From: Yinghai Lu <yhlu.kernel@gmail.com>
Subject: [PATCH] x86: split e820 reserved entries record to late v4

Linus said we should register some entries in e820 later,
so could let BAR res register at first, or even pnp?

this one replace
| commit a2bd7274b47124d2fc4dfdb8c0591f545ba749dd
| Author: Yinghai Lu <yhlu.kernel@gmail.com>
| Date:   Mon Aug 25 00:56:08 2008 -0700
|
|    x86: fix HPET regression in 2.6.26 versus 2.6.25, check hpet against BAR, v3

v2: insert e820 reserve resources before pnp_system_init
v3: fix merging problem in tip/x86/core
    please drop the one in tip/x86/core use this one instead
v4: address Linus's review about comments and condition in _late()

Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>

---
 arch/x86/kernel/e820.c |   24 +++++++++++++++++++++++-
 arch/x86/pci/i386.c    |    3 +++
 include/asm-x86/e820.h |    1 +
 3 files changed, 27 insertions(+), 1 deletion(-)

Index: linux-2.6/arch/x86/kernel/e820.c
===================================================================
--- linux-2.6.orig/arch/x86/kernel/e820.c
+++ linux-2.6/arch/x86/kernel/e820.c
@@ -1271,6 +1271,7 @@ static inline const char *e820_type_to_s
 /*
  * Mark e820 reserved areas as busy for the resource manager.
  */
+static struct resource __initdata *e820_res;
 void __init e820_reserve_resources(void)
 {
 	int i;
@@ -1278,6 +1279,7 @@ void __init e820_reserve_resources(void)
 	u64 end;
 
 	res = alloc_bootmem_low(sizeof(struct resource) * e820.nr_map);
+	e820_res = res;
 	for (i = 0; i < e820.nr_map; i++) {
 		end = e820.map[i].addr + e820.map[i].size - 1;
 #ifndef CONFIG_RESOURCES_64BIT
@@ -1291,7 +1293,14 @@ void __init e820_reserve_resources(void)
 		res->end = end;
 
 		res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;
-		insert_resource(&iomem_resource, res);
+
+		/*
+		 * don't register the region that could be conflicted with
+		 * pci device BAR resource and insert them later in
+		 * pcibios_resource_survey()
+		 */
+		if (e820.map[i].type != E820_RESERVED || res->start < (1ULL<<20))
+			insert_resource(&iomem_resource, res);
 		res++;
 	}
 
@@ -1303,6 +1312,19 @@ void __init e820_reserve_resources(void)
 	}
 }
 
+void __init e820_reserve_resources_late(void)
+{
+	int i;
+	struct resource *res;
+
+	res = e820_res;
+	for (i = 0; i < e820.nr_map; i++) {
+		if (!res->parent && res->end)
+			insert_resource(&iomem_resource, res);
+		res++;
+	}
+}
+
 char *__init default_machine_specific_memory_setup(void)
 {
 	char *who = "BIOS-e820";
Index: linux-2.6/arch/x86/pci/i386.c
===================================================================
--- linux-2.6.orig/arch/x86/pci/i386.c
+++ linux-2.6/arch/x86/pci/i386.c
@@ -33,6 +33,7 @@
 #include <linux/bootmem.h>
 
 #include <asm/pat.h>
+#include <asm/e820.h>
 
 #include "pci.h"
 
@@ -230,6 +231,8 @@ void __init pcibios_resource_survey(void
 	pcibios_allocate_bus_resources(&pci_root_buses);
 	pcibios_allocate_resources(0);
 	pcibios_allocate_resources(1);
+
+	e820_reserve_resources_late();
 }
 
 /**
Index: linux-2.6/include/asm-x86/e820.h
===================================================================
--- linux-2.6.orig/include/asm-x86/e820.h
+++ linux-2.6/include/asm-x86/e820.h
@@ -122,6 +122,7 @@ extern void e820_register_active_regions
 extern u64 e820_hole_size(u64 start, u64 end);
 extern void finish_e820_parsing(void);
 extern void e820_reserve_resources(void);
+extern void e820_reserve_resources_late(void);
 extern void setup_memory_map(void);
 extern char *default_machine_specific_memory_setup(void);
 extern char *machine_specific_memory_setup(void);