arm: cpu: add basic arm64 mmu support

This commit adds basic mmu support, ie:
        - DMA cache handling is not supported
        - Remapping memory region also

The current mmu setting is:
        - 4KB granularity
        - 3 level lookup (skipping L0)
        - 33 bits per VA

This is based on coreboot and u-boot mmu configuration.

Signed-off-by: Raphael Poggi <poggi.raph@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

2 files changed, 151 insertions, 3 deletions

diff --git a/arch/arm/include/asm/mmu.h b/arch/arm/include/asm/mmu.h
index 8de6544657..f68ab37143 100644
--- a/arch/arm/include/asm/mmu.h
+++ b/arch/arm/include/asm/mmu.h
@@ -6,16 +6,24 @@
 #include <malloc.h>
 #include <xfuncs.h>
 
+#ifdef CONFIG_CPU_64v8
+#include <asm/pgtable64.h>
+
+#define DEV_MEM		(PMD_ATTRINDX(MT_DEVICE_nGnRnE) | PMD_SECT_AF | PMD_TYPE_SECT)
+#define CACHED_MEM	(PMD_ATTRINDX(MT_NORMAL) | PMD_SECT_S | PMD_SECT_AF | PMD_TYPE_SECT)
+#define UNCACHED_MEM	(PMD_ATTRINDX(MT_NORMAL_NC) | PMD_SECT_S | PMD_SECT_AF | PMD_TYPE_SECT)
+#else
 #include <asm/pgtable.h>
 
 #define PMD_SECT_DEF_UNCACHED (PMD_SECT_AP_WRITE | PMD_SECT_AP_READ | PMD_TYPE_SECT)
 #define PMD_SECT_DEF_CACHED (PMD_SECT_WB | PMD_SECT_DEF_UNCACHED)
+#endif
+
+
 
 struct arm_memory;
 
