// SPDX-License-Identifier: GPL-2.0-or-later
/*
* PowerPC version
* Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
*
* Modifications by Paul Mackerras (PowerMac) (paulus@cs.anu.edu.au)
* and Cort Dougan (PReP) (cort@cs.nmt.edu)
* Copyright (C) 1996 Paul Mackerras
* PPC44x/36-bit changes by Matt Porter (mporter@mvista.com)
*
* Derived from "arch/i386/mm/init.c"
* Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds
*/
#include <linux/memblock.h>
#include <linux/highmem.h>
#include <linux/suspend.h>
#include <linux/dma-direct.h>
#include <asm/swiotlb.h>
#include <asm/machdep.h>
#include <asm/rtas.h>
#include <asm/kasan.h>
#include <asm/svm.h>
#include <asm/mmzone.h>
#include <asm/ftrace.h>
#include <asm/code-patching.h>
#include <asm/setup.h>
#include <mm/mmu_decl.h>
unsigned long long memory_limit;
unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)] __page_aligned_bss;
EXPORT_SYMBOL(empty_zero_page);
pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
unsigned long size, pgprot_t vma_prot)
{
if (ppc_md.phys_mem_access_prot)
return ppc_md.phys_mem_access_prot(file, pfn, size, vma_prot);
if (!page_is_ram(pfn))
vma_prot = pgprot_noncached(vma_prot);
return vma_prot;
}
EXPORT_SYMBOL(phys_mem_access_prot);
#ifdef CONFIG_MEMORY_HOTPLUG
static DEFINE_MUTEX(linear_mapping_mutex);
#ifdef CONFIG_NUMA
int memory_add_physaddr_to_nid(u64 start)
{
return hot_add_scn_to_nid(start);
}
EXPORT_SYMBOL_GPL(memory_add_physaddr_to_nid);
#endif
int __weak create_section_mapping(unsigned long start, unsigned long end,
int nid, pgprot_t prot)
{
return -ENODEV;
}
int __weak remove_section_mapping(unsigned long start, unsigned long end)
{
return -ENODEV;
}
int __ref arch_create_linear_mapping(int nid, u64 start, u64 size,
struct mhp_params *params)
{
int rc;
start = (unsigned long)__va(start);
mutex_lock(&linear_mapping_mutex);
rc = create_section_mapping(start, start + size, nid,
params->pgprot);
mutex_unlock(&linear_mapping_mutex);
if (rc) {
pr_warn("Unable to create linear mapping for 0x%llx..0x%llx: %d\n",
start, start + size, rc);
return -EFAULT;
}
return 0;
}
void __ref arch_remove_linear_mapping(u64 start, u64 size)
{
int ret;
/* Remove htab bolted mappings for this section of memory */
start = (unsigned long)__va(start);
mutex_lock(&linear_mapping_mutex);
ret = remove_section_mapping(start, start + size);
mutex_unlock(&linear_mapping_mutex);
if (ret)
pr_warn("Unable to remove linear mapping for 0x%llx..0x%llx: %d\n",
start, start + size, ret);
/* Ensure all vmalloc mappings are flushed in case they also
* hit that section of memory
*/
vm_unmap_aliases();
}
/*
* After memory hotplug the variables max_pfn, max_low_pfn and high_memory need
* updating.
