[PATCH 16/17] Handle PCIe ECAM space access from guests

["Thierry Escande" <thierry.escande@xxxxxxxxxx>]

This patch adds the logic to decode MMIO-based PCIe ECAM accesses. If
the IOREQ_TYPE_COPY request is within the ECAM address space configured
by hvmloader, the ioreq type is set to XEN_DMOP_IO_RANGE_PCI and the
sbdf decoded from the accessed address.

Signed-off-by: Thierry Escande <thierry.escande@xxxxxxxxxx>
---
 xen/arch/x86/hvm/ioreq.c | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/xen/arch/x86/hvm/ioreq.c b/xen/arch/x86/hvm/ioreq.c
index a5fa97e149..022fe05222 100644
--- a/xen/arch/x86/hvm/ioreq.c
+++ b/xen/arch/x86/hvm/ioreq.c
@@ -268,6 +268,8 @@ bool arch_ioreq_server_get_type_addr(const struct domain *d,
                                      uint64_t *addr)
 {
     unsigned int cf8 = d->arch.hvm.pci_cf8;
+    unsigned long mmio_start = (p->type == IOREQ_TYPE_COPY) ?
+                                ioreq_mmio_first_byte(p) : 0;
 
     if ( p->type != IOREQ_TYPE_COPY && p->type != IOREQ_TYPE_PIO )
         return false;
@@ -298,6 +300,19 @@ bool arch_ioreq_server_get_type_addr(const struct domain 
*d,
                 *addr |= CF8_ADDR_HI(cf8);
         }
     }
+    else if ( p->type == IOREQ_TYPE_COPY &&
+              (mmio_start >= d->arch.ecam_addr &&
+               mmio_start < (d->arch.ecam_addr + d->arch.ecam_size)) )
+    {
+        pci_sbdf_t sbdf;
+        unsigned int reg = mmio_start & ~PAGE_MASK;
+
+        sbdf.bdf =  (((mmio_start - d->arch.ecam_addr) & 0x0ffff000) >> 12);
+        sbdf.seg = 0;
+
+        *type = XEN_DMOP_IO_RANGE_PCI;
+        *addr = ((uint64_t)sbdf.sbdf << 32) | reg;
+    }
     else
     {
         *type = (p->type == IOREQ_TYPE_PIO) ?
-- 
2.51.0



--
Thierry Escande | Vates XCP-ng Developer

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