-static inline void mmu_enable(void)
-{
-}
+void mmu_enable(void);
 void mmu_disable(void);
 static inline void arm_create_section(unsigned long virt, unsigned long phys, int size_m,
 		unsigned int flags)
diff --git a/arch/arm/include/asm/pgtable64.h b/arch/arm/include/asm/pgtable64.h
new file mode 100644
index 0000000000..20bea5b28a
--- /dev/null
+++ b/arch/arm/include/asm/pgtable64.h
@@ -0,0 +1,140 @@
+/*
+ * Copyright (C) 2012 ARM Ltd.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#ifndef __ASM_PGTABLE64_H
+#define __ASM_PGTABLE64_H
+
+#define UL(x)		_AC(x, UL)
+
+#define UNUSED_DESC                0x6EbAAD0BBADbA6E0
+
+#define VA_START                   0x0
+#define BITS_PER_VA                33
+
+/* Granule size of 4KB is being used */
+#define GRANULE_SIZE_SHIFT         12
+#define GRANULE_SIZE               (1 << GRANULE_SIZE_SHIFT)
+#define XLAT_ADDR_MASK             ((1UL << BITS_PER_VA) - GRANULE_SIZE)
+#define GRANULE_SIZE_MASK          ((1 << GRANULE_SIZE_SHIFT) - 1)
+
+#define BITS_RESOLVED_PER_LVL   (GRANULE_SIZE_SHIFT - 3)
+#define L1_ADDR_SHIFT           (GRANULE_SIZE_SHIFT + BITS_RESOLVED_PER_LVL * 2)
+#define L2_ADDR_SHIFT           (GRANULE_SIZE_SHIFT + BITS_RESOLVED_PER_LVL * 1)
+#define L3_ADDR_SHIFT           (GRANULE_SIZE_SHIFT + BITS_RESOLVED_PER_LVL * 0)
+
+
+#define L1_ADDR_MASK     (((1UL << BITS_RESOLVED_PER_LVL) - 1) << L1_ADDR_SHIFT)
+#define L2_ADDR_MASK     (((1UL << BITS_RESOLVED_PER_LVL) - 1) << L2_ADDR_SHIFT)
+#define L3_ADDR_MASK     (((1UL << BITS_RESOLVED_PER_LVL) - 1) << L3_ADDR_SHIFT)
+
+/* These macros give the size of the region addressed by each entry of a xlat
+   table at any given level */
+#define L3_XLAT_SIZE               (1UL << L3_ADDR_SHIFT)
+#define L2_XLAT_SIZE               (1UL << L2_ADDR_SHIFT)
+#define L1_XLAT_SIZE               (1UL << L1_ADDR_SHIFT)
+
+#define GRANULE_MASK	GRANULE_SIZE
+
+
+/*
+ * Level 2 descriptor (PMD).
+ */
+#define PMD_TYPE_MASK		(3 << 0)
+#define PMD_TYPE_FAULT		(0 << 0)
+#define PMD_TYPE_TABLE		(3 << 0)
+#define PMD_TYPE_SECT		(1 << 0)
+#define PMD_TABLE_BIT		(1 << 1)
+
+/*
+ * Section
+ */
+#define PMD_SECT_VALID		(1 << 0)
+#define PMD_SECT_USER		(1 << 6)		/* AP[1] */
+#define PMD_SECT_RDONLY		(1 << 7)		/* AP[2] */
+#define PMD_SECT_S		(3 << 8)
+#define PMD_SECT_AF		(1 << 10)
+#define PMD_SECT_NG		(1 << 11)
+#define PMD_SECT_CONT		(1 << 52)
+#define PMD_SECT_PXN		(1 << 53)
+#define PMD_SECT_UXN		(1 << 54)
+
+/*
+ * AttrIndx[2:0] encoding (mapping attributes defined in the MAIR* registers).
+ */
+#define PMD_ATTRINDX(t)		((t) << 2)
+#define PMD_ATTRINDX_MASK	(7 << 2)
+
+/*
+ * Level 3 descriptor (PTE).
+ */
+#define PTE_TYPE_MASK		(3 << 0)
+#define PTE_TYPE_FAULT		(0 << 0)
+#define PTE_TYPE_PAGE		(3 << 0)
+#define PTE_TABLE_BIT		(1 << 1)
+#define PTE_USER		(1 << 6)		/* AP[1] */
+#define PTE_RDONLY		(1 << 7)		/* AP[2] */
+#define PTE_SHARED		(3 << 8)		/* SH[1:0], inner shareable */
+#define PTE_AF			(1 << 10)	/* Access Flag */
+#define PTE_NG			(1 << 11)	/* nG */
+#define PTE_DBM			(1 << 51)	/* Dirty Bit Management */
+#define PTE_CONT		(1 << 52)	/* Contiguous range */
+#define PTE_PXN			(1 << 53)	/* Privileged XN */
+#define PTE_UXN			(1 << 54)	/* User XN */
+
+/*
+ * AttrIndx[2:0] encoding (mapping attributes defined in the MAIR* registers).
+ */
+#define PTE_ATTRINDX(t)		((t) << 2)
+#define PTE_ATTRINDX_MASK	(7 << 2)
+
+/*
+ * Memory types available.
+ */
+#define MT_DEVICE_nGnRnE	0
+#define MT_DEVICE_nGnRE		1
+#define MT_DEVICE_GRE		2
+#define MT_NORMAL_NC		3
+#define MT_NORMAL		4
+#define MT_NORMAL_WT		5
+
+/*
+ * TCR flags.
+ */
+#define TCR_T0SZ(x)		((64 - (x)) << 0)
+#define TCR_IRGN_NC		(0 << 8)
+#define TCR_IRGN_WBWA		(1 << 8)
+#define TCR_IRGN_WT		(2 << 8)
+#define TCR_IRGN_WBNWA		(3 << 8)
+#define TCR_IRGN_MASK		(3 << 8)
+#define TCR_ORGN_NC		(0 << 10)
+#define TCR_ORGN_WBWA		(1 << 10)
+#define TCR_ORGN_WT		(2 << 10)
+#define TCR_ORGN_WBNWA		(3 << 10)
+#define TCR_ORGN_MASK		(3 << 10)
+#define TCR_SHARED_NON		(0 << 12)
+#define TCR_SHARED_OUTER	(2 << 12)
+#define TCR_SHARED_INNER	(3 << 12)
+#define TCR_TG0_4K		(0 << 14)
+#define TCR_TG0_64K		(1 << 14)
+#define TCR_TG0_16K		(2 << 14)
+#define TCR_EL1_IPS_BITS	(UL(3) << 32)	/* 42 bits physical address */
+#define TCR_EL2_IPS_BITS	(3 << 16)	/* 42 bits physical address */
+#define TCR_EL3_IPS_BITS	(3 << 16)	/* 42 bits physical address */
+
+#define TCR_EL1_RSVD		(1 << 31)
+#define TCR_EL2_RSVD		(1 << 31 | 1 << 23)
+#define TCR_EL3_RSVD		(1 << 31 | 1 << 23)
+
+#endif