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Diffstat (limited to 'arch/riscv/mm/init.c')
-rw-r--r--arch/riscv/mm/init.c212
1 files changed, 188 insertions, 24 deletions
diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
index 424d7777f4df..7ba915849817 100644
--- a/arch/riscv/mm/init.c
+++ b/arch/riscv/mm/init.c
@@ -37,6 +37,17 @@ EXPORT_SYMBOL(kernel_map);
#define kernel_map (*(struct kernel_mapping *)XIP_FIXUP(&kernel_map))
#endif
+#ifdef CONFIG_64BIT
+u64 satp_mode = !IS_ENABLED(CONFIG_XIP_KERNEL) ? SATP_MODE_48 : SATP_MODE_39;
+#else
+u64 satp_mode = SATP_MODE_32;
+#endif
+EXPORT_SYMBOL(satp_mode);
+
+bool pgtable_l4_enabled = IS_ENABLED(CONFIG_64BIT) && !IS_ENABLED(CONFIG_XIP_KERNEL) ?
+ true : false;
+EXPORT_SYMBOL(pgtable_l4_enabled);
+
phys_addr_t phys_ram_base __ro_after_init;
EXPORT_SYMBOL(phys_ram_base);
@@ -53,15 +64,6 @@ extern char _start[];
void *_dtb_early_va __initdata;
uintptr_t _dtb_early_pa __initdata;
-struct pt_alloc_ops {
- pte_t *(*get_pte_virt)(phys_addr_t pa);
- phys_addr_t (*alloc_pte)(uintptr_t va);
-#ifndef __PAGETABLE_PMD_FOLDED
- pmd_t *(*get_pmd_virt)(phys_addr_t pa);
- phys_addr_t (*alloc_pmd)(uintptr_t va);
-#endif
-};
-
static phys_addr_t dma32_phys_limit __initdata;
static void __init zone_sizes_init(void)
@@ -222,7 +224,7 @@ static void __init setup_bootmem(void)
}
#ifdef CONFIG_MMU
-static struct pt_alloc_ops _pt_ops __initdata;
+struct pt_alloc_ops _pt_ops __initdata;
#ifdef CONFIG_XIP_KERNEL
#define pt_ops (*(struct pt_alloc_ops *)XIP_FIXUP(&_pt_ops))
@@ -238,6 +240,7 @@ pgd_t trampoline_pg_dir[PTRS_PER_PGD] __page_aligned_bss;
static pte_t fixmap_pte[PTRS_PER_PTE] __page_aligned_bss;
pgd_t early_pg_dir[PTRS_PER_PGD] __initdata __aligned(PAGE_SIZE);
+static pud_t __maybe_unused early_dtb_pud[PTRS_PER_PUD] __initdata __aligned(PAGE_SIZE);
static pmd_t __maybe_unused early_dtb_pmd[PTRS_PER_PMD] __initdata __aligned(PAGE_SIZE);
#ifdef CONFIG_XIP_KERNEL
@@ -326,6 +329,16 @@ static pmd_t early_pmd[PTRS_PER_PMD] __initdata __aligned(PAGE_SIZE);
#define early_pmd ((pmd_t *)XIP_FIXUP(early_pmd))
#endif /* CONFIG_XIP_KERNEL */
+static pud_t trampoline_pud[PTRS_PER_PUD] __page_aligned_bss;
+static pud_t fixmap_pud[PTRS_PER_PUD] __page_aligned_bss;
+static pud_t early_pud[PTRS_PER_PUD] __initdata __aligned(PAGE_SIZE);
+
+#ifdef CONFIG_XIP_KERNEL
+#define trampoline_pud ((pud_t *)XIP_FIXUP(trampoline_pud))
+#define fixmap_pud ((pud_t *)XIP_FIXUP(fixmap_pud))
+#define early_pud ((pud_t *)XIP_FIXUP(early_pud))
+#endif /* CONFIG_XIP_KERNEL */
+
static pmd_t *__init get_pmd_virt_early(phys_addr_t pa)
{
/* Before MMU is enabled */
@@ -345,7 +358,7 @@ static pmd_t *__init get_pmd_virt_late(phys_addr_t pa)
static phys_addr_t __init alloc_pmd_early(uintptr_t va)
{
- BUG_ON((va - kernel_map.virt_addr) >> PGDIR_SHIFT);
+ BUG_ON((va - kernel_map.virt_addr) >> PUD_SHIFT);
return (uintptr_t)early_pmd;
}
@@ -391,21 +404,97 @@ static void __init create_pmd_mapping(pmd_t *pmdp,
create_pte_mapping(ptep, va, pa, sz, prot);
}
-#define pgd_next_t pmd_t
-#define alloc_pgd_next(__va) pt_ops.alloc_pmd(__va)
-#define get_pgd_next_virt(__pa) pt_ops.get_pmd_virt(__pa)
+static pud_t *__init get_pud_virt_early(phys_addr_t pa)
+{
+ return (pud_t *)((uintptr_t)pa);
+}
+
+static pud_t *__init get_pud_virt_fixmap(phys_addr_t pa)
+{
+ clear_fixmap(FIX_PUD);
+ return (pud_t *)set_fixmap_offset(FIX_PUD, pa);
