The mapping code is odd and looks broken. See FIXME in the comment.

Signed-off-by: Thomas Gleixner <t...@linutronix.de>
Cc: Nick Hu <nic...@andestech.com>
Cc: Greentime Hu <green...@gmail.com>
Cc: Vincent Chen <deanbo...@gmail.com>

diff --git a/arch/nds32/Kconfig.cpu b/arch/nds32/Kconfig.cpu
index f88a12fdf0f3..c7add11ea36e 100644
--- a/arch/nds32/Kconfig.cpu
+++ b/arch/nds32/Kconfig.cpu
@@ -157,6 +157,7 @@ config HW_SUPPORT_UNALIGNMENT_ACCESS
 config HIGHMEM
        bool "High Memory Support"
        depends on MMU && !CPU_CACHE_ALIASING
+        select KMAP_LOCAL
        help
          The address space of Andes processors is only 4 Gigabytes large
          and it has to accommodate user address space, kernel address
diff --git a/arch/nds32/include/asm/highmem.h b/arch/nds32/include/asm/highmem.h
index fe986d0e6e3f..d844c282c090 100644
--- a/arch/nds32/include/asm/highmem.h
+++ b/arch/nds32/include/asm/highmem.h
@@ -45,11 +45,22 @@ extern pte_t *pkmap_page_table;
 extern void kmap_init(void);
 
 /*
- * The following functions are already defined by <linux/highmem.h>
- * when CONFIG_HIGHMEM is not set.
+ * FIXME: The below looks broken vs. a kmap_atomic() in task context which
+ * is interupted and another kmap_atomic() happens in interrupt context.
+ * But what do I know about nds32. -- tglx
  */
-#ifdef CONFIG_HIGHMEM
-extern void *kmap_atomic_pfn(unsigned long pfn);
-#endif
+#define arch_kmap_local_post_map(vaddr, pteval)                        \
+       do {                                                    \
+               __nds32__tlbop_inv(vaddr);                      \
+               __nds32__mtsr_dsb(vaddr, NDS32_SR_TLB_VPN);     \
+               __nds32__tlbop_rwr(pteval);                     \
+               __nds32__isb();                                 \
+       } while (0)
+
+#define arch_kmap_local_pre_unmap(vaddr, pte)                  \
+       do {                                                    \
+               __nds32__tlbop_inv(vaddr);                      \
+               __nds32__isb();                                 \
+       } while (0)
 
 #endif
diff --git a/arch/nds32/mm/Makefile b/arch/nds32/mm/Makefile
index 897ecaf5cf54..14fb2e8eb036 100644
--- a/arch/nds32/mm/Makefile
+++ b/arch/nds32/mm/Makefile
@@ -3,7 +3,6 @@ obj-y                           := extable.o tlb.o fault.o 
init.o mmap.o \
                                    mm-nds32.o cacheflush.o proc.o
 
 obj-$(CONFIG_ALIGNMENT_TRAP)   += alignment.o
-obj-$(CONFIG_HIGHMEM)           += highmem.o
 
 ifdef CONFIG_FUNCTION_TRACER
 CFLAGS_REMOVE_proc.o     = $(CC_FLAGS_FTRACE)
diff --git a/arch/nds32/mm/highmem.c b/arch/nds32/mm/highmem.c
deleted file mode 100644
index 4284cd59e21a..000000000000
--- a/arch/nds32/mm/highmem.c
+++ /dev/null
@@ -1,48 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-// Copyright (C) 2005-2017 Andes Technology Corporation
-
-#include <linux/export.h>
-#include <linux/highmem.h>
-#include <linux/sched.h>
-#include <linux/smp.h>
-#include <linux/interrupt.h>
-#include <linux/memblock.h>
-#include <asm/fixmap.h>
-#include <asm/tlbflush.h>
-
-void *kmap_atomic_high_prot(struct page *page, pgprot_t prot)
-{
-       unsigned int idx;
-       unsigned long vaddr, pte;
-       int type;
-       pte_t *ptep;
-
-       type = kmap_atomic_idx_push();
-
-       idx = type + KM_TYPE_NR * smp_processor_id();
-       vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
-       pte = (page_to_pfn(page) << PAGE_SHIFT) | prot;
-       ptep = pte_offset_kernel(pmd_off_k(vaddr), vaddr);
-       set_pte(ptep, pte);
-
-       __nds32__tlbop_inv(vaddr);
-       __nds32__mtsr_dsb(vaddr, NDS32_SR_TLB_VPN);
-       __nds32__tlbop_rwr(pte);
-       __nds32__isb();
-       return (void *)vaddr;
-}
-EXPORT_SYMBOL(kmap_atomic_high_prot);
-
-void kunmap_atomic_high(void *kvaddr)
-{
-       if (kvaddr >= (void *)FIXADDR_START) {
-               unsigned long vaddr = (unsigned long)kvaddr;
-               pte_t *ptep;
-               kmap_atomic_idx_pop();
-               __nds32__tlbop_inv(vaddr);
-               __nds32__isb();
-               ptep = pte_offset_kernel(pmd_off_k(vaddr), vaddr);
-               set_pte(ptep, 0);
-       }
-}
-EXPORT_SYMBOL(kunmap_atomic_high);


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