RFC: arm: pci: Add PCI cam support to PCI-E ecam driver

When booting U-Boot in crosvm, the virtual machine emulates a PCI cam
device, not the PCI-E 'ecam' device normally seen on e.g. QEMU. This
PCI device can be supported with only trivial changes to the ecam
driver.

Instead of adding a completely new driver which is identical besides the
initialization step, add support for the PCI version to the existing
driver.

Signed-off-by: Alistair Delva <adelva@google.com>
Cc: Tuomas Tynkkynen <tuomas.tynkkynen@iki.fi>
Cc: Ram Muthiah <rammuthiah@google.com>

diff --git a/drivers/pci/pcie_ecam_generic.c b/drivers/pci/pcie_ecam_generic.c
index 09b6fc1..1a9f9ae 100644 (file)
--- a/drivers/pci/pcie_ecam_generic.c
+++ b/drivers/pci/pcie_ecam_generic.c
@@ -14,6 +14,8 @@
 
 #include <asm/io.h>
 
+#define TYPE_PCI 0x1
+
 /**
  * struct generic_ecam_pcie - generic_ecam PCIe controller state
  * @cfg_base: The base address of memory mapped configuration space
@@ -46,8 +48,14 @@ static int pci_generic_ecam_conf_address(const struct udevice *bus,
        void *addr;
 
        addr = pcie->cfg_base;
-       addr += PCIE_ECAM_OFFSET(PCI_BUS(bdf) - pcie->first_busno,
-                                PCI_DEV(bdf), PCI_FUNC(bdf), offset);
+
+       if (dev_get_driver_data(bus) == TYPE_PCI) {
+               addr += ((PCI_BUS(bdf) - pcie->first_busno) << 16) |
+                        (PCI_DEV(bdf) << 11) | (PCI_FUNC(bdf) << 8) | offset;
+       } else {
+               addr += PCIE_ECAM_OFFSET(PCI_BUS(bdf) - pcie->first_busno,
+                                        PCI_DEV(bdf), PCI_FUNC(bdf), offset);
+       }
        *paddress = addr;
 
        return 0;
@@ -156,7 +164,8 @@ static const struct dm_pci_ops pci_generic_ecam_ops = {
 };
 
 static const struct udevice_id pci_generic_ecam_ids[] = {
-       { .compatible = "pci-host-ecam-generic" },
+       { .compatible = "pci-host-ecam-generic" /* PCI-E */ },
+       { .compatible = "pci-host-cam-generic", .data = TYPE_PCI },
        { }
 };