csky: Cache and TLB routines

This patch adds cache and tlb sync codes for abiv1 & abiv2.

Signed-off-by: Guo Ren <ren_guo@c-sky.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>

4 files changed, 456 insertions, 0 deletions

diff --git a/arch/csky/mm/cachev1.c b/arch/csky/mm/cachev1.c
new file mode 100644
index 000000000000..b8a75cce0b8c
--- /dev/null
+++ b/arch/csky/mm/cachev1.c
@@ -0,0 +1,126 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
+
+#include <linux/spinlock.h>
+#include <asm/cache.h>
+#include <abi/reg_ops.h>
+
+/* for L1-cache */
+#define INS_CACHE		(1 << 0)
+#define DATA_CACHE		(1 << 1)
+#define CACHE_INV		(1 << 4)
+#define CACHE_CLR		(1 << 5)
+#define CACHE_OMS		(1 << 6)
+#define CACHE_ITS		(1 << 7)
+#define CACHE_LICF		(1 << 31)
+
+/* for L2-cache */
+#define CR22_LEVEL_SHIFT	(1)
+#define CR22_SET_SHIFT		(7)
+#define CR22_WAY_SHIFT		(30)
+#define CR22_WAY_SHIFT_L2	(29)
+
+static DEFINE_SPINLOCK(cache_lock);
+
+static inline void cache_op_line(unsigned long i, unsigned int val)
+{
+	mtcr("cr22", i);
+	mtcr("cr17", val);
+}
+
+#define CCR2_L2E (1 << 3)
+static void cache_op_all(unsigned int value, unsigned int l2)
+{
+	mtcr("cr17", value | CACHE_CLR);
+	mb();
+
+	if (l2 && (mfcr_ccr2() & CCR2_L2E)) {
+		mtcr("cr24", value | CACHE_CLR);
+		mb();
+	}
+}
+
+static void cache_op_range(
+	unsigned int start,
+	unsigned int end,
+	unsigned int value,
+	unsigned int l2)
+{
+	unsigned long i, flags;
+	unsigned int val = value | CACHE_CLR | CACHE_OMS;
+	bool l2_sync;
+
+	if (unlikely((end - start) >= PAGE_SIZE) ||
+	    unlikely(start < PAGE_OFFSET) ||
+	    unlikely(start >= PAGE_OFFSET + LOWMEM_LIMIT)) {
+		cache_op_all(value, l2);
+		return;
+	}
+
+	if ((mfcr_ccr2() & CCR2_L2E) && l2)
+		l2_sync = 1;
+	else
+		l2_sync = 0;
+
+	spin_lock_irqsave(&cache_lock, flags);
+
+	i = start & ~(L1_CACHE_BYTES - 1);
+	for (; i < end; i += L1_CACHE_BYTES) {
+		cache_op_line(i, val);
+		if (l2_sync) {
+			mb();
+			mtcr("cr24", val);
+		}
+	}
+	spin_unlock_irqrestore(&cache_lock, flags);
+
+	mb();
+}
+
+void dcache_wb_line(unsigned long start)
+{
+	asm volatile("idly4\n":::"memory");
+	cache_op_line(start, DATA_CACHE|CACHE_CLR);
+	mb();
+}
+
+void icache_inv_range(unsigned long start, unsigned long end)
+{
+	cache_op_range(start, end, INS_CACHE|CACHE_INV, 0);
+}
+
+void icache_inv_all(void)
+{
+	cache_op_all(INS_CACHE|CACHE_INV, 0);
+}
+
+void dcache_wb_range(unsigned long start, unsigned long end)
+{
+	cache_op_range(start, end, DATA_CACHE|CACHE_CLR, 0);
+}
+
+void dcache_wbinv_all(void)
+{
+	cache_op_all(DATA_CACHE|CACHE_CLR|CACHE_INV, 0);
+}
+
+void cache_wbinv_range(unsigned long start, unsigned long end)
+{
+	cache_op_range(start, end, INS_CACHE|DATA_CACHE|CACHE_CLR|CACHE_INV, 0);
