omap iommu: tlb and pagetable primitives

This patch provides:

- iotlb_*()     : iommu tlb operations
- iopgtable_*() : iommu pagetable(twl) operations
- iommu_*()     : the other generic operations

and the entry points to register and acquire iommu object.
Signed-off-by: Hiroshi DOYU <Hiroshi.DOYU@nokia.com>

arch/arm/plat-omap/include/mach/iommu.h

+/*
+ * omap iommu: main structures
+ *
+ * Copyright (C) 2008-2009 Nokia Corporation
+ *
+ * Written by Hiroshi DOYU <Hiroshi.DOYU@nokia.com>
+ *
+ * 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.
+ */
+
+#ifndef __MACH_IOMMU_H
+#define __MACH_IOMMU_H
+
+struct iotlb_entry {
+	u32 da;
+	u32 pa;
+	u32 pgsz, prsvd, valid;
+	union {
+		u16 ap;
+		struct {
+			u32 endian, elsz, mixed;
+		};
+	};
+};
+
+struct iommu {
+	const char	*name;
+	struct module	*owner;
+	struct clk	*clk;
+	void __iomem	*regbase;
+	struct device	*dev;
+
+	unsigned int	refcount;
+	struct mutex	iommu_lock;	/* global for this whole object */
+
+	/*
+	 * We don't change iopgd for a situation like pgd for a task,
+	 * but share it globally for each iommu.
+	 */
+	u32		*iopgd;
+	spinlock_t	page_table_lock; /* protect iopgd */
+
+	int		nr_tlb_entries;
+
+	struct list_head	mmap;
+	struct mutex		mmap_lock; /* protect mmap */
+
+	int (*isr)(struct iommu *obj);
+
+	void *ctx; /* iommu context: registres saved area */
+};
+
+struct cr_regs {
+	union {
+		struct {
+			u16 cam_l;
+			u16 cam_h;
+		};
+		u32 cam;
+	};
+	union {
+		struct {
+			u16 ram_l;
+			u16 ram_h;
+		};
+		u32 ram;
+	};
+};
+
+struct iotlb_lock {
+	short base;
+	short vict;
+};
+
+/* architecture specific functions */
+struct iommu_functions {
+	unsigned long	version;
+
+	int (*enable)(struct iommu *obj);
+	void (*disable)(struct iommu *obj);
+	u32 (*fault_isr)(struct iommu *obj, u32 *ra);
+
+	void (*tlb_read_cr)(struct iommu *obj, struct cr_regs *cr);
+	void (*tlb_load_cr)(struct iommu *obj, struct cr_regs *cr);
+
+	struct cr_regs *(*alloc_cr)(struct iommu *obj, struct iotlb_entry *e);
+	int (*cr_valid)(struct cr_regs *cr);
+	u32 (*cr_to_virt)(struct cr_regs *cr);
+	void (*cr_to_e)(struct cr_regs *cr, struct iotlb_entry *e);
+	ssize_t (*dump_cr)(struct iommu *obj, struct cr_regs *cr, char *buf);
+
+	u32 (*get_pte_attr)(struct iotlb_entry *e);
+
+	void (*save_ctx)(struct iommu *obj);
+	void (*restore_ctx)(struct iommu *obj);
+	ssize_t (*dump_ctx)(struct iommu *obj, char *buf);
+};
+
+struct iommu_platform_data {
+	const char *name;
+	const char *clk_name;
+	const int nr_tlb_entries;
+};
+
+#if defined(CONFIG_ARCH_OMAP1)
+#error "iommu for this processor not implemented yet"
+#else
+#include <mach/iommu2.h>
+#endif
+
+/*
+ * utilities for super page(16MB, 1MB, 64KB and 4KB)
+ */
+
+#define iopgsz_max(bytes)			\
+	(((bytes) >= SZ_16M) ? SZ_16M :		\
+	 ((bytes) >= SZ_1M)  ? SZ_1M  :		\
+	 ((bytes) >= SZ_64K) ? SZ_64K :		\
+	 ((bytes) >= SZ_4K)  ? SZ_4K  :	0)
+
+#define bytes_to_iopgsz(bytes)				\
+	(((bytes) == SZ_16M) ? MMU_CAM_PGSZ_16M :	\
+	 ((bytes) == SZ_1M)  ? MMU_CAM_PGSZ_1M  :	\
+	 ((bytes) == SZ_64K) ? MMU_CAM_PGSZ_64K :	\
+	 ((bytes) == SZ_4K)  ? MMU_CAM_PGSZ_4K  : -1)
+
+#define iopgsz_to_bytes(iopgsz)				\
+	(((iopgsz) == MMU_CAM_PGSZ_16M)	? SZ_16M :	\
+	 ((iopgsz) == MMU_CAM_PGSZ_1M)	? SZ_1M  :	\
+	 ((iopgsz) == MMU_CAM_PGSZ_64K)	? SZ_64K :	\
+	 ((iopgsz) == MMU_CAM_PGSZ_4K)	? SZ_4K  : 0)
+
+#define iopgsz_ok(bytes) (bytes_to_iopgsz(bytes) >= 0)
+
+/*
+ * global functions
+ */
+extern u32 iommu_arch_version(void);
+
+extern void iotlb_cr_to_e(struct cr_regs *cr, struct iotlb_entry *e);
+extern u32 iotlb_cr_to_virt(struct cr_regs *cr);
+
+extern int load_iotlb_entry(struct iommu *obj, struct iotlb_entry *e);
+extern void flush_iotlb_page(struct iommu *obj, u32 da);
+extern void flush_iotlb_range(struct iommu *obj, u32 start, u32 end);
+extern void flush_iotlb_all(struct iommu *obj);
+
+extern int iopgtable_store_entry(struct iommu *obj, struct iotlb_entry *e);
+extern size_t iopgtable_clear_entry(struct iommu *obj, u32 iova);
+
+extern struct iommu *iommu_get(const char *name);
+extern void iommu_put(struct iommu *obj);
+
+extern void iommu_save_ctx(struct iommu *obj);
+extern void iommu_restore_ctx(struct iommu *obj);
+
+extern int install_iommu_arch(const struct iommu_functions *ops);
+extern void uninstall_iommu_arch(const struct iommu_functions *ops);
+
+extern int foreach_iommu_device(void *data,
+				int (*fn)(struct device *, void *));
+
+extern ssize_t iommu_dump_ctx(struct iommu *obj, char *buf);
+extern size_t dump_tlb_entries(struct iommu *obj, char *buf);
+
+#endif /* __MACH_IOMMU_H */

