nds32: Cache and TLB routines

This patch contains cache and TLB maintenance functions.

Signed-off-by: Vincent Chen <vincentc@andestech.com>
Signed-off-by: Greentime Hu <greentime@andestech.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>

arch/nds32/include/asm/cache.h

@@ -0,0 +1,12 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2005-2017 Andes Technology Corporation
+
+#ifndef __NDS32_CACHE_H__
+#define __NDS32_CACHE_H__
+
+#define L1_CACHE_BYTES	32
+#define L1_CACHE_SHIFT	5
+
+#define ARCH_DMA_MINALIGN   L1_CACHE_BYTES
+
+#endif /* __NDS32_CACHE_H__ */

arch/nds32/include/asm/cache_info.h

@@ -0,0 +1,13 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2005-2017 Andes Technology Corporation
+
+struct cache_info {
+	unsigned char ways;
+	unsigned char line_size;
+	unsigned short sets;
+	unsigned short size;
+#if defined(CONFIG_CPU_CACHE_ALIASING)
+	unsigned short aliasing_num;
+	unsigned int aliasing_mask;
+#endif
+};

arch/nds32/include/asm/cacheflush.h

@@ -0,0 +1,44 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2005-2017 Andes Technology Corporation
+
+#ifndef __NDS32_CACHEFLUSH_H__
+#define __NDS32_CACHEFLUSH_H__
+
+#include <linux/mm.h>
+
+#define PG_dcache_dirty PG_arch_1
+
+#ifdef CONFIG_CPU_CACHE_ALIASING
+void flush_cache_mm(struct mm_struct *mm);
+void flush_cache_dup_mm(struct mm_struct *mm);
+void flush_cache_range(struct vm_area_struct *vma,
+		       unsigned long start, unsigned long end);
+void flush_cache_page(struct vm_area_struct *vma,
+		      unsigned long addr, unsigned long pfn);
+void flush_cache_kmaps(void);
+void flush_cache_vmap(unsigned long start, unsigned long end);
+void flush_cache_vunmap(unsigned long start, unsigned long end);
+
+#define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 1
+void flush_dcache_page(struct page *page);
+void copy_to_user_page(struct vm_area_struct *vma, struct page *page,
+		       unsigned long vaddr, void *dst, void *src, int len);
+void copy_from_user_page(struct vm_area_struct *vma, struct page *page,
+			 unsigned long vaddr, void *dst, void *src, int len);
+
+#define ARCH_HAS_FLUSH_ANON_PAGE
+void flush_anon_page(struct vm_area_struct *vma,
+		     struct page *page, unsigned long vaddr);
+
+#define ARCH_HAS_FLUSH_KERNEL_DCACHE_PAGE
+void flush_kernel_dcache_page(struct page *page);
+void flush_icache_range(unsigned long start, unsigned long end);
+void flush_icache_page(struct vm_area_struct *vma, struct page *page);
+#define flush_dcache_mmap_lock(mapping)   spin_lock_irq(&(mapping)->tree_lock)
+#define flush_dcache_mmap_unlock(mapping) spin_unlock_irq(&(mapping)->tree_lock)
+
+#else
+#include <asm-generic/cacheflush.h>
+#endif
+
+#endif /* __NDS32_CACHEFLUSH_H__ */