+}
+EXPORT_SYMBOL(cache_wbinv_range);
+
+void cache_wbinv_all(void)
+{
+	cache_op_all(INS_CACHE|DATA_CACHE|CACHE_CLR|CACHE_INV, 0);
+}
+
+void dma_wbinv_range(unsigned long start, unsigned long end)
+{
+	cache_op_range(start, end, DATA_CACHE|CACHE_CLR|CACHE_INV, 1);
+}
+
+void dma_wb_range(unsigned long start, unsigned long end)
+{
+	cache_op_range(start, end, DATA_CACHE|CACHE_INV, 1);
+}
diff --git a/arch/csky/mm/cachev2.c b/arch/csky/mm/cachev2.c
new file mode 100644
index 000000000000..baaf05d69f44
--- /dev/null
+++ b/arch/csky/mm/cachev2.c
@@ -0,0 +1,79 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
+
+#include <linux/spinlock.h>
+#include <linux/smp.h>
+#include <asm/cache.h>
+#include <asm/barrier.h>
+
+inline void dcache_wb_line(unsigned long start)
+{
+	asm volatile("dcache.cval1 %0\n"::"r"(start):"memory");
+	sync_is();
+}
+
+void icache_inv_range(unsigned long start, unsigned long end)
+{
+	unsigned long i = start & ~(L1_CACHE_BYTES - 1);
+
+	for (; i < end; i += L1_CACHE_BYTES)
+		asm volatile("icache.iva %0\n"::"r"(i):"memory");
+	sync_is();
+}
+
+void icache_inv_all(void)
+{
+	asm volatile("icache.ialls\n":::"memory");
+	sync_is();
+}
+
+void dcache_wb_range(unsigned long start, unsigned long end)
+{
+	unsigned long i = start & ~(L1_CACHE_BYTES - 1);
+
+	for (; i < end; i += L1_CACHE_BYTES)
+		asm volatile("dcache.cval1 %0\n"::"r"(i):"memory");
+	sync_is();
+}
+
+void dcache_inv_range(unsigned long start, unsigned long end)
+{
+	unsigned long i = start & ~(L1_CACHE_BYTES - 1);
+
+	for (; i < end; i += L1_CACHE_BYTES)
+		asm volatile("dcache.civa %0\n"::"r"(i):"memory");
+	sync_is();
+}
+
+void cache_wbinv_range(unsigned long start, unsigned long end)
+{
+	unsigned long i = start & ~(L1_CACHE_BYTES - 1);
+
+	for (; i < end; i += L1_CACHE_BYTES)
+		asm volatile("dcache.cval1 %0\n"::"r"(i):"memory");
+	sync_is();
+
+	i = start & ~(L1_CACHE_BYTES - 1);
+	for (; i < end; i += L1_CACHE_BYTES)
+		asm volatile("icache.iva %0\n"::"r"(i):"memory");
+	sync_is();
+}
+EXPORT_SYMBOL(cache_wbinv_range);
+
+void dma_wbinv_range(unsigned long start, unsigned long end)
+{
+	unsigned long i = start & ~(L1_CACHE_BYTES - 1);
+
+	for (; i < end; i += L1_CACHE_BYTES)
+		asm volatile("dcache.civa %0\n"::"r"(i):"memory");
+	sync_is();
+}
+
+void dma_wb_range(unsigned long start, unsigned long end)
+{
+	unsigned long i = start & ~(L1_CACHE_BYTES - 1);
+
+	for (; i < end; i += L1_CACHE_BYTES)
+		asm volatile("dcache.civa %0\n"::"r"(i):"memory");
+	sync_is();
+}
diff --git a/arch/csky/mm/syscache.c b/arch/csky/mm/syscache.c
new file mode 100644
index 000000000000..c4645e4e97f4
--- /dev/null
+++ b/arch/csky/mm/syscache.c
