[PATCHv2] pci: load memory window setup from host - SeaBIOS

30 Apr 2013

Load memory window setup for pci from host.
This makes it possible for host to make sure
setup matches hardware exactly: especially important
for when ACPI tables are loaded from host.
This will also make it easier to add more chipsets
down the road.
Signed-off-by: Michael S. Tsirkin mst@redhat.com
---
Changes from v1:
    - fix bug in 64 bit range check
    - address Kevin's comments:
    	move file load into pciinit.c
    	dont reorder initialization
    	sizeof style fix
src/pciinit.c | 91 ++++++++++++++++++++++++++++++++++++++++++++++++-----------
 1 file changed, 75 insertions(+), 16 deletions(-)

diff --git a/src/pciinit.c b/src/pciinit.c
index bb9355f..a4a5bf5 100644
--- a/src/pciinit.c
+++ b/src/pciinit.c
@@ -13,6 +13,7 @@
 #include "config.h" // CONFIG_*
 #include "memmap.h" // add_e820
 #include "paravirt.h" // RamSize
+#include "byteorder.h" // le64_to_cpu
 #include "dev-q35.h"
/* PM Timer ticks per second (HZ) */
@@ -61,6 +62,13 @@ struct pci_bus {
     struct pci_device *bus_dev;
 };
+struct pci_mem {
+	u64 start32;
+	u64 end32;
+	u64 start64;
+	u64 end64;
+};
+
 static u32 pci_bar(struct pci_device *pci, int region_num)
 {
     if (region_num != PCI_ROM_SLOT) {
@@ -361,6 +369,8 @@ static void pci_enable_default_vga(void)
void i440fx_mem_addr_setup(struct pci_device *dev, void *arg)
 {
+    if (arg)
+	/* use supplied memory */;
     if (RamSize <= 0x80000000)
         pcimem_start = 0x80000000;
     else if (RamSize <= 0xc0000000)
@@ -383,8 +393,9 @@ void mch_mem_addr_setup(struct pci_device *dev, void *arg)
     pci_config_writel(bdf, Q35_HOST_BRIDGE_PCIEXBAR, lower);
     add_e820(addr, size, E820_RESERVED);
-    /* setup pci i/o window (above mmconfig) */
-    pcimem_start = addr + size;
+    /* unless done already, setup pci i/o window (above mmconfig) */
+    if (!arg)
+    	pcimem_start = addr + size;
pci_slot_get_irq = mch_pci_slot_get_irq;
 }
@@ -397,11 +408,11 @@ static const struct pci_device_id pci_platform_tbl[] = {
     PCI_DEVICE_END
 };
-static void pci_bios_init_platform(void)
+static void pci_bios_init_platform(struct pci_mem *mem)
 {
     struct pci_device *pci;
     foreachpci(pci) {
-        pci_init_device(pci_platform_tbl, pci, NULL);
+        pci_init_device(pci_platform_tbl, pci, mem);
     }
 }
@@ -762,10 +773,14 @@ static void pci_region_map_entries(struct pci_bus *busses, struct pci_region *r)
     }
 }
-static void pci_bios_map_devices(struct pci_bus *busses)
+static void pci_bios_map_devices(struct pci_bus *busses, struct pci_mem *mem)
 {
     if (pci_bios_init_root_regions(busses)) {
         struct pci_region r64_mem, r64_pref;
+
+        if (mem && mem->start64 >= mem->end64)
+            panic("PCI: out of 32bit address space\n");
+
         r64_mem.list = NULL;
         r64_pref.list = NULL;
         pci_region_migrate_64bit_entries(&busses[0].r[PCI_REGION_TYPE_MEM],
@@ -781,14 +796,27 @@ static void pci_bios_map_devices(struct pci_bus *busses)
         u64 align_mem = pci_region_align(&r64_mem);
         u64 align_pref = pci_region_align(&r64_pref);
-        r64_mem.base = ALIGN(0x100000000LL + RamSizeOver4G, align_mem);
-        r64_pref.base = ALIGN(r64_mem.base + sum_mem, align_pref);
-        pcimem64_start = r64_mem.base;
-        pcimem64_end = r64_pref.base + sum_pref;
+        if (mem) {
+            /*
+             * Non prefetcheable memory at start of the window,
+             * prefetcheable memory at the end.
+             * This way OS has the maximum flexibility for
+             * allocating the rest of the memory.
+             */
+            r64_mem.base = ALIGN(mem->start64, align_mem);
+            r64_pref.base = ALIGN_DOWN(mem->end64 - sum_pref + 1, align_pref);
+            if (sum_pref && r64_pref.base < r64_mem.base + sum_mem)
+                panic("PCI: out of 64bit address space\n");
+        } else {
+            r64_mem.base = ALIGN(0x100000000LL + RamSizeOver4G, align_mem);
+            r64_pref.base = ALIGN(r64_mem.base + sum_mem, align_pref);
+            pcimem64_start = r64_mem.base;
+            pcimem64_end = r64_pref.base + sum_pref;
+        }
pci_region_map_entries(busses, &r64_mem);
         pci_region_map_entries(busses, &r64_pref);
-    } else {
+    } else if (!mem) {
         // no bars mapped high -> drop 64bit window (see dsdt)
         pcimem64_start = 0;
     }
@@ -801,11 +829,28 @@ static void pci_bios_map_devices(struct pci_bus *busses)
     }
 }
+static
+struct pci_mem *pci_mem_get(void)
+{
+    int psize;
+    struct pci_mem *mem = romfile_loadfile("etc/pci-info", &psize);
+    if (!mem)
+        return NULL;
+    if (psize < sizeof(*mem)) {
+        free(mem);
+        return NULL;
+    }
+    mem->start32 = le64_to_cpu(mem->start32);
+    mem->end32 = le64_to_cpu(mem->end32);
+    mem->start64 = le64_to_cpu(mem->start64);
+    mem->end64 = le64_to_cpu(mem->end64);
+    return mem;
+}
+
/****************************************************************
  * Main setup code
  ****************************************************************/
-
 void
 pci_setup(void)
 {
@@ -823,25 +868,39 @@ pci_setup(void)
     dprintf(1, "=== PCI device probing ===\n");
     pci_probe_devices();
-    pcimem_start = RamSize;
-    pci_bios_init_platform();
+    struct pci_mem *mem = pci_mem_get();
+
+    if (mem) {
+        pcimem_start = mem->start32;
+        pcimem_end = mem->end32;
+        pcimem64_start = mem->start64;
+        pcimem64_end = mem->end64;
+    } else {
+        pcimem_start = RamSize;
+    }
+
+    pci_bios_init_platform(mem);
dprintf(1, "=== PCI new allocation pass #1 ===\n");
     struct pci_bus *busses = malloc_tmp(sizeof(*busses) * (MaxPCIBus + 1));
     if (!busses) {
         warn_noalloc();
-        return;
+        goto done;
     }
     memset(busses, 0, sizeof(*busses) * (MaxPCIBus + 1));
     if (pci_bios_check_devices(busses))
-        return;
+        goto done;
dprintf(1, "=== PCI new allocation pass #2 ===\n");
-    pci_bios_map_devices(busses);
+    pci_bios_map_devices(busses, mem);
pci_bios_init_devices();
free(busses);
pci_enable_default_vga();
+
+done:
+    if (mem)
+        free(mem);
 }
-- 
MST


    