arch/nds32/include/asm/mmu_context.h

@@ -0,0 +1,68 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2005-2017 Andes Technology Corporation
+
+#ifndef __ASM_NDS32_MMU_CONTEXT_H
+#define __ASM_NDS32_MMU_CONTEXT_H
+
+#include <linux/spinlock.h>
+#include <asm/tlbflush.h>
+#include <asm/proc-fns.h>
+#include <asm-generic/mm_hooks.h>
+
+static inline int
+init_new_context(struct task_struct *tsk, struct mm_struct *mm)
+{
+	mm->context.id = 0;
+	return 0;
+}
+
+#define destroy_context(mm)	do { } while(0)
+
+#define CID_BITS	9
+extern spinlock_t cid_lock;
+extern unsigned int cpu_last_cid;
+
+static inline void __new_context(struct mm_struct *mm)
+{
+	unsigned int cid;
+	unsigned long flags;
+
+	spin_lock_irqsave(&cid_lock, flags);
+	cid = cpu_last_cid;
+	cpu_last_cid += 1 << TLB_MISC_offCID;
+	if (cpu_last_cid == 0)
+		cpu_last_cid = 1 << TLB_MISC_offCID << CID_BITS;
+
+	if ((cid & TLB_MISC_mskCID) == 0)
+		flush_tlb_all();
+	spin_unlock_irqrestore(&cid_lock, flags);
+
+	mm->context.id = cid;
+}
+
+static inline void check_context(struct mm_struct *mm)
+{
+	if (unlikely
+	    ((mm->context.id ^ cpu_last_cid) >> TLB_MISC_offCID >> CID_BITS))
+		__new_context(mm);
+}
+
+static inline void enter_lazy_tlb(struct mm_struct *mm, struct task_struct *tsk)
+{
+}
+
+static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
+			     struct task_struct *tsk)
+{
+	unsigned int cpu = smp_processor_id();
+
+	if (!cpumask_test_and_set_cpu(cpu, mm_cpumask(next)) || prev != next) {
+		check_context(next);
+		cpu_switch_mm(next);
+	}
+}
+
+#define deactivate_mm(tsk,mm)	do { } while (0)
+#define activate_mm(prev,next)	switch_mm(prev, next, NULL)
+
+#endif

arch/nds32/include/asm/proc-fns.h

@@ -0,0 +1,44 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2005-2017 Andes Technology Corporation
+
+#ifndef __NDS32_PROCFNS_H__
+#define __NDS32_PROCFNS_H__
+
+#ifdef __KERNEL__
+#include <asm/page.h>
+
+struct mm_struct;
+struct vm_area_struct;
+extern void cpu_proc_init(void);
+extern void cpu_proc_fin(void);
+extern void cpu_do_idle(void);
+extern void cpu_reset(unsigned long reset);
+extern void cpu_switch_mm(struct mm_struct *mm);
+
+extern void cpu_dcache_inval_all(void);
+extern void cpu_dcache_wbinval_all(void);
+extern void cpu_dcache_inval_page(unsigned long page);
+extern void cpu_dcache_wb_page(unsigned long page);
+extern void cpu_dcache_wbinval_page(unsigned long page);
+extern void cpu_dcache_inval_range(unsigned long start, unsigned long end);
+extern void cpu_dcache_wb_range(unsigned long start, unsigned long end);
+extern void cpu_dcache_wbinval_range(unsigned long start, unsigned long end);
+
+extern void cpu_icache_inval_all(void);
+extern void cpu_icache_inval_page(unsigned long page);
+extern void cpu_icache_inval_range(unsigned long start, unsigned long end);
+
+extern void cpu_cache_wbinval_page(unsigned long page, int flushi);
+extern void cpu_cache_wbinval_range(unsigned long start,
+				    unsigned long end, int flushi);
+extern void cpu_cache_wbinval_range_check(struct vm_area_struct *vma,
+					  unsigned long start,
+					  unsigned long end, bool flushi,
+					  bool wbd);
+
+extern void cpu_dma_wb_range(unsigned long start, unsigned long end);
+extern void cpu_dma_inval_range(unsigned long start, unsigned long end);
+extern void cpu_dma_wbinval_range(unsigned long start, unsigned long end);
+
+#endif /* __KERNEL__ */
+#endif /* __NDS32_PROCFNS_H__ */

arch/nds32/include/asm/tlb.h

@@ -0,0 +1,28 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2005-2017 Andes Technology Corporation
+
+#ifndef __ASMNDS32_TLB_H
+#define __ASMNDS32_TLB_H
+
+#define tlb_start_vma(tlb,vma)						\
+	do {								\
+		if (!tlb->fullmm)					\
+			flush_cache_range(vma, vma->vm_start, vma->vm_end); \
+	} while (0)
+
+#define tlb_end_vma(tlb,vma)				\
+	do { 						\
+		if(!tlb->fullmm)			\
+			flush_tlb_range(vma, vma->vm_start, vma->vm_end); \
+	} while (0)
+
+#define __tlb_remove_tlb_entry(tlb, pte, addr) do { } while (0)
+
+#define tlb_flush(tlb)	flush_tlb_mm((tlb)->mm)
+
+#include <asm-generic/tlb.h>
+
+#define __pte_free_tlb(tlb, pte, addr)	pte_free((tlb)->mm, pte)
+#define __pmd_free_tlb(tlb, pmd, addr)	pmd_free((tln)->mm, pmd)
+
+#endif

