[PATCH v2 03/11] vpci/header: Move register assignments from init_bars

[Oleksandr Andrushchenko <andr2000@gmail.com>]

From: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>

This is in preparation for dynamic assignment of the vPCI register
handlers depending on the domain: hwdom or guest.
The need for this step is that it is easier to have all related functionality
put at one place. When the subsequent patches add decisions on which
handlers to install, e.g. hwdom or guest handlers, then this is easily
achievable.

Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>

---
Since v1:
 - constify struct pci_dev where possible
 - extend patch description
---
 xen/drivers/vpci/header.c | 83 ++++++++++++++++++++++++++-------------
 1 file changed, 56 insertions(+), 27 deletions(-)

diff --git a/xen/drivers/vpci/header.c b/xen/drivers/vpci/header.c
index f8cd55e7c024..3d571356397a 100644
--- a/xen/drivers/vpci/header.c
+++ b/xen/drivers/vpci/header.c
@@ -445,6 +445,55 @@ static void rom_write(const struct pci_dev *pdev, unsigned int reg,
         rom->addr = val & PCI_ROM_ADDRESS_MASK;
 }
 
+static int add_bar_handlers(const struct pci_dev *pdev)
+{
+    unsigned int i;
+    struct vpci_header *header = &pdev->vpci->header;
+    struct vpci_bar *bars = header->bars;
+    int rc;
+
+    /* Setup a handler for the command register. */
+    rc = vpci_add_register(pdev->vpci, vpci_hw_read16, cmd_write, PCI_COMMAND,
+                           2, header);
+    if ( rc )
+        return rc;
+
+    if ( pdev->ignore_bars )
+        return 0;
+
+    for ( i = 0; i < PCI_HEADER_NORMAL_NR_BARS + 1; i++ )
+    {
+        if ( (bars[i].type == VPCI_BAR_IO) || (bars[i].type == VPCI_BAR_EMPTY) )
+            continue;
+
+        if ( bars[i].type == VPCI_BAR_ROM )
+        {
+            unsigned int rom_reg;
+            uint8_t header_type = pci_conf_read8(pdev->sbdf,
+                                                 PCI_HEADER_TYPE) & 0x7f;
+            if ( header_type == PCI_HEADER_TYPE_NORMAL )
+                rom_reg = PCI_ROM_ADDRESS;
+            else
+                rom_reg = PCI_ROM_ADDRESS1;
+            rc = vpci_add_register(pdev->vpci, vpci_hw_read32, rom_write,
+                                   rom_reg, 4, &bars[i]);
+            if ( rc )
+                return rc;
+        }
+        else
+        {
+            uint8_t reg = PCI_BASE_ADDRESS_0 + i * 4;
+
+            /* This is either VPCI_BAR_MEM32 or VPCI_BAR_MEM64_{LO|HI}. */
+            rc = vpci_add_register(pdev->vpci, vpci_hw_read32, bar_write, reg,
+                                   4, &bars[i]);
+            if ( rc )
+                return rc;
+        }
+    }
+    return 0;
+}
+
 static int init_bars(struct pci_dev *pdev)
 {
     uint16_t cmd;
@@ -470,14 +519,8 @@ static int init_bars(struct pci_dev *pdev)
         return -EOPNOTSUPP;
     }
 
-    /* Setup a handler for the command register. */
-    rc = vpci_add_register(pdev->vpci, vpci_hw_read16, cmd_write, PCI_COMMAND,
-                           2, header);
-    if ( rc )
-        return rc;
-
     if ( pdev->ignore_bars )
-        return 0;
+        return add_bar_handlers(pdev);
 
     /* Disable memory decoding before sizing. */
     cmd = pci_conf_read16(pdev->sbdf, PCI_COMMAND);
@@ -492,14 +535,6 @@ static int init_bars(struct pci_dev *pdev)
         if ( i && bars[i - 1].type == VPCI_BAR_MEM64_LO )
         {
             bars[i].type = VPCI_BAR_MEM64_HI;
-            rc = vpci_add_register(pdev->vpci, vpci_hw_read32, bar_write, reg,
-                                   4, &bars[i]);
-            if ( rc )
-            {
-                pci_conf_write16(pdev->sbdf, PCI_COMMAND, cmd);
-                return rc;
-            }
-
             continue;
         }
 
@@ -532,14 +567,6 @@ static int init_bars(struct pci_dev *pdev)
         bars[i].addr = addr;
         bars[i].size = size;
         bars[i].prefetchable = val & PCI_BASE_ADDRESS_MEM_PREFETCH;
-
-        rc = vpci_add_register(pdev->vpci, vpci_hw_read32, bar_write, reg, 4,
-                               &bars[i]);
-        if ( rc )
-        {
-            pci_conf_write16(pdev->sbdf, PCI_COMMAND, cmd);
-            return rc;
-        }
     }
 
     /* Check expansion ROM. */
@@ -553,11 +580,13 @@ static int init_bars(struct pci_dev *pdev)
         rom->addr = addr;
         header->rom_enabled = pci_conf_read32(pdev->sbdf, rom_reg) &
                               PCI_ROM_ADDRESS_ENABLE;
+    }
 
-        rc = vpci_add_register(pdev->vpci, vpci_hw_read32, rom_write, rom_reg,
-                               4, rom);
-        if ( rc )
-            rom->type = VPCI_BAR_EMPTY;
+    rc = add_bar_handlers(pdev);
+    if ( rc )
+    {
+        pci_conf_write16(pdev->sbdf, PCI_COMMAND, cmd);
+        return rc;
     }
 
     return (cmd & PCI_COMMAND_MEMORY) ? modify_bars(pdev, cmd, false) : 0;
-- 
2.25.1