PCI_CAPABILITY_LIST, 1, (void *)0);
+ if ( rc )
+ return rc;
+ }
+ else
+ {
+ /* Only expose capabilities to the guest that vPCI can handle. */
+ uint8_t next;
+ unsigned int ttl = 48;
+
+ next = pci_find_next_cap_ttl(pdev->sbdf, PCI_CAPABILITY_LIST,
+ vpci_cap_supported, &ttl);
+
+ rc = vpci_add_register(pdev->vpci, vpci_read_val, NULL,
+ PCI_CAPABILITY_LIST, 1,
+ (void *)(uintptr_t)next);
+ if ( rc )
+ return rc;
+
+ next &= ~3;
+
+ while ( next && ttl )
+ {
+ uint8_t pos = next;
+
+ next = pci_find_next_cap_ttl(pdev->sbdf,
+ pos + PCI_CAP_LIST_NEXT,
+ vpci_cap_supported, &ttl);
+
+ rc = vpci_add_register(pdev->vpci, vpci_hw_read8, NULL,
+ pos + PCI_CAP_LIST_ID, 1, NULL);
+ if ( rc )
+ return rc;
+
+ rc = vpci_add_register(pdev->vpci, vpci_read_val, NULL,
+ pos + PCI_CAP_LIST_NEXT, 1,
+ (void *)(uintptr_t)next);
+ if ( rc )
+ return rc;
+
+ next &= ~3;
+ }
+ }
+
+ /* Extended capabilities RAZ/WI */
+ rc = vpci_add_register(pdev->vpci, vpci_read_val, NULL, 0x100, 4,
+ (void *)0);
+ if ( rc )
+ return rc;
+ }
+
if ( pdev->ignore_bars )
return 0;
@@ -133,6 +133,18 @@ static void cf_check vpci_ignored_write(
{
}
+uint32_t cf_check vpci_read_val(
+ const struct pci_dev *pdev, unsigned int reg, void *data)
+{
+ return (uintptr_t)data;
+}
+
+uint32_t cf_check vpci_hw_read8(
+ const struct pci_dev *pdev, unsigned int reg, void *data)
+{
+ return pci_conf_read8(pdev->sbdf, reg);
+}
+
uint32_t cf_check vpci_hw_read16(
const struct pci_dev *pdev, unsigned int reg, void *data)
{
@@ -194,7 +194,10 @@ int pci_mmcfg_read(unsigned int seg, unsigned int bus,
int pci_mmcfg_write(unsigned int seg, unsigned int bus,
unsigned int devfn, int reg, int len, u32 value);
int pci_find_cap_offset(pci_sbdf_t sbdf, u8 cap);
-int pci_find_next_cap(pci_sbdf_t sbdf, u8 pos, int cap);
+uint8_t pci_find_next_cap_ttl(pci_sbdf_t sbdf, uint8_t pos,
+ bool (*is_match)(uint8_t), unsigned int *ttl);
+uint8_t pci_find_next_cap(pci_sbdf_t sbdf, uint8_t pos,
+ bool (*is_match)(uint8_t));
int pci_find_ext_capability(pci_sbdf_t sbdf, int cap);
int pci_find_next_ext_capability(pci_sbdf_t sbdf, int start, int cap);
const char *parse_pci(const char *, unsigned int *seg, unsigned int *bus,
@@ -45,7 +45,12 @@ uint32_t vpci_read(pci_sbdf_t sbdf, unsigned int reg, unsigned int size);
void vpci_write(pci_sbdf_t sbdf, unsigned int reg, unsigned int size,
uint32_t data);
+uint32_t cf_check vpci_read_val(
+ const struct pci_dev *pdev, unsigned int reg, void *data);
+
/* Passthrough handlers. */
+uint32_t cf_check vpci_hw_read8(
+ const struct pci_dev *pdev, unsigned int reg, void *data);
uint32_t cf_check vpci_hw_read16(
const struct pci_dev *pdev, unsigned int reg, void *data);
uint32_t cf_check vpci_hw_read32(
Currently, Xen vPCI only supports virtualizing the MSI and MSI-X capabilities. Hide all other PCI capabilities (including extended capabilities) from domUs for now, even though there may be certain devices/drivers that depend on being able to discover certain capabilities. We parse the physical PCI capabilities linked list and add vPCI register handlers for the next elements, inserting our own next value, thus presenting a modified linked list to the domU. Introduce helper functions vpci_hw_read8 and vpci_read_val. The vpci_read_val helper function returns a fixed value, which may be used for RAZ registers, or registers whose value doesn't change. Introduce pci_find_next_cap_ttl() helper while adapting the logic from pci_find_next_cap() to suit our needs, and implement the existing pci_find_next_cap() in terms of the new helper. Signed-off-by: Stewart Hildebrand <stewart.hildebrand@amd.com> --- v2->v3: * get rid of > 0 in loop condition * implement pci_find_next_cap in terms of new pci_find_next_cap_ttl function so that hypothetical future callers wouldn't be required to pass &ttl. * change NULL to (void *)0 for RAZ value passed to vpci_read_val * change type of ttl to unsigned int * remember to mask off the low 2 bits of next in the initial loop iteration * change return type of pci_find_next_cap and pci_find_next_cap_ttl * avoid wrapping the PCI_STATUS_CAP_LIST condition by using ! instead of == 0 v1->v2: * change type of ttl to int * use switch statement instead of if/else * adapt existing pci_find_next_cap helper instead of rolling our own * pass ttl as in/out * "pass through" the lower 2 bits of the next pointer * squash helper functions into this patch to avoid transient dead code situation * extended capabilities RAZ/WI --- xen/drivers/pci/pci.c | 24 +++++++++----- xen/drivers/vpci/header.c | 69 +++++++++++++++++++++++++++++++++++++++ xen/drivers/vpci/vpci.c | 12 +++++++ xen/include/xen/pci.h | 5 ++- xen/include/xen/vpci.h | 5 +++ 5 files changed, 106 insertions(+), 9 deletions(-)