linux/drivers/dma/mv_xor.h
Thomas Petazzoni e03bc654f8 mv_xor: support big endian systems using descriptor swap feature
The mv_xor driver had never been used in a big-endian context, and
therefore was not using the hardware features to support such an
execution environment. The hardware provides a "descriptor swap" bit
that automatically swaps the bytes of the DMA descriptors, within
blocks of 8 bytes. This requires a different DMA descriptor layout on
big-endian systems, as well as enabling this "descriptor swap" bit.

This mechanism is exactly identical to the one already used in the
mv643xx_eth network driver and the mvneta network driver.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Dan Williams <djbw@fb.com>
2013-08-22 22:57:37 -07:00

197 lines
6.8 KiB
C

/*
* Copyright (C) 2007, 2008, Marvell International Ltd.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope 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, write to the Free Software Foundation,
* Inc., 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
*/
#ifndef MV_XOR_H
#define MV_XOR_H
#include <linux/types.h>
#include <linux/io.h>
#include <linux/dmaengine.h>
#include <linux/interrupt.h>
#define USE_TIMER
#define MV_XOR_POOL_SIZE PAGE_SIZE
#define MV_XOR_SLOT_SIZE 64
#define MV_XOR_THRESHOLD 1
#define MV_XOR_MAX_CHANNELS 2
/* Values for the XOR_CONFIG register */
#define XOR_OPERATION_MODE_XOR 0
#define XOR_OPERATION_MODE_MEMCPY 2
#define XOR_DESCRIPTOR_SWAP BIT(14)
#define XOR_CURR_DESC(chan) (chan->mmr_base + 0x210 + (chan->idx * 4))
#define XOR_NEXT_DESC(chan) (chan->mmr_base + 0x200 + (chan->idx * 4))
#define XOR_BYTE_COUNT(chan) (chan->mmr_base + 0x220 + (chan->idx * 4))
#define XOR_DEST_POINTER(chan) (chan->mmr_base + 0x2B0 + (chan->idx * 4))
#define XOR_BLOCK_SIZE(chan) (chan->mmr_base + 0x2C0 + (chan->idx * 4))
#define XOR_INIT_VALUE_LOW(chan) (chan->mmr_base + 0x2E0)
#define XOR_INIT_VALUE_HIGH(chan) (chan->mmr_base + 0x2E4)
#define XOR_CONFIG(chan) (chan->mmr_base + 0x10 + (chan->idx * 4))
#define XOR_ACTIVATION(chan) (chan->mmr_base + 0x20 + (chan->idx * 4))
#define XOR_INTR_CAUSE(chan) (chan->mmr_base + 0x30)
#define XOR_INTR_MASK(chan) (chan->mmr_base + 0x40)
#define XOR_ERROR_CAUSE(chan) (chan->mmr_base + 0x50)
#define XOR_ERROR_ADDR(chan) (chan->mmr_base + 0x60)
#define XOR_INTR_MASK_VALUE 0x3F5
#define WINDOW_BASE(w) (0x250 + ((w) << 2))
#define WINDOW_SIZE(w) (0x270 + ((w) << 2))
#define WINDOW_REMAP_HIGH(w) (0x290 + ((w) << 2))
#define WINDOW_BAR_ENABLE(chan) (0x240 + ((chan) << 2))
#define WINDOW_OVERRIDE_CTRL(chan) (0x2A0 + ((chan) << 2))
struct mv_xor_device {
void __iomem *xor_base;
void __iomem *xor_high_base;
struct clk *clk;
struct mv_xor_chan *channels[MV_XOR_MAX_CHANNELS];
};
/**
* struct mv_xor_chan - internal representation of a XOR channel
* @pending: allows batching of hardware operations
* @lock: serializes enqueue/dequeue operations to the descriptors pool
* @mmr_base: memory mapped register base
* @idx: the index of the xor channel
* @chain: device chain view of the descriptors
* @completed_slots: slots completed by HW but still need to be acked
* @device: parent device
* @common: common dmaengine channel object members
* @last_used: place holder for allocation to continue from where it left off
* @all_slots: complete domain of slots usable by the channel
* @slots_allocated: records the actual size of the descriptor slot pool
* @irq_tasklet: bottom half where mv_xor_slot_cleanup runs
*/
struct mv_xor_chan {
int pending;
spinlock_t lock; /* protects the descriptor slot pool */
