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-rw-r--r--arch/x86/kernel/aperture_64.c562
1 files changed, 562 insertions, 0 deletions
diff --git a/arch/x86/kernel/aperture_64.c b/arch/x86/kernel/aperture_64.c
new file mode 100644
index 000000000..4feaa670d
--- /dev/null
+++ b/arch/x86/kernel/aperture_64.c
@@ -0,0 +1,562 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Firmware replacement code.
+ *
+ * Work around broken BIOSes that don't set an aperture, only set the
+ * aperture in the AGP bridge, or set too small aperture.
+ *
+ * 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.
+ */
+#define pr_fmt(fmt) "AGP: " fmt
+
+#include <linux/kernel.h>
+#include <linux/kcore.h>
+#include <linux/types.h>
+#include <linux/init.h>
+#include <linux/memblock.h>
+#include <linux/mmzone.h>
+#include <linux/pci_ids.h>
+#include <linux/pci.h>
+#include <linux/bitops.h>
+#include <linux/suspend.h>
+#include <asm/e820/api.h>
+#include <asm/io.h>
+#include <asm/iommu.h>
+#include <asm/gart.h>
+#include <asm/pci-direct.h>
+#include <asm/dma.h>
+#include <asm/amd_nb.h>
+#include <asm/x86_init.h>
+#include <linux/crash_dump.h>
+
+/*
+ * Using 512M as goal, in case kexec will load kernel_big
+ * that will do the on-position decompress, and could overlap with
+ * the gart aperture that is used.
+ * Sequence:
+ * kernel_small
+ * ==> kexec (with kdump trigger path or gart still enabled)
+ * ==> kernel_small (gart area become e820_reserved)
+ * ==> kexec (with kdump trigger path or gart still enabled)
+ * ==> 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.
+ */
+#define GART_MIN_ADDR (512ULL << 20)
+#define GART_MAX_ADDR (1ULL << 32)
+
+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;
+
+#if defined(CONFIG_PROC_VMCORE) || defined(CONFIG_PROC_KCORE)
+/*
+ * If the first kernel maps the aperture over e820 RAM, the kdump kernel will
+ * use the same range because it will remain configured in the northbridge.
+ * Trying to dump this area via /proc/vmcore may crash the machine, so exclude
+ * it from vmcore.
+ */
+static unsigned long aperture_pfn_start, aperture_page_count;
+
+static int gart_mem_pfn_is_ram(unsigned long pfn)
+{
+ return likely((pfn < aperture_pfn_start) ||
+ (pfn >= aperture_pfn_start + aperture_page_count));
+}
+
+#ifdef CONFIG_PROC_VMCORE
+static bool gart_oldmem_pfn_is_ram(struct vmcore_cb *cb, unsigned long pfn)
+{
+ return !!gart_mem_pfn_is_ram(pfn);
+}
+
+static struct vmcore_cb gart_vmcore_cb = {
+ .pfn_is_ram = gart_oldmem_pfn_is_ram,
+};
+#endif
+
+static void __init exclude_from_core(u64 aper_base, u32 aper_order)
+{
+ aperture_pfn_start = aper_base >> PAGE_SHIFT;
+ aperture_page_count = (32 * 1024 * 1024) << aper_order >> PAGE_SHIFT;
+#ifdef CONFIG_PROC_VMCORE
+ register_vmcore_cb(&gart_vmcore_cb);
+#endif
+#ifdef CONFIG_PROC_KCORE
+ WARN_ON(register_mem_pfn_is_ram(&gart_mem_pfn_is_ram));
+#endif
+}
+#else
+static void exclude_from_core(u64 aper_base, u32 aper_order)
+{
+}
+#endif
+
+/* This code runs before the PCI subsystem is initialized, so just
+ access the northbridge directly. */
+
+static u32 __init allocate_aperture(void)
+{
+ u32 aper_size;
+ unsigned long addr;
+
+ /* 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.