*/
static void update_end_of_memory_vars(u64 start, u64 size)
{
unsigned long end_pfn = PFN_UP(start + size);
if (end_pfn > max_pfn) {
max_pfn = end_pfn;
max_low_pfn = end_pfn;
high_memory = (void *)__va(max_pfn * PAGE_SIZE - 1) + 1;
}
}
int __ref add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages,
struct mhp_params *params)
{
int ret;
ret = __add_pages(nid, start_pfn, nr_pages, params);
if (ret)
return ret;
/* update max_pfn, max_low_pfn and high_memory */
update_end_of_memory_vars(start_pfn << PAGE_SHIFT,
nr_pages << PAGE_SHIFT);
return ret;
}
int __ref arch_add_memory(int nid, u64 start, u64 size,
struct mhp_params *params)
{
unsigned long start_pfn = start >> PAGE_SHIFT;
unsigned long nr_pages = size >> PAGE_SHIFT;
int rc;
rc = arch_create_linear_mapping(nid, start, size, params);
if (rc)
return rc;
rc = add_pages(nid, start_pfn, nr_pages, params);
if (rc)
arch_remove_linear_mapping(start, size);
return rc;
}
void __ref arch_remove_memory(u64 start, u64 size, struct vmem_altmap *altmap)
{
unsigned long start_pfn = start >> PAGE_SHIFT;
unsigned long nr_pages = size >> PAGE_SHIFT;
__remove_pages(start_pfn, nr_pages, altmap);
arch_remove_linear_mapping(start, size);
}
#endif
#ifndef CONFIG_NUMA
void __init mem_topology_setup(void)
{
max_low_pfn = max_pfn = memblock_end_of_DRAM() >> PAGE_SHIFT;
min_low_pfn = MEMORY_START >> PAGE_SHIFT;
#ifdef CONFIG_HIGHMEM
max_low_pfn = lowmem_end_addr >> PAGE_SHIFT;
#endif
/* Place all memblock_regions in the same node and merge contiguous
* memblock_regions
*/
memblock_set_node(0, PHYS_ADDR_MAX, &memblock.memory, 0);
}
void __init initmem_init(void)
{
sparse_init();
}
/* mark pages that don't exist as nosave */
static int __init mark_nonram_nosave(void)
{
unsigned long spfn, epfn, prev = 0;
int i;
for_each_mem_pfn_range(i, MAX_NUMNODES, &spfn, &epfn, NULL) {
if (prev && prev < spfn)
register_nosave_region(prev, spfn);
prev = epfn;
}
return 0;
}
#else /* CONFIG_NUMA */
static int __init mark_nonram_nosave(void)
{
return 0;
}
#endif
/*
* Zones usage:
*
* We setup ZONE_DMA to be 31-bits on all platforms and ZONE_NORMAL to be
* everything else. GFP_DMA32 page allocations automatically fall back to
* ZONE_DMA.
*
* By using 31-bit unconditionally, we can exploit zone_dma_bits to inform the
* generic DMA mapping code. 32-bit only devices (if not handled by an IOMMU
* anyway) will take a first dip into ZONE_NORMAL and get otherwise served by
* ZONE_DMA.
*/
static unsigned long max_zone_pfns[MAX_NR_ZONES];
/*
* paging_init() sets up the page tables - in fact we've already done this.
*/
void __init paging_init(void)
{
unsigned long long total_ram = memblock_phys_mem_size();
phys_addr_t top_of_ram = memblock_end_of_DRAM();
#ifdef CONFIG_HIGHMEM
unsigned long v = __fix_to_virt(FIX_KMAP_END);
unsigned long end = __fix_to_virt(FIX_KMAP_BEGIN);
for (; v < end; v += PAGE_SIZE)
map_kernel_page(v, 0, __pgprot(0)); /* XXX gross */
map_kernel_page(PKMAP_BASE, 0, __pgprot(0)); /* XXX gross */
pkmap_page_table = virt_to_kpte(PKMAP_BASE);
#endif /* CONFIG_HIGHMEM */
printk(KERN_DEBUG "Top of RAM: 0x%llx, Total RAM: 0x%llx\n",
(unsigned long long)top_of_ram, total_ram);
printk(KERN_DEBUG "Memory hole size: %ldMB\n",
(long int)((top_of_ram - total_ram) >> 20));
/*
* Allow 30-bit DMA for very limited Broadcom wifi chips on many
* powerbooks.
*/
if (IS_ENABLED(CONFIG_PPC32))
zone_dma_bits = 30;
else
zone_dma_bits = 31;
#ifdef CONFIG_ZONE_DMA
max_zone_pfns[ZONE_DMA] = min(max_low_pfn,
1UL << (zone_dma_bits - PAGE_SHIFT));
#endif
max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
#ifdef CONFIG_HIGHMEM
max_zone_pfns[ZONE_HIGHMEM] = max_pfn;
#endif
free_area_init(max_zone_pfns);
mark_nonram_nosave();
}
void __init mem_init(void)
{
/*
* book3s is limited to 16 page sizes due to encoding this in
* a 4-bit field for slices.
*/
BUILD_BUG_ON(MMU_PAGE_COUNT > 16);
#ifdef CONFIG_SWIOTLB
/*
* Some platforms (e.g. 85xx) limit DMA-able memory way below
* 4G. We force memblock to bottom-up mode to ensure that the
* memory allocated in swiotlb_init() is DMA-able.
