+++ /dev/null
-/*
- * 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 <asm/e820.h>
-#include <asm/io.h>
-#include <asm/iommu.h>
-#include <asm/pci-direct.h>
-#include <asm/dma.h>
-#include <asm/k8.h>
-
-int iommu_aperture;
-int iommu_aperture_disabled __initdata = 0;
-int iommu_aperture_allowed __initdata = 0;
-
-int fallback_aper_order __initdata = 1; /* 64MB */
-int fallback_aper_force __initdata = 0;
-
-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;
-
- if (fallback_aper_order > 7)
- fallback_aper_order = 7;
- aper_size = (32 * 1024 * 1024) << fallback_aper_order;
-
- /*
- * Aperture has to be naturally aligned. This means an 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.
- */
- p = __alloc_bootmem_nopanic(aper_size, aper_size, 0);
- if (!p || __pa(p)+aper_size > 0xffffffff) {
- printk("Cannot allocate aperture memory hole (%p,%uK)\n",
- p, aper_size>>10);
- if (p)
- free_bootmem(__pa(p), aper_size);
- return 0;
- }
- printk("Mapping aperture over %d KB of RAM @ %lx\n",
- aper_size >> 10, __pa(p));
- insert_aperture_resource((u32)__pa(p), aper_size);
- return (u32)__pa(p);
-}
-
-static int __init aperture_valid(u64 aper_base, u32 aper_size)
-{
- if (!aper_base)
- return 0;
- if (aper_size < 64*1024*1024) {
- printk("Aperture too small (%d MB)\n", aper_size>>20);
- return 0;
- }
- if (aper_base + aper_size > 0x100000000UL) {
- printk("Aperture beyond 4GB. Ignoring.\n");
- return 0;
- }
- if (e820_any_mapped(aper_base, aper_base + aper_size, E820_RAM)) {
- printk("Aperture pointing to e820 RAM. Ignoring.\n");
- return 0;
- }
- return 1;
-}
-
-/* Find a PCI capability */
-static __u32 __init find_cap(int num, int slot, int func, int cap)
-{
- u8 pos;
- int bytes;
- 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;
-
- printk("AGP bridge at %02x:%02x:%02x\n", num, slot, func);
- apsizereg = read_pci_config_16(num,slot,func, cap + 0x14);
- if (apsizereg == 0xffffffff) {
- printk("APSIZE in AGP bridge unreadable\n");
- return 0;
- }
-
- 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);
-
- printk("Aperture from AGP @ %Lx size %u MB (APSIZE %x)\n",
- aper, 32 << *order, apsizereg);
-
- if (!aperture_valid(aper, (32*1024*1024) << *order))
- 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("No AGP bridge found\n");
- return 0;
-}
-
-void __init iommu_hole_init(void)
-{
- int fix, num;
- u32 aper_size, aper_alloc = 0, aper_order = 0, last_aper_order = 0;
- u64 aper_base, last_aper_base = 0;
- int valid_agp = 0;
-
- if (iommu_aperture_disabled || !fix_aperture || !early_pci_allowed())
- return;
-
- printk(KERN_INFO "Checking aperture...\n");
-
- fix = 0;
- for (num = 24; num < 32; num++) {
- if (!early_is_k8_nb(read_pci_config(0, num, 3, 0x00)))
- continue;
-
- iommu_detected = 1;
- 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("CPU %d: aperture @ %Lx size %u MB\n", num-24,
- aper_base, aper_size>>20);
-
- if (!aperture_valid(aper_base, aper_size)) {
- 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 = search_agp_bridge(&aper_order, &valid_agp);
-
- 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("Your BIOS doesn't leave a aperture memory hole\n");
- printk("Please enable the IOMMU option in the BIOS setup\n");
- printk("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);
- }
-}
git.openpandora.org / pandora-kernel.git / blobdiff