1 files changed, 167 insertions, 0 deletions
diff --git a/arch/mips/include/asm/mach-powertv/ioremap.h b/arch/mips/include/asm/mach-powertv/ioremap.h
new file mode 100644
index 00000000..c86ef094
--- /dev/null
+++ b/arch/mips/include/asm/mach-powertv/ioremap.h
@@ -0,0 +1,167 @@
+/*
+ *	This program is free software; you can redistribute it and/or
+ *	modify it under the terms of the GNU General Public License
+ *	as published by the Free Software Foundation; either version
+ *	2 of the License, or (at your option) any later version.
+ *
+ * Portions Copyright (C)  Cisco Systems, Inc.
+ */
+#ifndef __ASM_MACH_POWERTV_IOREMAP_H
+#define __ASM_MACH_POWERTV_IOREMAP_H
+
+#include <linux/types.h>
+#include <linux/log2.h>
+#include <linux/compiler.h>
+
+#include <asm/pgtable-bits.h>
+#include <asm/addrspace.h>
+
+/* We're going to mess with bits, so get sizes */
+#define IOR_BPC			8			/* Bits per char */
+#define IOR_PHYS_BITS		(IOR_BPC * sizeof(phys_addr_t))
+#define IOR_DMA_BITS		(IOR_BPC * sizeof(dma_addr_t))
+
+/*
+ * Define the granularity of physical/DMA mapping in terms of the number
+ * of bits that defines the offset within a grain. These will be the
+ * least significant bits of the address. The rest of a physical or DMA
+ * address will be used to index into an appropriate table to find the
+ * offset to add to the address to yield the corresponding DMA or physical
+ * address, respectively.
+ */
+#define IOR_LSBITS		22			/* Bits in a grain */
+
+/*
+ * Compute the number of most significant address bits after removing those
+ * used for the offset within a grain and then compute the number of table
+ * entries for the conversion.
+ */
+#define IOR_PHYS_MSBITS		(IOR_PHYS_BITS - IOR_LSBITS)
+#define IOR_NUM_PHYS_TO_DMA	((phys_addr_t) 1 << IOR_PHYS_MSBITS)
+
+#define IOR_DMA_MSBITS		(IOR_DMA_BITS - IOR_LSBITS)
+#define IOR_NUM_DMA_TO_PHYS	((dma_addr_t) 1 << IOR_DMA_MSBITS)
+
+/*
+ * Define data structures used as elements in the arrays for the conversion
+ * between physical and DMA addresses. We do some slightly fancy math to
+ * compute the width of the offset element of the conversion tables so
+ * that we can have the smallest conversion tables. Next, round up the
+ * sizes to the next higher power of two, i.e. the offset element will have
+ * 8, 16, 32, 64, etc. bits. This eliminates the need to mask off any
+ * bits.  Finally, we compute a shift value that puts the most significant
+ * bits of the offset into the most significant bits of the offset element.
+ * This makes it more efficient on processors without barrel shifters and
+ * easier to see the values if the conversion table is dumped in binary.