void __iomem *mmr_base;
unsigned int idx;
int irq;
enum dma_transaction_type current_type;
struct list_head chain;
struct list_head completed_slots;
dma_addr_t dma_desc_pool;
void *dma_desc_pool_virt;
size_t pool_size;
struct dma_device dmadev;
struct dma_chan dmachan;
struct mv_xor_desc_slot *last_used;
struct list_head all_slots;
int slots_allocated;
struct tasklet_struct irq_tasklet;
#ifdef USE_TIMER
unsigned long cleanup_time;
u32 current_on_last_cleanup;
#endif
};
/**
* struct mv_xor_desc_slot - software descriptor
* @slot_node: node on the mv_xor_chan.all_slots list
* @chain_node: node on the mv_xor_chan.chain list
* @completed_node: node on the mv_xor_chan.completed_slots list
* @hw_desc: virtual address of the hardware descriptor chain
* @phys: hardware address of the hardware descriptor chain
* @group_head: first operation in a transaction
* @slot_cnt: total slots used in an transaction (group of operations)
* @slots_per_op: number of slots per operation
* @idx: pool index
* @unmap_src_cnt: number of xor sources
* @unmap_len: transaction bytecount
* @tx_list: list of slots that make up a multi-descriptor transaction
* @async_tx: support for the async_tx api
* @xor_check_result: result of zero sum
* @crc32_result: result crc calculation
*/
struct mv_xor_desc_slot {
struct list_head slot_node;
struct list_head chain_node;
struct list_head completed_node;
enum dma_transaction_type type;
void *hw_desc;
struct mv_xor_desc_slot *group_head;
u16 slot_cnt;
u16 slots_per_op;
u16 idx;
u16 unmap_src_cnt;
u32 value;
size_t unmap_len;
struct list_head tx_list;
struct dma_async_tx_descriptor async_tx;
union {
u32 *xor_check_result;
u32 *crc32_result;
};
#ifdef USE_TIMER
unsigned long arrival_time;
struct timer_list timeout;
#endif
};
/*
* This structure describes XOR descriptor size 64bytes. The
* mv_phy_src_idx() macro must be used when indexing the values of the
* phy_src_addr[] array. This is due to the fact that the 'descriptor
* swap' feature, used on big endian systems, swaps descriptors data
* within blocks of 8 bytes. So two consecutive values of the
* phy_src_addr[] array are actually swapped in big-endian, which
* explains the different mv_phy_src_idx() implementation.
*/
#if defined(__LITTLE_ENDIAN)
struct mv_xor_desc {
u32 status; /* descriptor execution status */
u32 crc32_result; /* result of CRC-32 calculation */
u32 desc_command; /* type of operation to be carried out */
u32 phy_next_desc; /* next descriptor address pointer */
u32 byte_count; /* size of src/dst blocks in bytes */
u32 phy_dest_addr; /* destination block address */
u32 phy_src_addr[8]; /* source block addresses */
u32 reserved0;
u32 reserved1;
};
#define mv_phy_src_idx(src_idx) (src_idx)
#else
struct mv_xor_desc {
u32 crc32_result; /* result of CRC-32 calculation */
u32 status; /* descriptor execution status */
u32 phy_next_desc; /* next descriptor address pointer */
u32 desc_command; /* type of operation to be carried out */
u32 phy_dest_addr; /* destination block address */
u32 byte_count; /* size of src/dst blocks in bytes */
u32 phy_src_addr[8]; /* source block addresses */
u32 reserved1;
u32 reserved0;
};
#define mv_phy_src_idx(src_idx) (src_idx ^ 1)
#endif
#define to_mv_sw_desc(addr_hw_desc) \
container_of(addr_hw_desc, struct mv_xor_desc_slot, hw_desc)
#define mv_hw_desc_slot_idx(hw_desc, idx) \
((void *)(((unsigned long)hw_desc) + ((idx) << 5)))
#define MV_XOR_MIN_BYTE_COUNT (128)
#define XOR_MAX_BYTE_COUNT ((16 * 1024 * 1024) - 1)
#define MV_XOR_MAX_BYTE_COUNT XOR_MAX_BYTE_COUNT
#endif