summaryrefslogtreecommitdiff
path: root/arch/csky/mm/init.c
diff options
context:
space:
mode:
authorGuo Ren <ren_guo@c-sky.com>2018-09-05 14:25:12 +0800
committerGuo Ren <ren_guo@c-sky.com>2018-10-25 23:36:19 +0800
commit013de2d6671d89de3397904749c86a69ac0686f7 (patch)
treea957e4719ccb7f7383bfa17f8937d61409ee9119 /arch/csky/mm/init.c
parent00a9730e1007c6cc87a7c78af2f24a4105d616ee (diff)
downloadlinux-sh-013de2d6671d89de3397904749c86a69ac0686f7.tar.gz
csky: MMU and page table management
This patch adds files related to memory management and here is our memory-layout: Fixmap : 0xffc02000 – 0xfffff000 (4 MB - 12KB) Pkmap : 0xff800000 – 0xffc00000 (4 MB) Vmalloc : 0xf0200000 – 0xff000000 (238 MB) Lowmem : 0x80000000 – 0xc0000000 (1GB) abiv1 CPU (CK610) is VIPT cache and it doesn't support highmem. abiv2 CPUs are all PIPT cache and they could support highmem. Lowmem is directly mapped by msa0 & msa1 reg, and we needn't setup memory page table for it. Link:https://lore.kernel.org/lkml/20180518215548.GH17671@n2100.armlinux.org.uk/ Signed-off-by: Guo Ren <ren_guo@c-sky.com> Cc: Christoph Hellwig <hch@infradead.org> Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Diffstat (limited to 'arch/csky/mm/init.c')
-rw-r--r--arch/csky/mm/init.c122
1 files changed, 122 insertions, 0 deletions
diff --git a/arch/csky/mm/init.c b/arch/csky/mm/init.c
new file mode 100644
index 000000000000..ce2711e050ad
--- /dev/null
+++ b/arch/csky/mm/init.c
@@ -0,0 +1,122 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
+
+#include <linux/bug.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/signal.h>
+#include <linux/sched.h>
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/string.h>
+#include <linux/types.h>
+#include <linux/pagemap.h>
+#include <linux/ptrace.h>
+#include <linux/mman.h>
+#include <linux/mm.h>
+#include <linux/bootmem.h>
+#include <linux/highmem.h>
+#include <linux/memblock.h>
+#include <linux/swap.h>
+#include <linux/proc_fs.h>
+#include <linux/pfn.h>
+
+#include <asm/setup.h>
+#include <asm/cachectl.h>
+#include <asm/dma.h>
+#include <asm/pgtable.h>
+#include <asm/pgalloc.h>
+#include <asm/mmu_context.h>
+#include <asm/sections.h>
+#include <asm/tlb.h>
+
+pgd_t swapper_pg_dir[PTRS_PER_PGD] __page_aligned_bss;
+pte_t invalid_pte_table[PTRS_PER_PTE] __page_aligned_bss;
+unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)]
+ __page_aligned_bss;
+EXPORT_SYMBOL(empty_zero_page);
+
+void __init mem_init(void)
+{
+#ifdef CONFIG_HIGHMEM
+ unsigned long tmp;
+
+ max_mapnr = highend_pfn;
+#else
+ max_mapnr = max_low_pfn;
+#endif
+ high_memory = (void *) __va(max_low_pfn << PAGE_SHIFT);
+
+ free_all_bootmem();
+
+#ifdef CONFIG_HIGHMEM
+ for (tmp = highstart_pfn; tmp < highend_pfn; tmp++) {
+ struct page *page = pfn_to_page(tmp);
+
+ /* FIXME not sure about */
+ if (!memblock_is_reserved(tmp << PAGE_SHIFT))
+ free_highmem_page(page);
+ }
+#endif
+ mem_init_print_info(NULL);
+}
+
+#ifdef CONFIG_BLK_DEV_INITRD
+void free_initrd_mem(unsigned long start, unsigned long end)
+{
+ if (start < end)
+ pr_info("Freeing initrd memory: %ldk freed\n",
+ (end - start) >> 10);
+
+ for (; start < end; start += PAGE_SIZE) {
+ ClearPageReserved(virt_to_page(start));
+ init_page_count(virt_to_page(start));
+ free_page(start);
+ totalram_pages++;
+ }
+}
+#endif
+
+extern char __init_begin[], __init_end[];
+
+void free_initmem(void)
+{
+ unsigned long addr;
+
+ addr = (unsigned long) &__init_begin;
+
+ while (addr < (unsigned long) &__init_end) {
+ ClearPageReserved(virt_to_page(addr));
+ init_page_count(virt_to_page(addr));
+ free_page(addr);
+ totalram_pages++;
+ addr += PAGE_SIZE;
+ }
+
+ pr_info("Freeing unused kernel memory: %dk freed\n",
+ ((unsigned int)&__init_end - (unsigned int)&__init_begin) >> 10);
+}
+
+void pgd_init(unsigned long *p)
+{
+ int i;
+
+ for (i = 0; i < PTRS_PER_PGD; i++)
+ p[i] = __pa(invalid_pte_table);
+}
+
+void __init pre_mmu_init(void)
+{
+ /*
+ * Setup page-table and enable TLB-hardrefill
+ */
+ flush_tlb_all();
+ pgd_init((unsigned long *)swapper_pg_dir);
+ TLBMISS_HANDLER_SETUP_PGD(swapper_pg_dir);
+ TLBMISS_HANDLER_SETUP_PGD_KERNEL(swapper_pg_dir);
+
+ asid_cache(smp_processor_id()) = ASID_FIRST_VERSION;
+
+ /* Setup page mask to 4k */
+ write_mmu_pagemask(0);
+}