+ */
+ addr = memblock_phys_alloc_range(aper_size, aper_size,
+ GART_MIN_ADDR, GART_MAX_ADDR);
+ if (!addr) {
+ pr_err("Cannot allocate aperture memory hole [mem %#010lx-%#010lx] (%uKB)\n",
+ addr, addr + aper_size - 1, aper_size >> 10);
+ return 0;
+ }
+ pr_info("Mapping aperture over RAM [mem %#010lx-%#010lx] (%uKB)\n",
+ addr, addr + aper_size - 1, aper_size >> 10);
+ register_nosave_region(addr >> PAGE_SHIFT,
+ (addr+aper_size) >> PAGE_SHIFT);
+
+ return (u32)addr;
+}
+
+
+/* Find a PCI capability */
+static u32 __init find_cap(int bus, int slot, int func, int cap)
+{
+ int bytes;
+ u8 pos;
+
+ if (!(read_pci_config_16(bus, slot, func, PCI_STATUS) &
+ PCI_STATUS_CAP_LIST))
+ return 0;
+
+ pos = read_pci_config_byte(bus, slot, func, PCI_CAPABILITY_LIST);
+ for (bytes = 0; bytes < 48 && pos >= 0x40; bytes++) {
+ u8 id;
+
+ pos &= ~3;
+ id = read_pci_config_byte(bus, slot, func, pos+PCI_CAP_LIST_ID);
+ if (id == 0xff)
+ break;
+ if (id == cap)
+ return pos;
+ pos = read_pci_config_byte(bus, slot, func,
+ pos+PCI_CAP_LIST_NEXT);
+ }
+ return 0;
+}
+
+/* Read a standard AGPv3 bridge header */
+static u32 __init read_agp(int bus, int slot, int func, int cap, u32 *order)
+{
+ u32 apsize;
+ u32 apsizereg;
+ int nbits;
+ u32 aper_low, aper_hi;
+ u64 aper;
+ u32 old_order;
+
+ pr_info("pci 0000:%02x:%02x:%02x: AGP bridge\n", bus, slot, func);
+ apsizereg = read_pci_config_16(bus, slot, func, cap + 0x14);
+ if (apsizereg == 0xffffffff) {
+ pr_err("pci 0000:%02x:%02x.%d: APSIZE unreadable\n",
+ bus, slot, func);
+ 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(bus, slot, func, 0x10);
+ aper_hi = read_pci_config(bus, 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:
+ */
+ pr_info("pci 0000:%02x:%02x.%d: AGP aperture [bus addr %#010Lx-%#010Lx] (old size %uMB)\n",
+ bus, slot, func, aper, aper + (32ULL << (old_order + 20)) - 1,
+ 32 << old_order);
+ if (aper + (32ULL<<(20 + *order)) > 0x100000000ULL) {
+ pr_info("pci 0000:%02x:%02x.%d: AGP aperture size %uMB (APSIZE %#x) is not right, using settings from NB\n",
+ bus, slot, func, 32 << *order, apsizereg);
+ *order = old_order;
+ }
+
+ pr_info("pci 0000:%02x:%02x.%d: AGP aperture [bus addr %#010Lx-%#010Lx] (%uMB, APSIZE %#x)\n",
+ bus, slot, func, aper, aper + (32ULL << (*order + 20)) - 1,
+ 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 AMD 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 bus, slot, func;
+
+ /* Poor man's PCI discovery */
+ for (bus = 0; bus < 256; bus++) {
+ for (slot = 0; slot < 32; slot++) {
+ for (func = 0; func < 8; func++) {
+ u32 class, cap;
+ u8 type;
+ class = read_pci_config(bus, 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(bus, slot, func,
+ PCI_CAP_ID_AGP);
+ if (!cap)
+ break;
+ *valid_agp = 1;
+ return read_agp(bus, slot, func, cap,
+ order);
+ }
+
+ /* No multi-function device? */
+ type = read_pci_config_byte(bus, slot, func,
+ PCI_HEADER_TYPE);
+ if (!(type & 0x80))
+ break;
+ }
+ }
+ }
+ pr_info("No AGP bridge found\n");
+
+ return 0;
+}
+
+static bool gart_fix_e820 __initdata = true;
+
+static int __init parse_gart_mem(char *p)
+{
+ return kstrtobool(p, &gart_fix_e820);
+}
+early_param("gart_fix_e820", parse_gart_mem);
+
+/*
+ * With kexec/kdump, if the first kernel doesn't shut down the GART and the
+ * second kernel allocates a different GART region, there might be two
+ * overlapping GART regions present:
+ *
+ * - the first still used by the GART initialized in the first kernel.
