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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 01:02:30 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 01:02:30 +0000 |
commit | 76cb841cb886eef6b3bee341a2266c76578724ad (patch) | |
tree | f5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /arch/x86/kernel/aperture_64.c | |
parent | Initial commit. (diff) | |
download | linux-76cb841cb886eef6b3bee341a2266c76578724ad.tar.xz linux-76cb841cb886eef6b3bee341a2266c76578724ad.zip |
Adding upstream version 4.19.249.upstream/4.19.249
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/x86/kernel/aperture_64.c')
-rw-r--r-- | arch/x86/kernel/aperture_64.c | 551 |
1 files changed, 551 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..93426c5fc --- /dev/null +++ b/arch/x86/kernel/aperture_64.c @@ -0,0 +1,551 @@ +// 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 + * 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)); +} + +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 + WARN_ON(register_oldmem_pfn_is_ram(&gart_mem_pfn_is_ram)); +#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_find_in_range(GART_MIN_ADDR, GART_MAX_ADDR, + aper_size, aper_size); + if (!addr) { + pr_err("Cannot allocate aperture memory hole [mem %#010lx-%#010lx] (%uKB)\n", + addr, addr + aper_size - 1, aper_size >> 10); + return 0; + } + memblock_reserve(addr, aper_size); + 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); + +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. + */ + 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; + +int __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 -ENODEV; + + if (gart_iommu_aperture_disabled || !fix_aperture || + !early_pci_allowed()) + return -ENODEV; + + 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 1; + } + return 0; + } + + 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 0; + } + + /* + * 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); + + return 1; +} |