arch/nds32/include/asm/tlbflush.h

@@ -0,0 +1,47 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2005-2017 Andes Technology Corporation
+
+#ifndef _ASMNDS32_TLBFLUSH_H
+#define _ASMNDS32_TLBFLUSH_H
+
+#include <linux/spinlock.h>
+#include <linux/mm.h>
+#include <nds32_intrinsic.h>
+
+static inline void local_flush_tlb_all(void)
+{
+	__nds32__tlbop_flua();
+	__nds32__isb();
+}
+
+static inline void local_flush_tlb_mm(struct mm_struct *mm)
+{
+	__nds32__tlbop_flua();
+	__nds32__isb();
+}
+
+static inline void local_flush_tlb_kernel_range(unsigned long start,
+						unsigned long end)
+{
+	while (start < end) {
+		__nds32__tlbop_inv(start);
+		__nds32__isb();
+		start += PAGE_SIZE;
+	}
+}
+
+void local_flush_tlb_range(struct vm_area_struct *vma,
+			   unsigned long start, unsigned long end);
+void local_flush_tlb_page(struct vm_area_struct *vma, unsigned long addr);
+
+#define flush_tlb_all		local_flush_tlb_all
+#define flush_tlb_mm		local_flush_tlb_mm
+#define flush_tlb_range		local_flush_tlb_range
+#define flush_tlb_page		local_flush_tlb_page
+#define flush_tlb_kernel_range	local_flush_tlb_kernel_range
+
+void update_mmu_cache(struct vm_area_struct *vma,
+		      unsigned long address, pte_t * pte);
+void tlb_migrate_finish(struct mm_struct *mm);
+
+#endif

arch/nds32/include/uapi/asm/cachectl.h

@@ -0,0 +1,14 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 1994, 1995, 1996 by Ralf Baechle
+// Copyright (C) 2005-2017 Andes Technology Corporation
+#ifndef	_ASM_CACHECTL
+#define	_ASM_CACHECTL
+
+/*
+ * Options for cacheflush system call
+ */
+#define	ICACHE	0		/* flush instruction cache        */
+#define	DCACHE	1		/* writeback and flush data cache */
+#define	BCACHE	2		/* flush instruction cache + writeback and flush data cache */
+
+#endif /* _ASM_CACHECTL */

arch/nds32/kernel/cacheinfo.c

@@ -0,0 +1,49 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2005-2017 Andes Technology Corporation
+
+#include <linux/bitops.h>
+#include <linux/cacheinfo.h>
+#include <linux/cpu.h>
+
+static void ci_leaf_init(struct cacheinfo *this_leaf,
+			 enum cache_type type, unsigned int level)
+{
+	char cache_type = (type & CACHE_TYPE_INST ? ICACHE : DCACHE);
+
+	this_leaf->level = level;
+	this_leaf->type = type;
+	this_leaf->coherency_line_size = CACHE_LINE_SIZE(cache_type);
+	this_leaf->number_of_sets = CACHE_SET(cache_type);;
+	this_leaf->ways_of_associativity = CACHE_WAY(cache_type);
+	this_leaf->size = this_leaf->number_of_sets *
+	    this_leaf->coherency_line_size * this_leaf->ways_of_associativity;
+#if defined(CONFIG_CPU_DCACHE_WRITETHROUGH)
+	this_leaf->attributes = CACHE_WRITE_THROUGH;
+#else
+	this_leaf->attributes = CACHE_WRITE_BACK;
+#endif
+}
+
+int init_cache_level(unsigned int cpu)
+{
+	struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu);
+
+	/* Only 1 level and I/D cache seperate. */
+	this_cpu_ci->num_levels = 1;
+	this_cpu_ci->num_leaves = 2;
+	return 0;
+}
+
+int populate_cache_leaves(unsigned int cpu)
+{
+	unsigned int level, idx;
+	struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu);
+	struct cacheinfo *this_leaf = this_cpu_ci->info_list;
+
+	for (idx = 0, level = 1; level <= this_cpu_ci->num_levels &&
+	     idx < this_cpu_ci->num_leaves; idx++, level++) {
+		ci_leaf_init(this_leaf++, CACHE_TYPE_DATA, level);
+		ci_leaf_init(this_leaf++, CACHE_TYPE_INST, level);
+	}
+	return 0;
+}