+ * - (sub-)set of it used as normal RAM by the second kernel.
+ *
+ * which leads to memory corruptions and a kernel panic eventually.
+ *
+ * This can also happen if the BIOS has forgotten to mark the GART region
+ * as reserved.
+ *
+ * Try to update the e820 map to mark that new region as reserved.
+ */
+void __init early_gart_iommu_check(void)
+{
+ u32 agp_aper_order = 0;
+ int i, fix, slot, valid_agp = 0;
+ 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, last_valid = 0;
+
+ if (!amd_gart_present())
+ return;
+
+ if (!early_pci_allowed())
+ return;
+
+ /* This is mostly duplicate of iommu_hole_init */
+ search_agp_bridge(&agp_aper_order, &valid_agp);
+
+ fix = 0;
+ for (i = 0; amd_nb_bus_dev_ranges[i].dev_limit; i++) {
+ int bus;
+ int dev_base, dev_limit;
+
+ bus = amd_nb_bus_dev_ranges[i].bus;
+ dev_base = amd_nb_bus_dev_ranges[i].dev_base;
+ dev_limit = amd_nb_bus_dev_ranges[i].dev_limit;
+
+ for (slot = dev_base; slot < dev_limit; slot++) {
+ if (!early_is_amd_nb(read_pci_config(bus, slot, 3, 0x00)))
+ continue;
+
+ ctl = read_pci_config(bus, slot, 3, AMD64_GARTAPERTURECTL);
+ aper_enabled = ctl & GARTEN;
+ aper_order = (ctl >> 1) & 7;
+ aper_size = (32 * 1024 * 1024) << aper_order;
+ aper_base = read_pci_config(bus, slot, 3, AMD64_GARTAPERTUREBASE) & 0x7fff;
+ aper_base <<= 25;
+
+ if (last_valid) {
+ if ((aper_order != last_aper_order) ||
+ (aper_base != last_aper_base) ||
+ (aper_enabled != last_aper_enabled)) {
+ fix = 1;
+ break;
+ }
+ }
+
+ last_aper_order = aper_order;
+ last_aper_base = aper_base;
+ last_aper_enabled = aper_enabled;
+ last_valid = 1;
+ }
+ }
+
+ 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__mapped_any(aper_base, aper_base + aper_size,
+ E820_TYPE_RAM)) {
+ /* reserve it, so we can reuse it in second kernel */
+ pr_info("e820: reserve [mem %#010Lx-%#010Lx] for GART\n",
+ aper_base, aper_base + aper_size - 1);
+ e820__range_add(aper_base, aper_size, E820_TYPE_RESERVED);
+ e820__update_table_print();
+ }
+ }
+
+ if (valid_agp)
+ return;
+
+ /* disable them all at first */
+ for (i = 0; i < amd_nb_bus_dev_ranges[i].dev_limit; i++) {
+ int bus;
+ int dev_base, dev_limit;
+
+ bus = amd_nb_bus_dev_ranges[i].bus;
+ dev_base = amd_nb_bus_dev_ranges[i].dev_base;
+ dev_limit = amd_nb_bus_dev_ranges[i].dev_limit;
+
+ for (slot = dev_base; slot < dev_limit; slot++) {
+ if (!early_is_amd_nb(read_pci_config(bus, slot, 3, 0x00)))
+ continue;
+
+ ctl = read_pci_config(bus, slot, 3, AMD64_GARTAPERTURECTL);
+ ctl &= ~GARTEN;
+ write_pci_config(bus, slot, 3, AMD64_GARTAPERTURECTL, 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, slot, valid_agp = 0;
+ int i, node;
+
+ if (!amd_gart_present())
+ return;
+
+ if (gart_iommu_aperture_disabled || !fix_aperture ||
+ !early_pci_allowed())
+ return;
+
+ pr_info("Checking aperture...\n");
+
+ if (!fallback_aper_force)
+ agp_aper_base = search_agp_bridge(&agp_aper_order, &valid_agp);
+
+ fix = 0;
+ node = 0;
+ for (i = 0; i < amd_nb_bus_dev_ranges[i].dev_limit; i++) {
+ int bus;
+ int dev_base, dev_limit;
+ u32 ctl;
+
+ bus = amd_nb_bus_dev_ranges[i].bus;
+ dev_base = amd_nb_bus_dev_ranges[i].dev_base;
+ dev_limit = amd_nb_bus_dev_ranges[i].dev_limit;
+
+ for (slot = dev_base; slot < dev_limit; slot++) {
+ if (!early_is_amd_nb(read_pci_config(bus, slot, 3, 0x00)))
+ continue;
+
+ iommu_detected = 1;
+ gart_iommu_aperture = 1;
+ x86_init.iommu.iommu_init = gart_iommu_init;
+
+ ctl = read_pci_config(bus, slot, 3,
+ AMD64_GARTAPERTURECTL);
+
+ /*
+ * Before we do anything else disable the GART. It may
+ * still be enabled if we boot into a crash-kernel here.
