alistair23-linux/arch/x86/kernel/aperture_64.c
Yinghai Lu 7677b2ef6c x86_64: allocate gart aperture from 512M
because we try to reserve dma32 early, so we have chance to get aperture
from 64M.

with some sequence aperture allocated from RAM, could become E820_RESERVED.

and then if doing a kexec with a big kernel that uncompressed size is above
64M we could have a range conflict with still using gart.

So allocate gart aperture from 512M instead.

Also change the fallback_aper_order to 5, because we don't have chance to get
2G or 4G aperture.

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>
2008-05-12 21:28:10 +02:00

468 lines
12 KiB
C

/*
* Firmware replacement code.
*
* Work around broken BIOSes that don't set an aperture or only set the
* aperture in the AGP bridge.
* If all fails map the aperture over some low memory. This is cheaper than
* doing bounce buffering. The memory is lost. This is done at early boot
* because only the bootmem allocator can allocate 32+MB.
*
* Copyright 2002 Andi Kleen, SuSE Labs.
*/
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/init.h>
#include <linux/bootmem.h>
#include <linux/mmzone.h>
#include <linux/pci_ids.h>
#include <linux/pci.h>
#include <linux/bitops.h>
#include <linux/ioport.h>
#include <linux/suspend.h>
#include <asm/e820.h>
#include <asm/io.h>
#include <asm/gart.h>
#include <asm/pci-direct.h>
#include <asm/dma.h>
#include <asm/k8.h>
int gart_iommu_aperture;
int gart_iommu_aperture_disabled __initdata;
int gart_iommu_aperture_allowed __initdata;
int fallback_aper_order __initdata = 1; /* 64MB */
int fallback_aper_force __initdata;
int fix_aperture __initdata = 1;
static struct resource gart_resource = {
.name = "GART",
.flags = IORESOURCE_MEM,
};
static void __init insert_aperture_resource(u32 aper_base, u32 aper_size)
{
gart_resource.start = aper_base;
gart_resource.end = aper_base + aper_size - 1;
insert_resource(&iomem_resource, &gart_resource);
}
/* This code runs before the PCI subsystem is initialized, so just
access the northbridge directly. */
static u32 __init allocate_aperture(void)
{
u32 aper_size;
void *p;
/* aper_size should <= 1G */
if (fallback_aper_order > 5)
fallback_aper_order = 5;
aper_size = (32 * 1024 * 1024) << fallback_aper_order;
/*
* Aperture has to be naturally aligned. This means a 2GB aperture
* won't have much chance of finding a place in the lower 4GB of
* memory. Unfortunately we cannot move it up because that would
* make the IOMMU useless.
*/
/*
* using 512M as goal, in case kexec will load kernel_big
* that will do the on position decompress, and could overlap with
* that positon with gart that is used.
* sequende:
* kernel_small
* ==> kexec (with kdump trigger path or previous doesn't shutdown gart)
* ==> kernel_small(gart area become e820_reserved)
* ==> kexec (with kdump trigger path or previous doesn't shutdown gart)
* ==> kerne_big (uncompressed size will be big than 64M or 128M)
* so don't use 512M below as gart iommu, leave the space for kernel
* code for safe
*/
p = __alloc_bootmem_nopanic(aper_size, aper_size, 512ULL<<20);
if (!p || __pa(p)+aper_size > 0xffffffff) {
printk(KERN_ERR
"Cannot allocate aperture memory hole (%p,%uK)\n",
p, aper_size>>10);
if (p)
free_bootmem(__pa(p), aper_size);
return 0;
}
printk(KERN_INFO "Mapping aperture over %d KB of RAM @ %lx\n",
aper_size >> 10, __pa(p));
insert_aperture_resource((u32)__pa(p), aper_size);
register_nosave_region((u32)__pa(p) >> PAGE_SHIFT,
(u32)__pa(p+aper_size) >> PAGE_SHIFT);
return (u32)__pa(p);
}
static int __init aperture_valid(u64 aper_base, u32 aper_size, u32 min_size)
{
if (!aper_base)
return 0;
if (aper_base + aper_size > 0x100000000UL) {
printk(KERN_ERR "Aperture beyond 4GB. Ignoring.\n");
return 0;
