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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
commit5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch)
treea94efe259b9009378be6d90eb30d2b019d95c194 /arch/csky/mm/highmem.c
parentInitial commit. (diff)
downloadlinux-upstream/5.10.209.tar.xz
linux-upstream/5.10.209.zip
Adding upstream version 5.10.209.upstream/5.10.209upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/csky/mm/highmem.c')
-rw-r--r--arch/csky/mm/highmem.c109
1 files changed, 109 insertions, 0 deletions
diff --git a/arch/csky/mm/highmem.c b/arch/csky/mm/highmem.c
new file mode 100644
index 000000000..89c10800a
--- /dev/null
+++ b/arch/csky/mm/highmem.c
@@ -0,0 +1,109 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
+
+#include <linux/module.h>
+#include <linux/highmem.h>
+#include <linux/smp.h>
+#include <linux/memblock.h>
+#include <asm/fixmap.h>
+#include <asm/tlbflush.h>
+#include <asm/cacheflush.h>
+
+static pte_t *kmap_pte;
+
+unsigned long highstart_pfn, highend_pfn;
+
+void kmap_flush_tlb(unsigned long addr)
+{
+ flush_tlb_one(addr);
+}
+EXPORT_SYMBOL(kmap_flush_tlb);
+
+void *kmap_atomic_high_prot(struct page *page, pgprot_t prot)
+{
+ unsigned long vaddr;
+ int idx, type;
+
+ type = kmap_atomic_idx_push();
+ idx = type + KM_TYPE_NR*smp_processor_id();
+ vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
+#ifdef CONFIG_DEBUG_HIGHMEM
+ BUG_ON(!pte_none(*(kmap_pte - idx)));
+#endif
+ set_pte(kmap_pte-idx, mk_pte(page, prot));
+ flush_tlb_one((unsigned long)vaddr);
+
+ return (void *)vaddr;
+}
+EXPORT_SYMBOL(kmap_atomic_high_prot);
+
+void kunmap_atomic_high(void *kvaddr)
+{
+ unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK;
+ int idx;
+
+ if (vaddr < FIXADDR_START)
+ return;
+
+#ifdef CONFIG_DEBUG_HIGHMEM
+ idx = KM_TYPE_NR*smp_processor_id() + kmap_atomic_idx();
+
+ BUG_ON(vaddr != __fix_to_virt(FIX_KMAP_BEGIN + idx));
+
+ pte_clear(&init_mm, vaddr, kmap_pte - idx);
+ flush_tlb_one(vaddr);
+#else
+ (void) idx; /* to kill a warning */
+#endif
+ kmap_atomic_idx_pop();
+}
+EXPORT_SYMBOL(kunmap_atomic_high);
+
+/*
+ * This is the same as kmap_atomic() but can map memory that doesn't
+ * have a struct page associated with it.
+ */
+void *kmap_atomic_pfn(unsigned long pfn)
+{
+ unsigned long vaddr;
+ int idx, type;
+
+ pagefault_disable();
+
+ type = kmap_atomic_idx_push();
+ idx = type + KM_TYPE_NR*smp_processor_id();
+ vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
+ set_pte(kmap_pte-idx, pfn_pte(pfn, PAGE_KERNEL));
+ flush_tlb_one(vaddr);
+
+ return (void *) vaddr;
+}
+
+static void __init kmap_pages_init(void)
+{
+ unsigned long vaddr;
+ pgd_t *pgd;
+ pmd_t *pmd;
+ pud_t *pud;
+ pte_t *pte;
+
+ vaddr = PKMAP_BASE;
+ fixrange_init(vaddr, vaddr + PAGE_SIZE*LAST_PKMAP, swapper_pg_dir);
+
+ pgd = swapper_pg_dir + pgd_index(vaddr);
+ pud = (pud_t *)pgd;
+ pmd = pmd_offset(pud, vaddr);
+ pte = pte_offset_kernel(pmd, vaddr);
+ pkmap_page_table = pte;
+}
+
+void __init kmap_init(void)
+{
+ unsigned long vaddr;
+
+ kmap_pages_init();
+
+ vaddr = __fix_to_virt(FIX_KMAP_BEGIN);
+
+ kmap_pte = pte_offset_kernel((pmd_t *)pgd_offset_k(vaddr), vaddr);
+}