#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/init.h>
+#include <linux/libfdt.h>
#include <linux/mman.h>
#include <linux/nodemask.h>
#include <linux/memblock.h>
#include <asm/cputype.h>
#include <asm/fixmap.h>
+#include <asm/kernel-pgtable.h>
#include <asm/sections.h>
#include <asm/setup.h>
#include <asm/sizes.h>
static void __init *early_alloc(unsigned long sz)
{
- void *ptr = __va(memblock_alloc(sz, sz));
- BUG_ON(!ptr);
+ phys_addr_t phys;
+ void *ptr;
+
+ phys = memblock_alloc(sz, sz);
+ BUG_ON(!phys);
+ ptr = __va(phys);
memset(ptr, 0, sz);
return ptr;
}
} while (pte++, addr += PAGE_SIZE, addr != end);
}
-void split_pud(pud_t *old_pud, pmd_t *pmd)
+static void split_pud(pud_t *old_pud, pmd_t *pmd)
{
unsigned long addr = pud_pfn(*old_pud) << PAGE_SHIFT;
pgprot_t prot = __pgprot(pud_val(*old_pud) ^ addr);
int i = 0;
do {
- set_pmd(pmd, __pmd(addr | prot));
+ set_pmd(pmd, __pmd(addr | pgprot_val(prot)));
addr += PMD_SIZE;
} while (pmd++, i++, i < PTRS_PER_PMD);
}
return ptr;
}
-static void __ref create_mapping(phys_addr_t phys, unsigned long virt,
+static void __init create_mapping(phys_addr_t phys, unsigned long virt,
phys_addr_t size, pgprot_t prot)
{
if (virt < VMALLOC_START) {
* for now. This will get more fine grained later once all memory
* is mapped
*/
- unsigned long kernel_x_start = round_down(__pa(_stext), SECTION_SIZE);
- unsigned long kernel_x_end = round_up(__pa(__init_end), SECTION_SIZE);
+ unsigned long kernel_x_start = round_down(__pa(_stext), SWAPPER_BLOCK_SIZE);
+ unsigned long kernel_x_end = round_up(__pa(__init_end), SWAPPER_BLOCK_SIZE);
if (end < kernel_x_start) {
create_mapping(start, __phys_to_virt(start),
* memory addressable from the initial direct kernel mapping.
*
* The initial direct kernel mapping, located at swapper_pg_dir, gives
- * us PUD_SIZE (4K pages) or PMD_SIZE (64K pages) memory starting from
- * PHYS_OFFSET (which must be aligned to 2MB as per
- * Documentation/arm64/booting.txt).
+ * us PUD_SIZE (with SECTION maps) or PMD_SIZE (without SECTION maps,
+ * memory starting from PHYS_OFFSET (which must be aligned to 2MB as
+ * per Documentation/arm64/booting.txt).
*/
- if (IS_ENABLED(CONFIG_ARM64_64K_PAGES))
- limit = PHYS_OFFSET + PMD_SIZE;
- else
- limit = PHYS_OFFSET + PUD_SIZE;
+ limit = PHYS_OFFSET + SWAPPER_INIT_MAP_SIZE;
memblock_set_current_limit(limit);
/* map all the memory banks */
if (start >= end)
break;
-#ifndef CONFIG_ARM64_64K_PAGES
- /*
- * For the first memory bank align the start address and
- * current memblock limit to prevent create_mapping() from
- * allocating pte page tables from unmapped memory.
- * When 64K pages are enabled, the pte page table for the
- * first PGDIR_SIZE is already present in swapper_pg_dir.
- */
- if (start < limit)
- start = ALIGN(start, PMD_SIZE);
- if (end < limit) {
- limit = end & PMD_MASK;
- memblock_set_current_limit(limit);
+ if (ARM64_SWAPPER_USES_SECTION_MAPS) {
+ /*
+ * For the first memory bank align the start address and
+ * current memblock limit to prevent create_mapping() from
+ * allocating pte page tables from unmapped memory. With
+ * the section maps, if the first block doesn't end on section
+ * size boundary, create_mapping() will try to allocate a pte
+ * page, which may be returned from an unmapped area.
+ * When section maps are not used, the pte page table for the
+ * current limit is already present in swapper_pg_dir.