}
if (e820_any_mapped(aper_base, aper_base + aper_size, E820_RAM)) {
printk(KERN_ERR "Aperture pointing to e820 RAM. Ignoring.\n");
return 0;
}
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;
}
return 1;
}
/* Find a PCI capability */
static __u32 __init find_cap(int num, int slot, int func, int cap)
{
int bytes;
u8 pos;
if (!(read_pci_config_16(num, slot, func, PCI_STATUS) &
PCI_STATUS_CAP_LIST))
return 0;
pos = read_pci_config_byte(num, slot, func, PCI_CAPABILITY_LIST);
for (bytes = 0; bytes < 48 && pos >= 0x40; bytes++) {
u8 id;
pos &= ~3;
id = read_pci_config_byte(num, slot, func, pos+PCI_CAP_LIST_ID);
if (id == 0xff)
break;
if (id == cap)
return pos;
pos = read_pci_config_byte(num, slot, func,
pos+PCI_CAP_LIST_NEXT);
}
return 0;
}
/* Read a standard AGPv3 bridge header */
static __u32 __init read_agp(int num, int slot, int func, int cap, u32 *order)
{
u32 apsize;
u32 apsizereg;
int nbits;
u32 aper_low, aper_hi;
u64 aper;
u32 old_order;
printk(KERN_INFO "AGP bridge at %02x:%02x:%02x\n", num, slot, func);
apsizereg = read_pci_config_16(num, slot, func, cap + 0x14);
if (apsizereg == 0xffffffff) {
printk(KERN_ERR "APSIZE in AGP bridge unreadable\n");
return 0;
}
/* old_order could be the value from NB gart setting */
old_order = *order;
apsize = apsizereg & 0xfff;
/* Some BIOS use weird encodings not in the AGPv3 table. */
if (apsize & 0xff)
apsize |= 0xf00;
nbits = hweight16(apsize);
*order = 7 - nbits;
if ((int)*order < 0) /* < 32MB */
*order = 0;
aper_low = read_pci_config(num, slot, func, 0x10);
aper_hi = read_pci_config(num, slot, func, 0x14);
aper = (aper_low & ~((1<<22)-1)) | ((u64)aper_hi << 32);
/*
* On some sick chips, APSIZE is 0. It means it wants 4G
* so let double check that order, and lets trust AMD NB settings:
*/
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;
}
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, 32<<20))
return 0;
return (u32)aper;
}
/*
* Look for an AGP bridge. Windows only expects the aperture in the
* AGP bridge and some BIOS forget to initialize the Northbridge too.
* Work around this here.
*
* Do an PCI bus scan by hand because we're running before the PCI
* subsystem.
*
* All K8 AGP bridges are AGPv3 compliant, so we can do this scan
* generically. It's probably overkill to always scan all slots because
* the AGP bridges should be always an own bus on the HT hierarchy,
* but do it here for future safety.
*/
static __u32 __init search_agp_bridge(u32 *order, int *valid_agp)
{
int num, slot, func;
/* Poor man's PCI discovery */
for (num = 0; num < 256; num++) {
for (slot = 0; slot < 32; slot++) {
for (func = 0; func < 8; func++) {
u32 class, cap;
u8 type;
class = read_pci_config(num, slot, func,
PCI_CLASS_REVISION);
if (class == 0xffffffff)
break;
switch (class >> 16) {
case PCI_CLASS_BRIDGE_HOST:
case PCI_CLASS_BRIDGE_OTHER: /* needed? */
/* AGP bridge? */
cap = find_cap(num, slot, func,
PCI_CAP_ID_AGP);
if (!cap)
break;
*valid_agp = 1;
return read_agp(num, slot, func, cap,
order);
}
/* No multi-function device? */
type = read_pci_config_byte(num, slot, func,
PCI_HEADER_TYPE);
if (!(type & 0x80))
break;
}
}
}
printk(KERN_INFO "No AGP bridge found\n");
return 0;
}
static int gart_fix_e820 __initdata = 1;
static int __init parse_gart_mem(char *p)
{
if (!p)
return -EINVAL;
if (!strncmp(p, "off", 3))
gart_fix_e820 = 0;
else if (!strncmp(p, "on", 2))
gart_fix_e820 = 1;
return 0;
}
early_param("gart_fix_e820", parse_gart_mem);
void __init early_gart_iommu_check(void)
{
/*
* in case it is enabled before, esp for kexec/kdump,
* previous kernel already enable that. memset called
* by allocate_aperture/__alloc_bootmem_nopanic cause restart.
* or second kernel have different position for GART hole. and new