+}
+
+static pud_t *__init get_pud_virt_late(phys_addr_t pa)
+{
+ return (pud_t *)__va(pa);
+}
+
+static phys_addr_t __init alloc_pud_early(uintptr_t va)
+{
+ /* Only one PUD is available for early mapping */
+ BUG_ON((va - kernel_map.virt_addr) >> PGDIR_SHIFT);
+
+ return (uintptr_t)early_pud;
+}
+
+static phys_addr_t __init alloc_pud_fixmap(uintptr_t va)
+{
+ return memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE);
+}
+
+static phys_addr_t alloc_pud_late(uintptr_t va)
+{
+ unsigned long vaddr;
+
+ vaddr = __get_free_page(GFP_KERNEL);
+ BUG_ON(!vaddr);
+ return __pa(vaddr);
+}
+
+static void __init create_pud_mapping(pud_t *pudp,
+ uintptr_t va, phys_addr_t pa,
+ phys_addr_t sz, pgprot_t prot)
+{
+ pmd_t *nextp;
+ phys_addr_t next_phys;
+ uintptr_t pud_index = pud_index(va);
+
+ if (sz == PUD_SIZE) {
+ if (pud_val(pudp[pud_index]) == 0)
+ pudp[pud_index] = pfn_pud(PFN_DOWN(pa), prot);
+ return;
+ }
+
+ if (pud_val(pudp[pud_index]) == 0) {
+ next_phys = pt_ops.alloc_pmd(va);
+ pudp[pud_index] = pfn_pud(PFN_DOWN(next_phys), PAGE_TABLE);
+ nextp = pt_ops.get_pmd_virt(next_phys);
+ memset(nextp, 0, PAGE_SIZE);
+ } else {
+ next_phys = PFN_PHYS(_pud_pfn(pudp[pud_index]));
+ nextp = pt_ops.get_pmd_virt(next_phys);
+ }
+
+ create_pmd_mapping(nextp, va, pa, sz, prot);
+}
+
+#define pgd_next_t pud_t
+#define alloc_pgd_next(__va) (pgtable_l4_enabled ? \
+ pt_ops.alloc_pud(__va) : pt_ops.alloc_pmd(__va))
+#define get_pgd_next_virt(__pa) (pgtable_l4_enabled ? \
+ pt_ops.get_pud_virt(__pa) : (pgd_next_t *)pt_ops.get_pmd_virt(__pa))
#define create_pgd_next_mapping(__nextp, __va, __pa, __sz, __prot) \
- create_pmd_mapping(__nextp, __va, __pa, __sz, __prot)
-#define fixmap_pgd_next fixmap_pmd
+ (pgtable_l4_enabled ? \
+ create_pud_mapping(__nextp, __va, __pa, __sz, __prot) : \
+ create_pmd_mapping((pmd_t *)__nextp, __va, __pa, __sz, __prot))
+#define fixmap_pgd_next (pgtable_l4_enabled ? \
+ (uintptr_t)fixmap_pud : (uintptr_t)fixmap_pmd)
+#define trampoline_pgd_next (pgtable_l4_enabled ? \
+ (uintptr_t)trampoline_pud : (uintptr_t)trampoline_pmd)
+#define early_dtb_pgd_next (pgtable_l4_enabled ? \
+ (uintptr_t)early_dtb_pud : (uintptr_t)early_dtb_pmd)
#else
#define pgd_next_t pte_t
#define alloc_pgd_next(__va) pt_ops.alloc_pte(__va)
#define get_pgd_next_virt(__pa) pt_ops.get_pte_virt(__pa)
#define create_pgd_next_mapping(__nextp, __va, __pa, __sz, __prot) \
create_pte_mapping(__nextp, __va, __pa, __sz, __prot)
-#define fixmap_pgd_next fixmap_pte
+#define fixmap_pgd_next ((uintptr_t)fixmap_pte)
+#define early_dtb_pgd_next ((uintptr_t)early_dtb_pmd)
+#define create_pud_mapping(__pmdp, __va, __pa, __sz, __prot)
#define create_pmd_mapping(__pmdp, __va, __pa, __sz, __prot)
-#endif
+#endif /* __PAGETABLE_PMD_FOLDED */
void __init create_pgd_mapping(pgd_t *pgdp,
uintptr_t va, phys_addr_t pa,
@@ -492,6 +581,57 @@ static __init pgprot_t pgprot_from_va(uintptr_t va)
}
#endif /* CONFIG_STRICT_KERNEL_RWX */
+#ifdef CONFIG_64BIT
+static void __init disable_pgtable_l4(void)
+{
+ pgtable_l4_enabled = false;
+ kernel_map.page_offset = PAGE_OFFSET_L3;
+ satp_mode = SATP_MODE_39;
+}
+
+/*
+ * There is a simple way to determine if 4-level is supported by the
+ * underlying hardware: establish 1:1 mapping in 4-level page table mode
+ * then read SATP to see if the configuration was taken into account
+ * meaning sv48 is supported.