arch/arm/plat-omap/iopgtable.h

+/*
+ * omap iommu: pagetable definitions
+ *
+ * Copyright (C) 2008-2009 Nokia Corporation
+ *
+ * Written by Hiroshi DOYU <Hiroshi.DOYU@nokia.com>
+ *
+ * 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.
+ */
+
+#ifndef __PLAT_OMAP_IOMMU_H
+#define __PLAT_OMAP_IOMMU_H
+
+#define IOPGD_SHIFT		20
+#define IOPGD_SIZE		(1 << IOPGD_SHIFT)
+#define IOPGD_MASK		(~(IOPGD_SIZE - 1))
+#define IOSECTION_MASK		IOPGD_MASK
+#define PTRS_PER_IOPGD		(1 << (32 - IOPGD_SHIFT))
+#define IOPGD_TABLE_SIZE	(PTRS_PER_IOPGD * sizeof(u32))
+
+#define IOSUPER_SIZE		(IOPGD_SIZE << 4)
+#define IOSUPER_MASK		(~(IOSUPER_SIZE - 1))
+
+#define IOPTE_SHIFT		12
+#define IOPTE_SIZE		(1 << IOPTE_SHIFT)
+#define IOPTE_MASK		(~(IOPTE_SIZE - 1))
+#define IOPAGE_MASK		IOPTE_MASK
+#define PTRS_PER_IOPTE		(1 << (IOPGD_SHIFT - IOPTE_SHIFT))
+#define IOPTE_TABLE_SIZE	(PTRS_PER_IOPTE * sizeof(u32))
+
+#define IOLARGE_SIZE		(IOPTE_SIZE << 4)
+#define IOLARGE_MASK		(~(IOLARGE_SIZE - 1))
+
+#define IOPGD_TABLE		(1 << 0)
+#define IOPGD_SECTION		(2 << 0)
+#define IOPGD_SUPER		(1 << 18 | 2 << 0)
+
+#define IOPTE_SMALL		(2 << 0)
+#define IOPTE_LARGE		(1 << 0)
+
+#define iopgd_index(da)		(((da) >> IOPGD_SHIFT) & (PTRS_PER_IOPGD - 1))
+#define iopgd_offset(obj, da)	((obj)->iopgd + iopgd_index(da))
+
+#define iopte_paddr(iopgd)	(*iopgd & ~((1 << 10) - 1))
+#define iopte_vaddr(iopgd)	((u32 *)phys_to_virt(iopte_paddr(iopgd)))
+
+#define iopte_index(da)		(((da) >> IOPTE_SHIFT) & (PTRS_PER_IOPTE - 1))
+#define iopte_offset(iopgd, da)	(iopte_vaddr(iopgd) + iopte_index(da))
+
+static inline u32 iotlb_init_entry(struct iotlb_entry *e, u32 da, u32 pa,
+				   u32 flags)
+{
+	memset(e, 0, sizeof(*e));
+
+	e->da		= da;
+	e->pa		= pa;
+	e->valid	= 1;
+	/* FIXME: add OMAP1 support */
+	e->pgsz		= flags & MMU_CAM_PGSZ_MASK;
+	e->endian	= flags & MMU_RAM_ENDIAN_MASK;
+	e->elsz		= flags & MMU_RAM_ELSZ_MASK;
+	e->mixed	= flags & MMU_RAM_MIXED_MASK;
+
+	return iopgsz_to_bytes(e->pgsz);
+}
+
+#define to_iommu(dev)							\
+	(struct iommu *)platform_get_drvdata(to_platform_device(dev))
+
+#endif /* __PLAT_OMAP_IOMMU_H */