* kernel could use hole as RAM that is still used by GART set by
* first kernel
* or BIOS forget to put that in reserved.
* try to update e820 to make that region as reserved.
*/
int fix, num;
u32 ctl;
u32 aper_size = 0, aper_order = 0, last_aper_order = 0;
u64 aper_base = 0, last_aper_base = 0;
int aper_enabled = 0, last_aper_enabled = 0;
if (!early_pci_allowed())
return;
fix = 0;
for (num = 24; num < 32; num++) {
if (!early_is_k8_nb(read_pci_config(0, num, 3, 0x00)))
continue;
ctl = read_pci_config(0, num, 3, 0x90);
aper_enabled = ctl & 1;
aper_order = (ctl >> 1) & 7;
aper_size = (32 * 1024 * 1024) << aper_order;
aper_base = read_pci_config(0, num, 3, 0x94) & 0x7fff;
aper_base <<= 25;
if ((last_aper_order && aper_order != last_aper_order) ||
(last_aper_base && aper_base != last_aper_base) ||
(last_aper_enabled && aper_enabled != last_aper_enabled)) {
fix = 1;
break;
}
last_aper_order = aper_order;
last_aper_base = aper_base;
last_aper_enabled = aper_enabled;
}
if (!fix && !aper_enabled)
return;
if (!aper_base || !aper_size || aper_base + aper_size > 0x100000000UL)
fix = 1;
if (gart_fix_e820 && !fix && aper_enabled) {
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);
update_e820();
}
return;
}
/* different nodes have different setting, disable them all at first*/
for (num = 24; num < 32; num++) {
if (!early_is_k8_nb(read_pci_config(0, num, 3, 0x00)))
continue;
ctl = read_pci_config(0, num, 3, 0x90);
ctl &= ~1;
write_pci_config(0, num, 3, 0x90, ctl);
}
}
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;
int node;
if (gart_iommu_aperture_disabled || !fix_aperture ||
!early_pci_allowed())
return;
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++) {
if (!early_is_k8_nb(read_pci_config(0, num, 3, 0x00)))
continue;
iommu_detected = 1;
gart_iommu_aperture = 1;
aper_order = (read_pci_config(0, num, 3, 0x90) >> 1) & 7;
aper_size = (32 * 1024 * 1024) << aper_order;
aper_base = read_pci_config(0, num, 3, 0x94) & 0x7fff;
aper_base <<= 25;
printk(KERN_INFO "Node %d: aperture @ %Lx size %u MB\n",
node, aper_base, aper_size >> 20);
node++;
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) ||
(last_aper_base && aper_base != last_aper_base)) {
fix = 1;
break;
}
last_aper_order = aper_order;
last_aper_base = aper_base;
}
if (!fix && !fallback_aper_force) {
if (last_aper_base) {
unsigned long n = (32 * 1024 * 1024) << last_aper_order;
insert_aperture_resource((u32)last_aper_base, n);
}
return;
}
if (!fallback_aper_force) {
aper_alloc = agp_aper_base;
aper_order = agp_aper_order;
}
if (aper_alloc) {
/* Got the aperture from the AGP bridge */
} else if (swiotlb && !valid_agp) {
/* Do nothing */
} else if ((!no_iommu && end_pfn > MAX_DMA32_PFN) ||
force_iommu ||
valid_agp ||
fallback_aper_force) {
printk(KERN_ERR
"Your BIOS doesn't leave a aperture memory hole\n");
printk(KERN_ERR
"Please enable the IOMMU option in the BIOS setup\n");
printk(KERN_ERR
"This costs you %d MB of RAM\n",
32 << fallback_aper_order);
aper_order = fallback_aper_order;
aper_alloc = allocate_aperture();
if (!aper_alloc) {
/*
* Could disable AGP and IOMMU here, but it's
* probably not worth it. But the later users
* cannot deal with bad apertures and turning
* on the aperture over memory causes very
* strange problems, so it's better to panic
* early.
*/
panic("Not enough memory for aperture");
}
} else {
return;
}
/* Fix up the north bridges */
for (num = 24; num < 32; num++) {
if (!early_is_k8_nb(read_pci_config(0, num, 3, 0x00)))
continue;
/*
* Don't enable translation yet. That is done later.
* Assume this BIOS didn't initialise the GART so
* just overwrite all previous bits
*/
write_pci_config(0, num, 3, 0x90, aper_order<<1);
write_pci_config(0, num, 3, 0x94, aper_alloc>>25);
}
}