[Xen-devel] [PATCH v2 4/9] xen/pci: split code to size BARs from pci_add_device

[Roger Pau Monne <roger.pau@xxxxxxxxxx>]

So that it can be called from outside in order to get the size of regular PCI
BARs. This will be required in order to map the BARs from PCI devices into PVH
Dom0 p2m.

Signed-off-by: Roger Pau Monné <roger.pau@xxxxxxxxxx>
---
Cc: Jan Beulich <jbeulich@xxxxxxxx>
---
 xen/drivers/passthrough/pci.c | 86 ++++++++++++++++++++++++++-----------------
 xen/include/xen/pci.h         |  3 ++
 2 files changed, 56 insertions(+), 33 deletions(-)

diff --git a/xen/drivers/passthrough/pci.c b/xen/drivers/passthrough/pci.c
index 2288cf8814..7710c41533 100644
--- a/xen/drivers/passthrough/pci.c
+++ b/xen/drivers/passthrough/pci.c
@@ -588,6 +588,51 @@ static void pci_enable_acs(struct pci_dev *pdev)
     pci_conf_write16(seg, bus, dev, func, pos + PCI_ACS_CTRL, ctrl);
 }
 
+int pci_size_bar(unsigned int seg, unsigned int bus, unsigned int slot,
+                 unsigned int func, unsigned int base, unsigned int max_bars,
+                 unsigned int *index, uint64_t *addr, uint64_t *size)
+{
+    unsigned int idx = base + *index * 4;
+    u32 bar = pci_conf_read32(seg, bus, slot, func, idx);
+    u32 hi = 0;
+
+    *addr = *size = 0;
+
+    ASSERT((bar & PCI_BASE_ADDRESS_SPACE) == PCI_BASE_ADDRESS_SPACE_MEMORY);
+    pci_conf_write32(seg, bus, slot, func, idx, ~0);
+    if ( (bar & PCI_BASE_ADDRESS_MEM_TYPE_MASK) ==
+         PCI_BASE_ADDRESS_MEM_TYPE_64 )
+    {
+        if ( *index >= max_bars )
+        {
+            dprintk(XENLOG_WARNING,
+                    "device %04x:%02x:%02x.%u with 64-bit BAR in last slot\n",
+                    seg, bus, slot, func);
+            return -EINVAL;
+        }
+        hi = pci_conf_read32(seg, bus, slot, func, idx + 4);
+        pci_conf_write32(seg, bus, slot, func, idx + 4, ~0);
+    }
+    *size = pci_conf_read32(seg, bus, slot, func, idx) &
+            PCI_BASE_ADDRESS_MEM_MASK;
+    if ( (bar & PCI_BASE_ADDRESS_MEM_TYPE_MASK) ==
+         PCI_BASE_ADDRESS_MEM_TYPE_64 )
+    {
+        *size |= (u64)pci_conf_read32(seg, bus, slot, func, idx + 4) << 32;
+        pci_conf_write32(seg, bus, slot, func, idx + 4, hi);
+    }
+    else if ( *size )
+        *size |= (u64)~0 << 32;
+    pci_conf_write32(seg, bus, slot, func, idx, bar);
+    *size = -(*size);
+    *addr = (bar & PCI_BASE_ADDRESS_MEM_MASK) | ((u64)hi << 32);
+    if ( (bar & PCI_BASE_ADDRESS_MEM_TYPE_MASK) ==
+         PCI_BASE_ADDRESS_MEM_TYPE_64 )
+        ++*index;
+
+    return 0;
+}
+
 int pci_add_device(u16 seg, u8 bus, u8 devfn,
                    const struct pci_dev_info *info, nodeid_t node)
 {
@@ -652,7 +697,7 @@ int pci_add_device(u16 seg, u8 bus, u8 devfn,
             {
                 unsigned int idx = pos + PCI_SRIOV_BAR + i * 4;
                 u32 bar = pci_conf_read32(seg, bus, slot, func, idx);
-                u32 hi = 0;
+                uint64_t addr;
 
                 if ( (bar & PCI_BASE_ADDRESS_SPACE) ==
                      PCI_BASE_ADDRESS_SPACE_IO )
@@ -663,38 +708,13 @@ int pci_add_device(u16 seg, u8 bus, u8 devfn,
                            seg, bus, slot, func, i);
                     continue;
                 }
-                pci_conf_write32(seg, bus, slot, func, idx, ~0);
-                if ( (bar & PCI_BASE_ADDRESS_MEM_TYPE_MASK) ==
-                     PCI_BASE_ADDRESS_MEM_TYPE_64 )
-                {
-                    if ( i >= PCI_SRIOV_NUM_BARS )
-                    {
-                        printk(XENLOG_WARNING
-                               "SR-IOV device %04x:%02x:%02x.%u with 64-bit"
-                               " vf BAR in last slot\n",
-                               seg, bus, slot, func);
-                        break;
-                    }
-                    hi = pci_conf_read32(seg, bus, slot, func, idx + 4);
-                    pci_conf_write32(seg, bus, slot, func, idx + 4, ~0);
-                }
-                pdev->vf_rlen[i] = pci_conf_read32(seg, bus, slot, func, idx) &
-                                   PCI_BASE_ADDRESS_MEM_MASK;
-                if ( (bar & PCI_BASE_ADDRESS_MEM_TYPE_MASK) ==
-                     PCI_BASE_ADDRESS_MEM_TYPE_64 )
-                {
-                    pdev->vf_rlen[i] |= (u64)pci_conf_read32(seg, bus,
-                                                             slot, func,
-                                                             idx + 4) << 32;
-                    pci_conf_write32(seg, bus, slot, func, idx + 4, hi);
-                }
-                else if ( pdev->vf_rlen[i] )
-                    pdev->vf_rlen[i] |= (u64)~0 << 32;
-                pci_conf_write32(seg, bus, slot, func, idx, bar);
-                pdev->vf_rlen[i] = -pdev->vf_rlen[i];
-                if ( (bar & PCI_BASE_ADDRESS_MEM_TYPE_MASK) ==
-                     PCI_BASE_ADDRESS_MEM_TYPE_64 )
-                    ++i;
+                ret = pci_size_bar(seg, bus, slot, func, pos + PCI_SRIOV_BAR,
+                                   PCI_SRIOV_NUM_BARS, &i, &addr,
+                                   &pdev->vf_rlen[i]);
+                if ( ret )
+                    dprintk(XENLOG_WARNING,
+                            "%04x:%02x:%02x.%u: failed to size SR-IOV BAR%u\n",
+                            seg, bus, slot, func, i);
             }
         }
         else
diff --git a/xen/include/xen/pci.h b/xen/include/xen/pci.h
index a83c4a1276..3d3853fd6f 100644
--- a/xen/include/xen/pci.h
+++ b/xen/include/xen/pci.h
@@ -165,6 +165,9 @@ const char *parse_pci(const char *, unsigned int *seg, 
unsigned int *bus,
                       unsigned int *dev, unsigned int *func);
 const char *parse_pci_seg(const char *, unsigned int *seg, unsigned int *bus,
                           unsigned int *dev, unsigned int *func, bool 
*def_seg);
+int pci_size_bar(unsigned int seg, unsigned int bus, unsigned int slot,
+                 unsigned int func, unsigned int base, unsigned int max_bars,
+                 unsigned int *index, uint64_t *addr, uint64_t *size);
 
 
 bool_t pcie_aer_get_firmware_first(const struct pci_dev *);
-- 
2.11.0 (Apple Git-81)


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