[Qemu-devel] [PATCH 1/1] PCI Memory Mapping

[Brian Wheeler]

This patch
* modifies pci_to_cpu_addr() to support device-bus location mapping
* adds pci_register_physical_memory and pci_register_physical_memory_offset
* modifies cirrus_vga to use pci_register_physical_memory

The problem comes in with the alpha_softmmu target:  pci_mem_base isn't
a static offset.  On the alpha the base is defined as:
        
(0x80000000000ULL | (pci_dev->bus->bus_num * 0x200000000ULL) | addr

So, when a device is put into the system, its pci_mem_base address
depends on which bus it is put into.

This patch only handles cpu->pci memory access.  It doesn't do anything
with DMA operations by the device.

I'd really like some feedback on this, since its pretty important for
the alpha_softmmu target.

Thanks!
Brian

Signed-off-by: Brian Wheeler <address@hidden>
---------------
Index: hw/cirrus_vga.c
===================================================================
--- hw/cirrus_vga.c     (revision 7006)
+++ hw/cirrus_vga.c     (working copy)
@@ -3327,9 +3327,9 @@
     vga_dirty_log_stop((VGAState *)s);
 
     /* XXX: add byte swapping apertures */
-    cpu_register_physical_memory(addr, s->vram_size,
+    pci_register_physical_memory(d, addr, s->vram_size,
                                 s->cirrus_linear_io_addr);
-    cpu_register_physical_memory(addr + 0x1000000, 0x400000,
+    pci_register_physical_memory(d, addr + 0x1000000, 0x400000,
                                 s->cirrus_linear_bitblt_io_addr);
 
     s->map_addr = s->map_end = 0;
Index: hw/pci.c
===================================================================
--- hw/pci.c    (revision 7006)
+++ hw/pci.c    (working copy)
@@ -273,11 +273,29 @@
     return pci_dev;
 }
 
-static target_phys_addr_t pci_to_cpu_addr(target_phys_addr_t addr)
+static target_phys_addr_t pci_to_cpu_addr(PCIDevice *pci_dev, 
+                                         target_phys_addr_t addr)
 {
+#ifdef TARGET_ALPHA
+    return (0x80000000000ULL | (pci_dev->bus->bus_num * 0x200000000ULL) | addr;
+#else
     return addr + pci_mem_base;
+#endif
 }
 
+
+void pci_register_physical_memory_offset(PCIDevice *pci_dev,
+                                        target_phys_addr_t start_addr,
+                                         ram_addr_t size,
+                                         ram_addr_t phys_offset,
+                                         ram_addr_t region_offset)
+{
+  start_addr = pci_to_cpu_addr(pci_dev, start_addr);
+  cpu_register_physical_memory_offset(start_addr, size, phys_offset, 
+                                     region_offset);
+}
+
+
 static void pci_unregister_io_regions(PCIDevice *pci_dev)
 {
     PCIIORegion *r;
@@ -290,7 +308,7 @@
         if (r->type == PCI_ADDRESS_SPACE_IO) {
             isa_unassign_ioport(r->addr, r->size);
         } else {
-            cpu_register_physical_memory(pci_to_cpu_addr(r->addr),
+           cpu_register_physical_memory(pci_to_cpu_addr(pci_dev, r->addr),
                                                      r->size,
                                                      IO_MEM_UNASSIGNED);
         }
@@ -409,7 +427,8 @@
                             isa_unassign_ioport(r->addr, r->size);
                         }
                     } else {
-                        cpu_register_physical_memory(pci_to_cpu_addr(r->addr),
+                       cpu_register_physical_memory(pci_to_cpu_addr(d, 
+                                                                    r->addr),
                                                      r->size,
                                                      IO_MEM_UNASSIGNED);
                         qemu_unregister_coalesced_mmio(r->addr, r->size);
Index: hw/pci.h
===================================================================
--- hw/pci.h    (revision 7006)
+++ hw/pci.h    (working copy)
@@ -213,6 +213,25 @@
     cpu_to_le16wu((uint16_t *)&pci_config[PCI_CLASS_DEVICE], val);
 }
 
+
+
+void pci_register_physical_memory_offset(PCIDevice *pci_dev,
+                                        target_phys_addr_t start_addr,
+                                         ram_addr_t size,
+                                         ram_addr_t phys_offset,
+                                         ram_addr_t region_offset);
+static inline void pci_register_physical_memory(PCIDevice *pci_dev,
+                                               target_phys_addr_t start_addr,
+                                                ram_addr_t size,
+                                                ram_addr_t phys_offset)
+{
+    pci_register_physical_memory_offset(pci_dev, start_addr, size, 
+                                       phys_offset, 0);
+}
+
+
+
+
 /* lsi53c895a.c */
 #define LSI_MAX_DEVS 7
 void lsi_scsi_attach(void *opaque, BlockDriverState *bd, int id);