x86: checking aperture size order
some systems are using 32M for gart and agp when memory is less than 4G.
Kernel will reject and try to allcate another 64M that is not needed,
and we will waste 64M of perfectly good RAM.
this patch adds a workaround by checking aper_base/order between NB and
agp bridge. If they are the same, and memory size is less than 4G, it
will allow it.
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
diff --git a/arch/x86/kernel/aperture_64.c b/arch/x86/kernel/aperture_64.c
index 2e93b31..8c325b7f 100644
--- a/arch/x86/kernel/aperture_64.c
+++ b/arch/x86/kernel/aperture_64.c
@@ -83,7 +83,7 @@
return (u32)__pa(p);
}
-static int __init aperture_valid(u64 aper_base, u32 aper_size)
+static int __init aperture_valid(u64 aper_base, u32 aper_size, u32 min_size)
{
if (!aper_base)
return 0;
@@ -96,8 +96,9 @@
printk(KERN_ERR "Aperture pointing to e820 RAM. Ignoring.\n");
return 0;
}
- if (aper_size < 64*1024*1024) {
- printk(KERN_ERR "Aperture too small (%d MB)\n", aper_size>>20);
+ if (aper_size < min_size) {
+ printk(KERN_ERR "Aperture too small (%d MB) than (%d MB)\n",
+ aper_size>>20, min_size>>20);
return 0;
}
@@ -167,7 +168,9 @@
* On some sick chips, APSIZE is 0. It means it wants 4G
* so let double check that order, and lets trust AMD NB settings:
*/
- if (aper + (32UL<<(20 + *order)) > 0x100000000UL) {
+ printk(KERN_INFO "Aperture from AGP @ %Lx old size %u MB\n",
+ aper, 32 << old_order);
+ if (aper + (32ULL<<(20 + *order)) > 0x100000000ULL) {
printk(KERN_INFO "Aperture size %u MB (APSIZE %x) is not right, using settings from NB\n",
32 << *order, apsizereg);
*order = old_order;
@@ -176,7 +179,7 @@
printk(KERN_INFO "Aperture from AGP @ %Lx size %u MB (APSIZE %x)\n",
aper, 32 << *order, apsizereg);
- if (!aperture_valid(aper, (32*1024*1024) << *order))
+ if (!aperture_valid(aper, (32*1024*1024) << *order, 32<<20))
return 0;
return (u32)aper;
}
@@ -302,8 +305,8 @@
fix = 1;
if (gart_fix_e820 && !fix && aper_enabled) {
- if (e820_any_mapped(aper_base, aper_base + aper_size,
- E820_RAM)) {
+ if (!e820_all_mapped(aper_base, aper_base + aper_size,
+ E820_RESERVED)) {
/* reserved it, so we can resuse it in second kernel */
printk(KERN_INFO "update e820 for GART\n");
add_memory_region(aper_base, aper_size, E820_RESERVED);
@@ -324,8 +327,11 @@
}
+static int __initdata printed_gart_size_msg;
+
void __init gart_iommu_hole_init(void)
{
+ u32 agp_aper_base = 0, agp_aper_order = 0;
u32 aper_size, aper_alloc = 0, aper_order = 0, last_aper_order = 0;
u64 aper_base, last_aper_base = 0;
int fix, num, valid_agp = 0;
@@ -337,6 +343,9 @@
printk(KERN_INFO "Checking aperture...\n");
+ if (!fallback_aper_force)
+ agp_aper_base = search_agp_bridge(&agp_aper_order, &valid_agp);
+
fix = 0;
node = 0;
for (num = 24; num < 32; num++) {
@@ -355,9 +364,21 @@
node, aper_base, aper_size >> 20);
node++;
- if (!aperture_valid(aper_base, aper_size)) {
- fix = 1;
- break;
+ if (!aperture_valid(aper_base, aper_size, 64<<20)) {
+ if (valid_agp && agp_aper_base &&
+ agp_aper_base == aper_base &&
+ agp_aper_order == aper_order) {
+ /* the same between two setting from NB and agp */
+ if (!no_iommu && end_pfn > MAX_DMA32_PFN && !printed_gart_size_msg) {
+ printk(KERN_ERR "you are using iommu with agp, but GART size is less than 64M\n");
+ printk(KERN_ERR "please increase GART size in your BIOS setup\n");
+ printk(KERN_ERR "if BIOS doesn't have that option, contact your HW vendor!\n");
+ printed_gart_size_msg = 1;
+ }
+ } else {
+ fix = 1;
+ break;
+ }
}
if ((last_aper_order && aper_order != last_aper_order) ||
@@ -378,8 +399,10 @@
return;
}
- if (!fallback_aper_force)
- aper_alloc = search_agp_bridge(&aper_order, &valid_agp);
+ if (!fallback_aper_force) {
+ aper_alloc = agp_aper_base;
+ aper_order = agp_aper_order;
+ }
if (aper_alloc) {
/* Got the aperture from the AGP bridge */