* As it's the last memblock allocation, no need to reset it
* back to to-down.
*/
memblock_set_bottom_up(true);
swiotlb_init(ppc_swiotlb_enable, ppc_swiotlb_flags);
#endif
high_memory = (void *) __va(max_low_pfn * PAGE_SIZE);
kasan_late_init();
memblock_free_all();
#ifdef CONFIG_HIGHMEM
{
unsigned long pfn, highmem_mapnr;
highmem_mapnr = lowmem_end_addr >> PAGE_SHIFT;
for (pfn = highmem_mapnr; pfn < max_mapnr; ++pfn) {
phys_addr_t paddr = (phys_addr_t)pfn << PAGE_SHIFT;
struct page *page = pfn_to_page(pfn);
if (memblock_is_memory(paddr) && !memblock_is_reserved(paddr))
free_highmem_page(page);
}
}
#endif /* CONFIG_HIGHMEM */
#if defined(CONFIG_PPC_E500) && !defined(CONFIG_SMP)
/*
* If smp is enabled, next_tlbcam_idx is initialized in the cpu up
* functions.... do it here for the non-smp case.
*/
per_cpu(next_tlbcam_idx, smp_processor_id()) =
(mfspr(SPRN_TLB1CFG) & TLBnCFG_N_ENTRY) - 1;
#endif
#ifdef CONFIG_PPC32
pr_info("Kernel virtual memory layout:\n");
#ifdef CONFIG_KASAN
pr_info(" * 0x%08lx..0x%08lx : kasan shadow mem\n",
KASAN_SHADOW_START, KASAN_SHADOW_END);
#endif
pr_info(" * 0x%08lx..0x%08lx : fixmap\n", FIXADDR_START, FIXADDR_TOP);
#ifdef CONFIG_HIGHMEM
pr_info(" * 0x%08lx..0x%08lx : highmem PTEs\n",
PKMAP_BASE, PKMAP_ADDR(LAST_PKMAP));
#endif /* CONFIG_HIGHMEM */
if (ioremap_bot != IOREMAP_TOP)
pr_info(" * 0x%08lx..0x%08lx : early ioremap\n",
ioremap_bot, IOREMAP_TOP);
pr_info(" * 0x%08lx..0x%08lx : vmalloc & ioremap\n",
VMALLOC_START, VMALLOC_END);
#ifdef MODULES_VADDR
pr_info(" * 0x%08lx..0x%08lx : modules\n",
MODULES_VADDR, MODULES_END);
#endif
#endif /* CONFIG_PPC32 */
}
void free_initmem(void)
{
ppc_md.progress = ppc_printk_progress;
mark_initmem_nx();
free_initmem_default(POISON_FREE_INITMEM);
ftrace_free_init_tramp();
}
/*
* System memory should not be in /proc/iomem but various tools expect it
* (eg kdump).
*/
static int __init add_system_ram_resources(void)
{
phys_addr_t start, end;
u64 i;
for_each_mem_range(i, &start, &end) {
struct resource *res;
res = kzalloc(sizeof(struct resource), GFP_KERNEL);
WARN_ON(!res);
if (res) {
res->name = "System RAM";
res->start = start;
/*
* In memblock, end points to the first byte after
* the range while in resourses, end points to the
* last byte in the range.
*/
res->end = end - 1;
res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
WARN_ON(request_resource(&iomem_resource, res) < 0);
}
}
return 0;
}
subsys_initcall(add_system_ram_resources);
#ifdef CONFIG_STRICT_DEVMEM
/*
* devmem_is_allowed(): check to see if /dev/mem access to a certain address
* is valid. The argument is a physical page number.
*
* Access has to be given to non-kernel-ram areas as well, these contain the
* PCI mmio resources as well as potential bios/acpi data regions.
*/
int devmem_is_allowed(unsigned long pfn)
{
if (page_is_rtas_user_buf(pfn))
return 1;
if (iomem_is_exclusive(PFN_PHYS(pfn)))
return 0;
if (!page_is_ram(pfn))
return 1;
return 0;
}
#endif /* CONFIG_STRICT_DEVMEM */
/*
* This is defined in kernel/resource.c but only powerpc needs to export it, for
* the EHEA driver. Drop this when drivers/net/ethernet/ibm/ehea is removed.
*/
EXPORT_SYMBOL_GPL(walk_system_ram_range);