+ */
+ if (start < limit)
+ start = ALIGN(start, SECTION_SIZE);
+ if (end < limit) {
+ limit = end & SECTION_MASK;
+ memblock_set_current_limit(limit);
+ }
}
-#endif
__map_memblock(start, end);
}
memblock_set_current_limit(MEMBLOCK_ALLOC_ANYWHERE);
}
-void __init fixup_executable(void)
+static void __init fixup_executable(void)
{
#ifdef CONFIG_DEBUG_RODATA
/* now that we are actually fully mapped, make the start/end more fine grained */
- if (!IS_ALIGNED((unsigned long)_stext, SECTION_SIZE)) {
+ if (!IS_ALIGNED((unsigned long)_stext, SWAPPER_BLOCK_SIZE)) {
unsigned long aligned_start = round_down(__pa(_stext),
- SECTION_SIZE);
+ SWAPPER_BLOCK_SIZE);
create_mapping(aligned_start, __phys_to_virt(aligned_start),
__pa(_stext) - aligned_start,
PAGE_KERNEL);
}
- if (!IS_ALIGNED((unsigned long)__init_end, SECTION_SIZE)) {
+ if (!IS_ALIGNED((unsigned long)__init_end, SWAPPER_BLOCK_SIZE)) {
unsigned long aligned_end = round_up(__pa(__init_end),
- SECTION_SIZE);
+ SWAPPER_BLOCK_SIZE);
create_mapping(__pa(__init_end), (unsigned long)__init_end,
aligned_end - __pa(__init_end),
PAGE_KERNEL);
{
create_mapping_late(__pa(_stext), (unsigned long)_stext,
(unsigned long)_etext - (unsigned long)_stext,
- PAGE_KERNEL_EXEC | PTE_RDONLY);
+ PAGE_KERNEL_ROX);
}
#endif
empty_zero_page = virt_to_page(zero_page);
+ /* Ensure the zero page is visible to the page table walker */
+ dsb(ishst);
+
/*
* TTBR0 is only used for the identity mapping at this stage. Make it
* point to zero page to avoid speculatively fetching new entries.
*/
cpu_set_reserved_ttbr0();
- flush_tlb_all();
+ local_flush_tlb_all();
cpu_set_default_tcr_t0sz();
}
-/*
- * Enable the identity mapping to allow the MMU disabling.
- */
-void setup_mm_for_reboot(void)
-{
- cpu_set_reserved_ttbr0();
- flush_tlb_all();
- cpu_set_idmap_tcr_t0sz();
- cpu_switch_mm(idmap_pg_dir, &init_mm);
-}
-
/*
* Check whether a kernel address is valid (derived from arch/x86/).
*/
return pfn_valid(pte_pfn(*pte));
}
#ifdef CONFIG_SPARSEMEM_VMEMMAP
-#ifdef CONFIG_ARM64_64K_PAGES
+#if !ARM64_SWAPPER_USES_SECTION_MAPS
int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node)
{
return vmemmap_populate_basepages(start, end, node);
}
-#else /* !CONFIG_ARM64_64K_PAGES */
+#else /* !ARM64_SWAPPER_USES_SECTION_MAPS */
int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node)
{
unsigned long addr = start;
flush_tlb_kernel_range(addr, addr+PAGE_SIZE);
}
}
+
+void *__init fixmap_remap_fdt(phys_addr_t dt_phys)
+{
+ const u64 dt_virt_base = __fix_to_virt(FIX_FDT);
+ pgprot_t prot = PAGE_KERNEL_RO;
+ int size, offset;
+ void *dt_virt;
+
+ /*
+ * Check whether the physical FDT address is set and meets the minimum
+ * alignment requirement. Since we are relying on MIN_FDT_ALIGN to be
+ * at least 8 bytes so that we can always access the size field of the
+ * FDT header after mapping the first chunk, double check here if that
+ * is indeed the case.
+ */
+ BUILD_BUG_ON(MIN_FDT_ALIGN < 8);
+ if (!dt_phys || dt_phys % MIN_FDT_ALIGN)
+ return NULL;
+
+ /*
+ * Make sure that the FDT region can be mapped without the need to
+ * allocate additional translation table pages, so that it is safe
+ * to call create_mapping() this early.
+ *
+ * On 64k pages, the FDT will be mapped using PTEs, so we need to
+ * be in the same PMD as the rest of the fixmap.
+ * On 4k pages, we'll use section mappings for the FDT so we only
+ * have to be in the same PUD.
+ */
+ BUILD_BUG_ON(dt_virt_base % SZ_2M);
+
+ BUILD_BUG_ON(__fix_to_virt(FIX_FDT_END) >> SWAPPER_TABLE_SHIFT !=
+ __fix_to_virt(FIX_BTMAP_BEGIN) >> SWAPPER_TABLE_SHIFT);
+
+ offset = dt_phys % SWAPPER_BLOCK_SIZE;
+ dt_virt = (void *)dt_virt_base + offset;
+
+ /* map the first chunk so we can read the size from the header */
+ create_mapping(round_down(dt_phys, SWAPPER_BLOCK_SIZE), dt_virt_base,
+ SWAPPER_BLOCK_SIZE, prot);
+
+ if (fdt_check_header(dt_virt) != 0)
+ return NULL;
+
+ size = fdt_totalsize(dt_virt);
+ if (size > MAX_FDT_SIZE)
+ return NULL;
+
+ if (offset + size > SWAPPER_BLOCK_SIZE)
+ create_mapping(round_down(dt_phys, SWAPPER_BLOCK_SIZE), dt_virt_base,
+ round_up(offset + size, SWAPPER_BLOCK_SIZE), prot);
+
+ memblock_reserve(dt_phys, size);
+
+ return dt_virt;
+}
Code Review / kvmfornfv.git / blobdiff