@@ -0,0 +1,32 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
+
+#include <linux/syscalls.h>
+#include <asm/page.h>
+#include <asm/cache.h>
+#include <asm/cachectl.h>
+
+SYSCALL_DEFINE3(cacheflush,
+		void __user *, addr,
+		unsigned long, bytes,
+		int, cache)
+{
+	switch (cache) {
+	case ICACHE:
+		icache_inv_range((unsigned long)addr,
+				 (unsigned long)addr + bytes);
+		break;
+	case DCACHE:
+		dcache_wb_range((unsigned long)addr,
+				(unsigned long)addr + bytes);
+		break;
+	case BCACHE:
+		cache_wbinv_range((unsigned long)addr,
+				  (unsigned long)addr + bytes);
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return 0;
+}
diff --git a/arch/csky/mm/tlb.c b/arch/csky/mm/tlb.c
new file mode 100644
index 000000000000..08b8394e5b8f
--- /dev/null
+++ b/arch/csky/mm/tlb.c
@@ -0,0 +1,219 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
+
+#include <linux/init.h>
+#include <linux/mm.h>
+#include <linux/module.h>
+#include <linux/sched.h>
+
+#include <asm/mmu_context.h>
+#include <asm/pgtable.h>
+#include <asm/setup.h>
+
+#define CSKY_TLB_SIZE CONFIG_CPU_TLB_SIZE
+
+void flush_tlb_all(void)
+{
+	tlb_invalid_all();
+}
+
+void flush_tlb_mm(struct mm_struct *mm)
+{
+	int cpu = smp_processor_id();
+
+	if (cpu_context(cpu, mm) != 0)
+		drop_mmu_context(mm, cpu);
+
+	tlb_invalid_all();
+}
+
+#define restore_asid_inv_utlb(oldpid, newpid) \
+do { \
+	if ((oldpid & ASID_MASK) == newpid) \
+		write_mmu_entryhi(oldpid + 1); \
+	write_mmu_entryhi(oldpid); \
+} while (0)
+
+void flush_tlb_range(struct vm_area_struct *vma, unsigned long start,
+			   unsigned long end)
+{
+	struct mm_struct *mm = vma->vm_mm;
+	int cpu = smp_processor_id();
+
+	if (cpu_context(cpu, mm) != 0) {
+		unsigned long size, flags;
+		int newpid = cpu_asid(cpu, mm);
+
+		local_irq_save(flags);
+		size = (end - start + (PAGE_SIZE - 1)) >> PAGE_SHIFT;
+		size = (size + 1) >> 1;
+		if (size <= CSKY_TLB_SIZE/2) {
+			start &= (PAGE_MASK << 1);
+			end += ((PAGE_SIZE << 1) - 1);
+			end &= (PAGE_MASK << 1);
+#ifdef CONFIG_CPU_HAS_TLBI
+			while (start < end) {
+				asm volatile("tlbi.vaas %0"
+					     ::"r"(start | newpid));
+				start += (PAGE_SIZE << 1);
+			}
+			sync_is();
+#else
+			{
+			int oldpid = read_mmu_entryhi();
+
+			while (start < end) {
+				int idx;
+
+				write_mmu_entryhi(start | newpid);
+				start += (PAGE_SIZE << 1);
+				tlb_probe();
+				idx = read_mmu_index();
+				if (idx >= 0)
+					tlb_invalid_indexed();
+			}
+			restore_asid_inv_utlb(oldpid, newpid);
+			}
+#endif
+		} else {
+			drop_mmu_context(mm, cpu);
+		}
+		local_irq_restore(flags);
+	}
+}
+
+void flush_tlb_kernel_range(unsigned long start, unsigned long end)
+{
+	unsigned long size, flags;
+
+	local_irq_save(flags);
