diff options
Diffstat (limited to 'arch/mips/include/asm/mach-powertv/ioremap.h')
| -rw-r--r-- | arch/mips/include/asm/mach-powertv/ioremap.h | 165 |
1 files changed, 121 insertions, 44 deletions
diff --git a/arch/mips/include/asm/mach-powertv/ioremap.h b/arch/mips/include/asm/mach-powertv/ioremap.h index e6276d5146e..076f2eeaa57 100644 --- a/arch/mips/include/asm/mach-powertv/ioremap.h +++ b/arch/mips/include/asm/mach-powertv/ioremap.h @@ -10,64 +10,101 @@ #define __ASM_MACH_POWERTV_IOREMAP_H #include <linux/types.h> +#include <linux/log2.h> +#include <linux/compiler.h> -#define LOW_MEM_BOUNDARY_PHYS 0x20000000 -#define LOW_MEM_BOUNDARY_MASK (~(LOW_MEM_BOUNDARY_PHYS - 1)) +#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)) /* - * The bus addresses are different than the physical addresses that - * the processor sees by an offset. This offset varies by ASIC - * version. Define a variable to hold the offset and some macros to - * make the conversion simpler. */ -extern unsigned long phys_to_bus_offset; - -#ifdef CONFIG_HIGHMEM -#define MEM_GAP_PHYS 0x60000000 + * 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 */ + /* - * TODO: We will use the hard code for conversion between physical and - * bus until the bootloader releases their device tree to us. + * 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 phys_to_bus(x) (((x) < LOW_MEM_BOUNDARY_PHYS) ? \ - ((x) + phys_to_bus_offset) : (x)) -#define bus_to_phys(x) (((x) < MEM_GAP_PHYS_ADDR) ? \ - ((x) - phys_to_bus_offset) : (x)) -#else -#define phys_to_bus(x) ((x) + phys_to_bus_offset) -#define bus_to_phys(x) ((x) - phys_to_bus_offset) -#endif +#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) /* - * Determine whether the address we are given is for an ASIC device - * Params: addr Address to check - * Returns: Zero if the address is not for ASIC devices, non-zero - * if it is. + * 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. */ -static inline int asic_is_device_addr(phys_t addr) +#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 !((phys_t)addr & (phys_t) LOW_MEM_BOUNDARY_MASK); + return (dma_addr_t)_ior_phys_to_dma[phys >> IOR_LSBITS].offset; } -/* - * Determine whether the address we are given is external RAM mappable - * into KSEG1. - * Params: addr Address to check - * Returns: Zero if the address is not for external RAM and - */ -static inline int asic_is_lowmem_ram_addr(phys_t addr) +static inline dma_addr_t _dma_to_phys_offset_raw(dma_addr_t dma) { - /* - * The RAM always starts at the following address in the processor's - * physical address space - */ - static const phys_t phys_ram_base = 0x10000000; - phys_t bus_ram_base; + return (dma_addr_t)_ior_dma_to_phys[dma >> IOR_LSBITS].offset; +} - bus_ram_base = phys_to_bus_offset + phys_ram_base; +/* These are not portable and should not be used in drivers. Drivers should + * be using ioremap() and friends to map physical addreses 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); +} - return addr >= bus_ram_base && - addr < (bus_ram_base + (LOW_MEM_BOUNDARY_PHYS - phys_ram_base)); +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. @@ -77,10 +114,50 @@ static inline phys_t fixup_bigphys_addr(phys_t phys_addr, phys_t size) return phys_addr; } -static inline void __iomem *plat_ioremap(phys_t offset, unsigned long size, +/* + * 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) { - return NULL; + 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) |