text: #ifndef __NVKM_FBRAM_FUC_H__
  #define __NVKM_FBRAM_FUC_H__
  
  #include <subdev/pwr.h>
  
  struct ramfuc {
  	struct nouveau_memx *memx;
  	struct nouveau_fb *pfb;
  	int sequence;
  };
  
  struct ramfuc_reg {
  	int sequence;
  	bool force;
  	u32 addr;
  	u32 stride; /* in bytes */
  	u32 mask;
  	u32 data;
  };
  
  static inline struct ramfuc_reg
  ramfuc_stride(u32 addr, u32 stride, u32 mask)
  {
  	return (struct ramfuc_reg) {
  		.sequence = 0,
  		.addr = addr,
  		.stride = stride,
  		.mask = mask,
  		.data = 0xdeadbeef,
  	};
  }
  
  static inline struct ramfuc_reg
  ramfuc_reg2(u32 addr1, u32 addr2)
  {
  	return (struct ramfuc_reg) {
  		.sequence = 0,
  		.addr = addr1,
  		.stride = addr2 - addr1,
  		.mask = 0x3,
  		.data = 0xdeadbeef,
  	};
  }
  
  static noinline struct ramfuc_reg
  ramfuc_reg(u32 addr)
  {
  	return (struct ramfuc_reg) {
  		.sequence = 0,
  		.addr = addr,
  		.stride = 0,
  		.mask = 0x1,
  		.data = 0xdeadbeef,
  	};
  }
  
  static inline int
  ramfuc_init(struct ramfuc *ram, struct nouveau_fb *pfb)
  {
  	struct nouveau_pwr *ppwr = nouveau_pwr(pfb);
  	int ret;
  
  	ret = nouveau_memx_init(ppwr, &ram->memx);
  	if (ret)
  		return ret;
  
  	ram->sequence++;
  	ram->pfb = pfb;
  	return 0;
  }
  
  static inline int
  ramfuc_exec(struct ramfuc *ram, bool exec)
  {
  	int ret = 0;
  	if (ram->pfb) {
  		ret = nouveau_memx_fini(&ram->memx, exec);
  		ram->pfb = NULL;
  	}
  	return ret;
  }
  
  static inline u32
  ramfuc_rd32(struct ramfuc *ram, struct ramfuc_reg *reg)
  {
  	if (reg->sequence != ram->sequence)
  		reg->data = nv_rd32(ram->pfb, reg->addr);
  	return reg->data;
  }
  
  static inline void
  ramfuc_wr32(struct ramfuc *ram, struct ramfuc_reg *reg, u32 data)
  {
  	unsigned int mask, off = 0;
  
  	reg->sequence = ram->sequence;
  	reg->data = data;
  
  	for (mask = reg->mask; mask > 0; mask = (mask & ~1) >> 1) {
  		if (mask & 1) {
  			nouveau_memx_wr32(ram->memx, reg->addr+off, reg->data);
  		}
  
  		off += reg->stride;
  	}
  }
  
  static inline void
  ramfuc_nuke(struct ramfuc *ram, struct ramfuc_reg *reg)
  {
  	reg->force = true;
  }
  
  static inline u32
  ramfuc_mask(struct ramfuc *ram, struct ramfuc_reg *reg, u32 mask, u32 data)
  {
  	u32 temp = ramfuc_rd32(ram, reg);
  	if (temp != ((temp & ~mask) | data) || reg->force) {
  		ramfuc_wr32(ram, reg, (temp & ~mask) | data);
  		reg->force = false;
  	}
  	return temp;
  }
  
  static inline void
  ramfuc_wait(struct ramfuc *ram, u32 addr, u32 mask, u32 data, u32 nsec)
  {
  	nouveau_memx_wait(ram->memx, addr, mask, data, nsec);
  }
  
  static inline void
  ramfuc_nsec(struct ramfuc *ram, u32 nsec)
  {
  	nouveau_memx_nsec(ram->memx, nsec);
  }
  
  static inline void
  ramfuc_wait_vblank(struct ramfuc *ram)
  {
  	nouveau_memx_wait_vblank(ram->memx);
  }
  
  static inline void
  ramfuc_block(struct ramfuc *ram)
  {
  	nouveau_memx_block(ram->memx);
  }
  
  static inline void
  ramfuc_unblock(struct ramfuc *ram)
  {
  	nouveau_memx_unblock(ram->memx);
  }
  
  #define ram_init(s,p)        ramfuc_init(&(s)->base, (p))
  #define ram_exec(s,e)        ramfuc_exec(&(s)->base, (e))
  #define ram_have(s,r)        ((s)->r_##r.addr != 0x000000)
  #define ram_rd32(s,r)        ramfuc_rd32(&(s)->base, &(s)->r_##r)
  #define ram_wr32(s,r,d)      ramfuc_wr32(&(s)->base, &(s)->r_##r, (d))
  #define ram_nuke(s,r)        ramfuc_nuke(&(s)->base, &(s)->r_##r)
  #define ram_mask(s,r,m,d)    ramfuc_mask(&(s)->base, &(s)->r_##r, (m), (d))
  #define ram_wait(s,r,m,d,n)  ramfuc_wait(&(s)->base, (r), (m), (d), (n))
  #define ram_nsec(s,n)        ramfuc_nsec(&(s)->base, (n))
  #define ram_wait_vblank(s)   ramfuc_wait_vblank(&(s)->base)
  #define ram_block(s)         ramfuc_block(&(s)->base)
  #define ram_unblock(s)       ramfuc_unblock(&(s)->base)
  
  #endif
  