+ */
+static __init void set_satp_mode(void)
+{
+ u64 identity_satp, hw_satp;
+ uintptr_t set_satp_mode_pmd;
+
+ set_satp_mode_pmd = ((unsigned long)set_satp_mode) & PMD_MASK;
+ create_pgd_mapping(early_pg_dir,
+ set_satp_mode_pmd, (uintptr_t)early_pud,
+ PGDIR_SIZE, PAGE_TABLE);
+ create_pud_mapping(early_pud,
+ set_satp_mode_pmd, (uintptr_t)early_pmd,
+ PUD_SIZE, PAGE_TABLE);
+ /* Handle the case where set_satp_mode straddles 2 PMDs */
+ create_pmd_mapping(early_pmd,
+ set_satp_mode_pmd, set_satp_mode_pmd,
+ PMD_SIZE, PAGE_KERNEL_EXEC);
+ create_pmd_mapping(early_pmd,
+ set_satp_mode_pmd + PMD_SIZE,
+ set_satp_mode_pmd + PMD_SIZE,
+ PMD_SIZE, PAGE_KERNEL_EXEC);
+
+ identity_satp = PFN_DOWN((uintptr_t)&early_pg_dir) | satp_mode;
+
+ local_flush_tlb_all();
+ csr_write(CSR_SATP, identity_satp);
+ hw_satp = csr_swap(CSR_SATP, 0ULL);
+ local_flush_tlb_all();
+
+ if (hw_satp != identity_satp)
+ disable_pgtable_l4();
+
+ memset(early_pg_dir, 0, PAGE_SIZE);
+ memset(early_pud, 0, PAGE_SIZE);
+ memset(early_pmd, 0, PAGE_SIZE);
+}
+#endif
+
/*
* setup_vm() is called from head.S with MMU-off.
*
@@ -556,10 +696,15 @@ static void __init create_fdt_early_page_table(pgd_t *pgdir, uintptr_t dtb_pa)
uintptr_t pa = dtb_pa & ~(PMD_SIZE - 1);
create_pgd_mapping(early_pg_dir, DTB_EARLY_BASE_VA,
- IS_ENABLED(CONFIG_64BIT) ? (uintptr_t)early_dtb_pmd : pa,
+ IS_ENABLED(CONFIG_64BIT) ? early_dtb_pgd_next : pa,
PGDIR_SIZE,
IS_ENABLED(CONFIG_64BIT) ? PAGE_TABLE : PAGE_KERNEL);
+ if (pgtable_l4_enabled) {
+ create_pud_mapping(early_dtb_pud, DTB_EARLY_BASE_VA,
+ (uintptr_t)early_dtb_pmd, PUD_SIZE, PAGE_TABLE);
+ }
+
if (IS_ENABLED(CONFIG_64BIT)) {
create_pmd_mapping(early_dtb_pmd, DTB_EARLY_BASE_VA,
pa, PMD_SIZE, PAGE_KERNEL);
@@ -592,6 +737,8 @@ void pt_ops_set_early(void)
#ifndef __PAGETABLE_PMD_FOLDED
pt_ops.alloc_pmd = alloc_pmd_early;
pt_ops.get_pmd_virt = get_pmd_virt_early;
+ pt_ops.alloc_pud = alloc_pud_early;
+ pt_ops.get_pud_virt = get_pud_virt_early;
#endif
}
@@ -610,6 +757,8 @@ void pt_ops_set_fixmap(void)
#ifndef __PAGETABLE_PMD_FOLDED
pt_ops.alloc_pmd = kernel_mapping_pa_to_va((uintptr_t)alloc_pmd_fixmap);
pt_ops.get_pmd_virt = kernel_mapping_pa_to_va((uintptr_t)get_pmd_virt_fixmap);
+ pt_ops.alloc_pud = kernel_mapping_pa_to_va((uintptr_t)alloc_pud_fixmap);
+ pt_ops.get_pud_virt = kernel_mapping_pa_to_va((uintptr_t)get_pud_virt_fixmap);
#endif
}
@@ -624,6 +773,8 @@ void pt_ops_set_late(void)
#ifndef __PAGETABLE_PMD_FOLDED
pt_ops.alloc_pmd = alloc_pmd_late;
pt_ops.get_pmd_virt = get_pmd_virt_late;
+ pt_ops.alloc_pud = alloc_pud_late;