+ */
+#define _IOR_OFFSET_WIDTH(n)	(1 << order_base_2(n))
+#define IOR_OFFSET_WIDTH(n) \
+	(_IOR_OFFSET_WIDTH(n) < 8 ? 8 : _IOR_OFFSET_WIDTH(n))
+
+#define IOR_PHYS_OFFSET_BITS	IOR_OFFSET_WIDTH(IOR_PHYS_MSBITS)
+#define IOR_PHYS_SHIFT		(IOR_PHYS_BITS - IOR_PHYS_OFFSET_BITS)
+
+#define IOR_DMA_OFFSET_BITS	IOR_OFFSET_WIDTH(IOR_DMA_MSBITS)
+#define IOR_DMA_SHIFT		(IOR_DMA_BITS - IOR_DMA_OFFSET_BITS)
+
+struct ior_phys_to_dma {
+	dma_addr_t offset:IOR_DMA_OFFSET_BITS __packed
+		__aligned((IOR_DMA_OFFSET_BITS / IOR_BPC));
+};
+
+struct ior_dma_to_phys {
+	dma_addr_t offset:IOR_PHYS_OFFSET_BITS __packed
+		__aligned((IOR_PHYS_OFFSET_BITS / IOR_BPC));
+};
+
+extern struct ior_phys_to_dma _ior_phys_to_dma[IOR_NUM_PHYS_TO_DMA];
+extern struct ior_dma_to_phys _ior_dma_to_phys[IOR_NUM_DMA_TO_PHYS];
+
+static inline dma_addr_t _phys_to_dma_offset_raw(phys_addr_t phys)
+{
+	return (dma_addr_t)_ior_phys_to_dma[phys >> IOR_LSBITS].offset;
+}
+
+static inline dma_addr_t _dma_to_phys_offset_raw(dma_addr_t dma)
+{
+	return (dma_addr_t)_ior_dma_to_phys[dma >> IOR_LSBITS].offset;
+}
+
+/* These are not portable and should not be used in drivers. Drivers should
+ * be using ioremap() and friends to map physical addresses to virtual
+ * addresses and dma_map*() and friends to map virtual addresses into DMA
+ * addresses and back.
+ */
+static inline dma_addr_t phys_to_dma(phys_addr_t phys)
+{
+	return phys + (_phys_to_dma_offset_raw(phys) << IOR_PHYS_SHIFT);
+}
+
+static inline phys_addr_t dma_to_phys(dma_addr_t dma)
+{
+	return dma + (_dma_to_phys_offset_raw(dma) << IOR_DMA_SHIFT);
+}
+
+extern void ioremap_add_map(dma_addr_t phys, phys_addr_t alias,
+	dma_addr_t size);
+
+/*
+ * Allow physical addresses to be fixed up to help peripherals located
+ * outside the low 32-bit range -- generic pass-through version.
+ */
+static inline phys_t fixup_bigphys_addr(phys_t phys_addr, phys_t size)
+{
+	return phys_addr;
+}
+
+/*
+ * Handle the special case of addresses the area aliased into the first
+ * 512 MiB of the processor's physical address space. These turn into either
+ * kseg0 or kseg1 addresses, depending on flags.
+ */
+static inline void __iomem *plat_ioremap(phys_t start, unsigned long size,
+	unsigned long flags)
+{
+	phys_addr_t start_offset;
+	void __iomem *result = NULL;
+
+	/* Start by checking to see whether this is an aliased address */
+	start_offset = _dma_to_phys_offset_raw(start);
+
+	/*
+	 * If:
+	 * o	the memory is aliased into the first 512 MiB, and
+	 * o	the start and end are in the same RAM bank, and
+	 * o	we don't have a zero size or wrap around, and
+	 * o	we are supposed to create an uncached mapping,
+	 *	handle this is a kseg0 or kseg1 address
+	 */
+	if (start_offset != 0) {
+		phys_addr_t last;
+		dma_addr_t dma_to_phys_offset;
+
+		last = start + size - 1;
+		dma_to_phys_offset =
+			_dma_to_phys_offset_raw(last) << IOR_DMA_SHIFT;
+
+		if (dma_to_phys_offset == start_offset &&
+			size != 0 && start <= last) {
+			phys_t adjusted_start;
+			adjusted_start = start + start_offset;
+			if (flags == _CACHE_UNCACHED)
+				result = (void __iomem *) (unsigned long)
+					CKSEG1ADDR(adjusted_start);
+			else
+				result = (void __iomem *) (unsigned long)
+					CKSEG0ADDR(adjusted_start);
+		}
+	}
+
+	return result;
+}
+
+static inline int plat_iounmap(const volatile void __iomem *addr)
+{
+	return 0;
+}
+#endif /* __ASM_MACH_POWERTV_IOREMAP_H */