+ * Reconfiguring the GART while it is enabled could have
+ * unknown side-effects.
+ */
+ ctl &= ~GARTEN;
+ write_pci_config(bus, slot, 3, AMD64_GARTAPERTURECTL, ctl);
+
+ aper_order = (ctl >> 1) & 7;
+ aper_size = (32 * 1024 * 1024) << aper_order;
+ aper_base = read_pci_config(bus, slot, 3, AMD64_GARTAPERTUREBASE) & 0x7fff;
+ aper_base <<= 25;
+
+ pr_info("Node %d: aperture [bus addr %#010Lx-%#010Lx] (%uMB)\n",
+ node, aper_base, aper_base + aper_size - 1,
+ 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 &&
+ max_pfn > MAX_DMA32_PFN &&
+ !printed_gart_size_msg) {
+ pr_err("you are using iommu with agp, but GART size is less than 64MB\n");
+ pr_err("please increase GART size in your BIOS setup\n");
+ pr_err("if BIOS doesn't have that option, contact your HW vendor!\n");
+ printed_gart_size_msg = 1;
+ }
+ } else {
+ fix = 1;
+ goto out;
+ }
+ }
+
+ if ((last_aper_order && aper_order != last_aper_order) ||
+ (last_aper_base && aper_base != last_aper_base)) {
+ fix = 1;
+ goto out;
+ }
+ last_aper_order = aper_order;
+ last_aper_base = aper_base;
+ }
+ }
+
+out:
+ if (!fix && !fallback_aper_force) {
+ if (last_aper_base) {
+ /*
+ * If this is the kdump kernel, the first kernel
+ * may have allocated the range over its e820 RAM
+ * and fixed up the northbridge
+ */
+ exclude_from_core(last_aper_base, last_aper_order);
+ }
+ 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 ((!no_iommu && max_pfn > MAX_DMA32_PFN) ||
+ force_iommu ||
+ valid_agp ||
+ fallback_aper_force) {
+ pr_info("Your BIOS doesn't leave an aperture memory hole\n");
+ pr_info("Please enable the IOMMU option in the BIOS setup\n");
+ pr_info("This costs you %dMB 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;
+ }
+
+ /*
+ * If this is the kdump kernel _and_ the first kernel did not
+ * configure the aperture in the northbridge, this range may
+ * overlap with the first kernel's memory. We can't access the
+ * range through vmcore even though it should be part of the dump.
+ */
+ exclude_from_core(aper_alloc, aper_order);
+
+ /* Fix up the north bridges */
+ for (i = 0; i < amd_nb_bus_dev_ranges[i].dev_limit; i++) {
+ int bus, dev_base, dev_limit;
+
+ /*
+ * Don't enable translation yet but enable GART IO and CPU
+ * accesses and set DISTLBWALKPRB since GART table memory is UC.
+ */
+ u32 ctl = aper_order << 1;
+
+ bus = amd_nb_bus_dev_ranges[i].bus;
+ dev_base = amd_nb_bus_dev_ranges[i].dev_base;
+ dev_limit = amd_nb_bus_dev_ranges[i].dev_limit;
+ for (slot = dev_base; slot < dev_limit; slot++) {
+ if (!early_is_amd_nb(read_pci_config(bus, slot, 3, 0x00)))
+ continue;
+
+ write_pci_config(bus, slot, 3, AMD64_GARTAPERTURECTL, ctl);
+ write_pci_config(bus, slot, 3, AMD64_GARTAPERTUREBASE, aper_alloc >> 25);
+ }
+ }
+
+ set_up_gart_resume(aper_order, aper_alloc);
+}
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