+ pt_ops.get_pud_virt = get_pud_virt_late;
#endif
}
@@ -632,6 +783,7 @@ asmlinkage void __init setup_vm(uintptr_t dtb_pa)
pmd_t __maybe_unused fix_bmap_spmd, fix_bmap_epmd;
kernel_map.virt_addr = KERNEL_LINK_ADDR;
+ kernel_map.page_offset = _AC(CONFIG_PAGE_OFFSET, UL);
#ifdef CONFIG_XIP_KERNEL
kernel_map.xiprom = (uintptr_t)CONFIG_XIP_PHYS_ADDR;
@@ -646,6 +798,11 @@ asmlinkage void __init setup_vm(uintptr_t dtb_pa)
kernel_map.phys_addr = (uintptr_t)(&_start);
kernel_map.size = (uintptr_t)(&_end) - kernel_map.phys_addr;
#endif
+
+#if defined(CONFIG_64BIT) && !defined(CONFIG_XIP_KERNEL)
+ set_satp_mode();
+#endif
+
kernel_map.va_pa_offset = PAGE_OFFSET - kernel_map.phys_addr;
kernel_map.va_kernel_pa_offset = kernel_map.virt_addr - kernel_map.phys_addr;
@@ -675,15 +832,21 @@ asmlinkage void __init setup_vm(uintptr_t dtb_pa)
/* Setup early PGD for fixmap */
create_pgd_mapping(early_pg_dir, FIXADDR_START,
- (uintptr_t)fixmap_pgd_next, PGDIR_SIZE, PAGE_TABLE);
+ fixmap_pgd_next, PGDIR_SIZE, PAGE_TABLE);
#ifndef __PAGETABLE_PMD_FOLDED
- /* Setup fixmap PMD */
+ /* Setup fixmap PUD and PMD */
+ if (pgtable_l4_enabled)
+ create_pud_mapping(fixmap_pud, FIXADDR_START,
+ (uintptr_t)fixmap_pmd, PUD_SIZE, PAGE_TABLE);
create_pmd_mapping(fixmap_pmd, FIXADDR_START,
(uintptr_t)fixmap_pte, PMD_SIZE, PAGE_TABLE);
/* Setup trampoline PGD and PMD */
create_pgd_mapping(trampoline_pg_dir, kernel_map.virt_addr,
- (uintptr_t)trampoline_pmd, PGDIR_SIZE, PAGE_TABLE);
+ trampoline_pgd_next, PGDIR_SIZE, PAGE_TABLE);
+ if (pgtable_l4_enabled)
+ create_pud_mapping(trampoline_pud, kernel_map.virt_addr,
+ (uintptr_t)trampoline_pmd, PUD_SIZE, PAGE_TABLE);
#ifdef CONFIG_XIP_KERNEL
create_pmd_mapping(trampoline_pmd, kernel_map.virt_addr,
kernel_map.xiprom, PMD_SIZE, PAGE_KERNEL_EXEC);
@@ -711,7 +874,7 @@ asmlinkage void __init setup_vm(uintptr_t dtb_pa)
* Bootime fixmap only can handle PMD_SIZE mapping. Thus, boot-ioremap
* range can not span multiple pmds.
*/
- BUILD_BUG_ON((__fix_to_virt(FIX_BTMAP_BEGIN) >> PMD_SHIFT)
+ BUG_ON((__fix_to_virt(FIX_BTMAP_BEGIN) >> PMD_SHIFT)
!= (__fix_to_virt(FIX_BTMAP_END) >> PMD_SHIFT));
#ifndef __PAGETABLE_PMD_FOLDED
@@ -782,9 +945,10 @@ static void __init setup_vm_final(void)
/* Clear fixmap PTE and PMD mappings */
clear_fixmap(FIX_PTE);
clear_fixmap(FIX_PMD);
+ clear_fixmap(FIX_PUD);
/* Move to swapper page table */
- csr_write(CSR_SATP, PFN_DOWN(__pa_symbol(swapper_pg_dir)) | SATP_MODE);
+ csr_write(CSR_SATP, PFN_DOWN(__pa_symbol(swapper_pg_dir)) | satp_mode);
local_flush_tlb_all();
pt_ops_set_late();