+	size = (end - start + (PAGE_SIZE - 1)) >> PAGE_SHIFT;
+	if (size <= CSKY_TLB_SIZE) {
+		start &= (PAGE_MASK << 1);
+		end += ((PAGE_SIZE << 1) - 1);
+		end &= (PAGE_MASK << 1);
+#ifdef CONFIG_CPU_HAS_TLBI
+		while (start < end) {
+			asm volatile("tlbi.vaas %0"::"r"(start));
+			start += (PAGE_SIZE << 1);
+		}
+		sync_is();
+#else
+		{
+		int oldpid = read_mmu_entryhi();
+
+		while (start < end) {
+			int idx;
+
+			write_mmu_entryhi(start);
+			start += (PAGE_SIZE << 1);
+			tlb_probe();
+			idx = read_mmu_index();
+			if (idx >= 0)
+				tlb_invalid_indexed();
+		}
+		restore_asid_inv_utlb(oldpid, 0);
+		}
+#endif
+	} else {
+		flush_tlb_all();
+	}
+
+	local_irq_restore(flags);
+}
+
+void flush_tlb_page(struct vm_area_struct *vma, unsigned long page)
+{
+	int cpu = smp_processor_id();
+	int newpid = cpu_asid(cpu, vma->vm_mm);
+
+	if (!vma || cpu_context(cpu, vma->vm_mm) != 0) {
+		page &= (PAGE_MASK << 1);
+
+#ifdef CONFIG_CPU_HAS_TLBI
+		asm volatile("tlbi.vaas %0"::"r"(page | newpid));
+		sync_is();
+#else
+		{
+		int oldpid, idx;
+		unsigned long flags;
+
+		local_irq_save(flags);
+		oldpid = read_mmu_entryhi();
+		write_mmu_entryhi(page | newpid);
+		tlb_probe();
+		idx = read_mmu_index();
+		if (idx >= 0)
+			tlb_invalid_indexed();
+
+		restore_asid_inv_utlb(oldpid, newpid);
+		local_irq_restore(flags);
+		}
+#endif
+	}
+}
+
+/*
+ * Remove one kernel space TLB entry.  This entry is assumed to be marked
+ * global so we don't do the ASID thing.
+ */
+void flush_tlb_one(unsigned long page)
+{
+	int oldpid;
+
+	oldpid = read_mmu_entryhi();
+	page &= (PAGE_MASK << 1);
+
+#ifdef CONFIG_CPU_HAS_TLBI
+	page = page | (oldpid & 0xfff);
+	asm volatile("tlbi.vaas %0"::"r"(page));
+	sync_is();
+#else
+	{
+	int idx;
+	unsigned long flags;
+
+	page = page | (oldpid & 0xff);
+
+	local_irq_save(flags);
+	write_mmu_entryhi(page);
+	tlb_probe();
+	idx = read_mmu_index();
+	if (idx >= 0)
+		tlb_invalid_indexed();
+	restore_asid_inv_utlb(oldpid, oldpid);
+	local_irq_restore(flags);
+	}
+#endif
+}
+EXPORT_SYMBOL(flush_tlb_one);
+
+/* show current 32 jtlbs */
+void show_jtlb_table(void)
+{
+	unsigned long flags;
+	int entryhi, entrylo0, entrylo1;
+	int entry;
+	int oldpid;
+
+	local_irq_save(flags);
+	entry = 0;
+	pr_info("\n\n\n");
+
+	oldpid = read_mmu_entryhi();
+	while (entry < CSKY_TLB_SIZE) {
+		write_mmu_index(entry);
+		tlb_read();
+		entryhi = read_mmu_entryhi();
+		entrylo0 = read_mmu_entrylo0();
+		entrylo0 = entrylo0;
+		entrylo1 = read_mmu_entrylo1();
+		entrylo1 = entrylo1;
+		pr_info("jtlb[%d]:	entryhi - 0x%x;	entrylo0 - 0x%x;"
+			"	entrylo1 - 0x%x\n",
+			entry, entryhi, entrylo0, entrylo1);
+		entry++;
+	}
+	write_mmu_entryhi(oldpid);
+	local_irq_restore(flags);
+}